* [PATCHv6 00/36] kernel: Introduce Time Namespace
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
Discussions around time namespace are there for a long time. The first
attempt to implement it was in 2006 by Jeff Dike. From that time, the
topic appears on and off in various discussions.
There are two main use cases for time namespaces:
1. change date and time inside a container;
2. adjust clocks for a container restored from a checkpoint.
“It seems like this might be one of the last major obstacles keeping
migration from being used in production systems, given that not all
containers and connections can be migrated as long as a time dependency
is capable of messing it up.” (by github.com/dav-ell)
The kernel provides access to several clocks: CLOCK_REALTIME,
CLOCK_MONOTONIC, CLOCK_BOOTTIME. Last two clocks are monotonous, but the
start points for them are not defined and are different for each
system. When a container is migrated from one node to another, all
clocks have to be restored into consistent states; in other words, they
have to continue running from the same points where they have been
dumped.
The main idea of this patch set is adding per-namespace offsets for
system clocks. When a process in a non-root time namespace requests
time of a clock, a namespace offset is added to the current value of
this clock and the sum is returned.
All offsets are placed on a separate page, this allows us to map it as
part of VVAR into user processes and use offsets from VDSO calls.
Now offsets are implemented for CLOCK_MONOTONIC and CLOCK_BOOTTIME
clocks.
v5..v6 Changes:
* Used current_is_single_threaded() instead of thread_group_empty()
(Thanks for the review, Andy).
* Changed errno code when there are threads on timens joining to
something more grepabble (EUSERS).
* posix_get_timespec() should have been posix_get_monotonic_timespec()
(Thanks, Thomas)
* timens_add_monotonic() & timens_add_boottime() were relocated to
the patch that introduces (struct timens_offsets) (Thomas)
* Avoid breaking alarmtimer for ALARM_REALTIME (Thanks, Thomas)
* Nested namespace inherits father's offsets now
(Andrei while working on CRIU side for time namespace)
* A minor conflict with commit dbc1625fc9de ("hrtimer: Consolidate
hrtimer_init() + hrtimer_init_sleeper() calls") in linux-next
[Sending against next-20190814]
[v1..v5 Changelogs is at the very bottom here]
Our performance measurements show that the price of VDSO's clock_gettime()
in a child time namespace is about 8% with a hot CPU cache and about 90%
with a cold CPU cache. There is no performance regression for host
processes outside time namespace on those tests.
We wrote two small benchmarks. The first one gettime_perf.c calls
clock_gettime() in a loop for 3 seconds. It shows us performance with
a hot CPU cache (more clock_gettime() cycles - the better):
| before | CONFIG_TIME_NS=n | host | inside timens
--------------------------------------------------------------
| 161822960 | 161147792 | 160187142 | 150584782
| 161891728 | 161489804 | 159914989 | 150417019
| 161891770 | 161098734 | 160123179 | 150601277
| 161687686 | 161114738 | 159874249 | 150243276
| 161247151 | 161411636 | 159096392 | 149637536
--------------------------------------------------------------
avg | 161708259 | 161252540 | 159839190 | 150296778
diff % | 100 | 99.7 | 98.8 | 92.9
-------------------------------------------------------------
stdev % | 0.2 | 0.1 | 0.1 | 0.2
The gettime_perf_cold test does 10K iterations. In each iteration, it
drops cpu caches for vdso pages, clflush is used for this, then it runs
rdtsc(); clock_gettime; rdtsc(); and prints the number of tsc cycles.
(lesser tsc per cycle - the better):
| before | CONFIG_TIME_NS=n | host | inside timens
--------------------------------------------------------------
tsc | 434 | 433 | 437 | 477
stdev(tsc) | 5 | 5 | 5 | 3
diff (%) | 1 | 1 | 100.1 | 109
vdsotest results: https://gist.github.com/avagin/f290afb8b721ae0522a561d585f34de0
The numbers gathered on Intel(R) Core(TM) i5-6300U CPU @ 2.40GHz.
Cc: Adrian Reber <adrian@lisas.de>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: containers@lists.linux-foundation.org
Cc: criu@openvz.org
Cc: linux-api@vger.kernel.org
Cc: x86@kernel.org
v6 on github (if someone prefers `git pull` or `git log`):
https://github.com/0x7f454c46/linux/tree/timens-v6
v5: https://lkml.kernel.org/r/20190729215758.28405-1-dima@arista.com
v4: https://lkml.kernel.org/r/20190612192628.23797-1-dima@arista.com
v3: https://lkml.kernel.org/r/20190425161416.26600-1-dima@arista.com
v2: https://lore.kernel.org/lkml/20190206001107.16488-1-dima@arista.com/
RFC: https://lkml.kernel.org/r/20180919205037.9574-1-dima@arista.com/
v4..v5 Changes:
* Rebased over generic vdso (already in master)
* Addressing review comments by Thomas Gleixner
(thanks much for your time and patience):
- Dropping `timens` prefix from subjects (it's not a subsystem)
- Keeping commit messages in a neutral technical form
- Splitting unreasonably large patches
- Document code with missing comments
- Dropped dead code that's not compiled with !CONFIG_TIME_NS
* Updated performance results [here, at the bottom]
* Split vdso jump tables patch
* Allow unshare() with many threads: it's safe until fork()/clone(),
where we check for CLONE_THREADS
* Add missed check in setns() for CLONE_VM | CLONE_THREADS
* Fixed compilation with !CONFIG_UTS_NS
* Add a plan in selftests (prevents new warning "Planned tests != run tests")
* Set jump table section address & size to (-1UL) just in case if there
is no such section while running vdso2c (and WARN() on boot in such
case)
v3..v4 Changes:
* CLOCKE_NEWTIME is unshare()-only flag now (CLON_PIDFD took previous value)
* Addressing Jann Horn's feedback - we don't allow CLONE_THREAD or
CLONE_VM together with CLONE_NEWTIME (thanks for spotting!)
* Addressing issues found by Thomas - removed unmaintainable CLOCK_TIMENS
and introduced another call back into k_clock to get ktime instead
of getting timespec and converting it (Patch 03)
* Renaming timens_offsets members to omit _offset postfix
(thanks Cyrill for the suggestion)
* Suggestions, renaming and making code more maintainable from Thomas's
feedback (thanks much!)
* Fixing out-of-bounds and other issues in procfs file (kudos Jann Horn)
* vdso_fault() can be called on a remote task by /proc/$pid/mem or
process_vm_readv() - addressed by adding a slow-path with searching
for owner's namespace (thanks for spotting this unobvious issue, Jann)
* Other nits by Jann Horn
v2..v3: Major changes:
* Simplify two VDSO images by using static_branch() in vclock_gettime()
Removes unwanted conflicts with generic VDSO movement patches and
simplifies things by dropping too invasive linker magic.
As an alternative to static_branch() we tested an attempt to introduce
home-made dynamic patching called retcalls:
https://github.com/0x7f454c46/linux/commit/4cc0180f6d65
Considering some theoretical problems with toolchains, we decided to go
with long well-tested nop-patching in static_branch(). Though, it was
needed to provide backend for relative code.
* address Thomas' comments.
* add sanity checks for offsets:
- the current clock time in a namespace has to be in [0, KTIME_MAX / 2).
KTIME_MAX is divided by two here to be sure that the KTIME_MAX limit
is still unreachable.
Link: https://lkml.org/lkml/2018/9/19/950
Link: https://lkml.org/lkml/2019/2/5/867
v1..v2: There are two major changes:
* Two versions of the VDSO library to avoid a performance penalty for
host tasks outside time namespace (as suggested by Andy and Thomas).
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
It will add a penalty for everybody as branch predictor may mispredict
the jump. Also there are instruction cache lines wasted on cmp/jmp.
Those effects of introducing time namespace are very much unwanted
having in mind how much work have been spent on micro-optimisation
VDSO code.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
* Allow to set clock offsets for a namespace only before any processes
appear in it.
Now a time namespace looks similar to a pid namespace in a way how it is
created: unshare(CLONE_NEWTIME) system call creates a new time namespace,
but doesn't set it to the current process. Then all children of
the process will be born in the new time namespace, or a process can
use the setns() system call to join a namespace.
This scheme allows to create a new time namespaces, set clock offsets
and then populate the namespace with processes.
Andrei Vagin (24):
ns: Introduce Time Namespace
timens: Add timens_offsets
posix-clocks: Rename the clock_get() into clock_get_timespec()
posix-clocks: Rename .clock_get_timespec() callbacks accordingly
alarmtimer: Rename gettime() callback to get_ktime()
alarmtimer: Provide get_timespec() callback
posix-clocks: Introduce clock_get_ktime() callback
posix-timers: Use clock_get_ktime() in common_timer_get()
posix-clocks: Wire up clock_gettime() with timens offsets
kernel: Add do_timens_ktime_to_host() helper
timerfd: Make timerfd_settime() time namespace aware
posix-timers: Make timer_settime() time namespace aware
alarmtimer: Make nanosleep time namespace aware
hrtimers: Prepare hrtimer_nanosleep() for time namespaces
posix-timers: Make clock_nanosleep() time namespace aware
x86/vdso: Add offsets page in vvar
vdso: Introduce vdso_static_branch_unlikely()
x86/vdso: Enable static branches for the timens vdso
fs/proc: Introduce /proc/pid/timens_offsets
selftest/timens: Add a test for timerfd
selftest/timens: Add a test for clock_nanosleep()
selftest/timens: Add timer offsets test
selftests/timens: Add a simple perf test for clock_gettime()
selftest/timens: Check that a right vdso is mapped after fork and exec
Dmitry Safonov (12):
fd/proc: Respect boottime inside time namespace for /proc/uptime
x86/vdso2c: Correct err messages on file opening
x86/vdso2c: Convert iterator to unsigned
x86/vdso/Makefile: Add vobjs32
x86/vdso: Restrict splitting VVAR VMA
x86/vdso: Rename vdso_image {.data=>.text}
x86/vdso: Allocate timens vdso
x86/vdso: Switch image on setns()/clone()
x86/vdso2c: Process jump tables
posix-clocks: Add align for timens_offsets
selftest/timens: Add Time Namespace test for supported clocks
selftest/timens: Add procfs selftest
MAINTAINERS | 3 +
arch/Kconfig | 5 +
arch/x86/Kconfig | 1 +
arch/x86/entry/vdso/Makefile | 15 +-
arch/x86/entry/vdso/vdso-layout.lds.S | 10 +-
arch/x86/entry/vdso/vdso2c.c | 7 +-
arch/x86/entry/vdso/vdso2c.h | 22 +-
arch/x86/entry/vdso/vma.c | 177 +++++++-
arch/x86/include/asm/jump_label.h | 14 +
arch/x86/include/asm/vdso.h | 14 +-
arch/x86/kernel/jump_label.c | 14 +
fs/proc/base.c | 95 +++++
fs/proc/namespaces.c | 4 +
fs/proc/uptime.c | 3 +
fs/timerfd.c | 3 +
include/linux/hrtimer.h | 2 +-
include/linux/jump_label.h | 8 +
include/linux/nsproxy.h | 2 +
include/linux/posix-timers.h | 3 +
include/linux/proc_ns.h | 3 +
include/linux/time_namespace.h | 114 ++++++
include/linux/timens_offsets.h | 18 +
include/linux/user_namespace.h | 1 +
include/uapi/linux/sched.h | 6 +
init/Kconfig | 9 +
kernel/Makefile | 1 +
kernel/fork.c | 16 +-
kernel/nsproxy.c | 41 +-
kernel/time/alarmtimer.c | 68 ++-
kernel/time/hrtimer.c | 8 +-
kernel/time/posix-clock.c | 8 +-
kernel/time/posix-cpu-timers.c | 32 +-
kernel/time/posix-stubs.c | 15 +-
kernel/time/posix-timers.c | 88 ++--
kernel/time/posix-timers.h | 7 +-
kernel/time_namespace.c | 387 ++++++++++++++++++
lib/vdso/gettimeofday.c | 53 +++
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/timens/.gitignore | 8 +
tools/testing/selftests/timens/Makefile | 12 +
.../selftests/timens/clock_nanosleep.c | 102 +++++
tools/testing/selftests/timens/config | 1 +
tools/testing/selftests/timens/exec.c | 93 +++++
tools/testing/selftests/timens/gettime_perf.c | 101 +++++
.../selftests/timens/gettime_perf_cold.c | 160 ++++++++
tools/testing/selftests/timens/log.h | 26 ++
tools/testing/selftests/timens/procfs.c | 144 +++++++
tools/testing/selftests/timens/timens.c | 185 +++++++++
tools/testing/selftests/timens/timens.h | 63 +++
tools/testing/selftests/timens/timer.c | 118 ++++++
tools/testing/selftests/timens/timerfd.c | 129 ++++++
51 files changed, 2305 insertions(+), 115 deletions(-)
create mode 100644 include/linux/time_namespace.h
create mode 100644 include/linux/timens_offsets.h
create mode 100644 kernel/time_namespace.c
create mode 100644 tools/testing/selftests/timens/.gitignore
create mode 100644 tools/testing/selftests/timens/Makefile
create mode 100644 tools/testing/selftests/timens/clock_nanosleep.c
create mode 100644 tools/testing/selftests/timens/config
create mode 100644 tools/testing/selftests/timens/exec.c
create mode 100644 tools/testing/selftests/timens/gettime_perf.c
create mode 100644 tools/testing/selftests/timens/gettime_perf_cold.c
create mode 100644 tools/testing/selftests/timens/log.h
create mode 100644 tools/testing/selftests/timens/procfs.c
create mode 100644 tools/testing/selftests/timens/timens.c
create mode 100644 tools/testing/selftests/timens/timens.h
create mode 100644 tools/testing/selftests/timens/timer.c
create mode 100644 tools/testing/selftests/timens/timerfd.c
--
2.22.0
^ permalink raw reply [flat|nested] 87+ messages in thread* [PATCHv6 01/36] ns: Introduce Time Namespace
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
2019-08-15 17:19 ` Thomas Gleixner
-1 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@openvz.org>
Time Namespace isolates clock values.
The kernel provides access to several clocks CLOCK_REALTIME,
CLOCK_MONOTONIC, CLOCK_BOOTTIME, etc.
CLOCK_REALTIME
System-wide clock that measures real (i.e., wall-clock) time.
CLOCK_MONOTONIC
Clock that cannot be set and represents monotonic time since
some unspecified starting point.
CLOCK_BOOTTIME
Identical to CLOCK_MONOTONIC, except it also includes any time
that the system is suspended.
For many users, the time namespace means the ability to changes date and
time in a container (CLOCK_REALTIME).
But in a context of the checkpoint/restore functionality, monotonic and
bootime clocks become interesting. Both clocks are monotonic with
unspecified staring points. These clocks are widely used to measure time
slices and set timers. After restoring or migrating processes, we have to
guarantee that they never go backward. In an ideal case, the behavior of
these clocks should be the same as for a case when a whole system is
suspended. All this means that we need to be able to set CLOCK_MONOTONIC
and CLOCK_BOOTTIME clocks, what can be done by adding per-namespace
offsets for clocks.
A time namespace is similar to a pid namespace in a way how it is
created: unshare(CLONE_NEWTIME) system call creates a new time namespace,
but doesn't set it to the current process. Then all children of
the process will be born in the new time namespace, or a process can
use the setns() system call to join a namespace.
This scheme allows setting clock offsets for a namespace, before any
processes appear in it.
All available clone flags have been used, so CLONE_NEWTIME uses the
highest bit of CSIGNAL. It means that we can use it with the unshare
system call only. Rith now, this works for us, because time namespace
offsets can be set only when a new time namespace is not populated. In a
future, we will have the clone3 system call [1] which will allow to use
the CSIGNAL mask for clone flags.
[1]: httmps://lkml.kernel.org/r/20190604160944.4058-1-christian@brauner.io
Link: https://criu.org/Time_namespace
Link: https://lists.openvz.org/pipermail/criu/2018-June/041504.html
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
MAINTAINERS | 2 +
fs/proc/namespaces.c | 4 +
include/linux/nsproxy.h | 2 +
include/linux/proc_ns.h | 3 +
include/linux/time_namespace.h | 69 +++++++++++
include/linux/user_namespace.h | 1 +
include/uapi/linux/sched.h | 6 +
init/Kconfig | 7 ++
kernel/Makefile | 1 +
kernel/fork.c | 16 ++-
kernel/nsproxy.c | 41 +++++--
kernel/time_namespace.c | 217 +++++++++++++++++++++++++++++++++
12 files changed, 359 insertions(+), 10 deletions(-)
create mode 100644 include/linux/time_namespace.h
create mode 100644 kernel/time_namespace.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 420567d1519a..97b7737f5aba 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12898,6 +12898,8 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
S: Maintained
F: fs/timerfd.c
F: include/linux/timer*
+F: include/linux/time_namespace.h
+F: kernel/time_namespace.c
F: kernel/time/*timer*
POWER MANAGEMENT CORE
diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index dd2b35f78b09..8b5c720fe5d7 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -33,6 +33,10 @@ static const struct proc_ns_operations *ns_entries[] = {
#ifdef CONFIG_CGROUPS
&cgroupns_operations,
#endif
+#ifdef CONFIG_TIME_NS
+ &timens_operations,
+ &timens_for_children_operations,
+#endif
};
static const char *proc_ns_get_link(struct dentry *dentry,
diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h
index 2ae1b1a4d84d..074f395b9ad2 100644
--- a/include/linux/nsproxy.h
+++ b/include/linux/nsproxy.h
@@ -35,6 +35,8 @@ struct nsproxy {
struct mnt_namespace *mnt_ns;
struct pid_namespace *pid_ns_for_children;
struct net *net_ns;
+ struct time_namespace *time_ns;
+ struct time_namespace *time_ns_for_children;
struct cgroup_namespace *cgroup_ns;
};
extern struct nsproxy init_nsproxy;
diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
index d31cb6215905..d312e6281e69 100644
--- a/include/linux/proc_ns.h
+++ b/include/linux/proc_ns.h
@@ -32,6 +32,8 @@ extern const struct proc_ns_operations pidns_for_children_operations;
extern const struct proc_ns_operations userns_operations;
extern const struct proc_ns_operations mntns_operations;
extern const struct proc_ns_operations cgroupns_operations;
+extern const struct proc_ns_operations timens_operations;
+extern const struct proc_ns_operations timens_for_children_operations;
/*
* We always define these enumerators
@@ -43,6 +45,7 @@ enum {
PROC_USER_INIT_INO = 0xEFFFFFFDU,
PROC_PID_INIT_INO = 0xEFFFFFFCU,
PROC_CGROUP_INIT_INO = 0xEFFFFFFBU,
+ PROC_TIME_INIT_INO = 0xEFFFFFFAU,
};
#ifdef CONFIG_PROC_FS
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
new file mode 100644
index 000000000000..9507ed7072fe
--- /dev/null
+++ b/include/linux/time_namespace.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TIMENS_H
+#define _LINUX_TIMENS_H
+
+
+#include <linux/sched.h>
+#include <linux/kref.h>
+#include <linux/nsproxy.h>
+#include <linux/ns_common.h>
+#include <linux/err.h>
+
+struct user_namespace;
+extern struct user_namespace init_user_ns;
+
+struct time_namespace {
+ struct kref kref;
+ struct user_namespace *user_ns;
+ struct ucounts *ucounts;
+ struct ns_common ns;
+ struct timens_offsets *offsets;
+ bool initialized;
+} __randomize_layout;
+extern struct time_namespace init_time_ns;
+
+#ifdef CONFIG_TIME_NS
+static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
+{
+ kref_get(&ns->kref);
+ return ns;
+}
+
+extern struct time_namespace *copy_time_ns(unsigned long flags,
+ struct user_namespace *user_ns, struct time_namespace *old_ns);
+extern void free_time_ns(struct kref *kref);
+extern int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
+
+static inline void put_time_ns(struct time_namespace *ns)
+{
+ kref_put(&ns->kref, free_time_ns);
+}
+
+
+#else
+static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
+{
+ return NULL;
+}
+
+static inline void put_time_ns(struct time_namespace *ns)
+{
+}
+
+static inline struct time_namespace *copy_time_ns(unsigned long flags,
+ struct user_namespace *user_ns, struct time_namespace *old_ns)
+{
+ if (flags & CLONE_NEWTIME)
+ return ERR_PTR(-EINVAL);
+
+ return old_ns;
+}
+
+static inline int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
+{
+ return 0;
+}
+
+#endif
+
+#endif /* _LINUX_TIMENS_H */
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index fb9f4f799554..6ef1c7109fc4 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -45,6 +45,7 @@ enum ucount_type {
UCOUNT_NET_NAMESPACES,
UCOUNT_MNT_NAMESPACES,
UCOUNT_CGROUP_NAMESPACES,
+ UCOUNT_TIME_NAMESPACES,
#ifdef CONFIG_INOTIFY_USER
UCOUNT_INOTIFY_INSTANCES,
UCOUNT_INOTIFY_WATCHES,
diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h
index e1ce103a2c47..f3f5c496ce44 100644
--- a/include/uapi/linux/sched.h
+++ b/include/uapi/linux/sched.h
@@ -33,6 +33,12 @@
#define CLONE_NEWNET 0x40000000 /* New network namespace */
#define CLONE_IO 0x80000000 /* Clone io context */
+/*
+ * cloning flags intersect with CSIGNAL so can be used with unshare and clone3
+ * syscalls only:
+ */
+#define CLONE_NEWTIME 0x00000080 /* New time namespace */
+
/*
* Arguments for the clone3 syscall
*/
diff --git a/init/Kconfig b/init/Kconfig
index befcbb43cd2a..525dc3ed86c4 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1072,6 +1072,13 @@ config UTS_NS
In this namespace tasks see different info provided with the
uname() system call
+config TIME_NS
+ bool "TIME namespace"
+ default y
+ help
+ In this namespace boottime and monotonic clocks can be set.
+ The time will keep going with the same pace.
+
config IPC_NS
bool "IPC namespace"
depends on (SYSVIPC || POSIX_MQUEUE)
diff --git a/kernel/Makefile b/kernel/Makefile
index e4dc0e7907b5..d0b48c6ed171 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
obj-$(CONFIG_COMPAT) += compat.o
obj-$(CONFIG_CGROUPS) += cgroup/
obj-$(CONFIG_UTS_NS) += utsname.o
+obj-$(CONFIG_TIME_NS) += time_namespace.o
obj-$(CONFIG_USER_NS) += user_namespace.o
obj-$(CONFIG_PID_NS) += pid_namespace.o
obj-$(CONFIG_IKCONFIG) += configs.o
diff --git a/kernel/fork.c b/kernel/fork.c
index b84534b6a463..23eed98b68bb 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1804,6 +1804,7 @@ static __latent_entropy struct task_struct *copy_process(
struct multiprocess_signals delayed;
struct file *pidfile = NULL;
u64 clone_flags = args->flags;
+ struct nsproxy *nsp = current->nsproxy;
/*
* Don't allow sharing the root directory with processes in a different
@@ -1846,8 +1847,16 @@ static __latent_entropy struct task_struct *copy_process(
*/
if (clone_flags & CLONE_THREAD) {
if ((clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) ||
- (task_active_pid_ns(current) !=
- current->nsproxy->pid_ns_for_children))
+ (task_active_pid_ns(current) != nsp->pid_ns_for_children))
+ return ERR_PTR(-EINVAL);
+ }
+
+ /*
+ * If the new process will be in a different time namespace
+ * do not allow it to share VM or a thread group with the forking task.
+ */
+ if (clone_flags & (CLONE_THREAD | CLONE_VM)) {
+ if (nsp->time_ns != nsp->time_ns_for_children)
return ERR_PTR(-EINVAL);
}
@@ -2739,7 +2748,8 @@ static int check_unshare_flags(unsigned long unshare_flags)
if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET|
- CLONE_NEWUSER|CLONE_NEWPID|CLONE_NEWCGROUP))
+ CLONE_NEWUSER|CLONE_NEWPID|CLONE_NEWCGROUP|
+ CLONE_NEWTIME))
return -EINVAL;
/*
* Not implemented, but pretend it works if there is nothing
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index c815f58e6bc0..ed9882108cd2 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -18,6 +18,7 @@
#include <linux/pid_namespace.h>
#include <net/net_namespace.h>
#include <linux/ipc_namespace.h>
+#include <linux/time_namespace.h>
#include <linux/proc_ns.h>
#include <linux/file.h>
#include <linux/syscalls.h>
@@ -40,6 +41,10 @@ struct nsproxy init_nsproxy = {
#ifdef CONFIG_CGROUPS
.cgroup_ns = &init_cgroup_ns,
#endif
+#ifdef CONFIG_TIME_NS
+ .time_ns = &init_time_ns,
+ .time_ns_for_children = &init_time_ns,
+#endif
};
static inline struct nsproxy *create_nsproxy(void)
@@ -106,8 +111,18 @@ static struct nsproxy *create_new_namespaces(unsigned long flags,
goto out_net;
}
+ new_nsp->time_ns_for_children = copy_time_ns(flags, user_ns,
+ tsk->nsproxy->time_ns_for_children);
+ if (IS_ERR(new_nsp->time_ns_for_children)) {
+ err = PTR_ERR(new_nsp->time_ns_for_children);
+ goto out_time;
+ }
+ new_nsp->time_ns = get_time_ns(tsk->nsproxy->time_ns);
+
return new_nsp;
+out_time:
+ put_net(new_nsp->net_ns);
out_net:
put_cgroup_ns(new_nsp->cgroup_ns);
out_cgroup:
@@ -136,15 +151,16 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
struct nsproxy *old_ns = tsk->nsproxy;
struct user_namespace *user_ns = task_cred_xxx(tsk, user_ns);
struct nsproxy *new_ns;
+ int ret;
if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
CLONE_NEWPID | CLONE_NEWNET |
- CLONE_NEWCGROUP)))) {
- get_nsproxy(old_ns);
- return 0;
- }
-
- if (!ns_capable(user_ns, CAP_SYS_ADMIN))
+ CLONE_NEWCGROUP | CLONE_NEWTIME)))) {
+ if (likely(old_ns->time_ns_for_children == old_ns->time_ns)) {
+ get_nsproxy(old_ns);
+ return 0;
+ }
+ } else if (!ns_capable(user_ns, CAP_SYS_ADMIN))
return -EPERM;
/*
@@ -162,6 +178,12 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
if (IS_ERR(new_ns))
return PTR_ERR(new_ns);
+ ret = timens_on_fork(new_ns, tsk);
+ if (ret) {
+ free_nsproxy(new_ns);
+ return ret;
+ }
+
tsk->nsproxy = new_ns;
return 0;
}
@@ -176,6 +198,10 @@ void free_nsproxy(struct nsproxy *ns)
put_ipc_ns(ns->ipc_ns);
if (ns->pid_ns_for_children)
put_pid_ns(ns->pid_ns_for_children);
+ if (ns->time_ns)
+ put_time_ns(ns->time_ns);
+ if (ns->time_ns_for_children)
+ put_time_ns(ns->time_ns_for_children);
put_cgroup_ns(ns->cgroup_ns);
put_net(ns->net_ns);
kmem_cache_free(nsproxy_cachep, ns);
@@ -192,7 +218,8 @@ int unshare_nsproxy_namespaces(unsigned long unshare_flags,
int err = 0;
if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
- CLONE_NEWNET | CLONE_NEWPID | CLONE_NEWCGROUP)))
+ CLONE_NEWNET | CLONE_NEWPID | CLONE_NEWCGROUP |
+ CLONE_NEWTIME)))
return 0;
user_ns = new_cred ? new_cred->user_ns : current_user_ns();
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
new file mode 100644
index 000000000000..8fd8384b7261
--- /dev/null
+++ b/kernel/time_namespace.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Andrei Vagin <avagin@openvz.org>
+ * Author: Dmitry Safonov <dima@arista.com>
+ */
+
+#include <linux/time_namespace.h>
+#include <linux/user_namespace.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/task.h>
+#include <linux/proc_ns.h>
+#include <linux/export.h>
+#include <linux/time.h>
+#include <linux/slab.h>
+#include <linux/cred.h>
+#include <linux/err.h>
+
+static struct ucounts *inc_time_namespaces(struct user_namespace *ns)
+{
+ return inc_ucount(ns, current_euid(), UCOUNT_TIME_NAMESPACES);
+}
+
+static void dec_time_namespaces(struct ucounts *ucounts)
+{
+ dec_ucount(ucounts, UCOUNT_TIME_NAMESPACES);
+}
+
+static struct time_namespace *create_time_ns(void)
+{
+ struct time_namespace *time_ns;
+
+ time_ns = kmalloc(sizeof(struct time_namespace), GFP_KERNEL);
+ if (time_ns) {
+ kref_init(&time_ns->kref);
+ time_ns->initialized = false;
+ }
+ return time_ns;
+}
+
+/*
+ * Clone a new ns copying @old_ns, setting refcount to 1
+ * @old_ns: namespace to clone
+ * Return the new ns or ERR_PTR.
+ */
+static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
+ struct time_namespace *old_ns)
+{
+ struct time_namespace *ns;
+ struct ucounts *ucounts;
+ int err;
+
+ err = -ENOSPC;
+ ucounts = inc_time_namespaces(user_ns);
+ if (!ucounts)
+ goto fail;
+
+ err = -ENOMEM;
+ ns = create_time_ns();
+ if (!ns)
+ goto fail_dec;
+
+ err = ns_alloc_inum(&ns->ns);
+ if (err)
+ goto fail_free;
+
+ ns->ucounts = ucounts;
+ ns->ns.ops = &timens_operations;
+ ns->user_ns = get_user_ns(user_ns);
+ return ns;
+
+fail_free:
+ kfree(ns);
+fail_dec:
+ dec_time_namespaces(ucounts);
+fail:
+ return ERR_PTR(err);
+}
+
+/*
+ * Add a reference to old_ns, or clone it if @flags specify CLONE_NEWTIME.
+ * In latter case, changes to the time of this process won't be seen by parent,
+ * and vice versa.
+ */
+struct time_namespace *copy_time_ns(unsigned long flags,
+ struct user_namespace *user_ns, struct time_namespace *old_ns)
+{
+ if (!(flags & CLONE_NEWTIME))
+ return get_time_ns(old_ns);
+
+ return clone_time_ns(user_ns, old_ns);
+}
+
+void free_time_ns(struct kref *kref)
+{
+ struct time_namespace *ns;
+
+ ns = container_of(kref, struct time_namespace, kref);
+ dec_time_namespaces(ns->ucounts);
+ put_user_ns(ns->user_ns);
+ ns_free_inum(&ns->ns);
+ kfree(ns);
+}
+
+static struct time_namespace *to_time_ns(struct ns_common *ns)
+{
+ return container_of(ns, struct time_namespace, ns);
+}
+
+static struct ns_common *timens_get(struct task_struct *task)
+{
+ struct time_namespace *ns = NULL;
+ struct nsproxy *nsproxy;
+
+ task_lock(task);
+ nsproxy = task->nsproxy;
+ if (nsproxy) {
+ ns = nsproxy->time_ns;
+ get_time_ns(ns);
+ }
+ task_unlock(task);
+
+ return ns ? &ns->ns : NULL;
+}
+
+static struct ns_common *timens_for_children_get(struct task_struct *task)
+{
+ struct time_namespace *ns = NULL;
+ struct nsproxy *nsproxy;
+
+ task_lock(task);
+ nsproxy = task->nsproxy;
+ if (nsproxy) {
+ ns = nsproxy->time_ns_for_children;
+ get_time_ns(ns);
+ }
+ task_unlock(task);
+
+ return ns ? &ns->ns : NULL;
+}
+
+static void timens_put(struct ns_common *ns)
+{
+ put_time_ns(to_time_ns(ns));
+}
+
+static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
+{
+ struct time_namespace *ns = to_time_ns(new);
+
+ if (!current_is_single_threaded())
+ return -EUSERS;
+
+ if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) ||
+ !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
+ return -EPERM;
+
+ get_time_ns(ns);
+ get_time_ns(ns);
+ put_time_ns(nsproxy->time_ns);
+ put_time_ns(nsproxy->time_ns_for_children);
+ nsproxy->time_ns = ns;
+ nsproxy->time_ns_for_children = ns;
+ ns->initialized = true;
+ return 0;
+}
+
+int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
+{
+ struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
+ struct time_namespace *ns = to_time_ns(nsc);
+
+ if (nsproxy->time_ns == nsproxy->time_ns_for_children)
+ return 0;
+
+ get_time_ns(ns);
+ put_time_ns(nsproxy->time_ns);
+ nsproxy->time_ns = ns;
+ ns->initialized = true;
+
+ return 0;
+}
+
+static struct user_namespace *timens_owner(struct ns_common *ns)
+{
+ return to_time_ns(ns)->user_ns;
+}
+
+const struct proc_ns_operations timens_operations = {
+ .name = "time",
+ .type = CLONE_NEWTIME,
+ .get = timens_get,
+ .put = timens_put,
+ .install = timens_install,
+ .owner = timens_owner,
+};
+
+const struct proc_ns_operations timens_for_children_operations = {
+ .name = "time_for_children",
+ .type = CLONE_NEWTIME,
+ .get = timens_for_children_get,
+ .put = timens_put,
+ .install = timens_install,
+ .owner = timens_owner,
+};
+
+struct time_namespace init_time_ns = {
+ .kref = KREF_INIT(3),
+ .user_ns = &init_user_ns,
+ .ns.inum = PROC_TIME_INIT_INO,
+ .ns.ops = &timens_operations,
+};
+
+static int __init time_ns_init(void)
+{
+ return 0;
+}
+subsys_initcall(time_ns_init);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 01/36] ns: Introduce Time Namespace
2019-08-15 16:38 ` [PATCHv6 01/36] ns: " Dmitry Safonov
@ 2019-08-15 17:19 ` Thomas Gleixner
2019-08-16 6:11 ` Andrei Vagin
0 siblings, 1 reply; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 17:19 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
Dmitry,
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 420567d1519a..97b7737f5aba 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -12898,6 +12898,8 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
> S: Maintained
> F: fs/timerfd.c
> F: include/linux/timer*
> +F: include/linux/time_namespace.h
> +F: kernel/time_namespace.c
Shouldn't this be kernel/time/namespace.c so all that stuff is lumped
together. No strong opinion though.
> +++ b/kernel/time_namespace.c
> +static struct ucounts *inc_time_namespaces(struct user_namespace *ns)
> +{
> + return inc_ucount(ns, current_euid(), UCOUNT_TIME_NAMESPACES);
> +}
> +
> +static void dec_time_namespaces(struct ucounts *ucounts)
> +{
> + dec_ucount(ucounts, UCOUNT_TIME_NAMESPACES);
> +}
> +
> +static struct time_namespace *create_time_ns(void)
> +{
> + struct time_namespace *time_ns;
> +
> + time_ns = kmalloc(sizeof(struct time_namespace), GFP_KERNEL);
Shouldn't this use kzalloc()? There are tons of members in that struct.
> + if (time_ns) {
> + kref_init(&time_ns->kref);
> + time_ns->initialized = false;
And you spare this one.
> + }
> + return time_ns;
> +}
> +
> +/*
> + * Clone a new ns copying @old_ns, setting refcount to 1
> + * @old_ns: namespace to clone
> + * Return the new ns or ERR_PTR.
If you use kernel-doc style then please use te proper syntax
/*
* clone_time_ns - Clone a time namespace
* @old_ns: Namespace to clone
*
* Clone @old_ns and set the clone refcount to 1
*
* Return: The new namespace or ERR_PTR.
*/
> + */
> +static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
> + struct time_namespace *old_ns)
> +{
> + struct time_namespace *ns;
> + struct ucounts *ucounts;
> + int err;
> +
> + err = -ENOSPC;
> + ucounts = inc_time_namespaces(user_ns);
> + if (!ucounts)
> + goto fail;
> +
> + err = -ENOMEM;
> + ns = create_time_ns();
> + if (!ns)
> + goto fail_dec;
> +
> + err = ns_alloc_inum(&ns->ns);
> + if (err)
> + goto fail_free;
> +
> + ns->ucounts = ucounts;
> + ns->ns.ops = &timens_operations;
> + ns->user_ns = get_user_ns(user_ns);
> + return ns;
> +
> +fail_free:
> + kfree(ns);
> +fail_dec:
> + dec_time_namespaces(ucounts);
> +fail:
> + return ERR_PTR(err);
> +}
> +
> +/*
> + * Add a reference to old_ns, or clone it if @flags specify CLONE_NEWTIME.
> + * In latter case, changes to the time of this process won't be seen by parent,
> + * and vice versa.
Ditto
> + */
> +struct time_namespace *copy_time_ns(unsigned long flags,
> + struct user_namespace *user_ns, struct time_namespace *old_ns)
> +{
> + if (!(flags & CLONE_NEWTIME))
> + return get_time_ns(old_ns);
> +
> + return clone_time_ns(user_ns, old_ns);
> +}
> +
> +void free_time_ns(struct kref *kref)
> +{
> + struct time_namespace *ns;
> +
> + ns = container_of(kref, struct time_namespace, kref);
> + dec_time_namespaces(ns->ucounts);
> + put_user_ns(ns->user_ns);
> + ns_free_inum(&ns->ns);
> + kfree(ns);
> +}
> +
> +static struct time_namespace *to_time_ns(struct ns_common *ns)
> +{
> + return container_of(ns, struct time_namespace, ns);
> +}
> +
> +static struct ns_common *timens_get(struct task_struct *task)
> +{
> + struct time_namespace *ns = NULL;
> + struct nsproxy *nsproxy;
> +
> + task_lock(task);
> + nsproxy = task->nsproxy;
> + if (nsproxy) {
> + ns = nsproxy->time_ns;
> + get_time_ns(ns);
> + }
> + task_unlock(task);
> +
> + return ns ? &ns->ns : NULL;
> +}
> +
> +static struct ns_common *timens_for_children_get(struct task_struct *task)
> +{
> + struct time_namespace *ns = NULL;
> + struct nsproxy *nsproxy;
> +
> + task_lock(task);
> + nsproxy = task->nsproxy;
> + if (nsproxy) {
> + ns = nsproxy->time_ns_for_children;
> + get_time_ns(ns);
> + }
> + task_unlock(task);
> +
> + return ns ? &ns->ns : NULL;
> +}
> +
> +static void timens_put(struct ns_common *ns)
> +{
> + put_time_ns(to_time_ns(ns));
> +}
> +
> +static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
> +{
> + struct time_namespace *ns = to_time_ns(new);
> +
> + if (!current_is_single_threaded())
> + return -EUSERS;
> +
> + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) ||
> + !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
> + return -EPERM;
> +
> + get_time_ns(ns);
> + get_time_ns(ns);
Why is this a double get?
> + put_time_ns(nsproxy->time_ns);
> + put_time_ns(nsproxy->time_ns_for_children);
> + nsproxy->time_ns = ns;
> + nsproxy->time_ns_for_children = ns;
> + ns->initialized = true;
> + return 0;
> +}
> +
> +int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
> +{
> + struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
> + struct time_namespace *ns = to_time_ns(nsc);
> +
> + if (nsproxy->time_ns == nsproxy->time_ns_for_children)
> + return 0;
> +
> + get_time_ns(ns);
> + put_time_ns(nsproxy->time_ns);
> + nsproxy->time_ns = ns;
> + ns->initialized = true;
Isn't that one initialized already?
> +
> + return 0;
> +}
> +
> +static struct user_namespace *timens_owner(struct ns_common *ns)
> +{
> + return to_time_ns(ns)->user_ns;
> +}
> +
> +const struct proc_ns_operations timens_operations = {
> + .name = "time",
> + .type = CLONE_NEWTIME,
> + .get = timens_get,
> + .put = timens_put,
> + .install = timens_install,
> + .owner = timens_owner,
> +};
> +
> +const struct proc_ns_operations timens_for_children_operations = {
> + .name = "time_for_children",
> + .type = CLONE_NEWTIME,
> + .get = timens_for_children_get,
> + .put = timens_put,
> + .install = timens_install,
> + .owner = timens_owner,
> +};
> +
> +struct time_namespace init_time_ns = {
> + .kref = KREF_INIT(3),
> + .user_ns = &init_user_ns,
> + .ns.inum = PROC_TIME_INIT_INO,
> + .ns.ops = &timens_operations,
> +};
Inconsisten formatting. The above static initializers are nicely
tabular. This on not.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 01/36] ns: Introduce Time Namespace
2019-08-15 17:19 ` Thomas Gleixner
@ 2019-08-16 6:11 ` Andrei Vagin
2019-08-16 6:34 ` Thomas Gleixner
0 siblings, 1 reply; 87+ messages in thread
From: Andrei Vagin @ 2019-08-16 6:11 UTC (permalink / raw)
To: Thomas Gleixner
Cc: Dmitry Safonov, linux-kernel, Dmitry Safonov, Andrei Vagin,
Adrian Reber, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, Aug 15, 2019 at 07:19:12PM +0200, Thomas Gleixner wrote:
> Dmitry,
>
> On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 420567d1519a..97b7737f5aba 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -12898,6 +12898,8 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
> > S: Maintained
> > F: fs/timerfd.c
> > F: include/linux/timer*
> > +F: include/linux/time_namespace.h
> > +F: kernel/time_namespace.c
>
> Shouldn't this be kernel/time/namespace.c so all that stuff is lumped
> together. No strong opinion though.
Sure, we can move this in kernel/time. I don't remember why I decided to
place it in kernel/.
>
> > +++ b/kernel/time_namespace.c
> > +static struct ucounts *inc_time_namespaces(struct user_namespace *ns)
> > +{
> > + return inc_ucount(ns, current_euid(), UCOUNT_TIME_NAMESPACES);
> > +}
> > +
> > +static void dec_time_namespaces(struct ucounts *ucounts)
> > +{
> > + dec_ucount(ucounts, UCOUNT_TIME_NAMESPACES);
> > +}
> > +
> > +static struct time_namespace *create_time_ns(void)
> > +{
> > + struct time_namespace *time_ns;
> > +
> > + time_ns = kmalloc(sizeof(struct time_namespace), GFP_KERNEL);
>
> Shouldn't this use kzalloc()? There are tons of members in that struct.
I don't think so. All of other members are initialized in clone_time_ns.
Maybe we don't need this helper. When I wrote this code, I looked at
kernel/utsname.c. I will think what we can do here to make this code
more clear.
>
> > + if (time_ns) {
> > + kref_init(&time_ns->kref);
> > + time_ns->initialized = false;
>
> And you spare this one.
This one should be initialized in clone_time_ns too.
>
> > + }
> > + return time_ns;
> > +}
> > +
> > +/*
> > + * Clone a new ns copying @old_ns, setting refcount to 1
> > + * @old_ns: namespace to clone
> > + * Return the new ns or ERR_PTR.
>
> If you use kernel-doc style then please use te proper syntax
>
> /*
> * clone_time_ns - Clone a time namespace
> * @old_ns: Namespace to clone
> *
> * Clone @old_ns and set the clone refcount to 1
> *
> * Return: The new namespace or ERR_PTR.
> */
Will fix. Thanks!
>
> > + */
> > +static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
> > + struct time_namespace *old_ns)
> > +{
> > + struct time_namespace *ns;
> > + struct ucounts *ucounts;
> > + int err;
> > +
> > + err = -ENOSPC;
> > + ucounts = inc_time_namespaces(user_ns);
> > + if (!ucounts)
> > + goto fail;
> > +
> > + err = -ENOMEM;
> > + ns = create_time_ns();
> > + if (!ns)
> > + goto fail_dec;
> > +
> > + err = ns_alloc_inum(&ns->ns);
> > + if (err)
> > + goto fail_free;
> > +
> > + ns->ucounts = ucounts;
> > + ns->ns.ops = &timens_operations;
> > + ns->user_ns = get_user_ns(user_ns);
> > + return ns;
> > +
> > +fail_free:
> > + kfree(ns);
> > +fail_dec:
> > + dec_time_namespaces(ucounts);
> > +fail:
> > + return ERR_PTR(err);
> > +}
> > +
> > +/*
> > + * Add a reference to old_ns, or clone it if @flags specify CLONE_NEWTIME.
> > + * In latter case, changes to the time of this process won't be seen by parent,
> > + * and vice versa.
>
> Ditto
Will fix.
>
> > + */
> > +struct time_namespace *copy_time_ns(unsigned long flags,
> > + struct user_namespace *user_ns, struct time_namespace *old_ns)
> > +{
> > + if (!(flags & CLONE_NEWTIME))
> > + return get_time_ns(old_ns);
> > +
> > + return clone_time_ns(user_ns, old_ns);
> > +}
> > +
> > +void free_time_ns(struct kref *kref)
> > +{
> > + struct time_namespace *ns;
> > +
> > + ns = container_of(kref, struct time_namespace, kref);
> > + dec_time_namespaces(ns->ucounts);
> > + put_user_ns(ns->user_ns);
> > + ns_free_inum(&ns->ns);
> > + kfree(ns);
> > +}
> > +
> > +static struct time_namespace *to_time_ns(struct ns_common *ns)
> > +{
> > + return container_of(ns, struct time_namespace, ns);
> > +}
> > +
> > +static struct ns_common *timens_get(struct task_struct *task)
> > +{
> > + struct time_namespace *ns = NULL;
> > + struct nsproxy *nsproxy;
> > +
> > + task_lock(task);
> > + nsproxy = task->nsproxy;
> > + if (nsproxy) {
> > + ns = nsproxy->time_ns;
> > + get_time_ns(ns);
> > + }
> > + task_unlock(task);
> > +
> > + return ns ? &ns->ns : NULL;
> > +}
> > +
> > +static struct ns_common *timens_for_children_get(struct task_struct *task)
> > +{
> > + struct time_namespace *ns = NULL;
> > + struct nsproxy *nsproxy;
> > +
> > + task_lock(task);
> > + nsproxy = task->nsproxy;
> > + if (nsproxy) {
> > + ns = nsproxy->time_ns_for_children;
> > + get_time_ns(ns);
> > + }
> > + task_unlock(task);
> > +
> > + return ns ? &ns->ns : NULL;
> > +}
> > +
> > +static void timens_put(struct ns_common *ns)
> > +{
> > + put_time_ns(to_time_ns(ns));
> > +}
> > +
> > +static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
> > +{
> > + struct time_namespace *ns = to_time_ns(new);
> > +
> > + if (!current_is_single_threaded())
> > + return -EUSERS;
> > +
> > + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) ||
> > + !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
> > + return -EPERM;
> > +
> > + get_time_ns(ns);
> > + get_time_ns(ns);
>
> Why is this a double get?
Because we change nsproxy->time_ns and nsproxy->time_ns_for_children.
Probably, I need to reorgonize the code this way:
get_time_ns(ns);
put_time_ns(nsproxy->time_ns);
nsproxy->time_ns = ns;
get_time_ns(ns);
put_time_ns(nsproxy->time_ns_for_children);
nsproxy->time_ns_for_children = ns;
>
> > + put_time_ns(nsproxy->time_ns);
> > + put_time_ns(nsproxy->time_ns_for_children);
> > + nsproxy->time_ns = ns;
> > + nsproxy->time_ns_for_children = ns;
> > + ns->initialized = true;
> > + return 0;
> > +}
> > +
> > +int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
> > +{
> > + struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
> > + struct time_namespace *ns = to_time_ns(nsc);
> > +
> > + if (nsproxy->time_ns == nsproxy->time_ns_for_children)
> > + return 0;
> > +
> > + get_time_ns(ns);
> > + put_time_ns(nsproxy->time_ns);
> > + nsproxy->time_ns = ns;
> > + ns->initialized = true;
>
> Isn't that one initialized already?
When we discussed time namespaces last year, we decided that clock
offsets can be set only before any task enters a namespace.
When a namespace is created, ns->initialized is set to false. When a
task enters the namespace, ns->initialized is set to true.
Namespace clock offsets can be changed only if ns->initialized is false.
A new task can be forked to a specified time namespace or it can call
setns, so we set ns->initialized to true in timens_on_fork and
timens_install.
>
> > +
> > + return 0;
> > +}
> > +
> > +static struct user_namespace *timens_owner(struct ns_common *ns)
> > +{
> > + return to_time_ns(ns)->user_ns;
> > +}
> > +
> > +const struct proc_ns_operations timens_operations = {
> > + .name = "time",
> > + .type = CLONE_NEWTIME,
> > + .get = timens_get,
> > + .put = timens_put,
> > + .install = timens_install,
> > + .owner = timens_owner,
> > +};
> > +
> > +const struct proc_ns_operations timens_for_children_operations = {
> > + .name = "time_for_children",
> > + .type = CLONE_NEWTIME,
> > + .get = timens_for_children_get,
> > + .put = timens_put,
> > + .install = timens_install,
> > + .owner = timens_owner,
> > +};
> > +
> > +struct time_namespace init_time_ns = {
> > + .kref = KREF_INIT(3),
> > + .user_ns = &init_user_ns,
> > + .ns.inum = PROC_TIME_INIT_INO,
> > + .ns.ops = &timens_operations,
> > +};
>
> Inconsisten formatting. The above static initializers are nicely
> tabular. This on not.
Will fix. Thanks.
Thanks,
Andrei
>
> Thanks,
>
> tglx
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 01/36] ns: Introduce Time Namespace
2019-08-16 6:11 ` Andrei Vagin
@ 2019-08-16 6:34 ` Thomas Gleixner
0 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-16 6:34 UTC (permalink / raw)
To: Andrei Vagin
Cc: Dmitry Safonov, linux-kernel, Dmitry Safonov, Andrei Vagin,
Adrian Reber, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
Andrei,
On Thu, 15 Aug 2019, Andrei Vagin wrote:
> On Thu, Aug 15, 2019 at 07:19:12PM +0200, Thomas Gleixner wrote:
> > > +static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
> > > +{
> > > + struct time_namespace *ns = to_time_ns(new);
> > > +
> > > + if (!current_is_single_threaded())
> > > + return -EUSERS;
> > > +
> > > + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) ||
> > > + !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
> > > + return -EPERM;
> > > +
> > > + get_time_ns(ns);
> > > + get_time_ns(ns);
> >
> > Why is this a double get?
>
> Because we change nsproxy->time_ns and nsproxy->time_ns_for_children.
>
> Probably, I need to reorgonize the code this way:
>
> get_time_ns(ns);
> put_time_ns(nsproxy->time_ns);
> nsproxy->time_ns = ns;
>
> get_time_ns(ns);
> put_time_ns(nsproxy->time_ns_for_children);
> nsproxy->time_ns_for_children = ns;
That's better. A few comments about refcounting might be useful as well.
> > > + put_time_ns(nsproxy->time_ns);
> > > + put_time_ns(nsproxy->time_ns_for_children);
> > > + nsproxy->time_ns = ns;
> > > + nsproxy->time_ns_for_children = ns;
> > > + ns->initialized = true;
> > > + return 0;
> > > +}
> > > +
> > > +int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
> > > +{
> > > + struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
> > > + struct time_namespace *ns = to_time_ns(nsc);
> > > +
> > > + if (nsproxy->time_ns == nsproxy->time_ns_for_children)
> > > + return 0;
Doesn't this need to take a refcount on fork? Maybe not, but see below.
> > > +
> > > + get_time_ns(ns);
> > > + put_time_ns(nsproxy->time_ns);
> > > + nsproxy->time_ns = ns;
> > > + ns->initialized = true;
> >
> > Isn't that one initialized already?
>
> When we discussed time namespaces last year, we decided that clock
> offsets can be set only before any task enters a namespace.
>
> When a namespace is created, ns->initialized is set to false. When a
> task enters the namespace, ns->initialized is set to true.
Right. I'm probably just hopelessly confused by this nsproxy->time_ns
vs. nsproxy->time_ns_for_children->ns thing.
> Namespace clock offsets can be changed only if ns->initialized is false.
>
> A new task can be forked to a specified time namespace or it can call
> setns, so we set ns->initialized to true in timens_on_fork and
> timens_install.
Some comments explaining that logic above would be really helpful.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 02/36] timens: Add timens_offsets
2019-08-15 16:38 ` Dmitry Safonov
(?)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
2019-08-15 17:21 ` Thomas Gleixner
-1 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@openvz.org>
Introduce offsets for time namespace. They will contain an adjustment
needed to convert clocks to/from host's.
Allocate one page for each time namespace that will be premapped into
userspace among vvar pages.
A new namespace is created with the same offsets as the time namespace
of the current process.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
MAINTAINERS | 1 +
include/linux/time_namespace.h | 18 ++++++++++++++++++
include/linux/timens_offsets.h | 10 ++++++++++
kernel/time_namespace.c | 16 ++++++++++++++--
4 files changed, 43 insertions(+), 2 deletions(-)
create mode 100644 include/linux/timens_offsets.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 97b7737f5aba..527aee1e616f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12899,6 +12899,7 @@ S: Maintained
F: fs/timerfd.c
F: include/linux/timer*
F: include/linux/time_namespace.h
+F: include/linux/timens_offsets.h
F: kernel/time_namespace.c
F: kernel/time/*timer*
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 9507ed7072fe..334c1a1c6607 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -8,6 +8,7 @@
#include <linux/nsproxy.h>
#include <linux/ns_common.h>
#include <linux/err.h>
+#include <linux/timens_offsets.h>
struct user_namespace;
extern struct user_namespace init_user_ns;
@@ -39,6 +40,21 @@ static inline void put_time_ns(struct time_namespace *ns)
kref_put(&ns->kref, free_time_ns);
}
+static inline void timens_add_monotonic(struct timespec64 *ts)
+{
+ struct timens_offsets *ns_offsets = current->nsproxy->time_ns->offsets;
+
+ if (ns_offsets)
+ *ts = timespec64_add(*ts, ns_offsets->monotonic);
+}
+
+static inline void timens_add_boottime(struct timespec64 *ts)
+{
+ struct timens_offsets *ns_offsets = current->nsproxy->time_ns->offsets;
+
+ if (ns_offsets)
+ *ts = timespec64_add(*ts, ns_offsets->boottime);
+}
#else
static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
@@ -64,6 +80,8 @@ static inline int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *ts
return 0;
}
+static inline void timens_add_monotonic(struct timespec64 *ts) {}
+static inline void timens_add_boottime(struct timespec64 *ts) {}
#endif
#endif /* _LINUX_TIMENS_H */
diff --git a/include/linux/timens_offsets.h b/include/linux/timens_offsets.h
new file mode 100644
index 000000000000..e93aabaa5e45
--- /dev/null
+++ b/include/linux/timens_offsets.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TIME_OFFSETS_H
+#define _LINUX_TIME_OFFSETS_H
+
+struct timens_offsets {
+ struct timespec64 monotonic;
+ struct timespec64 boottime;
+};
+
+#endif
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index 8fd8384b7261..394a9e168e7c 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -14,6 +14,7 @@
#include <linux/slab.h>
#include <linux/cred.h>
#include <linux/err.h>
+#include <linux/mm.h>
static struct ucounts *inc_time_namespaces(struct user_namespace *ns)
{
@@ -47,6 +48,7 @@ static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
{
struct time_namespace *ns;
struct ucounts *ucounts;
+ struct page *page;
int err;
err = -ENOSPC;
@@ -59,15 +61,24 @@ static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
if (!ns)
goto fail_dec;
+ page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!page)
+ goto fail_free;
+ ns->offsets = page_address(page);
+ if (old_ns->offsets)
+ memcpy(ns->offsets, old_ns->offsets, sizeof(struct timens_offsets));
+ BUILD_BUG_ON(sizeof(*ns->offsets) > PAGE_SIZE);
+
err = ns_alloc_inum(&ns->ns);
if (err)
- goto fail_free;
+ goto fail_page;
ns->ucounts = ucounts;
ns->ns.ops = &timens_operations;
ns->user_ns = get_user_ns(user_ns);
return ns;
-
+fail_page:
+ free_page((unsigned long)ns->offsets);
fail_free:
kfree(ns);
fail_dec:
@@ -95,6 +106,7 @@ void free_time_ns(struct kref *kref)
struct time_namespace *ns;
ns = container_of(kref, struct time_namespace, kref);
+ free_page((unsigned long)ns->offsets);
dec_time_namespaces(ns->ucounts);
put_user_ns(ns->user_ns);
ns_free_inum(&ns->ns);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 02/36] timens: Add timens_offsets
2019-08-15 16:38 ` [PATCHv6 02/36] timens: Add timens_offsets Dmitry Safonov
@ 2019-08-15 17:21 ` Thomas Gleixner
0 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 17:21 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> + page = alloc_page(GFP_KERNEL | __GFP_ZERO);
> + if (!page)
> + goto fail_free;
> + ns->offsets = page_address(page);
> + if (old_ns->offsets)
> + memcpy(ns->offsets, old_ns->offsets, sizeof(struct timens_offsets));
sizeof(*ns->offsets)
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 03/36] posix-clocks: Rename the clock_get() into clock_get_timespec()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format, rather than in (struct timespec).
Rename clock_get() callback into clock_get_timespec() as a preparation
for introducing clock_get_ktime().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 4 ++--
kernel/time/posix-clock.c | 8 ++++----
kernel/time/posix-cpu-timers.c | 32 ++++++++++++++++----------------
kernel/time/posix-timers.c | 22 +++++++++++-----------
kernel/time/posix-timers.h | 4 ++--
5 files changed, 35 insertions(+), 35 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 6742dac536f2..b5f3779eae57 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -644,7 +644,7 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp
}
/**
- * alarm_clock_get - posix clock_get interface
+ * alarm_clock_get - posix clock_get_timespec interface
* @which_clock: clockid
* @tp: timespec to fill.
*
@@ -824,7 +824,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
- .clock_get = alarm_clock_get,
+ .clock_get_timespec = alarm_clock_get,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
.timer_del = common_timer_del,
diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c
index ec960bb939fd..c8f9c9b1cd82 100644
--- a/kernel/time/posix-clock.c
+++ b/kernel/time/posix-clock.c
@@ -315,8 +315,8 @@ static int pc_clock_settime(clockid_t id, const struct timespec64 *ts)
}
const struct k_clock clock_posix_dynamic = {
- .clock_getres = pc_clock_getres,
- .clock_set = pc_clock_settime,
- .clock_get = pc_clock_gettime,
- .clock_adj = pc_clock_adjtime,
+ .clock_getres = pc_clock_getres,
+ .clock_set = pc_clock_settime,
+ .clock_get_timespec = pc_clock_gettime,
+ .clock_adj = pc_clock_adjtime,
};
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 0a426f4e3125..dccf7dfcd36a 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1417,26 +1417,26 @@ static int thread_cpu_timer_create(struct k_itimer *timer)
}
const struct k_clock clock_posix_cpu = {
- .clock_getres = posix_cpu_clock_getres,
- .clock_set = posix_cpu_clock_set,
- .clock_get = posix_cpu_clock_get,
- .timer_create = posix_cpu_timer_create,
- .nsleep = posix_cpu_nsleep,
- .timer_set = posix_cpu_timer_set,
- .timer_del = posix_cpu_timer_del,
- .timer_get = posix_cpu_timer_get,
- .timer_rearm = posix_cpu_timer_rearm,
+ .clock_getres = posix_cpu_clock_getres,
+ .clock_set = posix_cpu_clock_set,
+ .clock_get_timespec = posix_cpu_clock_get,
+ .timer_create = posix_cpu_timer_create,
+ .nsleep = posix_cpu_nsleep,
+ .timer_set = posix_cpu_timer_set,
+ .timer_del = posix_cpu_timer_del,
+ .timer_get = posix_cpu_timer_get,
+ .timer_rearm = posix_cpu_timer_rearm,
};
const struct k_clock clock_process = {
- .clock_getres = process_cpu_clock_getres,
- .clock_get = process_cpu_clock_get,
- .timer_create = process_cpu_timer_create,
- .nsleep = process_cpu_nsleep,
+ .clock_getres = process_cpu_clock_getres,
+ .clock_get_timespec = process_cpu_clock_get,
+ .timer_create = process_cpu_timer_create,
+ .nsleep = process_cpu_nsleep,
};
const struct k_clock clock_thread = {
- .clock_getres = thread_cpu_clock_getres,
- .clock_get = thread_cpu_clock_get,
- .timer_create = thread_cpu_timer_create,
+ .clock_getres = thread_cpu_clock_getres,
+ .clock_get_timespec = thread_cpu_clock_get,
+ .timer_create = thread_cpu_timer_create,
};
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index a71c1aab071c..36a4f6a7c4d6 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -667,7 +667,7 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
- kc->clock_get(timr->it_clock, &ts64);
+ kc->clock_get_timespec(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
/*
@@ -781,7 +781,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
* Posix magic: Relative CLOCK_REALTIME timers are not affected by
* clock modifications, so they become CLOCK_MONOTONIC based under the
* hood. See hrtimer_init(). Update timr->kclock, so the generic
- * functions which use timr->kclock->clock_get() work.
+ * functions which use timr->kclock->clock_get_timespec() work.
*
* Note: it_clock stays unmodified, because the next timer_set() might
* use ABSTIME, so it needs to switch back.
@@ -1073,7 +1073,7 @@ SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
if (!kc)
return -EINVAL;
- error = kc->clock_get(which_clock, &kernel_tp);
+ error = kc->clock_get_timespec(which_clock, &kernel_tp);
if (!error && put_timespec64(&kernel_tp, tp))
error = -EFAULT;
@@ -1155,7 +1155,7 @@ SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
if (!kc)
return -EINVAL;
- err = kc->clock_get(which_clock, &ts);
+ err = kc->clock_get_timespec(which_clock, &ts);
if (!err && put_old_timespec32(&ts, tp))
err = -EFAULT;
@@ -1267,7 +1267,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
static const struct k_clock clock_realtime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_clock_realtime_get,
+ .clock_get_timespec = posix_clock_realtime_get,
.clock_set = posix_clock_realtime_set,
.clock_adj = posix_clock_realtime_adj,
.nsleep = common_nsleep,
@@ -1284,7 +1284,7 @@ static const struct k_clock clock_realtime = {
static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_ktime_get_ts,
+ .clock_get_timespec = posix_ktime_get_ts,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1299,22 +1299,22 @@ static const struct k_clock clock_monotonic = {
static const struct k_clock clock_monotonic_raw = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_get_monotonic_raw,
+ .clock_get_timespec = posix_get_monotonic_raw,
};
static const struct k_clock clock_realtime_coarse = {
.clock_getres = posix_get_coarse_res,
- .clock_get = posix_get_realtime_coarse,
+ .clock_get_timespec = posix_get_realtime_coarse,
};
static const struct k_clock clock_monotonic_coarse = {
.clock_getres = posix_get_coarse_res,
- .clock_get = posix_get_monotonic_coarse,
+ .clock_get_timespec = posix_get_monotonic_coarse,
};
static const struct k_clock clock_tai = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_get_tai,
+ .clock_get_timespec = posix_get_tai,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1329,7 +1329,7 @@ static const struct k_clock clock_tai = {
static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_get_boottime,
+ .clock_get_timespec = posix_get_boottime,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h
index de5daa6d975a..b3cc9ee36a6b 100644
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -6,8 +6,8 @@ struct k_clock {
struct timespec64 *tp);
int (*clock_set)(const clockid_t which_clock,
const struct timespec64 *tp);
- int (*clock_get)(const clockid_t which_clock,
- struct timespec64 *tp);
+ int (*clock_get_timespec)(const clockid_t which_clock,
+ struct timespec64 *tp);
int (*clock_adj)(const clockid_t which_clock, struct __kernel_timex *tx);
int (*timer_create)(struct k_itimer *timer);
int (*nsleep)(const clockid_t which_clock, int flags,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 03/36] posix-clocks: Rename the clock_get() into clock_get_timespec()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format, rather than in (struct timespec).
Rename clock_get() callback into clock_get_timespec() as a preparation
for introducing clock_get_ktime().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 4 ++--
kernel/time/posix-clock.c | 8 ++++----
kernel/time/posix-cpu-timers.c | 32 ++++++++++++++++----------------
kernel/time/posix-timers.c | 22 +++++++++++-----------
kernel/time/posix-timers.h | 4 ++--
5 files changed, 35 insertions(+), 35 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 6742dac536f2..b5f3779eae57 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -644,7 +644,7 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp
}
/**
- * alarm_clock_get - posix clock_get interface
+ * alarm_clock_get - posix clock_get_timespec interface
* @which_clock: clockid
* @tp: timespec to fill.
*
@@ -824,7 +824,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
- .clock_get = alarm_clock_get,
+ .clock_get_timespec = alarm_clock_get,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
.timer_del = common_timer_del,
diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c
index ec960bb939fd..c8f9c9b1cd82 100644
--- a/kernel/time/posix-clock.c
+++ b/kernel/time/posix-clock.c
@@ -315,8 +315,8 @@ static int pc_clock_settime(clockid_t id, const struct timespec64 *ts)
}
const struct k_clock clock_posix_dynamic = {
- .clock_getres = pc_clock_getres,
- .clock_set = pc_clock_settime,
- .clock_get = pc_clock_gettime,
- .clock_adj = pc_clock_adjtime,
+ .clock_getres = pc_clock_getres,
+ .clock_set = pc_clock_settime,
+ .clock_get_timespec = pc_clock_gettime,
+ .clock_adj = pc_clock_adjtime,
};
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 0a426f4e3125..dccf7dfcd36a 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1417,26 +1417,26 @@ static int thread_cpu_timer_create(struct k_itimer *timer)
}
const struct k_clock clock_posix_cpu = {
- .clock_getres = posix_cpu_clock_getres,
- .clock_set = posix_cpu_clock_set,
- .clock_get = posix_cpu_clock_get,
- .timer_create = posix_cpu_timer_create,
- .nsleep = posix_cpu_nsleep,
- .timer_set = posix_cpu_timer_set,
- .timer_del = posix_cpu_timer_del,
- .timer_get = posix_cpu_timer_get,
- .timer_rearm = posix_cpu_timer_rearm,
+ .clock_getres = posix_cpu_clock_getres,
+ .clock_set = posix_cpu_clock_set,
+ .clock_get_timespec = posix_cpu_clock_get,
+ .timer_create = posix_cpu_timer_create,
+ .nsleep = posix_cpu_nsleep,
+ .timer_set = posix_cpu_timer_set,
+ .timer_del = posix_cpu_timer_del,
+ .timer_get = posix_cpu_timer_get,
+ .timer_rearm = posix_cpu_timer_rearm,
};
const struct k_clock clock_process = {
- .clock_getres = process_cpu_clock_getres,
- .clock_get = process_cpu_clock_get,
- .timer_create = process_cpu_timer_create,
- .nsleep = process_cpu_nsleep,
+ .clock_getres = process_cpu_clock_getres,
+ .clock_get_timespec = process_cpu_clock_get,
+ .timer_create = process_cpu_timer_create,
+ .nsleep = process_cpu_nsleep,
};
const struct k_clock clock_thread = {
- .clock_getres = thread_cpu_clock_getres,
- .clock_get = thread_cpu_clock_get,
- .timer_create = thread_cpu_timer_create,
+ .clock_getres = thread_cpu_clock_getres,
+ .clock_get_timespec = thread_cpu_clock_get,
+ .timer_create = thread_cpu_timer_create,
};
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index a71c1aab071c..36a4f6a7c4d6 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -667,7 +667,7 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
- kc->clock_get(timr->it_clock, &ts64);
+ kc->clock_get_timespec(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
/*
@@ -781,7 +781,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
* Posix magic: Relative CLOCK_REALTIME timers are not affected by
* clock modifications, so they become CLOCK_MONOTONIC based under the
* hood. See hrtimer_init(). Update timr->kclock, so the generic
- * functions which use timr->kclock->clock_get() work.
+ * functions which use timr->kclock->clock_get_timespec() work.
*
* Note: it_clock stays unmodified, because the next timer_set() might
* use ABSTIME, so it needs to switch back.
@@ -1073,7 +1073,7 @@ SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
if (!kc)
return -EINVAL;
- error = kc->clock_get(which_clock, &kernel_tp);
+ error = kc->clock_get_timespec(which_clock, &kernel_tp);
if (!error && put_timespec64(&kernel_tp, tp))
error = -EFAULT;
@@ -1155,7 +1155,7 @@ SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
if (!kc)
return -EINVAL;
- err = kc->clock_get(which_clock, &ts);
+ err = kc->clock_get_timespec(which_clock, &ts);
if (!err && put_old_timespec32(&ts, tp))
err = -EFAULT;
@@ -1267,7 +1267,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
static const struct k_clock clock_realtime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_clock_realtime_get,
+ .clock_get_timespec = posix_clock_realtime_get,
.clock_set = posix_clock_realtime_set,
.clock_adj = posix_clock_realtime_adj,
.nsleep = common_nsleep,
@@ -1284,7 +1284,7 @@ static const struct k_clock clock_realtime = {
static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_ktime_get_ts,
+ .clock_get_timespec = posix_ktime_get_ts,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1299,22 +1299,22 @@ static const struct k_clock clock_monotonic = {
static const struct k_clock clock_monotonic_raw = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_get_monotonic_raw,
+ .clock_get_timespec = posix_get_monotonic_raw,
};
static const struct k_clock clock_realtime_coarse = {
.clock_getres = posix_get_coarse_res,
- .clock_get = posix_get_realtime_coarse,
+ .clock_get_timespec = posix_get_realtime_coarse,
};
static const struct k_clock clock_monotonic_coarse = {
.clock_getres = posix_get_coarse_res,
- .clock_get = posix_get_monotonic_coarse,
+ .clock_get_timespec = posix_get_monotonic_coarse,
};
static const struct k_clock clock_tai = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_get_tai,
+ .clock_get_timespec = posix_get_tai,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1329,7 +1329,7 @@ static const struct k_clock clock_tai = {
static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get = posix_get_boottime,
+ .clock_get_timespec = posix_get_boottime,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h
index de5daa6d975a..b3cc9ee36a6b 100644
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -6,8 +6,8 @@ struct k_clock {
struct timespec64 *tp);
int (*clock_set)(const clockid_t which_clock,
const struct timespec64 *tp);
- int (*clock_get)(const clockid_t which_clock,
- struct timespec64 *tp);
+ int (*clock_get_timespec)(const clockid_t which_clock,
+ struct timespec64 *tp);
int (*clock_adj)(const clockid_t which_clock, struct __kernel_timex *tx);
int (*timer_create)(struct k_itimer *timer);
int (*nsleep)(const clockid_t which_clock, int flags,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 03/36] posix-clocks: Rename the clock_get() into clock_get_timespec()
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 17:24 ` Thomas Gleixner
-1 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 17:24 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
Just a nit vs. the subject line:
posix-clocks: Rename the clock_get() callback to clock_get_timespec()
> From: Andrei Vagin <avagin@gmail.com>
>
> The upcoming support for time namespaces requires to have access to:
> - The time in a task's time namespace for sys_clock_gettime()
> - The time in the root name space for common_timer_get()
>
> That adds a valid reason to finally implement a separate callback which
> returns the time in ktime_t format, rather than in (struct timespec).
>
> Rename clock_get() callback into clock_get_timespec() as a preparation
s/clock_get()/the clock_get()/
s/into/to/
> for introducing clock_get_ktime().
Otherwise this looks fine.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 04/36] posix-clocks: Rename .clock_get_timespec() callbacks accordingly
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format in (struct k_clock).
As a preparation ground for introducing clock_get_ktime(), the original
callback clock_get() was renamed into clock_get_timespec().
Reflect the renaming into callbacks realizations.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 6 +++---
kernel/time/posix-timers.c | 16 ++++++++--------
2 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index b5f3779eae57..995dd5aa68f0 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -644,13 +644,13 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp
}
/**
- * alarm_clock_get - posix clock_get_timespec interface
+ * alarm_clock_get_timespec - posix clock_get_timespec interface
* @which_clock: clockid
* @tp: timespec to fill.
*
* Provides the underlying alarm base time.
*/
-static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp)
+static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp)
{
struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
@@ -824,7 +824,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
- .clock_get_timespec = alarm_clock_get,
+ .clock_get_timespec = alarm_clock_get_timespec,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
.timer_del = common_timer_del,
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 36a4f6a7c4d6..4e89e342cfcc 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -165,7 +165,7 @@ static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
}
/* Get clock_realtime */
-static int posix_clock_realtime_get(clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_real_ts64(tp);
return 0;
@@ -187,7 +187,7 @@ static int posix_clock_realtime_adj(const clockid_t which_clock,
/*
* Get monotonic time for posix timers
*/
-static int posix_ktime_get_ts(clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_ts64(tp);
return 0;
@@ -222,13 +222,13 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
return 0;
}
-static int posix_get_boottime(const clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_boottime_ts64(tp);
return 0;
}
-static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_tai_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_clocktai_ts64(tp);
return 0;
@@ -1267,7 +1267,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
static const struct k_clock clock_realtime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_clock_realtime_get,
+ .clock_get_timespec = posix_get_realtime_timespec,
.clock_set = posix_clock_realtime_set,
.clock_adj = posix_clock_realtime_adj,
.nsleep = common_nsleep,
@@ -1284,7 +1284,7 @@ static const struct k_clock clock_realtime = {
static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_ktime_get_ts,
+ .clock_get_timespec = posix_get_monotonic_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1314,7 +1314,7 @@ static const struct k_clock clock_monotonic_coarse = {
static const struct k_clock clock_tai = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_get_tai,
+ .clock_get_timespec = posix_get_tai_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1329,7 +1329,7 @@ static const struct k_clock clock_tai = {
static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_get_boottime,
+ .clock_get_timespec = posix_get_boottime_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 04/36] posix-clocks: Rename .clock_get_timespec() callbacks accordingly
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format in (struct k_clock).
As a preparation ground for introducing clock_get_ktime(), the original
callback clock_get() was renamed into clock_get_timespec().
Reflect the renaming into callbacks realizations.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 6 +++---
kernel/time/posix-timers.c | 16 ++++++++--------
2 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index b5f3779eae57..995dd5aa68f0 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -644,13 +644,13 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp
}
/**
- * alarm_clock_get - posix clock_get_timespec interface
+ * alarm_clock_get_timespec - posix clock_get_timespec interface
* @which_clock: clockid
* @tp: timespec to fill.
*
* Provides the underlying alarm base time.
*/
-static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp)
+static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp)
{
struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
@@ -824,7 +824,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
- .clock_get_timespec = alarm_clock_get,
+ .clock_get_timespec = alarm_clock_get_timespec,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
.timer_del = common_timer_del,
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 36a4f6a7c4d6..4e89e342cfcc 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -165,7 +165,7 @@ static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
}
/* Get clock_realtime */
-static int posix_clock_realtime_get(clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_real_ts64(tp);
return 0;
@@ -187,7 +187,7 @@ static int posix_clock_realtime_adj(const clockid_t which_clock,
/*
* Get monotonic time for posix timers
*/
-static int posix_ktime_get_ts(clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_ts64(tp);
return 0;
@@ -222,13 +222,13 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
return 0;
}
-static int posix_get_boottime(const clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_boottime_ts64(tp);
return 0;
}
-static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp)
+static int posix_get_tai_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_clocktai_ts64(tp);
return 0;
@@ -1267,7 +1267,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
static const struct k_clock clock_realtime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_clock_realtime_get,
+ .clock_get_timespec = posix_get_realtime_timespec,
.clock_set = posix_clock_realtime_set,
.clock_adj = posix_clock_realtime_adj,
.nsleep = common_nsleep,
@@ -1284,7 +1284,7 @@ static const struct k_clock clock_realtime = {
static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_ktime_get_ts,
+ .clock_get_timespec = posix_get_monotonic_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1314,7 +1314,7 @@ static const struct k_clock clock_monotonic_coarse = {
static const struct k_clock clock_tai = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_get_tai,
+ .clock_get_timespec = posix_get_tai_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1329,7 +1329,7 @@ static const struct k_clock clock_tai = {
static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
- .clock_get_timespec = posix_get_boottime,
+ .clock_get_timespec = posix_get_boottime_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 05/36] alarmtimer: Rename gettime() callback to get_ktime()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a tasks time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
struct alarm_base needs to follow the same name convention, so rename
.gettime() callback into get_ktime() as a preparation for introducing
get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 995dd5aa68f0..5af13c859d03 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -36,13 +36,13 @@
* struct alarm_base - Alarm timer bases
* @lock: Lock for syncrhonized access to the base
* @timerqueue: Timerqueue head managing the list of events
- * @gettime: Function to read the time correlating to the base
+ * @get_ktime: Function to read the time correlating to the base
* @base_clockid: clockid for the base
*/
static struct alarm_base {
spinlock_t lock;
struct timerqueue_head timerqueue;
- ktime_t (*gettime)(void);
+ ktime_t (*get_ktime)(void);
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];
@@ -207,7 +207,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
spin_unlock_irqrestore(&base->lock, flags);
if (alarm->function)
- restart = alarm->function(alarm, base->gettime());
+ restart = alarm->function(alarm, base->get_ktime());
spin_lock_irqsave(&base->lock, flags);
if (restart != ALARMTIMER_NORESTART) {
@@ -217,7 +217,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
}
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_fired(alarm, base->gettime());
+ trace_alarmtimer_fired(alarm, base->get_ktime());
return ret;
}
@@ -225,7 +225,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
ktime_t alarm_expires_remaining(const struct alarm *alarm)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- return ktime_sub(alarm->node.expires, base->gettime());
+ return ktime_sub(alarm->node.expires, base->get_ktime());
}
EXPORT_SYMBOL_GPL(alarm_expires_remaining);
@@ -270,7 +270,7 @@ static int alarmtimer_suspend(struct device *dev)
spin_unlock_irqrestore(&base->lock, flags);
if (!next)
continue;
- delta = ktime_sub(next->expires, base->gettime());
+ delta = ktime_sub(next->expires, base->get_ktime());
if (!min || (delta < min)) {
expires = next->expires;
min = delta;
@@ -364,7 +364,7 @@ void alarm_start(struct alarm *alarm, ktime_t start)
hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS);
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_start(alarm, base->gettime());
+ trace_alarmtimer_start(alarm, base->get_ktime());
}
EXPORT_SYMBOL_GPL(alarm_start);
@@ -377,7 +377,7 @@ void alarm_start_relative(struct alarm *alarm, ktime_t start)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- start = ktime_add_safe(start, base->gettime());
+ start = ktime_add_safe(start, base->get_ktime());
alarm_start(alarm, start);
}
EXPORT_SYMBOL_GPL(alarm_start_relative);
@@ -414,7 +414,7 @@ int alarm_try_to_cancel(struct alarm *alarm)
alarmtimer_dequeue(base, alarm);
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_cancel(alarm, base->gettime());
+ trace_alarmtimer_cancel(alarm, base->get_ktime());
return ret;
}
EXPORT_SYMBOL_GPL(alarm_try_to_cancel);
@@ -474,7 +474,7 @@ u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- return alarm_forward(alarm, base->gettime(), interval);
+ return alarm_forward(alarm, base->get_ktime(), interval);
}
EXPORT_SYMBOL_GPL(alarm_forward_now);
@@ -500,7 +500,7 @@ static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
return;
}
- delta = ktime_sub(absexp, base->gettime());
+ delta = ktime_sub(absexp, base->get_ktime());
spin_lock_irqsave(&freezer_delta_lock, flags);
if (!freezer_delta || (delta < freezer_delta)) {
@@ -619,7 +619,7 @@ static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires,
struct alarm_base *base = &alarm_bases[alarm->type];
if (!absolute)
- expires = ktime_add_safe(expires, base->gettime());
+ expires = ktime_add_safe(expires, base->get_ktime());
if (sigev_none)
alarm->node.expires = expires;
else
@@ -657,7 +657,7 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
if (!alarmtimer_get_rtcdev())
return -EINVAL;
- *tp = ktime_to_timespec64(base->gettime());
+ *tp = ktime_to_timespec64(base->get_ktime());
return 0;
}
@@ -734,7 +734,7 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
struct timespec64 rmt;
ktime_t rem;
- rem = ktime_sub(absexp, alarm_bases[type].gettime());
+ rem = ktime_sub(absexp, alarm_bases[type].get_ktime());
if (rem <= 0)
return 0;
@@ -803,7 +803,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
exp = timespec64_to_ktime(*tsreq);
/* Convert (if necessary) to absolute time */
if (flags != TIMER_ABSTIME) {
- ktime_t now = alarm_bases[type].gettime();
+ ktime_t now = alarm_bases[type].get_ktime();
exp = ktime_add_safe(now, exp);
}
@@ -868,9 +868,9 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
- alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
- alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
for (i = 0; i < ALARM_NUMTYPE; i++) {
timerqueue_init_head(&alarm_bases[i].timerqueue);
spin_lock_init(&alarm_bases[i].lock);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 05/36] alarmtimer: Rename gettime() callback to get_ktime()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a tasks time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
struct alarm_base needs to follow the same name convention, so rename
.gettime() callback into get_ktime() as a preparation for introducing
get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 995dd5aa68f0..5af13c859d03 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -36,13 +36,13 @@
* struct alarm_base - Alarm timer bases
* @lock: Lock for syncrhonized access to the base
* @timerqueue: Timerqueue head managing the list of events
- * @gettime: Function to read the time correlating to the base
+ * @get_ktime: Function to read the time correlating to the base
* @base_clockid: clockid for the base
*/
static struct alarm_base {
spinlock_t lock;
struct timerqueue_head timerqueue;
- ktime_t (*gettime)(void);
+ ktime_t (*get_ktime)(void);
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];
@@ -207,7 +207,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
spin_unlock_irqrestore(&base->lock, flags);
if (alarm->function)
- restart = alarm->function(alarm, base->gettime());
+ restart = alarm->function(alarm, base->get_ktime());
spin_lock_irqsave(&base->lock, flags);
if (restart != ALARMTIMER_NORESTART) {
@@ -217,7 +217,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
}
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_fired(alarm, base->gettime());
+ trace_alarmtimer_fired(alarm, base->get_ktime());
return ret;
}
@@ -225,7 +225,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
ktime_t alarm_expires_remaining(const struct alarm *alarm)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- return ktime_sub(alarm->node.expires, base->gettime());
+ return ktime_sub(alarm->node.expires, base->get_ktime());
}
EXPORT_SYMBOL_GPL(alarm_expires_remaining);
@@ -270,7 +270,7 @@ static int alarmtimer_suspend(struct device *dev)
spin_unlock_irqrestore(&base->lock, flags);
if (!next)
continue;
- delta = ktime_sub(next->expires, base->gettime());
+ delta = ktime_sub(next->expires, base->get_ktime());
if (!min || (delta < min)) {
expires = next->expires;
min = delta;
@@ -364,7 +364,7 @@ void alarm_start(struct alarm *alarm, ktime_t start)
hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS);
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_start(alarm, base->gettime());
+ trace_alarmtimer_start(alarm, base->get_ktime());
}
EXPORT_SYMBOL_GPL(alarm_start);
@@ -377,7 +377,7 @@ void alarm_start_relative(struct alarm *alarm, ktime_t start)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- start = ktime_add_safe(start, base->gettime());
+ start = ktime_add_safe(start, base->get_ktime());
alarm_start(alarm, start);
}
EXPORT_SYMBOL_GPL(alarm_start_relative);
@@ -414,7 +414,7 @@ int alarm_try_to_cancel(struct alarm *alarm)
alarmtimer_dequeue(base, alarm);
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_cancel(alarm, base->gettime());
+ trace_alarmtimer_cancel(alarm, base->get_ktime());
return ret;
}
EXPORT_SYMBOL_GPL(alarm_try_to_cancel);
@@ -474,7 +474,7 @@ u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- return alarm_forward(alarm, base->gettime(), interval);
+ return alarm_forward(alarm, base->get_ktime(), interval);
}
EXPORT_SYMBOL_GPL(alarm_forward_now);
@@ -500,7 +500,7 @@ static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
return;
}
- delta = ktime_sub(absexp, base->gettime());
+ delta = ktime_sub(absexp, base->get_ktime());
spin_lock_irqsave(&freezer_delta_lock, flags);
if (!freezer_delta || (delta < freezer_delta)) {
@@ -619,7 +619,7 @@ static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires,
struct alarm_base *base = &alarm_bases[alarm->type];
if (!absolute)
- expires = ktime_add_safe(expires, base->gettime());
+ expires = ktime_add_safe(expires, base->get_ktime());
if (sigev_none)
alarm->node.expires = expires;
else
@@ -657,7 +657,7 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
if (!alarmtimer_get_rtcdev())
return -EINVAL;
- *tp = ktime_to_timespec64(base->gettime());
+ *tp = ktime_to_timespec64(base->get_ktime());
return 0;
}
@@ -734,7 +734,7 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
struct timespec64 rmt;
ktime_t rem;
- rem = ktime_sub(absexp, alarm_bases[type].gettime());
+ rem = ktime_sub(absexp, alarm_bases[type].get_ktime());
if (rem <= 0)
return 0;
@@ -803,7 +803,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
exp = timespec64_to_ktime(*tsreq);
/* Convert (if necessary) to absolute time */
if (flags != TIMER_ABSTIME) {
- ktime_t now = alarm_bases[type].gettime();
+ ktime_t now = alarm_bases[type].get_ktime();
exp = ktime_add_safe(now, exp);
}
@@ -868,9 +868,9 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
- alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
- alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
for (i = 0; i < ALARM_NUMTYPE; i++) {
timerqueue_init_head(&alarm_bases[i].timerqueue);
spin_lock_init(&alarm_bases[i].lock);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 06/36] alarmtimer: Provide get_timespec() callback
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
Wire up alarm bases with get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/posix-timers.h | 3 +++
kernel/time/alarmtimer.c | 8 ++++++--
kernel/time/posix-timers.c | 4 ++--
3 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
index 604cec0e41ba..ec2b2d8b95f6 100644
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -128,4 +128,7 @@ void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new);
void posixtimer_rearm(struct kernel_siginfo *info);
+
+int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp);
+int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp);
#endif
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 5af13c859d03..7732f0aabf6a 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -37,12 +37,15 @@
* @lock: Lock for syncrhonized access to the base
* @timerqueue: Timerqueue head managing the list of events
* @get_ktime: Function to read the time correlating to the base
+ * @get_timespec: Function to read the namespace time correlating to the base
* @base_clockid: clockid for the base
*/
static struct alarm_base {
spinlock_t lock;
struct timerqueue_head timerqueue;
ktime_t (*get_ktime)(void);
+ int (*get_timespec)(const clockid_t which_clock,
+ struct timespec64 *tp);
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];
@@ -657,8 +660,7 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
if (!alarmtimer_get_rtcdev())
return -EINVAL;
- *tp = ktime_to_timespec64(base->get_ktime());
- return 0;
+ return base->get_timespec(base->base_clockid, tp);
}
/**
@@ -869,8 +871,10 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_timespec = posix_get_realtime_timespec,
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_timespec = posix_get_boottime_timespec;
for (i = 0; i < ALARM_NUMTYPE; i++) {
timerqueue_init_head(&alarm_bases[i].timerqueue);
spin_lock_init(&alarm_bases[i].lock);
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 4e89e342cfcc..43049c5f1a22 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -165,7 +165,7 @@ static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
}
/* Get clock_realtime */
-static int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
+int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_real_ts64(tp);
return 0;
@@ -222,7 +222,7 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
return 0;
}
-static int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
+int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_boottime_ts64(tp);
return 0;
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 06/36] alarmtimer: Provide get_timespec() callback
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
Wire up alarm bases with get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/posix-timers.h | 3 +++
kernel/time/alarmtimer.c | 8 ++++++--
kernel/time/posix-timers.c | 4 ++--
3 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
index 604cec0e41ba..ec2b2d8b95f6 100644
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -128,4 +128,7 @@ void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new);
void posixtimer_rearm(struct kernel_siginfo *info);
+
+int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp);
+int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp);
#endif
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 5af13c859d03..7732f0aabf6a 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -37,12 +37,15 @@
* @lock: Lock for syncrhonized access to the base
* @timerqueue: Timerqueue head managing the list of events
* @get_ktime: Function to read the time correlating to the base
+ * @get_timespec: Function to read the namespace time correlating to the base
* @base_clockid: clockid for the base
*/
static struct alarm_base {
spinlock_t lock;
struct timerqueue_head timerqueue;
ktime_t (*get_ktime)(void);
+ int (*get_timespec)(const clockid_t which_clock,
+ struct timespec64 *tp);
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];
@@ -657,8 +660,7 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
if (!alarmtimer_get_rtcdev())
return -EINVAL;
- *tp = ktime_to_timespec64(base->get_ktime());
- return 0;
+ return base->get_timespec(base->base_clockid, tp);
}
/**
@@ -869,8 +871,10 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_timespec = posix_get_realtime_timespec,
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_timespec = posix_get_boottime_timespec;
for (i = 0; i < ALARM_NUMTYPE; i++) {
timerqueue_init_head(&alarm_bases[i].timerqueue);
spin_lock_init(&alarm_bases[i].lock);
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 4e89e342cfcc..43049c5f1a22 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -165,7 +165,7 @@ static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
}
/* Get clock_realtime */
-static int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
+int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_real_ts64(tp);
return 0;
@@ -222,7 +222,7 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
return 0;
}
-static int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
+int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_boottime_ts64(tp);
return 0;
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 07/36] posix-clocks: Introduce clock_get_ktime() callback
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
The callsite in common_timer_get() has already a comment:
/*
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
kc->clock_get(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 19 ++++++++++++++++++-
kernel/time/posix-timers.c | 26 +++++++++++++++++++++++++-
kernel/time/posix-timers.h | 3 +++
3 files changed, 46 insertions(+), 2 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 7732f0aabf6a..c8f8cf3d7d08 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -651,7 +651,7 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp
* @which_clock: clockid
* @tp: timespec to fill.
*
- * Provides the underlying alarm base time.
+ * Provides the underlying alarm base time in a tasks time namespace.
*/
static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp)
{
@@ -663,6 +663,22 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
return base->get_timespec(base->base_clockid, tp);
}
+/**
+ * alarm_clock_get_ktime - posix clock_get_ktime interface
+ * @which_clock: clockid
+ *
+ * Provides the underlying alarm base time in the root namespace.
+ */
+static ktime_t alarm_clock_get_ktime(clockid_t which_clock)
+{
+ struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
+
+ if (!alarmtimer_get_rtcdev())
+ return -EINVAL;
+
+ return base->get_ktime();
+}
+
/**
* alarm_timer_create - posix timer_create interface
* @new_timer: k_itimer pointer to manage
@@ -826,6 +842,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
+ .clock_get_ktime = alarm_clock_get_ktime,
.clock_get_timespec = alarm_clock_get_timespec,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 43049c5f1a22..7cf1216050d1 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -171,6 +171,11 @@ int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
return 0;
}
+static ktime_t posix_get_realtime_ktime(clockid_t which_clock)
+{
+ return ktime_get_real();
+}
+
/* Set clock_realtime */
static int posix_clock_realtime_set(const clockid_t which_clock,
const struct timespec64 *tp)
@@ -193,6 +198,11 @@ static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64
return 0;
}
+static ktime_t posix_get_monotonic_ktime(clockid_t which_clock)
+{
+ return ktime_get();
+}
+
/*
* Get monotonic-raw time for posix timers
*/
@@ -228,12 +238,22 @@ int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *
return 0;
}
+static ktime_t posix_get_boottime_ktime(const clockid_t which_clock)
+{
+ return ktime_get_boottime();
+}
+
static int posix_get_tai_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_clocktai_ts64(tp);
return 0;
}
+static ktime_t posix_get_tai_ktime(clockid_t which_clock)
+{
+ return ktime_get_clocktai();
+}
+
static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp)
{
tp->tv_sec = 0;
@@ -781,7 +801,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
* Posix magic: Relative CLOCK_REALTIME timers are not affected by
* clock modifications, so they become CLOCK_MONOTONIC based under the
* hood. See hrtimer_init(). Update timr->kclock, so the generic
- * functions which use timr->kclock->clock_get_timespec() work.
+ * functions which use timr->kclock->clock_get_*() work.
*
* Note: it_clock stays unmodified, because the next timer_set() might
* use ABSTIME, so it needs to switch back.
@@ -1268,6 +1288,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
static const struct k_clock clock_realtime = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_timespec = posix_get_realtime_timespec,
+ .clock_get_ktime = posix_get_realtime_ktime,
.clock_set = posix_clock_realtime_set,
.clock_adj = posix_clock_realtime_adj,
.nsleep = common_nsleep,
@@ -1285,6 +1306,7 @@ static const struct k_clock clock_realtime = {
static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_timespec = posix_get_monotonic_timespec,
+ .clock_get_ktime = posix_get_monotonic_ktime,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1314,6 +1336,7 @@ static const struct k_clock clock_monotonic_coarse = {
static const struct k_clock clock_tai = {
.clock_getres = posix_get_hrtimer_res,
+ .clock_get_ktime = posix_get_tai_ktime,
.clock_get_timespec = posix_get_tai_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
@@ -1329,6 +1352,7 @@ static const struct k_clock clock_tai = {
static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
+ .clock_get_ktime = posix_get_boottime_ktime,
.clock_get_timespec = posix_get_boottime_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h
index b3cc9ee36a6b..183994f7e466 100644
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -6,8 +6,11 @@ struct k_clock {
struct timespec64 *tp);
int (*clock_set)(const clockid_t which_clock,
const struct timespec64 *tp);
+ /* Returns the clock value in the current time namespace. */
int (*clock_get_timespec)(const clockid_t which_clock,
struct timespec64 *tp);
+ /* Returns the clock value in the root time namespace. */
+ ktime_t (*clock_get_ktime)(const clockid_t which_clock);
int (*clock_adj)(const clockid_t which_clock, struct __kernel_timex *tx);
int (*timer_create)(struct k_itimer *timer);
int (*nsleep)(const clockid_t which_clock, int flags,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 07/36] posix-clocks: Introduce clock_get_ktime() callback
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
The callsite in common_timer_get() has already a comment:
/*
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
kc->clock_get(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 19 ++++++++++++++++++-
kernel/time/posix-timers.c | 26 +++++++++++++++++++++++++-
kernel/time/posix-timers.h | 3 +++
3 files changed, 46 insertions(+), 2 deletions(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 7732f0aabf6a..c8f8cf3d7d08 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -651,7 +651,7 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp
* @which_clock: clockid
* @tp: timespec to fill.
*
- * Provides the underlying alarm base time.
+ * Provides the underlying alarm base time in a tasks time namespace.
*/
static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp)
{
@@ -663,6 +663,22 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
return base->get_timespec(base->base_clockid, tp);
}
+/**
+ * alarm_clock_get_ktime - posix clock_get_ktime interface
+ * @which_clock: clockid
+ *
+ * Provides the underlying alarm base time in the root namespace.
+ */
+static ktime_t alarm_clock_get_ktime(clockid_t which_clock)
+{
+ struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
+
+ if (!alarmtimer_get_rtcdev())
+ return -EINVAL;
+
+ return base->get_ktime();
+}
+
/**
* alarm_timer_create - posix timer_create interface
* @new_timer: k_itimer pointer to manage
@@ -826,6 +842,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
+ .clock_get_ktime = alarm_clock_get_ktime,
.clock_get_timespec = alarm_clock_get_timespec,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 43049c5f1a22..7cf1216050d1 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -171,6 +171,11 @@ int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
return 0;
}
+static ktime_t posix_get_realtime_ktime(clockid_t which_clock)
+{
+ return ktime_get_real();
+}
+
/* Set clock_realtime */
static int posix_clock_realtime_set(const clockid_t which_clock,
const struct timespec64 *tp)
@@ -193,6 +198,11 @@ static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64
return 0;
}
+static ktime_t posix_get_monotonic_ktime(clockid_t which_clock)
+{
+ return ktime_get();
+}
+
/*
* Get monotonic-raw time for posix timers
*/
@@ -228,12 +238,22 @@ int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *
return 0;
}
+static ktime_t posix_get_boottime_ktime(const clockid_t which_clock)
+{
+ return ktime_get_boottime();
+}
+
static int posix_get_tai_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_clocktai_ts64(tp);
return 0;
}
+static ktime_t posix_get_tai_ktime(clockid_t which_clock)
+{
+ return ktime_get_clocktai();
+}
+
static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp)
{
tp->tv_sec = 0;
@@ -781,7 +801,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
* Posix magic: Relative CLOCK_REALTIME timers are not affected by
* clock modifications, so they become CLOCK_MONOTONIC based under the
* hood. See hrtimer_init(). Update timr->kclock, so the generic
- * functions which use timr->kclock->clock_get_timespec() work.
+ * functions which use timr->kclock->clock_get_*() work.
*
* Note: it_clock stays unmodified, because the next timer_set() might
* use ABSTIME, so it needs to switch back.
@@ -1268,6 +1288,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
static const struct k_clock clock_realtime = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_timespec = posix_get_realtime_timespec,
+ .clock_get_ktime = posix_get_realtime_ktime,
.clock_set = posix_clock_realtime_set,
.clock_adj = posix_clock_realtime_adj,
.nsleep = common_nsleep,
@@ -1285,6 +1306,7 @@ static const struct k_clock clock_realtime = {
static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_timespec = posix_get_monotonic_timespec,
+ .clock_get_ktime = posix_get_monotonic_ktime,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
@@ -1314,6 +1336,7 @@ static const struct k_clock clock_monotonic_coarse = {
static const struct k_clock clock_tai = {
.clock_getres = posix_get_hrtimer_res,
+ .clock_get_ktime = posix_get_tai_ktime,
.clock_get_timespec = posix_get_tai_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
@@ -1329,6 +1352,7 @@ static const struct k_clock clock_tai = {
static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
+ .clock_get_ktime = posix_get_boottime_ktime,
.clock_get_timespec = posix_get_boottime_timespec,
.nsleep = common_nsleep,
.timer_create = common_timer_create,
diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h
index b3cc9ee36a6b..183994f7e466 100644
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -6,8 +6,11 @@ struct k_clock {
struct timespec64 *tp);
int (*clock_set)(const clockid_t which_clock,
const struct timespec64 *tp);
+ /* Returns the clock value in the current time namespace. */
int (*clock_get_timespec)(const clockid_t which_clock,
struct timespec64 *tp);
+ /* Returns the clock value in the root time namespace. */
+ ktime_t (*clock_get_ktime)(const clockid_t which_clock);
int (*clock_adj)(const clockid_t which_clock, struct __kernel_timex *tx);
int (*timer_create)(struct k_itimer *timer);
int (*nsleep)(const clockid_t which_clock, int flags,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 08/36] posix-timers: Use clock_get_ktime() in common_timer_get()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
Now, when the clock_get_ktime() callback exists, the suboptimal
timespec64-based conversion can be removed from common_timer_get().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/posix-timers.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 7cf1216050d1..1d41c6a41d63 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -665,7 +665,6 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
{
const struct k_clock *kc = timr->kclock;
ktime_t now, remaining, iv;
- struct timespec64 ts64;
bool sig_none;
sig_none = timr->it_sigev_notify == SIGEV_NONE;
@@ -683,12 +682,7 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
return;
}
- /*
- * The timespec64 based conversion is suboptimal, but it's not
- * worth to implement yet another callback.
- */
- kc->clock_get_timespec(timr->it_clock, &ts64);
- now = timespec64_to_ktime(ts64);
+ now = kc->clock_get_ktime(timr->it_clock);
/*
* When a requeue is pending or this is a SIGEV_NONE timer move the
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 08/36] posix-timers: Use clock_get_ktime() in common_timer_get()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
Now, when the clock_get_ktime() callback exists, the suboptimal
timespec64-based conversion can be removed from common_timer_get().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/posix-timers.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 7cf1216050d1..1d41c6a41d63 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -665,7 +665,6 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
{
const struct k_clock *kc = timr->kclock;
ktime_t now, remaining, iv;
- struct timespec64 ts64;
bool sig_none;
sig_none = timr->it_sigev_notify == SIGEV_NONE;
@@ -683,12 +682,7 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
return;
}
- /*
- * The timespec64 based conversion is suboptimal, but it's not
- * worth to implement yet another callback.
- */
- kc->clock_get_timespec(timr->it_clock, &ts64);
- now = timespec64_to_ktime(ts64);
+ now = kc->clock_get_ktime(timr->it_clock);
/*
* When a requeue is pending or this is a SIGEV_NONE timer move the
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 09/36] posix-clocks: Wire up clock_gettime() with timens offsets
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, Andrei Vagin
From: Andrei Vagin <avagin@openvz.org>
Adjust monotonic and boottime clocks with per-timens offsets.
As the result a process inside time namespace will see timers and clocks
corrected to offsets that were set on creating namespace.
Note that applications usually go through vDSO to get time, which is not
yet adjusted. Further changes complete time namespace virtualisation
with vDSO support.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 1 +
kernel/time/posix-stubs.c | 3 +++
kernel/time/posix-timers.c | 5 +++++
3 files changed, 9 insertions(+)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index c8f8cf3d7d08..fbf18b26faed 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -26,6 +26,7 @@
#include <linux/freezer.h>
#include <linux/compat.h>
#include <linux/module.h>
+#include <linux/time_namespace.h>
#include "posix-timers.h"
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 67df65f887ac..edaf075d1ee4 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -14,6 +14,7 @@
#include <linux/ktime.h>
#include <linux/timekeeping.h>
#include <linux/posix-timers.h>
+#include <linux/time_namespace.h>
#include <linux/compat.h>
#ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
@@ -77,9 +78,11 @@ int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
break;
case CLOCK_MONOTONIC:
ktime_get_ts64(tp);
+ timens_add_monotonic(tp);
break;
case CLOCK_BOOTTIME:
ktime_get_boottime_ts64(tp);
+ timens_add_boottime(tp);
break;
default:
return -EINVAL;
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 1d41c6a41d63..365ac40d46b1 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -30,6 +30,7 @@
#include <linux/hashtable.h>
#include <linux/compat.h>
#include <linux/nospec.h>
+#include <linux/time_namespace.h>
#include "timekeeping.h"
#include "posix-timers.h"
@@ -195,6 +196,7 @@ static int posix_clock_realtime_adj(const clockid_t which_clock,
static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_ts64(tp);
+ timens_add_monotonic(tp);
return 0;
}
@@ -209,6 +211,7 @@ static ktime_t posix_get_monotonic_ktime(clockid_t which_clock)
static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_raw_ts64(tp);
+ timens_add_monotonic(tp);
return 0;
}
@@ -223,6 +226,7 @@ static int posix_get_monotonic_coarse(clockid_t which_clock,
struct timespec64 *tp)
{
ktime_get_coarse_ts64(tp);
+ timens_add_monotonic(tp);
return 0;
}
@@ -235,6 +239,7 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_boottime_ts64(tp);
+ timens_add_boottime(tp);
return 0;
}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 09/36] posix-clocks: Wire up clock_gettime() with timens offsets
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@openvz.org>
Adjust monotonic and boottime clocks with per-timens offsets.
As the result a process inside time namespace will see timers and clocks
corrected to offsets that were set on creating namespace.
Note that applications usually go through vDSO to get time, which is not
yet adjusted. Further changes complete time namespace virtualisation
with vDSO support.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 1 +
kernel/time/posix-stubs.c | 3 +++
kernel/time/posix-timers.c | 5 +++++
3 files changed, 9 insertions(+)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index c8f8cf3d7d08..fbf18b26faed 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -26,6 +26,7 @@
#include <linux/freezer.h>
#include <linux/compat.h>
#include <linux/module.h>
+#include <linux/time_namespace.h>
#include "posix-timers.h"
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 67df65f887ac..edaf075d1ee4 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -14,6 +14,7 @@
#include <linux/ktime.h>
#include <linux/timekeeping.h>
#include <linux/posix-timers.h>
+#include <linux/time_namespace.h>
#include <linux/compat.h>
#ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
@@ -77,9 +78,11 @@ int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
break;
case CLOCK_MONOTONIC:
ktime_get_ts64(tp);
+ timens_add_monotonic(tp);
break;
case CLOCK_BOOTTIME:
ktime_get_boottime_ts64(tp);
+ timens_add_boottime(tp);
break;
default:
return -EINVAL;
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 1d41c6a41d63..365ac40d46b1 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -30,6 +30,7 @@
#include <linux/hashtable.h>
#include <linux/compat.h>
#include <linux/nospec.h>
+#include <linux/time_namespace.h>
#include "timekeeping.h"
#include "posix-timers.h"
@@ -195,6 +196,7 @@ static int posix_clock_realtime_adj(const clockid_t which_clock,
static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_ts64(tp);
+ timens_add_monotonic(tp);
return 0;
}
@@ -209,6 +211,7 @@ static ktime_t posix_get_monotonic_ktime(clockid_t which_clock)
static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_raw_ts64(tp);
+ timens_add_monotonic(tp);
return 0;
}
@@ -223,6 +226,7 @@ static int posix_get_monotonic_coarse(clockid_t which_clock,
struct timespec64 *tp)
{
ktime_get_coarse_ts64(tp);
+ timens_add_monotonic(tp);
return 0;
}
@@ -235,6 +239,7 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *
int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_boottime_ts64(tp);
+ timens_add_boottime(tp);
return 0;
}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 10/36] kernel: Add do_timens_ktime_to_host() helper
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
The helper subtracts namespace's clock offset from the given time
and checks that the result is in [0, KTIME_MAX].
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/time_namespace.h | 17 ++++++++++++++
kernel/time_namespace.c | 43 ++++++++++++++++++++++++++++++++++
2 files changed, 60 insertions(+)
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 334c1a1c6607..9ba9664ff0ab 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -56,6 +56,18 @@ static inline void timens_add_boottime(struct timespec64 *ts)
*ts = timespec64_add(*ts, ns_offsets->boottime);
}
+ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
+ struct timens_offsets *offsets);
+static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
+{
+ struct timens_offsets *offsets = current->nsproxy->time_ns->offsets;
+
+ if (!offsets)
+ return tim;
+
+ return do_timens_ktime_to_host(clockid, tim, offsets);
+}
+
#else
static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
{
@@ -82,6 +94,11 @@ static inline int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *ts
static inline void timens_add_monotonic(struct timespec64 *ts) {}
static inline void timens_add_boottime(struct timespec64 *ts) {}
+
+static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
+{
+ return tim;
+}
#endif
#endif /* _LINUX_TIMENS_H */
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index 394a9e168e7c..ff2c5de7e815 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -16,6 +16,49 @@
#include <linux/err.h>
#include <linux/mm.h>
+ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
+ struct timens_offsets *ns_offsets)
+{
+ ktime_t offset;
+
+ switch (clockid) {
+ case CLOCK_MONOTONIC:
+ offset = timespec64_to_ktime(ns_offsets->monotonic);
+ break;
+ case CLOCK_BOOTTIME:
+ case CLOCK_BOOTTIME_ALARM:
+ offset = timespec64_to_ktime(ns_offsets->boottime);
+ break;
+ default:
+ return tim;
+ }
+
+ /*
+ * Check that @tim value is in [offset, KTIME_MAX + offset]
+ * and subtract offset.
+ */
+ if (tim < offset) {
+ /*
+ * User can specify @tim *absolute* value - if it's lesser than
+ * the time namespace's offset - it's already expired.
+ */
+ tim = 0;
+ } else if (KTIME_MAX - tim < -offset) {
+ /*
+ * User-supplied @tim may be close or even equal KTIME_MAX
+ * and time namespace offset can be negative.
+ * Let's check (tim - offset) for an overflow.
+ * Return KTIME_MAX in such case, as the time value is
+ * thousands *years* in future anyway.
+ */
+ tim = KTIME_MAX;
+ } else {
+ tim = ktime_sub(tim, offset);
+ }
+
+ return tim;
+}
+
static struct ucounts *inc_time_namespaces(struct user_namespace *ns)
{
return inc_ucount(ns, current_euid(), UCOUNT_TIME_NAMESPACES);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 10/36] kernel: Add do_timens_ktime_to_host() helper
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
The helper subtracts namespace's clock offset from the given time
and checks that the result is in [0, KTIME_MAX].
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/time_namespace.h | 17 ++++++++++++++
kernel/time_namespace.c | 43 ++++++++++++++++++++++++++++++++++
2 files changed, 60 insertions(+)
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 334c1a1c6607..9ba9664ff0ab 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -56,6 +56,18 @@ static inline void timens_add_boottime(struct timespec64 *ts)
*ts = timespec64_add(*ts, ns_offsets->boottime);
}
+ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
+ struct timens_offsets *offsets);
+static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
+{
+ struct timens_offsets *offsets = current->nsproxy->time_ns->offsets;
+
+ if (!offsets)
+ return tim;
+
+ return do_timens_ktime_to_host(clockid, tim, offsets);
+}
+
#else
static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
{
@@ -82,6 +94,11 @@ static inline int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *ts
static inline void timens_add_monotonic(struct timespec64 *ts) {}
static inline void timens_add_boottime(struct timespec64 *ts) {}
+
+static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
+{
+ return tim;
+}
#endif
#endif /* _LINUX_TIMENS_H */
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index 394a9e168e7c..ff2c5de7e815 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -16,6 +16,49 @@
#include <linux/err.h>
#include <linux/mm.h>
+ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
+ struct timens_offsets *ns_offsets)
+{
+ ktime_t offset;
+
+ switch (clockid) {
+ case CLOCK_MONOTONIC:
+ offset = timespec64_to_ktime(ns_offsets->monotonic);
+ break;
+ case CLOCK_BOOTTIME:
+ case CLOCK_BOOTTIME_ALARM:
+ offset = timespec64_to_ktime(ns_offsets->boottime);
+ break;
+ default:
+ return tim;
+ }
+
+ /*
+ * Check that @tim value is in [offset, KTIME_MAX + offset]
+ * and subtract offset.
+ */
+ if (tim < offset) {
+ /*
+ * User can specify @tim *absolute* value - if it's lesser than
+ * the time namespace's offset - it's already expired.
+ */
+ tim = 0;
+ } else if (KTIME_MAX - tim < -offset) {
+ /*
+ * User-supplied @tim may be close or even equal KTIME_MAX
+ * and time namespace offset can be negative.
+ * Let's check (tim - offset) for an overflow.
+ * Return KTIME_MAX in such case, as the time value is
+ * thousands *years* in future anyway.
+ */
+ tim = KTIME_MAX;
+ } else {
+ tim = ktime_sub(tim, offset);
+ }
+
+ return tim;
+}
+
static struct ucounts *inc_time_namespaces(struct user_namespace *ns)
{
return inc_ucount(ns, current_euid(), UCOUNT_TIME_NAMESPACES);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 10/36] kernel: Add do_timens_ktime_to_host() helper
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 17:38 ` Thomas Gleixner
-1 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 17:38 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> +ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
> + struct timens_offsets *ns_offsets)
> +{
> + ktime_t offset;
> +
> + switch (clockid) {
> + case CLOCK_MONOTONIC:
> + offset = timespec64_to_ktime(ns_offsets->monotonic);
> + break;
> + case CLOCK_BOOTTIME:
> + case CLOCK_BOOTTIME_ALARM:
> + offset = timespec64_to_ktime(ns_offsets->boottime);
> + break;
> + default:
> + return tim;
> + }
> +
> + /*
> + * Check that @tim value is in [offset, KTIME_MAX + offset]
> + * and subtract offset.
> + */
> + if (tim < offset) {
> + /*
> + * User can specify @tim *absolute* value - if it's lesser than
> + * the time namespace's offset - it's already expired.
> + */
> + tim = 0;
> + } else if (KTIME_MAX - tim < -offset) {
> + /*
> + * User-supplied @tim may be close or even equal KTIME_MAX
> + * and time namespace offset can be negative.
> + * Let's check (tim - offset) for an overflow.
> + * Return KTIME_MAX in such case, as the time value is
> + * thousands *years* in future anyway.
> + */
> + tim = KTIME_MAX;
> + } else {
> + tim = ktime_sub(tim, offset);
> + }
While the overflow check is correct, wouldn't it be more intuitive to do:
tim = ktime_sub(tim, offset);
if (unlikely(tim > KTIME_MAX))
tim = KTIME_MAX;
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 11/36] timerfd: Make timerfd_settime() time namespace aware
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
timerfd_settime() accepts an absolute value of the experation time if
TFD_TIMER_ABSTIME is specified. This value is in task's time namespace
and has to be converted to the host's time namespace.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
fs/timerfd.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/timerfd.c b/fs/timerfd.c
index 48305ba41e3c..f9da5752a79e 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -26,6 +26,7 @@
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <linux/rcupdate.h>
+#include <linux/time_namespace.h>
struct timerfd_ctx {
union {
@@ -196,6 +197,8 @@ static int timerfd_setup(struct timerfd_ctx *ctx, int flags,
}
if (texp != 0) {
+ if (flags & TFD_TIMER_ABSTIME)
+ texp = timens_ktime_to_host(clockid, texp);
if (isalarm(ctx)) {
if (flags & TFD_TIMER_ABSTIME)
alarm_start(&ctx->t.alarm, texp);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 11/36] timerfd: Make timerfd_settime() time namespace aware
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
timerfd_settime() accepts an absolute value of the experation time if
TFD_TIMER_ABSTIME is specified. This value is in task's time namespace
and has to be converted to the host's time namespace.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
fs/timerfd.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/timerfd.c b/fs/timerfd.c
index 48305ba41e3c..f9da5752a79e 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -26,6 +26,7 @@
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <linux/rcupdate.h>
+#include <linux/time_namespace.h>
struct timerfd_ctx {
union {
@@ -196,6 +197,8 @@ static int timerfd_setup(struct timerfd_ctx *ctx, int flags,
}
if (texp != 0) {
+ if (flags & TFD_TIMER_ABSTIME)
+ texp = timens_ktime_to_host(clockid, texp);
if (isalarm(ctx)) {
if (flags & TFD_TIMER_ABSTIME)
alarm_start(&ctx->t.alarm, texp);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 12/36] posix-timers: Make timer_settime() time namespace aware
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
Wire timer_settime() syscall into time namespace virtualization.
sys_timer_settime() calls the ktime->timer_set() callback. Right now,
common_timer_set() is the only implementation for the callback.
There user-supplied timer's value is converted from timespec64 to ktime
and then timens_ktime_to_host() can be used to convert namespace's time
to the host time.
Inside a time namespace kernel's time differ on a fixed offset from
a user-supplied, but only absolute values (TIMER_ABSTIME) must
be converted.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/posix-timers.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 365ac40d46b1..1f30e3ef0918 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -891,6 +891,8 @@ int common_timer_set(struct k_itimer *timr, int flags,
timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
expires = timespec64_to_ktime(new_setting->it_value);
+ if (flags & TIMER_ABSTIME)
+ expires = timens_ktime_to_host(timr->it_clock, expires);
sigev_none = timr->it_sigev_notify == SIGEV_NONE;
kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 12/36] posix-timers: Make timer_settime() time namespace aware
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
Wire timer_settime() syscall into time namespace virtualization.
sys_timer_settime() calls the ktime->timer_set() callback. Right now,
common_timer_set() is the only implementation for the callback.
There user-supplied timer's value is converted from timespec64 to ktime
and then timens_ktime_to_host() can be used to convert namespace's time
to the host time.
Inside a time namespace kernel's time differ on a fixed offset from
a user-supplied, but only absolute values (TIMER_ABSTIME) must
be converted.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/posix-timers.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 365ac40d46b1..1f30e3ef0918 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -891,6 +891,8 @@ int common_timer_set(struct k_itimer *timr, int flags,
timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
expires = timespec64_to_ktime(new_setting->it_value);
+ if (flags & TIMER_ABSTIME)
+ expires = timens_ktime_to_host(timr->it_clock, expires);
sigev_none = timr->it_sigev_notify == SIGEV_NONE;
kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 13/36] alarmtimer: Make nanosleep time namespace aware
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
clock_nanosleep() accepts absolute values of expiration time when
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace, and has to be converted to the host's time.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index fbf18b26faed..751ed7f3cab2 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -825,6 +825,8 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
ktime_t now = alarm_bases[type].get_ktime();
exp = ktime_add_safe(now, exp);
+ } else {
+ exp = timens_ktime_to_host(which_clock, exp);
}
ret = alarmtimer_do_nsleep(&alarm, exp, type);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 13/36] alarmtimer: Make nanosleep time namespace aware
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
clock_nanosleep() accepts absolute values of expiration time when
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace, and has to be converted to the host's time.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index fbf18b26faed..751ed7f3cab2 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -825,6 +825,8 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
ktime_t now = alarm_bases[type].get_ktime();
exp = ktime_add_safe(now, exp);
+ } else {
+ exp = timens_ktime_to_host(which_clock, exp);
}
ret = alarmtimer_do_nsleep(&alarm, exp, type);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 14/36] hrtimers: Prepare hrtimer_nanosleep() for time namespaces
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
clock_nanosleep() accepts absolute values of expiration time when
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace, and has to be converted to the host's time.
There is timens_ktime_to_host() helper for converting time, but
it accepts ktime argument.
As a preparation, make hrtimer_nanosleep() accept a clock value in ktime
instead of timespec64.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/hrtimer.h | 2 +-
kernel/time/hrtimer.c | 8 ++++----
kernel/time/posix-stubs.c | 4 ++--
3 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 5df4bcff96d5..ed49ef359f26 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -500,7 +500,7 @@ static inline u64 hrtimer_forward_now(struct hrtimer *timer,
/* Precise sleep: */
extern int nanosleep_copyout(struct restart_block *, struct timespec64 *);
-extern long hrtimer_nanosleep(const struct timespec64 *rqtp,
+extern long hrtimer_nanosleep(ktime_t rqtp,
const enum hrtimer_mode mode,
const clockid_t clockid);
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 499122752649..fc972ae0de02 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1886,7 +1886,7 @@ static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
return ret;
}
-long hrtimer_nanosleep(const struct timespec64 *rqtp,
+long hrtimer_nanosleep(ktime_t rqtp,
const enum hrtimer_mode mode, const clockid_t clockid)
{
struct restart_block *restart;
@@ -1899,7 +1899,7 @@ long hrtimer_nanosleep(const struct timespec64 *rqtp,
slack = 0;
hrtimer_init_sleeper_on_stack(&t, clockid, mode);
- hrtimer_set_expires_range_ns(&t.timer, timespec64_to_ktime(*rqtp), slack);
+ hrtimer_set_expires_range_ns(&t.timer, rqtp, slack);
ret = do_nanosleep(&t, mode);
if (ret != -ERESTART_RESTARTBLOCK)
goto out;
@@ -1934,7 +1934,7 @@ SYSCALL_DEFINE2(nanosleep, struct __kernel_timespec __user *, rqtp,
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ return hrtimer_nanosleep(timespec64_to_ktime(tu), HRTIMER_MODE_REL, CLOCK_MONOTONIC);
}
#endif
@@ -1954,7 +1954,7 @@ SYSCALL_DEFINE2(nanosleep_time32, struct old_timespec32 __user *, rqtp,
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ return hrtimer_nanosleep(timespec64_to_ktime(tu), HRTIMER_MODE_REL, CLOCK_MONOTONIC);
}
#endif
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index edaf075d1ee4..2ccefc9ce184 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -147,7 +147,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
+ return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
@@ -233,7 +233,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
+ return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 14/36] hrtimers: Prepare hrtimer_nanosleep() for time namespaces
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
clock_nanosleep() accepts absolute values of expiration time when
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace, and has to be converted to the host's time.
There is timens_ktime_to_host() helper for converting time, but
it accepts ktime argument.
As a preparation, make hrtimer_nanosleep() accept a clock value in ktime
instead of timespec64.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/hrtimer.h | 2 +-
kernel/time/hrtimer.c | 8 ++++----
kernel/time/posix-stubs.c | 4 ++--
3 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 5df4bcff96d5..ed49ef359f26 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -500,7 +500,7 @@ static inline u64 hrtimer_forward_now(struct hrtimer *timer,
/* Precise sleep: */
extern int nanosleep_copyout(struct restart_block *, struct timespec64 *);
-extern long hrtimer_nanosleep(const struct timespec64 *rqtp,
+extern long hrtimer_nanosleep(ktime_t rqtp,
const enum hrtimer_mode mode,
const clockid_t clockid);
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 499122752649..fc972ae0de02 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1886,7 +1886,7 @@ static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
return ret;
}
-long hrtimer_nanosleep(const struct timespec64 *rqtp,
+long hrtimer_nanosleep(ktime_t rqtp,
const enum hrtimer_mode mode, const clockid_t clockid)
{
struct restart_block *restart;
@@ -1899,7 +1899,7 @@ long hrtimer_nanosleep(const struct timespec64 *rqtp,
slack = 0;
hrtimer_init_sleeper_on_stack(&t, clockid, mode);
- hrtimer_set_expires_range_ns(&t.timer, timespec64_to_ktime(*rqtp), slack);
+ hrtimer_set_expires_range_ns(&t.timer, rqtp, slack);
ret = do_nanosleep(&t, mode);
if (ret != -ERESTART_RESTARTBLOCK)
goto out;
@@ -1934,7 +1934,7 @@ SYSCALL_DEFINE2(nanosleep, struct __kernel_timespec __user *, rqtp,
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ return hrtimer_nanosleep(timespec64_to_ktime(tu), HRTIMER_MODE_REL, CLOCK_MONOTONIC);
}
#endif
@@ -1954,7 +1954,7 @@ SYSCALL_DEFINE2(nanosleep_time32, struct old_timespec32 __user *, rqtp,
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ return hrtimer_nanosleep(timespec64_to_ktime(tu), HRTIMER_MODE_REL, CLOCK_MONOTONIC);
}
#endif
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index edaf075d1ee4..2ccefc9ce184 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -147,7 +147,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
+ return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
@@ -233,7 +233,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
+ return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 14/36] hrtimers: Prepare hrtimer_nanosleep() for time namespaces
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 17:44 ` Thomas Gleixner
-1 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 17:44 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> ---
> include/linux/hrtimer.h | 2 +-
> kernel/time/hrtimer.c | 8 ++++----
> kernel/time/posix-stubs.c | 4 ++--
You forgot to convert the caller in posix-timers.c which breaks
bisectability. Please make sure, that every patch compiles and boots.
tools/perf/examples/bpf/5sec.c breaks as well.
Thnaks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 15/36] posix-timers: Make clock_nanosleep() time namespace aware
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
clock_nanosleep() accepts absolute values of expiration time, if the
TIMER_ABSTIME flag is set. This value is in the task time namespace,
which has to be converted to the host time namespace.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/posix-stubs.c | 12 ++++++++++--
kernel/time/posix-timers.c | 21 ++++++++++++++++++---
2 files changed, 28 insertions(+), 5 deletions(-)
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 2ccefc9ce184..47ee2684d250 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -129,6 +129,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
struct __kernel_timespec __user *, rmtp)
{
struct timespec64 t;
+ ktime_t texp;
switch (which_clock) {
case CLOCK_REALTIME:
@@ -147,7 +148,10 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
+ texp = timespec64_to_ktime(t);
+ if (flags & TIMER_ABSTIME)
+ texp = timens_ktime_to_host(clockid, texp);
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
@@ -215,6 +219,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
struct old_timespec32 __user *, rmtp)
{
struct timespec64 t;
+ ktime texp;
switch (which_clock) {
case CLOCK_REALTIME:
@@ -233,7 +238,10 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
+ texp = timespec64_to_ktime(t);
+ if (flags & TIMER_ABSTIME)
+ texp = timens_ktime_to_host(clockid, texp);
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 1f30e3ef0918..c71eedd17c94 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -1227,7 +1227,22 @@ SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
static int common_nsleep(const clockid_t which_clock, int flags,
const struct timespec64 *rqtp)
{
- return hrtimer_nanosleep(rqtp, flags & TIMER_ABSTIME ?
+ ktime_t texp = timespec64_to_ktime(*rqtp);
+
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
+ HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
+ which_clock);
+}
+
+static int common_nsleep_timens(const clockid_t which_clock, int flags,
+ const struct timespec64 *rqtp)
+{
+ ktime_t texp = timespec64_to_ktime(*rqtp);
+
+ if (flags & TIMER_ABSTIME)
+ texp = timens_ktime_to_host(which_clock, texp);
+
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
@@ -1308,7 +1323,7 @@ static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_timespec = posix_get_monotonic_timespec,
.clock_get_ktime = posix_get_monotonic_ktime,
- .nsleep = common_nsleep,
+ .nsleep = common_nsleep_timens,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
.timer_get = common_timer_get,
@@ -1355,7 +1370,7 @@ static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_ktime = posix_get_boottime_ktime,
.clock_get_timespec = posix_get_boottime_timespec,
- .nsleep = common_nsleep,
+ .nsleep = common_nsleep_timens,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
.timer_get = common_timer_get,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 15/36] posix-timers: Make clock_nanosleep() time namespace aware
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
clock_nanosleep() accepts absolute values of expiration time, if the
TIMER_ABSTIME flag is set. This value is in the task time namespace,
which has to be converted to the host time namespace.
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/posix-stubs.c | 12 ++++++++++--
kernel/time/posix-timers.c | 21 ++++++++++++++++++---
2 files changed, 28 insertions(+), 5 deletions(-)
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 2ccefc9ce184..47ee2684d250 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -129,6 +129,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
struct __kernel_timespec __user *, rmtp)
{
struct timespec64 t;
+ ktime_t texp;
switch (which_clock) {
case CLOCK_REALTIME:
@@ -147,7 +148,10 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
+ texp = timespec64_to_ktime(t);
+ if (flags & TIMER_ABSTIME)
+ texp = timens_ktime_to_host(clockid, texp);
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
@@ -215,6 +219,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
struct old_timespec32 __user *, rmtp)
{
struct timespec64 t;
+ ktime texp;
switch (which_clock) {
case CLOCK_REALTIME:
@@ -233,7 +238,10 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
+ texp = timespec64_to_ktime(t);
+ if (flags & TIMER_ABSTIME)
+ texp = timens_ktime_to_host(clockid, texp);
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 1f30e3ef0918..c71eedd17c94 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -1227,7 +1227,22 @@ SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
static int common_nsleep(const clockid_t which_clock, int flags,
const struct timespec64 *rqtp)
{
- return hrtimer_nanosleep(rqtp, flags & TIMER_ABSTIME ?
+ ktime_t texp = timespec64_to_ktime(*rqtp);
+
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
+ HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
+ which_clock);
+}
+
+static int common_nsleep_timens(const clockid_t which_clock, int flags,
+ const struct timespec64 *rqtp)
+{
+ ktime_t texp = timespec64_to_ktime(*rqtp);
+
+ if (flags & TIMER_ABSTIME)
+ texp = timens_ktime_to_host(which_clock, texp);
+
+ return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
@@ -1308,7 +1323,7 @@ static const struct k_clock clock_monotonic = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_timespec = posix_get_monotonic_timespec,
.clock_get_ktime = posix_get_monotonic_ktime,
- .nsleep = common_nsleep,
+ .nsleep = common_nsleep_timens,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
.timer_get = common_timer_get,
@@ -1355,7 +1370,7 @@ static const struct k_clock clock_boottime = {
.clock_getres = posix_get_hrtimer_res,
.clock_get_ktime = posix_get_boottime_ktime,
.clock_get_timespec = posix_get_boottime_timespec,
- .nsleep = common_nsleep,
+ .nsleep = common_nsleep_timens,
.timer_create = common_timer_create,
.timer_set = common_timer_set,
.timer_get = common_timer_get,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 16/36] fd/proc: Respect boottime inside time namespace for /proc/uptime
2019-08-15 16:38 ` Dmitry Safonov
` (15 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
2019-08-16 0:46 ` Randy Dunlap
-1 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
fs/proc/uptime.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/proc/uptime.c b/fs/proc/uptime.c
index a4c2791ab70b..5a1b228964fb 100644
--- a/fs/proc/uptime.c
+++ b/fs/proc/uptime.c
@@ -5,6 +5,7 @@
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/time.h>
+#include <linux/time_namespace.h>
#include <linux/kernel_stat.h>
static int uptime_proc_show(struct seq_file *m, void *v)
@@ -20,6 +21,8 @@ static int uptime_proc_show(struct seq_file *m, void *v)
nsec += (__force u64) kcpustat_cpu(i).cpustat[CPUTIME_IDLE];
ktime_get_boottime_ts64(&uptime);
+ timens_add_boottime(&uptime);
+
idle.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem);
idle.tv_nsec = rem;
seq_printf(m, "%lu.%02lu %lu.%02lu\n",
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 16/36] fd/proc: Respect boottime inside time namespace for /proc/uptime
2019-08-15 16:38 ` [PATCHv6 16/36] fd/proc: Respect boottime inside time namespace for /proc/uptime Dmitry Safonov
@ 2019-08-16 0:46 ` Randy Dunlap
0 siblings, 0 replies; 87+ messages in thread
From: Randy Dunlap @ 2019-08-16 0:46 UTC (permalink / raw)
To: Dmitry Safonov, linux-kernel
Cc: Dmitry Safonov, Adrian Reber, Andrei Vagin, Andy Lutomirski,
Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
On 8/15/19 9:38 AM, Dmitry Safonov wrote:
> Co-developed-by: Andrei Vagin <avagin@openvz.org>
> Signed-off-by: Andrei Vagin <avagin@openvz.org>
> Signed-off-by: Dmitry Safonov <dima@arista.com>
> ---
> fs/proc/uptime.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/fs/proc/uptime.c b/fs/proc/uptime.c
> index a4c2791ab70b..5a1b228964fb 100644
> --- a/fs/proc/uptime.c
> +++ b/fs/proc/uptime.c
Please fix $Subject (s/fd/fs/)
thanks.
--
~Randy
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 17/36] x86/vdso2c: Correct err messages on file opening
2019-08-15 16:38 ` Dmitry Safonov
` (16 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
err() message in main() is misleading: it should print `outfilename`,
which is argv[3], not argv[2].
Correct error messages to be more precise about what failed and for
which file.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vdso2c.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/entry/vdso/vdso2c.c b/arch/x86/entry/vdso/vdso2c.c
index 3a4d8d4d39f8..ce67370d14e5 100644
--- a/arch/x86/entry/vdso/vdso2c.c
+++ b/arch/x86/entry/vdso/vdso2c.c
@@ -184,7 +184,7 @@ static void map_input(const char *name, void **addr, size_t *len, int prot)
int fd = open(name, O_RDONLY);
if (fd == -1)
- err(1, "%s", name);
+ err(1, "open(%s)", name);
tmp_len = lseek(fd, 0, SEEK_END);
if (tmp_len == (off_t)-1)
@@ -237,7 +237,7 @@ int main(int argc, char **argv)
outfilename = argv[3];
outfile = fopen(outfilename, "w");
if (!outfile)
- err(1, "%s", argv[2]);
+ err(1, "fopen(%s)", outfilename);
go(raw_addr, raw_len, stripped_addr, stripped_len, outfile, name);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 18/36] x86/vdso2c: Convert iterator to unsigned
2019-08-15 16:38 ` Dmitry Safonov
` (17 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
i and j are used everywhere with unsigned types.
Cleanup and prettify the code a bit.
Introduce syms_nr for readability and as a preparation for allocating an
array of vDSO entries that will be needed for creating two vdso .so's:
one for host tasks and another for processes inside time namespace.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vdso2c.h | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index a20b134de2a8..80be339ee93e 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -13,7 +13,7 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
unsigned long load_size = -1; /* Work around bogus warning */
unsigned long mapping_size;
ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
- int i;
+ unsigned int i, syms_nr;
unsigned long j;
ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
*alt_sec = NULL;
@@ -86,11 +86,10 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
strtab_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
GET_LE(&hdr->e_shentsize) * GET_LE(&symtab_hdr->sh_link);
+ syms_nr = GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize);
/* Walk the symbol table */
- for (i = 0;
- i < GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize);
- i++) {
- int k;
+ for (i = 0; i < syms_nr; i++) {
+ unsigned int k;
ELF(Sym) *sym = raw_addr + GET_LE(&symtab_hdr->sh_offset) +
GET_LE(&symtab_hdr->sh_entsize) * i;
const char *sym_name = raw_addr +
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 19/36] x86/vdso/Makefile: Add vobjs32
2019-08-15 16:38 ` Dmitry Safonov
` (18 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
Treat ia32/i386 objects in array the same As for 64-bit vdso objects.
This is a preparation ground to avoid code duplication on introduction
timens vdso.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/Makefile | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 8df549138193..d4bffc4cabd1 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -24,6 +24,8 @@ VDSO32-$(CONFIG_IA32_EMULATION) := y
# files to link into the vdso
vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
+vobjs32-y := vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o
+vobjs32-y += vdso32/vclock_gettime.o
# files to link into kernel
obj-y += vma.o
@@ -37,10 +39,12 @@ vdso_img-$(VDSO32-y) += 32
obj-$(VDSO32-y) += vdso32-setup.o
vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
+vobjs32 := $(foreach F,$(vobjs32-y),$(obj)/$F)
$(obj)/vdso.o: $(obj)/vdso.so
targets += vdso.lds $(vobjs-y)
+targets += vdso32/vdso32.lds $(vobjs32-y)
# Build the vDSO image C files and link them in.
vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o)
@@ -131,10 +135,6 @@ $(obj)/vdsox32.so.dbg: $(obj)/vdsox32.lds $(vobjx32s) FORCE
CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
VDSO_LDFLAGS_vdso32.lds = -m elf_i386 -soname linux-gate.so.1
-targets += vdso32/vdso32.lds
-targets += vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o
-targets += vdso32/vclock_gettime.o
-
KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) -DBUILD_VDSO
$(obj)/vdso32.so.dbg: KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
$(obj)/vdso32.so.dbg: asflags-$(CONFIG_X86_64) += -m32
@@ -159,12 +159,7 @@ endif
$(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
-$(obj)/vdso32.so.dbg: FORCE \
- $(obj)/vdso32/vdso32.lds \
- $(obj)/vdso32/vclock_gettime.o \
- $(obj)/vdso32/note.o \
- $(obj)/vdso32/system_call.o \
- $(obj)/vdso32/sigreturn.o
+$(obj)/vdso32.so.dbg: $(obj)/vdso32/vdso32.lds $(vobjs32) FORCE
$(call if_changed,vdso_and_check)
#
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 20/36] x86/vdso: Restrict splitting VVAR VMA
2019-08-15 16:38 ` Dmitry Safonov
` (19 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
Although, time namespace can work with VVAR VMA split, it seems worth
to forbid splitting VVAR resulting in stricter ABI and reducing amount
of corner-cases to consider while working further on VDSO.
I don't think there is any use-case for partial mremap() of vvar,
but if there is any - this patch can be easily reverted.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vma.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 349a61d8bf34..3f05418642a8 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -84,6 +84,18 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
return 0;
}
+static int vvar_mremap(const struct vm_special_mapping *sm,
+ struct vm_area_struct *new_vma)
+{
+ unsigned long new_size = new_vma->vm_end - new_vma->vm_start;
+ const struct vdso_image *image = new_vma->vm_mm->context.vdso_image;
+
+ if (new_size != -image->sym_vvar_start)
+ return -EINVAL;
+
+ return 0;
+}
+
static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
@@ -136,6 +148,7 @@ static const struct vm_special_mapping vdso_mapping = {
static const struct vm_special_mapping vvar_mapping = {
.name = "[vvar]",
.fault = vvar_fault,
+ .mremap = vvar_mremap,
};
/*
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 21/36] x86/vdso: Rename vdso_image {.data=>.text}
2019-08-15 16:38 ` Dmitry Safonov
` (20 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
To avoid any confusion with VVAR.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vdso2c.h | 2 +-
arch/x86/entry/vdso/vma.c | 6 +++---
arch/x86/include/asm/vdso.h | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index 80be339ee93e..7556bb70ed8b 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -158,7 +158,7 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
fprintf(outfile, "\n};\n\n");
fprintf(outfile, "const struct vdso_image %s = {\n", image_name);
- fprintf(outfile, "\t.data = raw_data,\n");
+ fprintf(outfile, "\t.text = raw_data,\n");
fprintf(outfile, "\t.size = %lu,\n", mapping_size);
if (alt_sec) {
fprintf(outfile, "\t.alt = %lu,\n",
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 3f05418642a8..2dc4f0b5481c 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -32,8 +32,8 @@ void __init init_vdso_image(const struct vdso_image *image)
{
BUG_ON(image->size % PAGE_SIZE != 0);
- apply_alternatives((struct alt_instr *)(image->data + image->alt),
- (struct alt_instr *)(image->data + image->alt +
+ apply_alternatives((struct alt_instr *)(image->text + image->alt),
+ (struct alt_instr *)(image->text + image->alt +
image->alt_len));
}
@@ -47,7 +47,7 @@ static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
if (!image || (vmf->pgoff << PAGE_SHIFT) >= image->size)
return VM_FAULT_SIGBUS;
- vmf->page = virt_to_page(image->data + (vmf->pgoff << PAGE_SHIFT));
+ vmf->page = virt_to_page(image->text + (vmf->pgoff << PAGE_SHIFT));
get_page(vmf->page);
return 0;
}
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index 230474e2ddb5..dffdc12cc7d6 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -11,7 +11,7 @@
#include <linux/mm_types.h>
struct vdso_image {
- void *data;
+ void *text;
unsigned long size; /* Always a multiple of PAGE_SIZE */
unsigned long alt, alt_len;
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 22/36] x86/vdso: Add offsets page in vvar
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, Andrei Vagin
From: Andrei Vagin <avagin@openvz.org>
As modern applications fetch time from VDSO without entering the kernel,
it's needed to provide offsets for userspace code inside time namespace.
A page for timens offsets is allocated on time namespace construction.
Put that page into VVAR for tasks inside timens and zero page for
host processes.
As VDSO code is already optimized as much as possible in terms of speed,
any new if-condition in VDSO code is undesirable; the goal is to provide
two .so(s), as was originally suggested by Andy and Thomas:
- for host tasks with optimized-out clk_to_ns() without any penalty
- for processes inside timens with clk_to_ns()
For this purpose, define clk_to_ns() under CONFIG_TIME_NS.
To eliminate any performance regression, clk_to_ns() will be called
under static_branch with follow-up patches, that adds support for
patching vdso.
VDSO mappings are platform-specific, add Kconfig dependency for arch.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/Kconfig | 5 +++
arch/x86/Kconfig | 1 +
arch/x86/entry/vdso/vdso-layout.lds.S | 9 ++++-
arch/x86/entry/vdso/vdso2c.c | 3 ++
arch/x86/entry/vdso/vma.c | 12 +++++++
arch/x86/include/asm/vdso.h | 1 +
init/Kconfig | 1 +
lib/vdso/gettimeofday.c | 47 +++++++++++++++++++++++++++
8 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 719b27275f86..5ddb92e6bfe0 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -740,6 +740,11 @@ config HAVE_ARCH_NVRAM_OPS
config ISA_BUS_API
def_bool ISA
+config ARCH_HAS_VDSO_TIME_NS
+ bool
+ help
+ VDSO can add time-ns offsets without entering kernel.
+
#
# ABI hall of shame
#
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d685677d90f0..7ab810bc965d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -81,6 +81,7 @@ config X86
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VDSO_TIME_NS
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index 93c6dc7812d0..ba216527e59f 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -7,6 +7,12 @@
* This script controls its layout.
*/
+#ifdef CONFIG_TIME_NS
+# define TIMENS_SZ PAGE_SIZE
+#else
+# define TIMENS_SZ 0
+#endif
+
SECTIONS
{
/*
@@ -16,7 +22,7 @@ SECTIONS
* segment.
*/
- vvar_start = . - 3 * PAGE_SIZE;
+ vvar_start = . - (3 * PAGE_SIZE + TIMENS_SZ);
vvar_page = vvar_start;
/* Place all vvars at the offsets in asm/vvar.h. */
@@ -28,6 +34,7 @@ SECTIONS
pvclock_page = vvar_start + PAGE_SIZE;
hvclock_page = vvar_start + 2 * PAGE_SIZE;
+ timens_page = vvar_start + 3 * PAGE_SIZE;
. = SIZEOF_HEADERS;
diff --git a/arch/x86/entry/vdso/vdso2c.c b/arch/x86/entry/vdso/vdso2c.c
index ce67370d14e5..7380908045c7 100644
--- a/arch/x86/entry/vdso/vdso2c.c
+++ b/arch/x86/entry/vdso/vdso2c.c
@@ -75,12 +75,14 @@ enum {
sym_vvar_page,
sym_pvclock_page,
sym_hvclock_page,
+ sym_timens_page,
};
const int special_pages[] = {
sym_vvar_page,
sym_pvclock_page,
sym_hvclock_page,
+ sym_timens_page,
};
struct vdso_sym {
@@ -93,6 +95,7 @@ struct vdso_sym required_syms[] = {
[sym_vvar_page] = {"vvar_page", true},
[sym_pvclock_page] = {"pvclock_page", true},
[sym_hvclock_page] = {"hvclock_page", true},
+ [sym_timens_page] = {"timens_page", true},
{"VDSO32_NOTE_MASK", true},
{"__kernel_vsyscall", true},
{"__kernel_sigreturn", true},
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 2dc4f0b5481c..9bd66f84db5e 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -14,6 +14,7 @@
#include <linux/elf.h>
#include <linux/cpu.h>
#include <linux/ptrace.h>
+#include <linux/time_namespace.h>
#include <asm/pvclock.h>
#include <asm/vgtod.h>
#include <asm/proto.h>
@@ -23,6 +24,7 @@
#include <asm/desc.h>
#include <asm/cpufeature.h>
#include <clocksource/hyperv_timer.h>
+#include <asm/page.h>
#if defined(CONFIG_X86_64)
unsigned int __read_mostly vdso64_enabled = 1;
@@ -135,6 +137,16 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
if (tsc_pg && vclock_was_used(VCLOCK_HVCLOCK))
return vmf_insert_pfn(vma, vmf->address,
vmalloc_to_pfn(tsc_pg));
+ } else if (sym_offset == image->sym_timens_page) {
+ struct time_namespace *ns = current->nsproxy->time_ns;
+ unsigned long pfn;
+
+ if (!ns->offsets)
+ pfn = page_to_pfn(ZERO_PAGE(0));
+ else
+ pfn = page_to_pfn(virt_to_page(ns->offsets));
+
+ return vmf_insert_pfn(vma, vmf->address, pfn);
}
return VM_FAULT_SIGBUS;
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index dffdc12cc7d6..9d420c545607 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -21,6 +21,7 @@ struct vdso_image {
long sym_vvar_page;
long sym_pvclock_page;
long sym_hvclock_page;
+ long sym_timens_page;
long sym_VDSO32_NOTE_MASK;
long sym___kernel_sigreturn;
long sym___kernel_rt_sigreturn;
diff --git a/init/Kconfig b/init/Kconfig
index 525dc3ed86c4..7adf939eeaa8 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1074,6 +1074,7 @@ config UTS_NS
config TIME_NS
bool "TIME namespace"
+ depends on ARCH_HAS_VDSO_TIME_NS
default y
help
In this namespace boottime and monotonic clocks can be set.
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index e630e7ff57f1..8589c66ff3e7 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -7,6 +7,7 @@
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/hrtimer_defs.h>
+#include <linux/timens_offsets.h>
#include <vdso/datapage.h>
#include <vdso/helpers.h>
@@ -38,6 +39,48 @@ u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
}
#endif
+#ifdef CONFIG_TIME_NS
+extern u8 timens_page
+ __attribute__((visibility("hidden")));
+
+notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts)
+{
+ struct timens_offsets *timens = (struct timens_offsets *) &timens_page;
+ struct timespec64 *offset64;
+
+ switch (clk) {
+ case CLOCK_MONOTONIC:
+ case CLOCK_MONOTONIC_COARSE:
+ case CLOCK_MONOTONIC_RAW:
+ offset64 = &timens->monotonic;
+ break;
+ case CLOCK_BOOTTIME:
+ offset64 = &timens->boottime;
+ break;
+ default:
+ return;
+ }
+
+ /*
+ * The kernel allows to set a negative offset only if the current clock
+ * value in a namespace is positive, so the result tv_sec can't be
+ * negative here.
+ */
+ ts->tv_nsec += offset64->tv_nsec;
+ ts->tv_sec += offset64->tv_sec;
+ if (ts->tv_nsec >= NSEC_PER_SEC) {
+ ts->tv_nsec -= NSEC_PER_SEC;
+ ts->tv_sec++;
+ }
+ if (ts->tv_nsec < 0) {
+ ts->tv_nsec += NSEC_PER_SEC;
+ ts->tv_sec--;
+ }
+}
+#else
+notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts) {}
+#endif
+
static int do_hres(const struct vdso_data *vd, clockid_t clk,
struct __kernel_timespec *ts)
{
@@ -65,6 +108,8 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk,
ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
ts->tv_nsec = ns;
+ clk_to_ns(clk, ts);
+
return 0;
}
@@ -79,6 +124,8 @@ static void do_coarse(const struct vdso_data *vd, clockid_t clk,
ts->tv_sec = vdso_ts->sec;
ts->tv_nsec = vdso_ts->nsec;
} while (unlikely(vdso_read_retry(vd, seq)));
+
+ clk_to_ns(clk, ts);
}
static __maybe_unused int
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 22/36] x86/vdso: Add offsets page in vvar
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@openvz.org>
As modern applications fetch time from VDSO without entering the kernel,
it's needed to provide offsets for userspace code inside time namespace.
A page for timens offsets is allocated on time namespace construction.
Put that page into VVAR for tasks inside timens and zero page for
host processes.
As VDSO code is already optimized as much as possible in terms of speed,
any new if-condition in VDSO code is undesirable; the goal is to provide
two .so(s), as was originally suggested by Andy and Thomas:
- for host tasks with optimized-out clk_to_ns() without any penalty
- for processes inside timens with clk_to_ns()
For this purpose, define clk_to_ns() under CONFIG_TIME_NS.
To eliminate any performance regression, clk_to_ns() will be called
under static_branch with follow-up patches, that adds support for
patching vdso.
VDSO mappings are platform-specific, add Kconfig dependency for arch.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/Kconfig | 5 +++
arch/x86/Kconfig | 1 +
arch/x86/entry/vdso/vdso-layout.lds.S | 9 ++++-
arch/x86/entry/vdso/vdso2c.c | 3 ++
arch/x86/entry/vdso/vma.c | 12 +++++++
arch/x86/include/asm/vdso.h | 1 +
init/Kconfig | 1 +
lib/vdso/gettimeofday.c | 47 +++++++++++++++++++++++++++
8 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 719b27275f86..5ddb92e6bfe0 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -740,6 +740,11 @@ config HAVE_ARCH_NVRAM_OPS
config ISA_BUS_API
def_bool ISA
+config ARCH_HAS_VDSO_TIME_NS
+ bool
+ help
+ VDSO can add time-ns offsets without entering kernel.
+
#
# ABI hall of shame
#
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d685677d90f0..7ab810bc965d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -81,6 +81,7 @@ config X86
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VDSO_TIME_NS
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index 93c6dc7812d0..ba216527e59f 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -7,6 +7,12 @@
* This script controls its layout.
*/
+#ifdef CONFIG_TIME_NS
+# define TIMENS_SZ PAGE_SIZE
+#else
+# define TIMENS_SZ 0
+#endif
+
SECTIONS
{
/*
@@ -16,7 +22,7 @@ SECTIONS
* segment.
*/
- vvar_start = . - 3 * PAGE_SIZE;
+ vvar_start = . - (3 * PAGE_SIZE + TIMENS_SZ);
vvar_page = vvar_start;
/* Place all vvars at the offsets in asm/vvar.h. */
@@ -28,6 +34,7 @@ SECTIONS
pvclock_page = vvar_start + PAGE_SIZE;
hvclock_page = vvar_start + 2 * PAGE_SIZE;
+ timens_page = vvar_start + 3 * PAGE_SIZE;
. = SIZEOF_HEADERS;
diff --git a/arch/x86/entry/vdso/vdso2c.c b/arch/x86/entry/vdso/vdso2c.c
index ce67370d14e5..7380908045c7 100644
--- a/arch/x86/entry/vdso/vdso2c.c
+++ b/arch/x86/entry/vdso/vdso2c.c
@@ -75,12 +75,14 @@ enum {
sym_vvar_page,
sym_pvclock_page,
sym_hvclock_page,
+ sym_timens_page,
};
const int special_pages[] = {
sym_vvar_page,
sym_pvclock_page,
sym_hvclock_page,
+ sym_timens_page,
};
struct vdso_sym {
@@ -93,6 +95,7 @@ struct vdso_sym required_syms[] = {
[sym_vvar_page] = {"vvar_page", true},
[sym_pvclock_page] = {"pvclock_page", true},
[sym_hvclock_page] = {"hvclock_page", true},
+ [sym_timens_page] = {"timens_page", true},
{"VDSO32_NOTE_MASK", true},
{"__kernel_vsyscall", true},
{"__kernel_sigreturn", true},
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 2dc4f0b5481c..9bd66f84db5e 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -14,6 +14,7 @@
#include <linux/elf.h>
#include <linux/cpu.h>
#include <linux/ptrace.h>
+#include <linux/time_namespace.h>
#include <asm/pvclock.h>
#include <asm/vgtod.h>
#include <asm/proto.h>
@@ -23,6 +24,7 @@
#include <asm/desc.h>
#include <asm/cpufeature.h>
#include <clocksource/hyperv_timer.h>
+#include <asm/page.h>
#if defined(CONFIG_X86_64)
unsigned int __read_mostly vdso64_enabled = 1;
@@ -135,6 +137,16 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
if (tsc_pg && vclock_was_used(VCLOCK_HVCLOCK))
return vmf_insert_pfn(vma, vmf->address,
vmalloc_to_pfn(tsc_pg));
+ } else if (sym_offset == image->sym_timens_page) {
+ struct time_namespace *ns = current->nsproxy->time_ns;
+ unsigned long pfn;
+
+ if (!ns->offsets)
+ pfn = page_to_pfn(ZERO_PAGE(0));
+ else
+ pfn = page_to_pfn(virt_to_page(ns->offsets));
+
+ return vmf_insert_pfn(vma, vmf->address, pfn);
}
return VM_FAULT_SIGBUS;
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index dffdc12cc7d6..9d420c545607 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -21,6 +21,7 @@ struct vdso_image {
long sym_vvar_page;
long sym_pvclock_page;
long sym_hvclock_page;
+ long sym_timens_page;
long sym_VDSO32_NOTE_MASK;
long sym___kernel_sigreturn;
long sym___kernel_rt_sigreturn;
diff --git a/init/Kconfig b/init/Kconfig
index 525dc3ed86c4..7adf939eeaa8 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1074,6 +1074,7 @@ config UTS_NS
config TIME_NS
bool "TIME namespace"
+ depends on ARCH_HAS_VDSO_TIME_NS
default y
help
In this namespace boottime and monotonic clocks can be set.
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index e630e7ff57f1..8589c66ff3e7 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -7,6 +7,7 @@
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/hrtimer_defs.h>
+#include <linux/timens_offsets.h>
#include <vdso/datapage.h>
#include <vdso/helpers.h>
@@ -38,6 +39,48 @@ u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
}
#endif
+#ifdef CONFIG_TIME_NS
+extern u8 timens_page
+ __attribute__((visibility("hidden")));
+
+notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts)
+{
+ struct timens_offsets *timens = (struct timens_offsets *) &timens_page;
+ struct timespec64 *offset64;
+
+ switch (clk) {
+ case CLOCK_MONOTONIC:
+ case CLOCK_MONOTONIC_COARSE:
+ case CLOCK_MONOTONIC_RAW:
+ offset64 = &timens->monotonic;
+ break;
+ case CLOCK_BOOTTIME:
+ offset64 = &timens->boottime;
+ break;
+ default:
+ return;
+ }
+
+ /*
+ * The kernel allows to set a negative offset only if the current clock
+ * value in a namespace is positive, so the result tv_sec can't be
+ * negative here.
+ */
+ ts->tv_nsec += offset64->tv_nsec;
+ ts->tv_sec += offset64->tv_sec;
+ if (ts->tv_nsec >= NSEC_PER_SEC) {
+ ts->tv_nsec -= NSEC_PER_SEC;
+ ts->tv_sec++;
+ }
+ if (ts->tv_nsec < 0) {
+ ts->tv_nsec += NSEC_PER_SEC;
+ ts->tv_sec--;
+ }
+}
+#else
+notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts) {}
+#endif
+
static int do_hres(const struct vdso_data *vd, clockid_t clk,
struct __kernel_timespec *ts)
{
@@ -65,6 +108,8 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk,
ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
ts->tv_nsec = ns;
+ clk_to_ns(clk, ts);
+
return 0;
}
@@ -79,6 +124,8 @@ static void do_coarse(const struct vdso_data *vd, clockid_t clk,
ts->tv_sec = vdso_ts->sec;
ts->tv_nsec = vdso_ts->nsec;
} while (unlikely(vdso_read_retry(vd, seq)));
+
+ clk_to_ns(clk, ts);
}
static __maybe_unused int
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 22/36] x86/vdso: Add offsets page in vvar
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 19:21 ` Thomas Gleixner
2019-08-16 20:20 ` Dmitry Safonov
-1 siblings, 1 reply; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 19:21 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86,
Andrei Vagin
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> ---
> arch/Kconfig | 5 +++
> arch/x86/Kconfig | 1 +
> arch/x86/entry/vdso/vdso-layout.lds.S | 9 ++++-
> arch/x86/entry/vdso/vdso2c.c | 3 ++
> arch/x86/entry/vdso/vma.c | 12 +++++++
> arch/x86/include/asm/vdso.h | 1 +
> init/Kconfig | 1 +
> lib/vdso/gettimeofday.c | 47 +++++++++++++++++++++++++++
This needs to be split into the generic lib/vdso part and then x86 making
use of it.
> +#ifdef CONFIG_TIME_NS
This should be COMPILE_WITH_TIME_NS and not CONFIG_TIME_NS
> +extern u8 timens_page
> + __attribute__((visibility("hidden")));
> +
> +notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts)
This needs notrace because?
> +{
> + struct timens_offsets *timens = (struct timens_offsets *) &timens_page;
> + struct timespec64 *offset64;
> +
> + switch (clk) {
> + case CLOCK_MONOTONIC:
> + case CLOCK_MONOTONIC_COARSE:
> + case CLOCK_MONOTONIC_RAW:
> + offset64 = &timens->monotonic;
> + break;
> + case CLOCK_BOOTTIME:
> + offset64 = &timens->boottime;
> + break;
> + default:
> + return;
> + }
> +
> + /*
> + * The kernel allows to set a negative offset only if the current clock
> + * value in a namespace is positive, so the result tv_sec can't be
> + * negative here.
> + */
> + ts->tv_nsec += offset64->tv_nsec;
> + ts->tv_sec += offset64->tv_sec;
> + if (ts->tv_nsec >= NSEC_PER_SEC) {
> + ts->tv_nsec -= NSEC_PER_SEC;
> + ts->tv_sec++;
> + }
> + if (ts->tv_nsec < 0) {
> + ts->tv_nsec += NSEC_PER_SEC;
> + ts->tv_sec--;
> + }
That's broken for 32bit user space on 64bit hosts. On LE due to
misalignment and on BE because 32bit will read always 0.
> +}
> +#else
> +notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts) {}
> +#endif
> +
> static int do_hres(const struct vdso_data *vd, clockid_t clk,
> struct __kernel_timespec *ts)
> {
> @@ -65,6 +108,8 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk,
> ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
> ts->tv_nsec = ns;
>
> + clk_to_ns(clk, ts);
> +
> return 0;
> }
>
> @@ -79,6 +124,8 @@ static void do_coarse(const struct vdso_data *vd, clockid_t clk,
> ts->tv_sec = vdso_ts->sec;
> ts->tv_nsec = vdso_ts->nsec;
> } while (unlikely(vdso_read_retry(vd, seq)));
> +
> + clk_to_ns(clk, ts);
> }
>
> static __maybe_unused int
> --
> 2.22.0
>
>
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 22/36] x86/vdso: Add offsets page in vvar
2019-08-15 19:21 ` Thomas Gleixner
@ 2019-08-16 20:20 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-16 20:20 UTC (permalink / raw)
To: Thomas Gleixner, Dmitry Safonov
Cc: linux-kernel, Andrei Vagin, Adrian Reber, Andy Lutomirski,
Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86,
Andrei Vagin
Hi Thomas,
On 8/15/19 8:21 PM, Thomas Gleixner wrote:
> On Thu, 15 Aug 2019, Dmitry Safonov wrote:
>> ---
>> arch/Kconfig | 5 +++
>> arch/x86/Kconfig | 1 +
>> arch/x86/entry/vdso/vdso-layout.lds.S | 9 ++++-
>> arch/x86/entry/vdso/vdso2c.c | 3 ++
>> arch/x86/entry/vdso/vma.c | 12 +++++++
>> arch/x86/include/asm/vdso.h | 1 +
>> init/Kconfig | 1 +
>> lib/vdso/gettimeofday.c | 47 +++++++++++++++++++++++++++
>
> This needs to be split into the generic lib/vdso part and then x86 making
> use of it.
Ok
>> +#ifdef CONFIG_TIME_NS
>
> This should be COMPILE_WITH_TIME_NS and not CONFIG_TIME_NS
>
>> +extern u8 timens_page
>> + __attribute__((visibility("hidden")));
>> +
>> +notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts)
>
> This needs notrace because?
Heh, well it's alive from the time it was in arch/x86.
I believe, functions there had it since commit 23adec554a76 ("x86: add
notrace annotations to vsyscall"). Probably, lib/vdso is compiled
without mcount in the Makefile somewhere.
Will drop.
[..]
>> + /*
>> + * The kernel allows to set a negative offset only if the current clock
>> + * value in a namespace is positive, so the result tv_sec can't be
>> + * negative here.
>> + */
>> + ts->tv_nsec += offset64->tv_nsec;
>> + ts->tv_sec += offset64->tv_sec;
>> + if (ts->tv_nsec >= NSEC_PER_SEC) {
>> + ts->tv_nsec -= NSEC_PER_SEC;
>> + ts->tv_sec++;
>> + }
>> + if (ts->tv_nsec < 0) {
>> + ts->tv_nsec += NSEC_PER_SEC;
>> + ts->tv_sec--;
>> + }
>
> That's broken for 32bit user space on 64bit hosts. On LE due to
> misalignment and on BE because 32bit will read always 0.
Ugh, will look into that.
Thanks,
Dmitry
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-15 16:38 ` Dmitry Safonov
` (22 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
2019-08-16 15:23 ` Andy Lutomirski
-1 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
It will add a penalty for everybody as branch predictor may mispredict
the jump. Also there are instruction cache lines wasted on cmp/jmp.
Those effects of introducing time namespace are very much unwanted
having in mind how much work have been spent on micro-optimisation
vdso code.
The propose is to allocate a second vdso code with dynamically
patched out (disabled by static_branch) timens code on boot time.
Allocate another vdso and copy original code.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vdso2c.h | 2 +-
arch/x86/entry/vdso/vma.c | 113 +++++++++++++++++++++++++++++++++--
arch/x86/include/asm/vdso.h | 9 +--
3 files changed, 114 insertions(+), 10 deletions(-)
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index 7556bb70ed8b..885b988aea19 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -157,7 +157,7 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
}
fprintf(outfile, "\n};\n\n");
- fprintf(outfile, "const struct vdso_image %s = {\n", image_name);
+ fprintf(outfile, "struct vdso_image %s __ro_after_init = {\n", image_name);
fprintf(outfile, "\t.text = raw_data,\n");
fprintf(outfile, "\t.size = %lu,\n", mapping_size);
if (alt_sec) {
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 9bd66f84db5e..8a8211fd4cfc 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -30,26 +30,128 @@
unsigned int __read_mostly vdso64_enabled = 1;
#endif
-void __init init_vdso_image(const struct vdso_image *image)
+void __init init_vdso_image(struct vdso_image *image)
{
BUG_ON(image->size % PAGE_SIZE != 0);
apply_alternatives((struct alt_instr *)(image->text + image->alt),
(struct alt_instr *)(image->text + image->alt +
image->alt_len));
+#ifdef CONFIG_TIME_NS
+ image->text_timens = vmalloc_32(image->size);
+ if (WARN_ON(image->text_timens == NULL))
+ return;
+
+ memcpy(image->text_timens, image->text, image->size);
+#endif
}
struct linux_binprm;
+#ifdef CONFIG_TIME_NS
+static inline struct timens_offsets *current_timens_offsets(void)
+{
+ return current->nsproxy->time_ns->offsets;
+}
+
+static int vdso_check_timens(struct vm_area_struct *vma, bool *in_timens)
+{
+ struct task_struct *tsk;
+
+ if (likely(vma->vm_mm == current->mm)) {
+ *in_timens = !!current_timens_offsets();
+ return 0;
+ }
+
+ /*
+ * .fault() handler can be called over remote process through
+ * interfaces like /proc/$pid/mem or process_vm_{readv,writev}()
+ * Considering such access to vdso as a slow-path.
+ */
+
+#ifdef CONFIG_MEMCG
+ rcu_read_lock();
+
+ tsk = rcu_dereference(vma->vm_mm->owner);
+ if (tsk) {
+ task_lock(tsk);
+ /*
+ * Shouldn't happen: nsproxy is unset in exit_mm().
+ * Before that exit_mm() holds mmap_sem to set (mm = NULL).
+ * It's impossible to have a fault in task without mm
+ * and mmap_sem is taken during the fault.
+ */
+ if (WARN_ON_ONCE(tsk->nsproxy == NULL)) {
+ task_unlock(tsk);
+ rcu_read_unlock();
+ return -EIO;
+ }
+ *in_timens = !!tsk->nsproxy->time_ns->offsets;
+ task_unlock(tsk);
+ rcu_read_unlock();
+ return 0;
+ }
+ rcu_read_unlock();
+#endif
+
+ read_lock(&tasklist_lock);
+ for_each_process(tsk) {
+ struct task_struct *c;
+
+ if (tsk->flags & PF_KTHREAD)
+ continue;
+ for_each_thread(tsk, c) {
+ if (c->mm == vma->vm_mm)
+ goto found;
+ if (c->mm)
+ break;
+ }
+ }
+ read_unlock(&tasklist_lock);
+ return -ESRCH;
+
+found:
+ task_lock(tsk);
+ read_unlock(&tasklist_lock);
+ *in_timens = !!tsk->nsproxy->time_ns->offsets;
+ task_unlock(tsk);
+
+ return 0;
+}
+#else /* CONFIG_TIME_NS */
+static inline int vdso_check_timens(struct vm_area_struct *vma, bool *in_timens)
+{
+ *in_timens = false;
+ return 0;
+}
+static inline struct timens_offsets *current_timens_offsets(void)
+{
+ return NULL;
+}
+#endif /* CONFIG_TIME_NS */
+
static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
const struct vdso_image *image = vma->vm_mm->context.vdso_image;
+ unsigned long offset = vmf->pgoff << PAGE_SHIFT;
+ bool in_timens;
+ int err;
if (!image || (vmf->pgoff << PAGE_SHIFT) >= image->size)
return VM_FAULT_SIGBUS;
- vmf->page = virt_to_page(image->text + (vmf->pgoff << PAGE_SHIFT));
+ err = vdso_check_timens(vma, &in_timens);
+ if (err)
+ return VM_FAULT_SIGBUS;
+
+ WARN_ON_ONCE(in_timens && !image->text_timens);
+
+ if (in_timens && image->text_timens)
+ vmf->page = vmalloc_to_page(image->text_timens + offset);
+ else
+ vmf->page = virt_to_page(image->text + offset);
+
get_page(vmf->page);
return 0;
}
@@ -138,13 +240,14 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
return vmf_insert_pfn(vma, vmf->address,
vmalloc_to_pfn(tsc_pg));
} else if (sym_offset == image->sym_timens_page) {
- struct time_namespace *ns = current->nsproxy->time_ns;
+ /* We can fault only in current context for VM_PFNMAP mapping */
+ struct timens_offsets *offsets = current_timens_offsets();
unsigned long pfn;
- if (!ns->offsets)
+ if (!offsets)
pfn = page_to_pfn(ZERO_PAGE(0));
else
- pfn = page_to_pfn(virt_to_page(ns->offsets));
+ pfn = page_to_pfn(virt_to_page(offsets));
return vmf_insert_pfn(vma, vmf->address, pfn);
}
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index 9d420c545607..03f468c63a24 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -12,6 +12,7 @@
struct vdso_image {
void *text;
+ void *text_timens;
unsigned long size; /* Always a multiple of PAGE_SIZE */
unsigned long alt, alt_len;
@@ -30,18 +31,18 @@ struct vdso_image {
};
#ifdef CONFIG_X86_64
-extern const struct vdso_image vdso_image_64;
+extern struct vdso_image vdso_image_64;
#endif
#ifdef CONFIG_X86_X32
-extern const struct vdso_image vdso_image_x32;
+extern struct vdso_image vdso_image_x32;
#endif
#if defined CONFIG_X86_32 || defined CONFIG_COMPAT
-extern const struct vdso_image vdso_image_32;
+extern struct vdso_image vdso_image_32;
#endif
-extern void __init init_vdso_image(const struct vdso_image *image);
+extern void __init init_vdso_image(struct vdso_image *image);
extern int map_vdso_once(const struct vdso_image *image, unsigned long addr);
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-15 16:38 ` [PATCHv6 23/36] x86/vdso: Allocate timens vdso Dmitry Safonov
@ 2019-08-16 15:23 ` Andy Lutomirski
2019-08-16 20:10 ` Thomas Gleixner
0 siblings, 1 reply; 87+ messages in thread
From: Andy Lutomirski @ 2019-08-16 15:23 UTC (permalink / raw)
To: Dmitry Safonov, linux-kernel
Cc: Dmitry Safonov, Adrian Reber, Andrei Vagin, Arnd Bergmann,
Christian Brauner, Cyrill Gorcunov, Eric W. Biederman,
H. Peter Anvin, Ingo Molnar, Jann Horn, Jeff Dike, Oleg Nesterov,
Pavel Emelyanov, Shuah Khan, Thomas Gleixner, Vincenzo Frascino,
containers, criu, linux-api, x86
On 8/15/19 9:38 AM, Dmitry Safonov wrote:
> As it has been discussed on timens RFC, adding a new conditional branch
> `if (inside_time_ns)` on VDSO for all processes is undesirable.
> It will add a penalty for everybody as branch predictor may mispredict
> the jump. Also there are instruction cache lines wasted on cmp/jmp.
>
> Those effects of introducing time namespace are very much unwanted
> having in mind how much work have been spent on micro-optimisation
> vdso code.
>
> The propose is to allocate a second vdso code with dynamically
> patched out (disabled by static_branch) timens code on boot time.
>
> Allocate another vdso and copy original code.
I'm unconvinced that any of this magic is wise. I think you should make
a special timens vvar page that causes the normal fastpath to fail
(using a special vclock mode, a special seq value, or a special "last"
value) and then make the failure path detect that timens is in use and
use the timens path.
--Andy
^ permalink raw reply [flat|nested] 87+ messages in thread
* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-16 15:23 ` Andy Lutomirski
@ 2019-08-16 20:10 ` Thomas Gleixner
2019-08-16 22:47 ` Dmitry Safonov
0 siblings, 1 reply; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-16 20:10 UTC (permalink / raw)
To: Andy Lutomirski
Cc: Dmitry Safonov, linux-kernel, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Fri, 16 Aug 2019, Andy Lutomirski wrote:
> On 8/15/19 9:38 AM, Dmitry Safonov wrote:
> > As it has been discussed on timens RFC, adding a new conditional branch
> > `if (inside_time_ns)` on VDSO for all processes is undesirable.
> > It will add a penalty for everybody as branch predictor may mispredict
> > the jump. Also there are instruction cache lines wasted on cmp/jmp.
> >
> > Those effects of introducing time namespace are very much unwanted
> > having in mind how much work have been spent on micro-optimisation
> > vdso code.
> >
> > The propose is to allocate a second vdso code with dynamically
> > patched out (disabled by static_branch) timens code on boot time.
> >
> > Allocate another vdso and copy original code.
>
>
> I'm unconvinced that any of this magic is wise. I think you should make a
> special timens vvar page that causes the normal fastpath to fail (using a
> special vclock mode, a special seq value, or a special "last" value) and then
> make the failure path detect that timens is in use and use the timens path.
My initial suggestion still stands. Do that at compile time. It really does
not matter whether we have another 2 or 3 variants of vdso binaries.
Use it and be done with it. No special magic, just straight forward
decisions to use a timens capable VDSO or not.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-16 20:10 ` Thomas Gleixner
@ 2019-08-16 22:47 ` Dmitry Safonov
2019-08-18 16:21 ` Thomas Gleixner
0 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-16 22:47 UTC (permalink / raw)
To: Thomas Gleixner, Andy Lutomirski
Cc: Dmitry Safonov, linux-kernel, Adrian Reber, Andrei Vagin,
Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
Hi Andy, Thomas,
thank you very much for your time and the reviews, appreciate that.
On 8/16/19 9:10 PM, Thomas Gleixner wrote:
> On Fri, 16 Aug 2019, Andy Lutomirski wrote:
[..]
>> I'm unconvinced that any of this magic is wise. I think you should make a
>> special timens vvar page that causes the normal fastpath to fail (using a
>> special vclock mode, a special seq value, or a special "last" value) and then
>> make the failure path detect that timens is in use and use the timens path.
I see. That's so clever, it haven't come on my mind.
Hmm, is that better because of the price of 5-byte NOP?
I'm a bit afraid to complicate that seq/vclock logic more..
So, what I'm driving at is would you change your mind if timens still
had boot-time dynamic patching but without introducing NOP?
We've got the point that you want to have no penalty at all for host
tasks [on RFC reply] by introducing `if` as trashing cache and branch
predictor, but I wasn't sure if NOP is also unacceptable.
At that moment we had a "plan B" with something that was half-wittedly
called "retcalls". The basic idea is that all that the timens brings
into vdso are calls clk_to_ns(), which are all placed in tails of
functions. So, if we could just memcpy() function returns in host vdso
over introduced time-ns tail calls - it would be a very same code that
lied before. There is a draft of those [1], that actually works on x86
on both mine and Andrei's machines.
Consulting with Andrei, I've decided that we better stick to
static_branchs as they are well known and have already backends for
other architectures. We probably mistakenly decided that a price of NOP
on scalar machines is negligible and would be acceptable.
Would those self-invented "retcalls" be something that could be reviewed
and potentially accepted in further iterations?
[1]
https://github.com/0x7f454c46/linux/commit/ab0eeb646f43#diff-c22e1e73e7367f371e1f12e3877ea12f
> My initial suggestion still stands. Do that at compile time. It really does
> not matter whether we have another 2 or 3 variants of vdso binaries.
>
> Use it and be done with it. No special magic, just straight forward
> decisions to use a timens capable VDSO or not.
I believe that was something we did in version 1 of the patches set.
It doesn't sound like a rocket science to do, but it resulted in a
couple of ugly patches.
The post-attempt notes about downsides of doing it compile-time are:
1. There is additional .so for each vdso: 64-bit, ia32, x32. The same
for every architecture to-be supported. It adds rules in Makefiles. [2]
2. If we still intend to keep setns() working without exec(), function
entries on both host/namespace vdso should be aligned to each other [3].
That results in a patch to vdso2c to generate offsets [4, 5] and in
linker magic to align another vdso [6].
3. As unexpected consequence, we also need to align local functions on
vdso [7].
So, it might be all related to my lack of skills, but it seems to bring
some big amount of complexity into build process. And in my point of
view, major issue is that it would not scale easily when the day will
come and there will be a need to introduce another vdso.so. As I didn't
want to be the guy that happens to be remembered as "he wrote this
unmaintainable pile of garbage", I've taken dynamic patching approach
that is done once a boot time.
Regardless, we both with Andrei want to improve the patches set and make
it acceptable and easy to maintain in future. I hope, that our effort to
do that is visible through evolution of patches. And we're very glad
that we've constructive critics and such patient maintainers.
So, if I'm mistaken in those points about compile-time vdso(s), or you
have in mind a plan how-to avoid those, I'd appreciate and rework it to
that direction.
[2] lkml.kernel.org/r/20190206001107.16488-14-dima@arista.com
[3] lkml.kernel.org/r/20190206001107.16488-15-dima@arista.com
[4] lkml.kernel.org/r/20190206001107.16488-16-dima@arista.com
[5] lkml.kernel.org/r/20190206001107.16488-17-dima@arista.com
[6] lkml.kernel.org/r/20190206001107.16488-19-dima@arista.com
[7] lkml.kernel.org/r/20190206001107.16488-20-dima@arista.com
Thanks,
Dmitry
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-16 22:47 ` Dmitry Safonov
@ 2019-08-18 16:21 ` Thomas Gleixner
2019-08-18 16:24 ` Thomas Gleixner
2019-08-19 14:15 ` Dmitry Safonov
0 siblings, 2 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-18 16:21 UTC (permalink / raw)
To: Dmitry Safonov
Cc: Andy Lutomirski, Dmitry Safonov, linux-kernel, Adrian Reber,
Andrei Vagin, Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
Dmitry,
On Fri, 16 Aug 2019, Dmitry Safonov wrote:
> On 8/16/19 9:10 PM, Thomas Gleixner wrote:
> > On Fri, 16 Aug 2019, Andy Lutomirski wrote:
> [..]
> >> I'm unconvinced that any of this magic is wise. I think you should make a
> >> special timens vvar page that causes the normal fastpath to fail (using a
> >> special vclock mode, a special seq value, or a special "last" value) and then
> >> make the failure path detect that timens is in use and use the timens path.
>
> I see. That's so clever, it haven't come on my mind.
> Hmm, is that better because of the price of 5-byte NOP?
> I'm a bit afraid to complicate that seq/vclock logic more..
See below.
> > My initial suggestion still stands. Do that at compile time. It really does
> > not matter whether we have another 2 or 3 variants of vdso binaries.
> >
> > Use it and be done with it. No special magic, just straight forward
> > decisions to use a timens capable VDSO or not.
>
> I believe that was something we did in version 1 of the patches set.
> It doesn't sound like a rocket science to do, but it resulted in a
> couple of ugly patches.
>
> The post-attempt notes about downsides of doing it compile-time are:
>
> 1. There is additional .so for each vdso: 64-bit, ia32, x32. The same
> for every architecture to-be supported. It adds rules in Makefiles. [2]
> 2. If we still intend to keep setns() working without exec(), function
> entries on both host/namespace vdso should be aligned to each other [3].
> That results in a patch to vdso2c to generate offsets [4, 5] and in
> linker magic to align another vdso [6].
> 3. As unexpected consequence, we also need to align local functions on
> vdso [7].
>
> So, it might be all related to my lack of skills, but it seems to bring
> some big amount of complexity into build process. And in my point of
> view, major issue is that it would not scale easily when the day will
> come and there will be a need to introduce another vdso.so. As I didn't
> want to be the guy that happens to be remembered as "he wrote this
> unmaintainable pile of garbage", I've taken dynamic patching approach
> that is done once a boot time.
Fair enough. Did not think about that part.
> Regardless, we both with Andrei want to improve the patches set and make
> it acceptable and easy to maintain in future. I hope, that our effort to
> do that is visible through evolution of patches. And we're very glad
> that we've constructive critics and such patient maintainers.
I'm happy to review well written stuff which makes progress and takes
review comments into account or the submitter discusses them for
resolution.
> So, if I'm mistaken in those points about compile-time vdso(s), or you
> have in mind a plan how-to avoid those, I'd appreciate and rework it to
> that direction.
Coming back to Andy's idea. Create your time namespace page as an exact
copy of the vdso data page. When the page is created do:
memset(p->vdso_data, 0, sizeof(p->vdso_data));
p->vdso_data[0].clock_mode = CLOCK_TIMENS;
p->vdso_data[0].seq = 1;
/* Store the namespace offsets in basetime */
p->vdso_data[0].basetime[CLOCK_MONOTONIC].sec = myns->mono_sec;
p->vdso_data[0].basetime[CLOCK_MONOTONIC].nsec = myns->mono_nsec;
p->vdso_data[0].basetime[CLOCK_BOOTTIME].sec = myns->boot_sec;
p->vdso_data[0].basetime[CLOCK_BOOTTIME].nsec = myns->boot_nsec;
p->vdso_data[1].clock_mode = CLOCK_TIMENS;
p->vdso_data[1].seq = 1;
For a normal task the VVAR pages are installed in the normal ordering:
VVAR
PVCLOCK
HVCLOCK
TIMENS <- Not really required
Now for a timens task you install the pages in the following order
TIMENS
PVCLOCK
HVCLOCK
VVAR
The check for vdso_data->clock_mode is in the unlikely path of the now open
coded seq begin magic. So for the non-timens case most of the time 'seq' is
even, so the branch is not taken.
If 'seq' is odd, i.e. a concurrent update is in progress, the extra check
for vdso_data->clock_mode is a non-issue. The task is spin waiting for the
update to finish and for 'seq' to become even anyway.
Patch below. I tested this with the normal order and by installing a
'timens' page unconditionally for all processes. I'll reply with the timens
testing hacks so you can see what I did.
The test results are pretty good.
Base (upstream) + VDSO patch + timens page
MONO 30ns 30ns 32ns
REAL 30ns 30ns 32ns
BOOT 30ns 30ns 32ns
MONOCOARSE 7ns 8ns 10ns
REALCOARSE 7ns 8ns 10ns
TAI 30ns 30ns 32ns
MONORAW 30ns 30ns 32ns
So except for the coarse clocks there is no change when the timens page is
not used, i.e. the regular VVAR page is at the proper place. But that's on
one machine, a different one showed an effect in the noise range. I'm not
worried about that as the VDSO behaviour varies depending on micro
architecture anyway.
With timens enabled the performance hit (cache hot microbenchmark) is
somewhere in the range of 5-7% when looking at the perf counters
numbers. The hit for the coarse accessors is larger obviously because the
overhead is constant time.
I did a quick comparison of the array vs. switch case (what you used for
your clk_to_ns() helper). The switch case is slower.
So I rather go for the array based approach. It's simpler code and the
I-cache footprint is smaller and no conditional branches involved.
That means your timens_to_host() and host_to_timens() conversion functions
should just use that special VDSO page and do the same array based
unconditional add/sub of the clock specific offset.
Thanks,
tglx
8<-----------------
Subject: lib/vdso: Prepare for time namespace support
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 18 Aug 2019 16:53:06 +0200
To support time namespaces in the vdso with a minimal impact on regular non
time namespace affected tasks, the namespace handling needs to be hidden in
a slow path.
The most obvious place is vdso_seq_begin(). If a task belongs to a time
namespace then the VVAR page which contains the system wide vdso data is
replaced with a namespace specific page which has the same layout as the
VVAR page. That page has vdso_data->seq set to 1 to enforce the slow path
and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time
namespace handling path.
The extra check in the case that vdso_data->seq is odd, e.g. a concurrent
update of the vdso data is in progress, is not really affecting regular
tasks which are not part of a time namespace as the task is spin waiting
for the update to finish and vdso_data->seq to become even again.
If a time namespace task hits that code path, it invokes the corresponding
time getter function which retrieves the real VVAR page, reads host time
and then adds the offset for the requested clock which is stored in the
special VVAR page.
If VDSO time namespace support is disabled the whole magic is compiled out.
Initial testing shows that the disabled case is almost identical to the
host case which does not take the slow timens path. With the special timens
page installed the performance hit is constant time and in the range of
5-7%.
For the vdso functions which are not using the sequence count an
unconditional check for vdso_data->clock_mode is added which switches to
the real vdso when the clock_mode is VCLOCK_TIMENS.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/time.h | 6 ++
include/vdso/datapage.h | 19 ++++++-
lib/vdso/Kconfig | 6 ++
lib/vdso/gettimeofday.c | 128 ++++++++++++++++++++++++++++++++++++++++++++++--
4 files changed, 155 insertions(+), 4 deletions(-)
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -96,4 +96,10 @@ static inline bool itimerspec64_valid(co
*/
#define time_after32(a, b) ((s32)((u32)(b) - (u32)(a)) < 0)
#define time_before32(b, a) time_after32(a, b)
+
+struct timens_offset {
+ s64 sec;
+ u64 nsec;
+};
+
#endif
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -21,6 +21,8 @@
#define CS_RAW 1
#define CS_BASES (CS_RAW + 1)
+#define VCLOCK_TIMENS UINT_MAX
+
/**
* struct vdso_timestamp - basetime per clock_id
* @sec: seconds
@@ -48,6 +50,7 @@ struct vdso_timestamp {
* @mult: clocksource multiplier
* @shift: clocksource shift
* @basetime[clock_id]: basetime per clock_id
+ * @offset[clock_id]: time namespace offset per clock_id
* @tz_minuteswest: minutes west of Greenwich
* @tz_dsttime: type of DST correction
* @hrtimer_res: hrtimer resolution
@@ -55,6 +58,17 @@ struct vdso_timestamp {
*
* vdso_data will be accessed by 64 bit and compat code at the same time
* so we should be careful before modifying this structure.
+ *
+ * @basetime is used to store the base time for the system wide time getter
+ * VVAR page.
+ *
+ * @offset is used by the special time namespace VVAR pages which are
+ * installed instead of the real VVAR page. These namespace pages must set
+ * @seq to 1 and @clock_mode to VLOCK_TIMENS to force the code into the
+ * time namespace slow path. The namespace aware functions retrieve the
+ * real system wide VVAR page, read host time and add the per clock offset.
+ * For clocks which are not affected by time namespace adjustement the
+ * offset must be zero.
*/
struct vdso_data {
u32 seq;
@@ -65,7 +79,10 @@ struct vdso_data {
u32 mult;
u32 shift;
- struct vdso_timestamp basetime[VDSO_BASES];
+ union {
+ struct vdso_timestamp basetime[VDSO_BASES];
+ struct timens_offset offset[VDSO_BASES];
+ };
s32 tz_minuteswest;
s32 tz_dsttime;
--- a/lib/vdso/Kconfig
+++ b/lib/vdso/Kconfig
@@ -33,4 +33,10 @@ config CROSS_COMPILE_COMPAT_VDSO
If a 64 bit compiler (i.e. x86_64) can compile the VDSO for
32 bit, it does not need to define this parameter.
+config VDSO_TIMENS
+ bool
+ help
+ Selected by architectures which support time namespaces in the
+ VDSO
+
endif
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -38,6 +38,51 @@ u64 vdso_calc_delta(u64 cycles, u64 last
}
#endif
+#ifndef CONFIG_VDSO_TIMENS
+static __always_inline
+const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
+{
+ return NULL;
+}
+#endif
+
+static int do_hres_ns(const struct vdso_data *vdns, clockid_t clk,
+ struct __kernel_timespec *ts)
+{
+ const struct vdso_data *vd = __arch_get_timens_vdso_data(vdns);
+ const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
+ const struct timens_offset *offs = &vdns->offset[clk];
+ u64 cycles, last, ns;
+ s64 sec;
+ u32 seq;
+
+ do {
+ seq = vdso_read_begin(vd);
+ cycles = __arch_get_hw_counter(vd->clock_mode);
+ ns = vdso_ts->nsec;
+ last = vd->cycle_last;
+ if (unlikely((s64)cycles < 0))
+ return -1;
+
+ ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult);
+ ns >>= vd->shift;
+ sec = vdso_ts->sec;
+ } while (unlikely(vdso_read_retry(vd, seq)));
+
+ /* Add the namespace offset */
+ sec += offs->sec;
+ ns += offs->nsec;
+
+ /*
+ * Do this outside the loop: a race inside the loop could result
+ * in __iter_div_u64_rem() being extremely slow.
+ */
+ ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
+ ts->tv_nsec = ns;
+
+ return 0;
+}
+
static int do_hres(const struct vdso_data *vd, clockid_t clk,
struct __kernel_timespec *ts)
{
@@ -46,7 +91,28 @@ static int do_hres(const struct vdso_dat
u32 seq;
do {
- seq = vdso_read_begin(vd);
+ /*
+ * Open coded to handle VCLOCK_TIMENS. Time namespace
+ * enabled tasks have a special VVAR page installed which
+ * has vd->seq set to 1 and vd->clock_mode set to
+ * VCLOCK_TIMENS. For non time namespace affected tasks
+ * this does not affect performance because if vd->seq is
+ * odd, i.e. a concurrent update is in progress the extra
+ * check for vd->clock_mode is just a few extra
+ * instructions while spin waiting for vd->seq to become
+ * even again.
+ */
+ while (1) {
+ seq = READ_ONCE(vd->seq);
+ if (likely(!(seq & 1)))
+ break;
+ if (IS_ENABLED(CONFIG_VDSO_TIMENS) &&
+ vd->clock_mode == VCLOCK_TIMENS)
+ return do_hres_ns(vd, clk, ts);
+ cpu_relax();
+ }
+ smp_rmb();
+
cycles = __arch_get_hw_counter(vd->clock_mode);
ns = vdso_ts->nsec;
last = vd->cycle_last;
@@ -68,6 +134,34 @@ static int do_hres(const struct vdso_dat
return 0;
}
+static void do_coarse_ns(const struct vdso_data *vdns, clockid_t clk,
+ struct __kernel_timespec *ts)
+{
+ const struct vdso_data *vd = __arch_get_timens_vdso_data(vdns);
+ const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
+ const struct timens_offset *offs = &vdns->offset[clk];
+ u64 nsec;
+ s64 sec;
+ s32 seq;
+
+ do {
+ seq = vdso_read_begin(vd);
+ sec = vdso_ts->sec;
+ nsec = vdso_ts->nsec;
+ } while (unlikely(vdso_read_retry(vd, seq)));
+
+ /* Add the namespace offset */
+ sec += offs->sec;
+ nsec += offs->nsec;
+
+ /*
+ * Do this outside the loop: a race inside the loop could result
+ * in __iter_div_u64_rem() being extremely slow.
+ */
+ ts->tv_sec = sec + __iter_div_u64_rem(nsec, NSEC_PER_SEC, &nsec);
+ ts->tv_nsec = nsec;
+}
+
static void do_coarse(const struct vdso_data *vd, clockid_t clk,
struct __kernel_timespec *ts)
{
@@ -75,7 +169,23 @@ static void do_coarse(const struct vdso_
u32 seq;
do {
- seq = vdso_read_begin(vd);
+ /*
+ * Open coded to handle VCLOCK_TIMENS. See comment in
+ * do_hres().
+ */
+ while (1) {
+ seq = READ_ONCE(vd->seq);
+ if (likely(!(seq & 1)))
+ break;
+ if (IS_ENABLED(CONFIG_VDSO_TIMENS) &&
+ vd->clock_mode == VCLOCK_TIMENS) {
+ do_coarse_ns(vd, clk, ts);
+ return;
+ }
+ cpu_relax();
+ }
+ smp_rmb();
+
ts->tv_sec = vdso_ts->sec;
ts->tv_nsec = vdso_ts->nsec;
} while (unlikely(vdso_read_retry(vd, seq)));
@@ -156,6 +266,10 @@ static __maybe_unused int
}
if (unlikely(tz != NULL)) {
+ if (IS_ENABLED(CONFIG_VDSO_TIMENS) &&
+ vd->clock_mode == VCLOCK_TIMENS)
+ vd = __arch_get_timens_vdso_data(vd);
+
tz->tz_minuteswest = vd[CS_HRES_COARSE].tz_minuteswest;
tz->tz_dsttime = vd[CS_HRES_COARSE].tz_dsttime;
}
@@ -167,7 +281,12 @@ static __maybe_unused int
static __maybe_unused time_t __cvdso_time(time_t *time)
{
const struct vdso_data *vd = __arch_get_vdso_data();
- time_t t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec);
+ time_t t;
+
+ if (IS_ENABLED(CONFIG_VDSO_TIMENS) && vd->clock_mode == VCLOCK_TIMENS)
+ vd = __arch_get_timens_vdso_data(vd);
+
+ t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec);
if (time)
*time = t;
@@ -189,6 +308,9 @@ int __cvdso_clock_getres_common(clockid_
if (unlikely((u32) clock >= MAX_CLOCKS))
return -1;
+ if (IS_ENABLED(CONFIG_VDSO_TIMENS) && vd->clock_mode == VCLOCK_TIMENS)
+ vd = __arch_get_timens_vdso_data(vd);
+
hrtimer_res = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
/*
* Convert the clockid to a bitmask and use it to check which
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-18 16:21 ` Thomas Gleixner
@ 2019-08-18 16:24 ` Thomas Gleixner
2019-08-18 16:29 ` Thomas Gleixner
2019-08-19 14:15 ` Dmitry Safonov
1 sibling, 1 reply; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-18 16:24 UTC (permalink / raw)
To: Dmitry Safonov
Cc: Andy Lutomirski, Dmitry Safonov, linux-kernel, Adrian Reber,
Andrei Vagin, Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Sun, 18 Aug 2019, Thomas Gleixner wrote:
>
> Patch below. I tested this with the normal order and by installing a
> 'timens' page unconditionally for all processes. I'll reply with the timens
> testing hacks so you can see what I did.
First hack...
Thanks,
tglx
8<-----------------
Subject: x86/vdso: Hack to enable time name space for testing
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 18 Aug 2019 16:42:26 +0200
Select CONFIG_VDSO_TIMENS and prepare for the extra magic time namespace
vvar page. The fault handler is not handling it yet as the path is never
taken (hopefully)
Not-Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/Kconfig | 1 +
arch/x86/entry/vdso/vdso-layout.lds.S | 3 ++-
arch/x86/entry/vdso/vdso2c.c | 3 +++
arch/x86/include/asm/vdso.h | 1 +
arch/x86/include/asm/vdso/gettimeofday.h | 9 +++++++++
5 files changed, 16 insertions(+), 1 deletion(-)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -224,6 +224,7 @@ config X86
select VIRT_TO_BUS
select X86_FEATURE_NAMES if PROC_FS
select PROC_PID_ARCH_STATUS if PROC_FS
+ select VDSO_TIMENS
config INSTRUCTION_DECODER
def_bool y
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -16,7 +16,7 @@ SECTIONS
* segment.
*/
- vvar_start = . - 3 * PAGE_SIZE;
+ vvar_start = . - 4 * PAGE_SIZE;
vvar_page = vvar_start;
/* Place all vvars at the offsets in asm/vvar.h. */
@@ -28,6 +28,7 @@ SECTIONS
pvclock_page = vvar_start + PAGE_SIZE;
hvclock_page = vvar_start + 2 * PAGE_SIZE;
+ timens_page = vvar_start + 3 * PAGE_SIZE;
. = SIZEOF_HEADERS;
--- a/arch/x86/entry/vdso/vdso2c.c
+++ b/arch/x86/entry/vdso/vdso2c.c
@@ -75,12 +75,14 @@ enum {
sym_vvar_page,
sym_pvclock_page,
sym_hvclock_page,
+ sym_timens_page,
};
const int special_pages[] = {
sym_vvar_page,
sym_pvclock_page,
sym_hvclock_page,
+ sym_timens_page,
};
struct vdso_sym {
@@ -93,6 +95,7 @@ struct vdso_sym required_syms[] = {
[sym_vvar_page] = {"vvar_page", true},
[sym_pvclock_page] = {"pvclock_page", true},
[sym_hvclock_page] = {"hvclock_page", true},
+ [sym_timens_page] = {"timens_page", true},
{"VDSO32_NOTE_MASK", true},
{"__kernel_vsyscall", true},
{"__kernel_sigreturn", true},
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -21,6 +21,7 @@ struct vdso_image {
long sym_vvar_page;
long sym_pvclock_page;
long sym_hvclock_page;
+ long sym_timens_page;
long sym_VDSO32_NOTE_MASK;
long sym___kernel_sigreturn;
long sym___kernel_rt_sigreturn;
--- a/arch/x86/include/asm/vdso/gettimeofday.h
+++ b/arch/x86/include/asm/vdso/gettimeofday.h
@@ -265,6 +265,15 @@ static __always_inline const struct vdso
return __vdso_data;
}
+/* HACK .... */
+#define VDSO_TIMENS_PAGEOFFSET (3 * PAGE_SIZE)
+
+static __always_inline
+const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
+{
+ return (void *)vd + VDSO_TIMENS_PAGEOFFSET;
+}
+
/*
* x86 specific delta calculation.
*
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-18 16:24 ` Thomas Gleixner
@ 2019-08-18 16:29 ` Thomas Gleixner
0 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-18 16:29 UTC (permalink / raw)
To: Dmitry Safonov
Cc: Andy Lutomirski, Dmitry Safonov, linux-kernel, Adrian Reber,
Andrei Vagin, Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Sun, 18 Aug 2019, Thomas Gleixner wrote:
> On Sun, 18 Aug 2019, Thomas Gleixner wrote:
> >
> > Patch below. I tested this with the normal order and by installing a
> > 'timens' page unconditionally for all processes. I'll reply with the timens
> > testing hacks so you can see what I did.
>
> First hack...
And the second one.
Thanks,
tglx
8<-----------------
Subject: x86/vdso: Hack to test the time namespace path
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 18 Aug 2019 16:49:00 +0200
Install a special TIMENS vvar page which forces the VDSO to take the time
namespace path for testing.
Not-Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/entry/vdso/vma.c | 34 +++++++++++++++++++++++++++++++++-
1 file changed, 33 insertions(+), 1 deletion(-)
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -84,6 +84,33 @@ static int vdso_mremap(const struct vm_s
return 0;
}
+/* Hack for testing */
+static struct page *vdso_timens_page;
+
+static int __init init_vdso_timens(void)
+{
+ struct vdso_data *vdata;
+ void *va;
+
+ vdso_timens_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!vdso_timens_page)
+ return -ENOMEM;
+
+ /* Hack: vdso data is at offset 0x80 in the page ... */
+ va = page_address(vdso_timens_page);
+ vdata = (struct vdso_data *)(va + 0x80);
+
+ vdata[0].seq = 1;
+ vdata[0].clock_mode = UINT_MAX;
+ vdata[1].seq = 1;
+ vdata[1].clock_mode = UINT_MAX;
+
+ /* All offsets are zero */
+
+ return 0;
+}
+subsys_initcall(init_vdso_timens);
+
static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
@@ -106,7 +133,7 @@ static vm_fault_t vvar_fault(const struc
if (sym_offset == 0)
return VM_FAULT_SIGBUS;
- if (sym_offset == image->sym_vvar_page) {
+ if (sym_offset == image->sym_timens_page) {
return vmf_insert_pfn(vma, vmf->address,
__pa_symbol(&__vvar_page) >> PAGE_SHIFT);
} else if (sym_offset == image->sym_pvclock_page) {
@@ -123,6 +150,11 @@ static vm_fault_t vvar_fault(const struc
if (tsc_pg && vclock_was_used(VCLOCK_HVCLOCK))
return vmf_insert_pfn(vma, vmf->address,
vmalloc_to_pfn(tsc_pg));
+ } else if (sym_offset == image->sym_vvar_page) {
+ unsigned long pfn;
+
+ pfn = page_to_pfn(vdso_timens_page);
+ return vmf_insert_pfn(vma, vmf->address, pfn);
}
return VM_FAULT_SIGBUS;
^ permalink raw reply [flat|nested] 87+ messages in thread
* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-18 16:21 ` Thomas Gleixner
2019-08-18 16:24 ` Thomas Gleixner
@ 2019-08-19 14:15 ` Dmitry Safonov
2019-08-19 14:44 ` Thomas Gleixner
1 sibling, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-19 14:15 UTC (permalink / raw)
To: Thomas Gleixner, Andy Lutomirski
Cc: Dmitry Safonov, linux-kernel, Adrian Reber, Andrei Vagin,
Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
Hi Thomas,
On 8/18/19 5:21 PM, Thomas Gleixner wrote:
[..]
> I'm happy to review well written stuff which makes progress and takes
> review comments into account or the submitter discusses them for
> resolution.
Thanks again for both your and Andy time!
[..]
> Coming back to Andy's idea. Create your time namespace page as an exact
> copy of the vdso data page. When the page is created do:
>
> memset(p->vdso_data, 0, sizeof(p->vdso_data));
> p->vdso_data[0].clock_mode = CLOCK_TIMENS;
> p->vdso_data[0].seq = 1;
>
> /* Store the namespace offsets in basetime */
> p->vdso_data[0].basetime[CLOCK_MONOTONIC].sec = myns->mono_sec;
> p->vdso_data[0].basetime[CLOCK_MONOTONIC].nsec = myns->mono_nsec;
> p->vdso_data[0].basetime[CLOCK_BOOTTIME].sec = myns->boot_sec;
> p->vdso_data[0].basetime[CLOCK_BOOTTIME].nsec = myns->boot_nsec;
>
> p->vdso_data[1].clock_mode = CLOCK_TIMENS;
> p->vdso_data[1].seq = 1;
>
> For a normal task the VVAR pages are installed in the normal ordering:
>
> VVAR
> PVCLOCK
> HVCLOCK
> TIMENS <- Not really required
>
> Now for a timens task you install the pages in the following order
>
> TIMENS
> PVCLOCK
> HVCLOCK
> VVAR
>
> The check for vdso_data->clock_mode is in the unlikely path of the now open
> coded seq begin magic. So for the non-timens case most of the time 'seq' is
> even, so the branch is not taken.
>
> If 'seq' is odd, i.e. a concurrent update is in progress, the extra check
> for vdso_data->clock_mode is a non-issue. The task is spin waiting for the
> update to finish and for 'seq' to become even anyway.
>
> Patch below. I tested this with the normal order and by installing a
> 'timens' page unconditionally for all processes. I'll reply with the timens
> testing hacks so you can see what I did.
>
> The test results are pretty good.
>
> Base (upstream) + VDSO patch + timens page
>
> MONO 30ns 30ns 32ns
> REAL 30ns 30ns 32ns
> BOOT 30ns 30ns 32ns
> MONOCOARSE 7ns 8ns 10ns
> REALCOARSE 7ns 8ns 10ns
> TAI 30ns 30ns 32ns
> MONORAW 30ns 30ns 32ns
>
> So except for the coarse clocks there is no change when the timens page is
> not used, i.e. the regular VVAR page is at the proper place. But that's on
> one machine, a different one showed an effect in the noise range. I'm not
> worried about that as the VDSO behaviour varies depending on micro
> architecture anyway.
>
> With timens enabled the performance hit (cache hot microbenchmark) is
> somewhere in the range of 5-7% when looking at the perf counters
> numbers. The hit for the coarse accessors is larger obviously because the
> overhead is constant time.
>
> I did a quick comparison of the array vs. switch case (what you used for
> your clk_to_ns() helper). The switch case is slower.
>
> So I rather go for the array based approach. It's simpler code and the
> I-cache footprint is smaller and no conditional branches involved.
>
> That means your timens_to_host() and host_to_timens() conversion functions
> should just use that special VDSO page and do the same array based
> unconditional add/sub of the clock specific offset.
I was a bit scarred that clock_mode change would result in some complex
logic, but your patch showed me that it's definitely not so black as I
was painting it.
Will rework the patches set with Andrei based on your and Andy's
suggestions and patches.
Thanks,
Dmitry
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 23/36] x86/vdso: Allocate timens vdso
2019-08-19 14:15 ` Dmitry Safonov
@ 2019-08-19 14:44 ` Thomas Gleixner
0 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-19 14:44 UTC (permalink / raw)
To: Dmitry Safonov
Cc: Andy Lutomirski, Dmitry Safonov, linux-kernel, Adrian Reber,
Andrei Vagin, Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
Dmitry,
On Mon, 19 Aug 2019, Dmitry Safonov wrote:
> On 8/18/19 5:21 PM, Thomas Gleixner wrote:
> > That means your timens_to_host() and host_to_timens() conversion functions
> > should just use that special VDSO page and do the same array based
> > unconditional add/sub of the clock specific offset.
>
> I was a bit scarred that clock_mode change would result in some complex
> logic, but your patch showed me that it's definitely not so black as I
> was painting it.
Right. It took me a while to find the right spot which does not affect the
non-timens path and at the same time gives a reasonable result for the
timens case.
One thing occured to me while doing that vvar_fault() hack for testing. For
the timens case it will hit
if (sym_offset == image->sym_vvar_page) {
first, which is then installing the special vvar page.
It's clear that the code will hit the next fault immediately when trying to
access the real vvar page at the timens offset. So it might be sensible to
map that one in one go to avoid the immediate second page fault. But that
should be a separate patch after the initial 'functional' one.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 24/36] x86/vdso: Switch image on setns()/clone()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, Andrei Vagin
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
It will add a penalty for everybody as branch predictor may mispredict
the jump. Also there are instruction cache lines wasted on cmp/jmp.
Those effects of introducing time namespace are very much unwanted
having in mind how much work have been spent on micro-optimisation
vdso code.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
Whenever a user does setns() or unshare(CLONE_TIMENS) followed
by clone(), change VDSO image in mm and zap VVAR/VDSO page tables.
They will be re-faulted with corresponding image and VVAR offsets.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vma.c | 23 +++++++++++++++++++++++
arch/x86/include/asm/vdso.h | 1 +
kernel/time_namespace.c | 11 +++++++++++
3 files changed, 35 insertions(+)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 8a8211fd4cfc..91cf5a5c8c9e 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -25,6 +25,7 @@
#include <asm/cpufeature.h>
#include <clocksource/hyperv_timer.h>
#include <asm/page.h>
+#include <asm/tlb.h>
#if defined(CONFIG_X86_64)
unsigned int __read_mostly vdso64_enabled = 1;
@@ -266,6 +267,28 @@ static const struct vm_special_mapping vvar_mapping = {
.mremap = vvar_mremap,
};
+#ifdef CONFIG_TIME_NS
+int vdso_join_timens(struct task_struct *task)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma;
+
+ if (down_write_killable(&mm->mmap_sem))
+ return -EINTR;
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ unsigned long size = vma->vm_end - vma->vm_start;
+
+ if (vma_is_special_mapping(vma, &vvar_mapping) ||
+ vma_is_special_mapping(vma, &vdso_mapping))
+ zap_page_range(vma, vma->vm_start, size);
+ }
+
+ up_write(&mm->mmap_sem);
+ return 0;
+}
+#endif
+
/*
* Add vdso and vvar mappings to current process.
* @image - blob to map
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index 03f468c63a24..ccf89dedd04f 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -45,6 +45,7 @@ extern struct vdso_image vdso_image_32;
extern void __init init_vdso_image(struct vdso_image *image);
extern int map_vdso_once(const struct vdso_image *image, unsigned long addr);
+extern int vdso_join_timens(struct task_struct *task);
#endif /* __ASSEMBLER__ */
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index ff2c5de7e815..a01c25fe76d5 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -15,6 +15,7 @@
#include <linux/cred.h>
#include <linux/err.h>
#include <linux/mm.h>
+#include <asm/vdso.h>
ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
struct timens_offsets *ns_offsets)
@@ -201,6 +202,7 @@ static void timens_put(struct ns_common *ns)
static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
{
struct time_namespace *ns = to_time_ns(new);
+ int ret;
if (!current_is_single_threaded())
return -EUSERS;
@@ -209,6 +211,10 @@ static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
!ns_capable(current_user_ns(), CAP_SYS_ADMIN))
return -EPERM;
+ ret = vdso_join_timens(current);
+ if (ret)
+ return ret;
+
get_time_ns(ns);
get_time_ns(ns);
put_time_ns(nsproxy->time_ns);
@@ -223,10 +229,15 @@ int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
{
struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
struct time_namespace *ns = to_time_ns(nsc);
+ int ret;
if (nsproxy->time_ns == nsproxy->time_ns_for_children)
return 0;
+ ret = vdso_join_timens(tsk);
+ if (ret)
+ return ret;
+
get_time_ns(ns);
put_time_ns(nsproxy->time_ns);
nsproxy->time_ns = ns;
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 24/36] x86/vdso: Switch image on setns()/clone()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
It will add a penalty for everybody as branch predictor may mispredict
the jump. Also there are instruction cache lines wasted on cmp/jmp.
Those effects of introducing time namespace are very much unwanted
having in mind how much work have been spent on micro-optimisation
vdso code.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
Whenever a user does setns() or unshare(CLONE_TIMENS) followed
by clone(), change VDSO image in mm and zap VVAR/VDSO page tables.
They will be re-faulted with corresponding image and VVAR offsets.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vma.c | 23 +++++++++++++++++++++++
arch/x86/include/asm/vdso.h | 1 +
kernel/time_namespace.c | 11 +++++++++++
3 files changed, 35 insertions(+)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 8a8211fd4cfc..91cf5a5c8c9e 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -25,6 +25,7 @@
#include <asm/cpufeature.h>
#include <clocksource/hyperv_timer.h>
#include <asm/page.h>
+#include <asm/tlb.h>
#if defined(CONFIG_X86_64)
unsigned int __read_mostly vdso64_enabled = 1;
@@ -266,6 +267,28 @@ static const struct vm_special_mapping vvar_mapping = {
.mremap = vvar_mremap,
};
+#ifdef CONFIG_TIME_NS
+int vdso_join_timens(struct task_struct *task)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma;
+
+ if (down_write_killable(&mm->mmap_sem))
+ return -EINTR;
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ unsigned long size = vma->vm_end - vma->vm_start;
+
+ if (vma_is_special_mapping(vma, &vvar_mapping) ||
+ vma_is_special_mapping(vma, &vdso_mapping))
+ zap_page_range(vma, vma->vm_start, size);
+ }
+
+ up_write(&mm->mmap_sem);
+ return 0;
+}
+#endif
+
/*
* Add vdso and vvar mappings to current process.
* @image - blob to map
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index 03f468c63a24..ccf89dedd04f 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -45,6 +45,7 @@ extern struct vdso_image vdso_image_32;
extern void __init init_vdso_image(struct vdso_image *image);
extern int map_vdso_once(const struct vdso_image *image, unsigned long addr);
+extern int vdso_join_timens(struct task_struct *task);
#endif /* __ASSEMBLER__ */
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index ff2c5de7e815..a01c25fe76d5 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -15,6 +15,7 @@
#include <linux/cred.h>
#include <linux/err.h>
#include <linux/mm.h>
+#include <asm/vdso.h>
ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim,
struct timens_offsets *ns_offsets)
@@ -201,6 +202,7 @@ static void timens_put(struct ns_common *ns)
static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
{
struct time_namespace *ns = to_time_ns(new);
+ int ret;
if (!current_is_single_threaded())
return -EUSERS;
@@ -209,6 +211,10 @@ static int timens_install(struct nsproxy *nsproxy, struct ns_common *new)
!ns_capable(current_user_ns(), CAP_SYS_ADMIN))
return -EPERM;
+ ret = vdso_join_timens(current);
+ if (ret)
+ return ret;
+
get_time_ns(ns);
get_time_ns(ns);
put_time_ns(nsproxy->time_ns);
@@ -223,10 +229,15 @@ int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
{
struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
struct time_namespace *ns = to_time_ns(nsc);
+ int ret;
if (nsproxy->time_ns == nsproxy->time_ns_for_children)
return 0;
+ ret = vdso_join_timens(tsk);
+ if (ret)
+ return ret;
+
get_time_ns(ns);
put_time_ns(nsproxy->time_ns);
nsproxy->time_ns = ns;
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 25/36] vdso: Introduce vdso_static_branch_unlikely()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
Introduce vdso_static_branch_unlikely(), which is similar to
static_branch_unlikely(); alias it with timens_static_branch_unlikely()
under CONFIG_TIME_NS.
The timens code in vdso will look like this:
if (timens_static_branch_unlikely()) {
clk_to_ns(clk, ts);
}
The version of vdso which is compiled from sources will never execute
clk_to_ns(). And then we can patch the 'no-op' in the straight-line
codepath with a 'jump' instruction to the out-of-line true branch and
get the timens version of the vdso library.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/include/asm/jump_label.h | 14 ++++++++++++++
lib/vdso/gettimeofday.c | 10 ++++++++--
2 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
index 06c3cc22a058..376efb53183b 100644
--- a/arch/x86/include/asm/jump_label.h
+++ b/arch/x86/include/asm/jump_label.h
@@ -53,6 +53,20 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool
return true;
}
+static __always_inline bool vdso_static_branch_unlikely(void)
+{
+ asm_volatile_goto("1:\n\t"
+ ".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t"
+ ".pushsection __jump_table, \"aw\"\n\t"
+ "2: .word 1b - 2b, %l[l_yes] - 2b\n\t"
+ ".popsection\n\t"
+ : : : : l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
#else /* __ASSEMBLY__ */
.macro STATIC_JUMP_IF_TRUE target, key, def
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index 8589c66ff3e7..7df8fa6c03fa 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -8,6 +8,7 @@
#include <linux/kernel.h>
#include <linux/hrtimer_defs.h>
#include <linux/timens_offsets.h>
+#include <linux/jump_label.h>
#include <vdso/datapage.h>
#include <vdso/helpers.h>
@@ -43,6 +44,8 @@ u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
extern u8 timens_page
__attribute__((visibility("hidden")));
+#define timens_static_branch_unlikely vdso_static_branch_unlikely
+
notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts)
{
struct timens_offsets *timens = (struct timens_offsets *) &timens_page;
@@ -79,6 +82,7 @@ notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_tim
}
#else
notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts) {}
+notrace static __always_inline bool timens_static_branch_unlikely(void) { return false; }
#endif
static int do_hres(const struct vdso_data *vd, clockid_t clk,
@@ -108,7 +112,8 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk,
ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
ts->tv_nsec = ns;
- clk_to_ns(clk, ts);
+ if (timens_static_branch_unlikely())
+ clk_to_ns(clk, ts);
return 0;
}
@@ -125,7 +130,8 @@ static void do_coarse(const struct vdso_data *vd, clockid_t clk,
ts->tv_nsec = vdso_ts->nsec;
} while (unlikely(vdso_read_retry(vd, seq)));
- clk_to_ns(clk, ts);
+ if (timens_static_branch_unlikely())
+ clk_to_ns(clk, ts);
}
static __maybe_unused int
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 25/36] vdso: Introduce vdso_static_branch_unlikely()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
Introduce vdso_static_branch_unlikely(), which is similar to
static_branch_unlikely(); alias it with timens_static_branch_unlikely()
under CONFIG_TIME_NS.
The timens code in vdso will look like this:
if (timens_static_branch_unlikely()) {
clk_to_ns(clk, ts);
}
The version of vdso which is compiled from sources will never execute
clk_to_ns(). And then we can patch the 'no-op' in the straight-line
codepath with a 'jump' instruction to the out-of-line true branch and
get the timens version of the vdso library.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/include/asm/jump_label.h | 14 ++++++++++++++
lib/vdso/gettimeofday.c | 10 ++++++++--
2 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
index 06c3cc22a058..376efb53183b 100644
--- a/arch/x86/include/asm/jump_label.h
+++ b/arch/x86/include/asm/jump_label.h
@@ -53,6 +53,20 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool
return true;
}
+static __always_inline bool vdso_static_branch_unlikely(void)
+{
+ asm_volatile_goto("1:\n\t"
+ ".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t"
+ ".pushsection __jump_table, \"aw\"\n\t"
+ "2: .word 1b - 2b, %l[l_yes] - 2b\n\t"
+ ".popsection\n\t"
+ : : : : l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
#else /* __ASSEMBLY__ */
.macro STATIC_JUMP_IF_TRUE target, key, def
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index 8589c66ff3e7..7df8fa6c03fa 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -8,6 +8,7 @@
#include <linux/kernel.h>
#include <linux/hrtimer_defs.h>
#include <linux/timens_offsets.h>
+#include <linux/jump_label.h>
#include <vdso/datapage.h>
#include <vdso/helpers.h>
@@ -43,6 +44,8 @@ u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
extern u8 timens_page
__attribute__((visibility("hidden")));
+#define timens_static_branch_unlikely vdso_static_branch_unlikely
+
notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts)
{
struct timens_offsets *timens = (struct timens_offsets *) &timens_page;
@@ -79,6 +82,7 @@ notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_tim
}
#else
notrace static __always_inline void clk_to_ns(clockid_t clk, struct __kernel_timespec *ts) {}
+notrace static __always_inline bool timens_static_branch_unlikely(void) { return false; }
#endif
static int do_hres(const struct vdso_data *vd, clockid_t clk,
@@ -108,7 +112,8 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk,
ts->tv_sec = sec + __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
ts->tv_nsec = ns;
- clk_to_ns(clk, ts);
+ if (timens_static_branch_unlikely())
+ clk_to_ns(clk, ts);
return 0;
}
@@ -125,7 +130,8 @@ static void do_coarse(const struct vdso_data *vd, clockid_t clk,
ts->tv_nsec = vdso_ts->nsec;
} while (unlikely(vdso_read_retry(vd, seq)));
- clk_to_ns(clk, ts);
+ if (timens_static_branch_unlikely())
+ clk_to_ns(clk, ts);
}
static __maybe_unused int
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 25/36] vdso: Introduce vdso_static_branch_unlikely()
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 18:03 ` Thomas Gleixner
-1 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 18:03 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Andrei Vagin, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> From: Andrei Vagin <avagin@gmail.com>
>
> As it has been discussed on timens RFC, adding a new conditional branch
> `if (inside_time_ns)` on VDSO for all processes is undesirable.
>
> Addressing those problems, there are two versions of VDSO's .so:
> for host tasks (without any penalty) and for processes inside of time
> namespace with clk_to_ns() that subtracts offsets from host's time.
>
> Introduce vdso_static_branch_unlikely(), which is similar to
> static_branch_unlikely(); alias it with timens_static_branch_unlikely()
> under CONFIG_TIME_NS.
>
> The timens code in vdso will look like this:
>
> if (timens_static_branch_unlikely()) {
> clk_to_ns(clk, ts);
Please name that clk_to_namespace(). _ns() is widely used for nanoseconds.
> }
>
> The version of vdso which is compiled from sources will never execute
> clk_to_ns(). And then we can patch the 'no-op' in the straight-line
> codepath with a 'jump' instruction to the out-of-line true branch and
> get the timens version of the vdso library.
Colour me confused. Why do we need that static branch at all?
Why don't we compile VDSO_NO_NAMESPACE and VDSO_NAMESPACE right away? One
has the clk_to_namespace() one does not. The you can spare the whole static
key patching and the NO_NAMESPACE variant does not have extra 5 NOPS.
The VDSO is one page IIRC, so having the extra namespace variant around
does really not matter at all.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 26/36] x86/vdso2c: Process jump tables
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, Andrei Vagin
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside time
namespace with clk_to_ns() that subtracts offsets from host's time.
The timens code in vdso looks like this:
if (timens_static_branch()) {
clk_to_ns(clk, ts);
}
Static branch mechanism adds a __jump_table section into vdso.
Vdso's linker script drops all unwanted sections in compile time.
Preserve __jump_table section and add it into (struct vdso_image),
as it's needed for enabling (patching) static branches that are
present on vdso.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vdso-layout.lds.S | 1 +
arch/x86/entry/vdso/vdso2c.h | 9 ++++++++-
arch/x86/include/asm/vdso.h | 1 +
3 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index ba216527e59f..69dbe4821aa5 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -45,6 +45,7 @@ SECTIONS
.gnu.version : { *(.gnu.version) }
.gnu.version_d : { *(.gnu.version_d) }
.gnu.version_r : { *(.gnu.version_r) }
+ __jump_table : { *(__jump_table) } :text
.dynamic : { *(.dynamic) } :text :dynamic
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index 885b988aea19..318b278ca396 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -14,7 +14,7 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
unsigned long mapping_size;
ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
unsigned int i, syms_nr;
- unsigned long j;
+ unsigned long j, jump_table_addr = -1UL, jump_table_size = -1UL;
ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
*alt_sec = NULL;
ELF(Dyn) *dyn = 0, *dyn_end = 0;
@@ -78,6 +78,10 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
if (!strcmp(secstrings + GET_LE(&sh->sh_name),
".altinstructions"))
alt_sec = sh;
+ if (!strcmp(secstrings + GET_LE(&sh->sh_name), "__jump_table")) {
+ jump_table_addr = GET_LE(&sh->sh_offset);
+ jump_table_size = GET_LE(&sh->sh_size);
+ }
}
if (!symtab_hdr)
@@ -166,6 +170,9 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
fprintf(outfile, "\t.alt_len = %lu,\n",
(unsigned long)GET_LE(&alt_sec->sh_size));
}
+ fprintf(outfile, "\t.jump_table = %luUL,\n", jump_table_addr);
+ fprintf(outfile, "\t.jump_table_len = %luUL,\n", jump_table_size);
+
for (i = 0; i < NSYMS; i++) {
if (required_syms[i].export && syms[i])
fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n",
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index ccf89dedd04f..5e83bd3cda22 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -16,6 +16,7 @@ struct vdso_image {
unsigned long size; /* Always a multiple of PAGE_SIZE */
unsigned long alt, alt_len;
+ unsigned long jump_table, jump_table_len;
long sym_vvar_start; /* Negative offset to the vvar area */
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 26/36] x86/vdso2c: Process jump tables
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside time
namespace with clk_to_ns() that subtracts offsets from host's time.
The timens code in vdso looks like this:
if (timens_static_branch()) {
clk_to_ns(clk, ts);
}
Static branch mechanism adds a __jump_table section into vdso.
Vdso's linker script drops all unwanted sections in compile time.
Preserve __jump_table section and add it into (struct vdso_image),
as it's needed for enabling (patching) static branches that are
present on vdso.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vdso-layout.lds.S | 1 +
arch/x86/entry/vdso/vdso2c.h | 9 ++++++++-
arch/x86/include/asm/vdso.h | 1 +
3 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index ba216527e59f..69dbe4821aa5 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -45,6 +45,7 @@ SECTIONS
.gnu.version : { *(.gnu.version) }
.gnu.version_d : { *(.gnu.version_d) }
.gnu.version_r : { *(.gnu.version_r) }
+ __jump_table : { *(__jump_table) } :text
.dynamic : { *(.dynamic) } :text :dynamic
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index 885b988aea19..318b278ca396 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -14,7 +14,7 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
unsigned long mapping_size;
ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
unsigned int i, syms_nr;
- unsigned long j;
+ unsigned long j, jump_table_addr = -1UL, jump_table_size = -1UL;
ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
*alt_sec = NULL;
ELF(Dyn) *dyn = 0, *dyn_end = 0;
@@ -78,6 +78,10 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
if (!strcmp(secstrings + GET_LE(&sh->sh_name),
".altinstructions"))
alt_sec = sh;
+ if (!strcmp(secstrings + GET_LE(&sh->sh_name), "__jump_table")) {
+ jump_table_addr = GET_LE(&sh->sh_offset);
+ jump_table_size = GET_LE(&sh->sh_size);
+ }
}
if (!symtab_hdr)
@@ -166,6 +170,9 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
fprintf(outfile, "\t.alt_len = %lu,\n",
(unsigned long)GET_LE(&alt_sec->sh_size));
}
+ fprintf(outfile, "\t.jump_table = %luUL,\n", jump_table_addr);
+ fprintf(outfile, "\t.jump_table_len = %luUL,\n", jump_table_size);
+
for (i = 0; i < NSYMS; i++) {
if (required_syms[i].export && syms[i])
fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n",
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index ccf89dedd04f..5e83bd3cda22 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -16,6 +16,7 @@ struct vdso_image {
unsigned long size; /* Always a multiple of PAGE_SIZE */
unsigned long alt, alt_len;
+ unsigned long jump_table, jump_table_len;
long sym_vvar_start; /* Negative offset to the vvar area */
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 27/36] x86/vdso: Enable static branches for the timens vdso
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
The timens code in vdso looks like this:
if (timens_static_branch_unlikely()) {
clk_to_ns(clk, ts);
}
This static branch is disabled by default. And the code generated consist
of a single atomic 'no-op' instruction, in the straight-line code path.
Enable static branches in the timens vdso: the 'no-op' instruction
gets replaced with a 'jump' instruction to the out-of-line true branch.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vma.c | 30 ++++++++++++++++++++++++------
arch/x86/kernel/jump_label.c | 14 ++++++++++++++
include/linux/jump_label.h | 8 ++++++++
init/Kconfig | 1 +
4 files changed, 47 insertions(+), 6 deletions(-)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 91cf5a5c8c9e..1a3eb4656eb6 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -15,6 +15,7 @@
#include <linux/cpu.h>
#include <linux/ptrace.h>
#include <linux/time_namespace.h>
+#include <linux/jump_label.h>
#include <asm/pvclock.h>
#include <asm/vgtod.h>
#include <asm/proto.h>
@@ -31,20 +32,37 @@
unsigned int __read_mostly vdso64_enabled = 1;
#endif
-void __init init_vdso_image(struct vdso_image *image)
+#ifdef CONFIG_TIME_NS
+static __init void init_timens(struct vdso_image *image)
{
- BUG_ON(image->size % PAGE_SIZE != 0);
+ struct vdso_jump_entry *entries;
+ unsigned long entries_nr;
+
+ if (WARN_ON(image->jump_table == -1UL))
+ return;
- apply_alternatives((struct alt_instr *)(image->text + image->alt),
- (struct alt_instr *)(image->text + image->alt +
- image->alt_len));
-#ifdef CONFIG_TIME_NS
image->text_timens = vmalloc_32(image->size);
if (WARN_ON(image->text_timens == NULL))
return;
memcpy(image->text_timens, image->text, image->size);
+
+ entries = image->text_timens + image->jump_table;
+ entries_nr = image->jump_table_len / sizeof(struct vdso_jump_entry);
+ apply_vdso_jump_labels(entries, entries_nr);
+}
+#else
+static inline void init_timens(struct vdso_image *image) {}
#endif
+
+void __init init_vdso_image(struct vdso_image *image)
+{
+ BUG_ON(image->size % PAGE_SIZE != 0);
+
+ apply_alternatives((struct alt_instr *)(image->text + image->alt),
+ (struct alt_instr *)(image->text + image->alt +
+ image->alt_len));
+ init_timens(image);
}
struct linux_binprm;
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index 044053235302..7820ac61b688 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -24,6 +24,20 @@ union jump_code_union {
} __attribute__((packed));
};
+__init void apply_vdso_jump_labels(struct vdso_jump_entry *ent, unsigned long nr)
+{
+ while (nr--) {
+ void *code_addr = (void *)ent + ent->code;
+ union jump_code_union jmp;
+
+ jmp.jump = 0xe9; /* JMP rel32 */
+ jmp.offset = ent->target - ent->code - JUMP_LABEL_NOP_SIZE;
+ memcpy(code_addr, &jmp, JUMP_LABEL_NOP_SIZE);
+
+ ent++;
+ }
+}
+
static void bug_at(unsigned char *ip, int line)
{
/*
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index 3526c0aee954..bb9d828ee49a 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -125,6 +125,11 @@ struct jump_entry {
long key; // key may be far away from the core kernel under KASLR
};
+struct vdso_jump_entry {
+ u16 code;
+ u16 target;
+};
+
static inline unsigned long jump_entry_code(const struct jump_entry *entry)
{
return (unsigned long)&entry->code + entry->code;
@@ -229,6 +234,9 @@ extern void static_key_enable(struct static_key *key);
extern void static_key_disable(struct static_key *key);
extern void static_key_enable_cpuslocked(struct static_key *key);
extern void static_key_disable_cpuslocked(struct static_key *key);
+extern void apply_vdso_jump_labels(struct vdso_jump_entry *ent,
+ unsigned long nr);
+
/*
* We should be using ATOMIC_INIT() for initializing .enabled, but
diff --git a/init/Kconfig b/init/Kconfig
index 7adf939eeaa8..7d2bad36a1be 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1075,6 +1075,7 @@ config UTS_NS
config TIME_NS
bool "TIME namespace"
depends on ARCH_HAS_VDSO_TIME_NS
+ depends on JUMP_LABEL
default y
help
In this namespace boottime and monotonic clocks can be set.
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 27/36] x86/vdso: Enable static branches for the timens vdso
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
As it has been discussed on timens RFC, adding a new conditional branch
`if (inside_time_ns)` on VDSO for all processes is undesirable.
Addressing those problems, there are two versions of VDSO's .so:
for host tasks (without any penalty) and for processes inside of time
namespace with clk_to_ns() that subtracts offsets from host's time.
The timens code in vdso looks like this:
if (timens_static_branch_unlikely()) {
clk_to_ns(clk, ts);
}
This static branch is disabled by default. And the code generated consist
of a single atomic 'no-op' instruction, in the straight-line code path.
Enable static branches in the timens vdso: the 'no-op' instruction
gets replaced with a 'jump' instruction to the out-of-line true branch.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/x86/entry/vdso/vma.c | 30 ++++++++++++++++++++++++------
arch/x86/kernel/jump_label.c | 14 ++++++++++++++
include/linux/jump_label.h | 8 ++++++++
init/Kconfig | 1 +
4 files changed, 47 insertions(+), 6 deletions(-)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 91cf5a5c8c9e..1a3eb4656eb6 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -15,6 +15,7 @@
#include <linux/cpu.h>
#include <linux/ptrace.h>
#include <linux/time_namespace.h>
+#include <linux/jump_label.h>
#include <asm/pvclock.h>
#include <asm/vgtod.h>
#include <asm/proto.h>
@@ -31,20 +32,37 @@
unsigned int __read_mostly vdso64_enabled = 1;
#endif
-void __init init_vdso_image(struct vdso_image *image)
+#ifdef CONFIG_TIME_NS
+static __init void init_timens(struct vdso_image *image)
{
- BUG_ON(image->size % PAGE_SIZE != 0);
+ struct vdso_jump_entry *entries;
+ unsigned long entries_nr;
+
+ if (WARN_ON(image->jump_table == -1UL))
+ return;
- apply_alternatives((struct alt_instr *)(image->text + image->alt),
- (struct alt_instr *)(image->text + image->alt +
- image->alt_len));
-#ifdef CONFIG_TIME_NS
image->text_timens = vmalloc_32(image->size);
if (WARN_ON(image->text_timens == NULL))
return;
memcpy(image->text_timens, image->text, image->size);
+
+ entries = image->text_timens + image->jump_table;
+ entries_nr = image->jump_table_len / sizeof(struct vdso_jump_entry);
+ apply_vdso_jump_labels(entries, entries_nr);
+}
+#else
+static inline void init_timens(struct vdso_image *image) {}
#endif
+
+void __init init_vdso_image(struct vdso_image *image)
+{
+ BUG_ON(image->size % PAGE_SIZE != 0);
+
+ apply_alternatives((struct alt_instr *)(image->text + image->alt),
+ (struct alt_instr *)(image->text + image->alt +
+ image->alt_len));
+ init_timens(image);
}
struct linux_binprm;
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index 044053235302..7820ac61b688 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -24,6 +24,20 @@ union jump_code_union {
} __attribute__((packed));
};
+__init void apply_vdso_jump_labels(struct vdso_jump_entry *ent, unsigned long nr)
+{
+ while (nr--) {
+ void *code_addr = (void *)ent + ent->code;
+ union jump_code_union jmp;
+
+ jmp.jump = 0xe9; /* JMP rel32 */
+ jmp.offset = ent->target - ent->code - JUMP_LABEL_NOP_SIZE;
+ memcpy(code_addr, &jmp, JUMP_LABEL_NOP_SIZE);
+
+ ent++;
+ }
+}
+
static void bug_at(unsigned char *ip, int line)
{
/*
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index 3526c0aee954..bb9d828ee49a 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -125,6 +125,11 @@ struct jump_entry {
long key; // key may be far away from the core kernel under KASLR
};
+struct vdso_jump_entry {
+ u16 code;
+ u16 target;
+};
+
static inline unsigned long jump_entry_code(const struct jump_entry *entry)
{
return (unsigned long)&entry->code + entry->code;
@@ -229,6 +234,9 @@ extern void static_key_enable(struct static_key *key);
extern void static_key_disable(struct static_key *key);
extern void static_key_enable_cpuslocked(struct static_key *key);
extern void static_key_disable_cpuslocked(struct static_key *key);
+extern void apply_vdso_jump_labels(struct vdso_jump_entry *ent,
+ unsigned long nr);
+
/*
* We should be using ATOMIC_INIT() for initializing .enabled, but
diff --git a/init/Kconfig b/init/Kconfig
index 7adf939eeaa8..7d2bad36a1be 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1075,6 +1075,7 @@ config UTS_NS
config TIME_NS
bool "TIME namespace"
depends on ARCH_HAS_VDSO_TIME_NS
+ depends on JUMP_LABEL
default y
help
In this namespace boottime and monotonic clocks can be set.
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 28/36] posix-clocks: Add align for timens_offsets
2019-08-15 16:38 ` Dmitry Safonov
` (27 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
2019-08-15 19:22 ` Thomas Gleixner
-1 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
Align offsets so that time namespace will work for ia32 applications on
x86_64 host.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
include/linux/timens_offsets.h | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/include/linux/timens_offsets.h b/include/linux/timens_offsets.h
index e93aabaa5e45..05da1b0563ce 100644
--- a/include/linux/timens_offsets.h
+++ b/include/linux/timens_offsets.h
@@ -2,9 +2,17 @@
#ifndef _LINUX_TIME_OFFSETS_H
#define _LINUX_TIME_OFFSETS_H
+/*
+ * Time offsets need align as they're placed on VVAR page,
+ * which is used by x86_64 and ia32 VDSO code.
+ * On ia32 offset::tv_sec (u64) has align(4), so re-align offsets
+ * to the same positions as 64-bit offsets.
+ * On 64-bit big-endian systems VDSO should convert to timespec64
+ * to timespec because of a padding occurring between the fields.
+ */
struct timens_offsets {
- struct timespec64 monotonic;
- struct timespec64 boottime;
+ struct timespec64 monotonic __aligned(8);
+ struct timespec64 boottime __aligned(8);
};
#endif
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 28/36] posix-clocks: Add align for timens_offsets
2019-08-15 16:38 ` [PATCHv6 28/36] posix-clocks: Add align for timens_offsets Dmitry Safonov
@ 2019-08-15 19:22 ` Thomas Gleixner
2019-08-16 6:36 ` Thomas Gleixner
0 siblings, 1 reply; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-15 19:22 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Dmitry Safonov wrote:
> Align offsets so that time namespace will work for ia32 applications on
> x86_64 host.
That's true for any 64 bit arch which supports 32bit user space and should
be folded into the patch which introduces the offset store.
> +/*
> + * Time offsets need align as they're placed on VVAR page,
> + * which is used by x86_64 and ia32 VDSO code.
> + * On ia32 offset::tv_sec (u64) has align(4), so re-align offsets
> + * to the same positions as 64-bit offsets.
This is generic code. Please do not add x86'isms here. The alignement
problem is more or less the same for any 64bit arch which supports 32bit
user space. And it's even worse on BE.
> + * On 64-bit big-endian systems VDSO should convert to timespec64
> + * to timespec ...
What?
> ... because of a padding occurring between the fields.
There is no padding between the fields.
32bit BE (powerpc)
struct timespec64 {
time64_t tv_sec; /* 0 8 */
long int tv_nsec; /* 8 4 */
tv_nsec is directly after tv_sec
};
64bit LE and BE (x86, powerpc64)
struct timespec64 {
time64_t tv_sec; /* 0 8 */
long int tv_nsec; /* 8 8 */
};
The problem for BE is that the 64bit host uses long int to store
tv_nsec. So the 32bit userspace will always read 0 because it reads byte
2/3 as seen from the 64 host side.
So using struct timespec64 for the offset is wrong. You really need to open
code that offset storage if you don't want to end up with weird workarounds
for BE.
Something like this:
struct timens_offs {
time64_t tv_sec;
s64 tv_nsec;
};
Then your offset store becomes:
struct timens_offsets {
struct timens_offs monotonic;
struct timens_offs boottime;
};
which needs tweaks to your conversion functions:
static inline void timens_add_monotonic(struct timespec64 *ts)
{
struct timens_offsets *ns_offsets = current->nsproxy->time_ns->offsets;
struct timens_offs *mo = &ns_offsets->monotonic;
if (ns_offsets) {
set_normalized_timespec64(ts, ts->tv_sec + mo->tv_sec,
ts->tv_nsec + mo->tv_nsec);
}
}
And for your to host conversion you need:
case CLOCK_MONOTONIC:
mo = &ns_offsets->monotonic;
offset = ktime_set(mo->tv_sec, mo->tv_nsec);
break;
Similar changes are needed in the VDSO and the proc interface
obviously. Then this works for any arch without magic BE fixups. You get
the idea.
And ideally you change that storage to:
struct timens_offs {
time64_t tv_sec;
s64 tv_nsec;
ktime_t nsecs;
};
and do the conversion once in the proc write. Then your to host conversion
can use 'nsecs' and spare the multiplication on every invocation.
case CLOCK_MONOTONIC:
offset = ns_offsets.monotonic.nsecs;
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread* Re: [PATCHv6 28/36] posix-clocks: Add align for timens_offsets
2019-08-15 19:22 ` Thomas Gleixner
@ 2019-08-16 6:36 ` Thomas Gleixner
0 siblings, 0 replies; 87+ messages in thread
From: Thomas Gleixner @ 2019-08-16 6:36 UTC (permalink / raw)
To: Dmitry Safonov
Cc: linux-kernel, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Vincenzo Frascino, containers, criu, linux-api, x86
On Thu, 15 Aug 2019, Thomas Gleixner wrote:
> So using struct timespec64 for the offset is wrong. You really need to open
> code that offset storage if you don't want to end up with weird workarounds
> for BE.
>
> Something like this:
>
> struct timens_offs {
> time64_t tv_sec;
> s64 tv_nsec;
Actually that should use 'int' for the tv_nsec part.
Thanks,
tglx
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 29/36] fs/proc: Introduce /proc/pid/timens_offsets
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
API to set time namespace offsets for children processes, i.e.:
echo "clockid off_ses off_nsec" > /proc/self/timens_offsets
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
fs/proc/base.c | 95 ++++++++++++++++++++++++++++++
include/linux/time_namespace.h | 10 ++++
kernel/time_namespace.c | 104 +++++++++++++++++++++++++++++++++
3 files changed, 209 insertions(+)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index ebea9501afb8..1d2007365e87 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -94,6 +94,7 @@
#include <linux/sched/debug.h>
#include <linux/sched/stat.h>
#include <linux/posix-timers.h>
+#include <linux/time_namespace.h>
#include <trace/events/oom.h>
#include "internal.h"
#include "fd.h"
@@ -1533,6 +1534,97 @@ static const struct file_operations proc_pid_sched_autogroup_operations = {
#endif /* CONFIG_SCHED_AUTOGROUP */
+#ifdef CONFIG_TIME_NS
+static int timens_offsets_show(struct seq_file *m, void *v)
+{
+ struct task_struct *p;
+
+ p = get_proc_task(file_inode(m->file));
+ if (!p)
+ return -ESRCH;
+ proc_timens_show_offsets(p, m);
+
+ put_task_struct(p);
+
+ return 0;
+}
+
+static ssize_t
+timens_offsets_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct inode *inode = file_inode(file);
+ struct proc_timens_offset offsets[2];
+ char *kbuf = NULL, *pos, *next_line;
+ struct task_struct *p;
+ int ret, noffsets;
+
+ /* Only allow < page size writes at the beginning of the file */
+ if ((*ppos != 0) || (count >= PAGE_SIZE))
+ return -EINVAL;
+
+ /* Slurp in the user data */
+ kbuf = memdup_user_nul(buf, count);
+ if (IS_ERR(kbuf))
+ return PTR_ERR(kbuf);
+
+ /* Parse the user data */
+ ret = -EINVAL;
+ noffsets = 0;
+ for (pos = kbuf; pos; pos = next_line) {
+ struct proc_timens_offset *off = &offsets[noffsets];
+ int err;
+
+ /* Find the end of line and ensure we don't look past it */
+ next_line = strchr(pos, '\n');
+ if (next_line) {
+ *next_line = '\0';
+ next_line++;
+ if (*next_line == '\0')
+ next_line = NULL;
+ }
+
+ err = sscanf(pos, "%u %lld %lu", &off->clockid,
+ &off->val.tv_sec, &off->val.tv_nsec);
+ if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC)
+ goto out;
+ noffsets++;
+ if (noffsets == ARRAY_SIZE(offsets)) {
+ if (next_line)
+ count = next_line - kbuf;
+ break;
+ }
+ }
+
+ ret = -ESRCH;
+ p = get_proc_task(inode);
+ if (!p)
+ goto out;
+ ret = proc_timens_set_offset(file, p, offsets, noffsets);
+ put_task_struct(p);
+ if (ret)
+ goto out;
+
+ ret = count;
+out:
+ kfree(kbuf);
+ return ret;
+}
+
+static int timens_offsets_open(struct inode *inode, struct file *filp)
+{
+ return single_open(filp, timens_offsets_show, inode);
+}
+
+static const struct file_operations proc_timens_offsets_operations = {
+ .open = timens_offsets_open,
+ .read = seq_read,
+ .write = timens_offsets_write,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+#endif /* CONFIG_TIME_NS */
+
static ssize_t comm_write(struct file *file, const char __user *buf,
size_t count, loff_t *offset)
{
@@ -3015,6 +3107,9 @@ static const struct pid_entry tgid_base_stuff[] = {
#endif
#ifdef CONFIG_SCHED_AUTOGROUP
REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
+#endif
+#ifdef CONFIG_TIME_NS
+ REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations),
#endif
REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 9ba9664ff0ab..3f4d457ff0dc 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -40,6 +40,16 @@ static inline void put_time_ns(struct time_namespace *ns)
kref_put(&ns->kref, free_time_ns);
}
+extern void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m);
+
+struct proc_timens_offset {
+ int clockid;
+ struct timespec64 val;
+};
+
+extern int proc_timens_set_offset(struct file *file, struct task_struct *p,
+ struct proc_timens_offset *offsets, int n);
+
static inline void timens_add_monotonic(struct timespec64 *ts)
{
struct timens_offsets *ns_offsets = current->nsproxy->time_ns->offsets;
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index a01c25fe76d5..1c3ba91873bc 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -8,6 +8,7 @@
#include <linux/user_namespace.h>
#include <linux/sched/signal.h>
#include <linux/sched/task.h>
+#include <linux/seq_file.h>
#include <linux/proc_ns.h>
#include <linux/export.h>
#include <linux/time.h>
@@ -251,6 +252,109 @@ static struct user_namespace *timens_owner(struct ns_common *ns)
return to_time_ns(ns)->user_ns;
}
+static void show_offset(struct seq_file *m, int clockid, struct timespec64 *ts)
+{
+ seq_printf(m, "%d %lld %ld\n", clockid, ts->tv_sec, ts->tv_nsec);
+}
+
+void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m)
+{
+ struct ns_common *ns;
+ struct time_namespace *time_ns;
+ struct timens_offsets *ns_offsets;
+
+ ns = timens_for_children_get(p);
+ if (!ns)
+ return;
+ time_ns = to_time_ns(ns);
+
+ if (!time_ns->offsets) {
+ put_time_ns(time_ns);
+ return;
+ }
+ ns_offsets = time_ns->offsets;
+
+ show_offset(m, CLOCK_MONOTONIC, &ns_offsets->monotonic);
+ show_offset(m, CLOCK_BOOTTIME, &ns_offsets->boottime);
+ put_time_ns(time_ns);
+}
+
+int proc_timens_set_offset(struct file *file, struct task_struct *p,
+ struct proc_timens_offset *offsets, int noffsets)
+{
+ struct ns_common *ns;
+ struct time_namespace *time_ns;
+ struct timens_offsets *ns_offsets;
+ struct timespec64 *offset;
+ struct timespec64 tp;
+ int i, err;
+
+ ns = timens_for_children_get(p);
+ if (!ns)
+ return -ESRCH;
+ time_ns = to_time_ns(ns);
+
+ if (!time_ns->offsets || time_ns->initialized ||
+ !file_ns_capable(file, time_ns->user_ns, CAP_SYS_TIME)) {
+ put_time_ns(time_ns);
+ return -EPERM;
+ }
+ ns_offsets = time_ns->offsets;
+
+ for (i = 0; i < noffsets; i++) {
+ struct proc_timens_offset *off = &offsets[i];
+
+ switch (off->clockid) {
+ case CLOCK_MONOTONIC:
+ ktime_get_ts64(&tp);
+ break;
+ case CLOCK_BOOTTIME:
+ ktime_get_boottime_ts64(&tp);
+ break;
+ default:
+ err = -EINVAL;
+ goto out;
+ }
+
+ err = -ERANGE;
+
+ if (off->val.tv_sec > KTIME_SEC_MAX || off->val.tv_sec < -KTIME_SEC_MAX)
+ goto out;
+
+ tp = timespec64_add(tp, off->val);
+ /*
+ * KTIME_SEC_MAX is divided by 2 to be sure that KTIME_MAX is
+ * still unreachable.
+ */
+ if (tp.tv_sec < 0 || tp.tv_sec > KTIME_SEC_MAX / 2)
+ goto out;
+ }
+
+ err = 0;
+ /* don't report errors after this line */
+ for (i = 0; i < noffsets; i++) {
+ struct proc_timens_offset *off = &offsets[i];
+
+ switch (off->clockid) {
+ case CLOCK_MONOTONIC:
+ offset = &ns_offsets->monotonic;
+ break;
+ case CLOCK_BOOTTIME:
+ offset = &ns_offsets->boottime;
+ break;
+ default:
+ goto out;
+ }
+
+ *offset = off->val;
+ }
+
+out:
+ put_time_ns(time_ns);
+
+ return err;
+}
+
const struct proc_ns_operations timens_operations = {
.name = "time",
.type = CLONE_NEWTIME,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 29/36] fs/proc: Introduce /proc/pid/timens_offsets
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
API to set time namespace offsets for children processes, i.e.:
echo "clockid off_ses off_nsec" > /proc/self/timens_offsets
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
fs/proc/base.c | 95 ++++++++++++++++++++++++++++++
include/linux/time_namespace.h | 10 ++++
kernel/time_namespace.c | 104 +++++++++++++++++++++++++++++++++
3 files changed, 209 insertions(+)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index ebea9501afb8..1d2007365e87 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -94,6 +94,7 @@
#include <linux/sched/debug.h>
#include <linux/sched/stat.h>
#include <linux/posix-timers.h>
+#include <linux/time_namespace.h>
#include <trace/events/oom.h>
#include "internal.h"
#include "fd.h"
@@ -1533,6 +1534,97 @@ static const struct file_operations proc_pid_sched_autogroup_operations = {
#endif /* CONFIG_SCHED_AUTOGROUP */
+#ifdef CONFIG_TIME_NS
+static int timens_offsets_show(struct seq_file *m, void *v)
+{
+ struct task_struct *p;
+
+ p = get_proc_task(file_inode(m->file));
+ if (!p)
+ return -ESRCH;
+ proc_timens_show_offsets(p, m);
+
+ put_task_struct(p);
+
+ return 0;
+}
+
+static ssize_t
+timens_offsets_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct inode *inode = file_inode(file);
+ struct proc_timens_offset offsets[2];
+ char *kbuf = NULL, *pos, *next_line;
+ struct task_struct *p;
+ int ret, noffsets;
+
+ /* Only allow < page size writes at the beginning of the file */
+ if ((*ppos != 0) || (count >= PAGE_SIZE))
+ return -EINVAL;
+
+ /* Slurp in the user data */
+ kbuf = memdup_user_nul(buf, count);
+ if (IS_ERR(kbuf))
+ return PTR_ERR(kbuf);
+
+ /* Parse the user data */
+ ret = -EINVAL;
+ noffsets = 0;
+ for (pos = kbuf; pos; pos = next_line) {
+ struct proc_timens_offset *off = &offsets[noffsets];
+ int err;
+
+ /* Find the end of line and ensure we don't look past it */
+ next_line = strchr(pos, '\n');
+ if (next_line) {
+ *next_line = '\0';
+ next_line++;
+ if (*next_line == '\0')
+ next_line = NULL;
+ }
+
+ err = sscanf(pos, "%u %lld %lu", &off->clockid,
+ &off->val.tv_sec, &off->val.tv_nsec);
+ if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC)
+ goto out;
+ noffsets++;
+ if (noffsets == ARRAY_SIZE(offsets)) {
+ if (next_line)
+ count = next_line - kbuf;
+ break;
+ }
+ }
+
+ ret = -ESRCH;
+ p = get_proc_task(inode);
+ if (!p)
+ goto out;
+ ret = proc_timens_set_offset(file, p, offsets, noffsets);
+ put_task_struct(p);
+ if (ret)
+ goto out;
+
+ ret = count;
+out:
+ kfree(kbuf);
+ return ret;
+}
+
+static int timens_offsets_open(struct inode *inode, struct file *filp)
+{
+ return single_open(filp, timens_offsets_show, inode);
+}
+
+static const struct file_operations proc_timens_offsets_operations = {
+ .open = timens_offsets_open,
+ .read = seq_read,
+ .write = timens_offsets_write,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+#endif /* CONFIG_TIME_NS */
+
static ssize_t comm_write(struct file *file, const char __user *buf,
size_t count, loff_t *offset)
{
@@ -3015,6 +3107,9 @@ static const struct pid_entry tgid_base_stuff[] = {
#endif
#ifdef CONFIG_SCHED_AUTOGROUP
REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
+#endif
+#ifdef CONFIG_TIME_NS
+ REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations),
#endif
REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 9ba9664ff0ab..3f4d457ff0dc 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -40,6 +40,16 @@ static inline void put_time_ns(struct time_namespace *ns)
kref_put(&ns->kref, free_time_ns);
}
+extern void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m);
+
+struct proc_timens_offset {
+ int clockid;
+ struct timespec64 val;
+};
+
+extern int proc_timens_set_offset(struct file *file, struct task_struct *p,
+ struct proc_timens_offset *offsets, int n);
+
static inline void timens_add_monotonic(struct timespec64 *ts)
{
struct timens_offsets *ns_offsets = current->nsproxy->time_ns->offsets;
diff --git a/kernel/time_namespace.c b/kernel/time_namespace.c
index a01c25fe76d5..1c3ba91873bc 100644
--- a/kernel/time_namespace.c
+++ b/kernel/time_namespace.c
@@ -8,6 +8,7 @@
#include <linux/user_namespace.h>
#include <linux/sched/signal.h>
#include <linux/sched/task.h>
+#include <linux/seq_file.h>
#include <linux/proc_ns.h>
#include <linux/export.h>
#include <linux/time.h>
@@ -251,6 +252,109 @@ static struct user_namespace *timens_owner(struct ns_common *ns)
return to_time_ns(ns)->user_ns;
}
+static void show_offset(struct seq_file *m, int clockid, struct timespec64 *ts)
+{
+ seq_printf(m, "%d %lld %ld\n", clockid, ts->tv_sec, ts->tv_nsec);
+}
+
+void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m)
+{
+ struct ns_common *ns;
+ struct time_namespace *time_ns;
+ struct timens_offsets *ns_offsets;
+
+ ns = timens_for_children_get(p);
+ if (!ns)
+ return;
+ time_ns = to_time_ns(ns);
+
+ if (!time_ns->offsets) {
+ put_time_ns(time_ns);
+ return;
+ }
+ ns_offsets = time_ns->offsets;
+
+ show_offset(m, CLOCK_MONOTONIC, &ns_offsets->monotonic);
+ show_offset(m, CLOCK_BOOTTIME, &ns_offsets->boottime);
+ put_time_ns(time_ns);
+}
+
+int proc_timens_set_offset(struct file *file, struct task_struct *p,
+ struct proc_timens_offset *offsets, int noffsets)
+{
+ struct ns_common *ns;
+ struct time_namespace *time_ns;
+ struct timens_offsets *ns_offsets;
+ struct timespec64 *offset;
+ struct timespec64 tp;
+ int i, err;
+
+ ns = timens_for_children_get(p);
+ if (!ns)
+ return -ESRCH;
+ time_ns = to_time_ns(ns);
+
+ if (!time_ns->offsets || time_ns->initialized ||
+ !file_ns_capable(file, time_ns->user_ns, CAP_SYS_TIME)) {
+ put_time_ns(time_ns);
+ return -EPERM;
+ }
+ ns_offsets = time_ns->offsets;
+
+ for (i = 0; i < noffsets; i++) {
+ struct proc_timens_offset *off = &offsets[i];
+
+ switch (off->clockid) {
+ case CLOCK_MONOTONIC:
+ ktime_get_ts64(&tp);
+ break;
+ case CLOCK_BOOTTIME:
+ ktime_get_boottime_ts64(&tp);
+ break;
+ default:
+ err = -EINVAL;
+ goto out;
+ }
+
+ err = -ERANGE;
+
+ if (off->val.tv_sec > KTIME_SEC_MAX || off->val.tv_sec < -KTIME_SEC_MAX)
+ goto out;
+
+ tp = timespec64_add(tp, off->val);
+ /*
+ * KTIME_SEC_MAX is divided by 2 to be sure that KTIME_MAX is
+ * still unreachable.
+ */
+ if (tp.tv_sec < 0 || tp.tv_sec > KTIME_SEC_MAX / 2)
+ goto out;
+ }
+
+ err = 0;
+ /* don't report errors after this line */
+ for (i = 0; i < noffsets; i++) {
+ struct proc_timens_offset *off = &offsets[i];
+
+ switch (off->clockid) {
+ case CLOCK_MONOTONIC:
+ offset = &ns_offsets->monotonic;
+ break;
+ case CLOCK_BOOTTIME:
+ offset = &ns_offsets->boottime;
+ break;
+ default:
+ goto out;
+ }
+
+ *offset = off->val;
+ }
+
+out:
+ put_time_ns(time_ns);
+
+ return err;
+}
+
const struct proc_ns_operations timens_operations = {
.name = "time",
.type = CLONE_NEWTIME,
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 30/36] selftest/timens: Add Time Namespace test for supported clocks
2019-08-15 16:38 ` Dmitry Safonov
` (29 preceding siblings ...)
(?)
@ 2019-08-15 16:38 ` Dmitry Safonov
2019-08-15 23:18 ` shuah
-1 siblings, 1 reply; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
A test to check that all supported clocks work on host and inside
a new time namespace. Use both ways to get time: through VDSO and
by entering the kernel with implicit syscall.
Introduce a new timens directory in selftests framework for
the next timens tests.
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 5 +
tools/testing/selftests/timens/config | 1 +
tools/testing/selftests/timens/log.h | 26 +++
tools/testing/selftests/timens/timens.c | 185 ++++++++++++++++++++++
tools/testing/selftests/timens/timens.h | 63 ++++++++
7 files changed, 282 insertions(+)
create mode 100644 tools/testing/selftests/timens/.gitignore
create mode 100644 tools/testing/selftests/timens/Makefile
create mode 100644 tools/testing/selftests/timens/config
create mode 100644 tools/testing/selftests/timens/log.h
create mode 100644 tools/testing/selftests/timens/timens.c
create mode 100644 tools/testing/selftests/timens/timens.h
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 25b43a8c2b15..6fc63b84a857 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -47,6 +47,7 @@ TARGETS += splice
TARGETS += static_keys
TARGETS += sync
TARGETS += sysctl
+TARGETS += timens
ifneq (1, $(quicktest))
TARGETS += timers
endif
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
new file mode 100644
index 000000000000..27a693229ce1
--- /dev/null
+++ b/tools/testing/selftests/timens/.gitignore
@@ -0,0 +1 @@
+timens
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
new file mode 100644
index 000000000000..b877efb78974
--- /dev/null
+++ b/tools/testing/selftests/timens/Makefile
@@ -0,0 +1,5 @@
+TEST_GEN_PROGS := timens
+
+CFLAGS := -Wall -Werror
+
+include ../lib.mk
diff --git a/tools/testing/selftests/timens/config b/tools/testing/selftests/timens/config
new file mode 100644
index 000000000000..4480620f6f49
--- /dev/null
+++ b/tools/testing/selftests/timens/config
@@ -0,0 +1 @@
+CONFIG_TIME_NS=y
diff --git a/tools/testing/selftests/timens/log.h b/tools/testing/selftests/timens/log.h
new file mode 100644
index 000000000000..db64df2a8483
--- /dev/null
+++ b/tools/testing/selftests/timens/log.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __SELFTEST_TIMENS_LOG_H__
+#define __SELFTEST_TIMENS_LOG_H__
+
+#define pr_msg(fmt, lvl, ...) \
+ ksft_print_msg("[%s] (%s:%d)\t" fmt "\n", \
+ lvl, __FILE__, __LINE__, ##__VA_ARGS__)
+
+#define pr_p(func, fmt, ...) func(fmt ": %m", ##__VA_ARGS__)
+
+#define pr_err(fmt, ...) \
+ ({ \
+ ksft_test_result_error(fmt "\n", ##__VA_ARGS__); \
+ -1; \
+ })
+
+#define pr_fail(fmt, ...) \
+ ({ \
+ ksft_test_result_fail(fmt, ##__VA_ARGS__); \
+ -1; \
+ })
+
+#define pr_perror(fmt, ...) pr_p(pr_err, fmt, ##__VA_ARGS__)
+
+#endif
diff --git a/tools/testing/selftests/timens/timens.c b/tools/testing/selftests/timens/timens.c
new file mode 100644
index 000000000000..55d38f02eb64
--- /dev/null
+++ b/tools/testing/selftests/timens/timens.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+
+#include "log.h"
+#include "timens.h"
+
+/*
+ * Test shouldn't be run for a day, so add 10 days to child
+ * time and check parent's time to be in the same day.
+ */
+#define DAY_IN_SEC (60*60*24)
+#define TEN_DAYS_IN_SEC (10*DAY_IN_SEC)
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+struct test_clock {
+ clockid_t id;
+ char *name;
+ /*
+ * off_id is -1 if a clock has own offset, or it contains an index
+ * which contains a right offset of this clock.
+ */
+ int off_id;
+ time_t offset;
+};
+
+#define ct(clock, off_id) { clock, #clock, off_id }
+static struct test_clock clocks[] = {
+ ct(CLOCK_BOOTTIME, -1),
+ ct(CLOCK_BOOTTIME_ALARM, 1),
+ ct(CLOCK_MONOTONIC, -1),
+ ct(CLOCK_MONOTONIC_COARSE, 1),
+ ct(CLOCK_MONOTONIC_RAW, 1),
+};
+#undef ct
+
+static int child_ns, parent_ns = -1;
+
+static int switch_ns(int fd)
+{
+ if (setns(fd, CLONE_NEWTIME)) {
+ pr_perror("setns()");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int init_namespaces(void)
+{
+ char path[] = "/proc/self/ns/time_for_children";
+ struct stat st1, st2;
+
+ if (parent_ns == -1) {
+ parent_ns = open(path, O_RDONLY);
+ if (parent_ns <= 0)
+ return pr_perror("Unable to open %s", path);
+ }
+
+ if (fstat(parent_ns, &st1))
+ return pr_perror("Unable to stat the parent timens");
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ child_ns = open(path, O_RDONLY);
+ if (child_ns <= 0)
+ return pr_perror("Unable to open %s", path);
+
+ if (fstat(child_ns, &st2))
+ return pr_perror("Unable to stat the timens");
+
+ if (st1.st_ino == st2.st_ino)
+ return pr_perror("The same child_ns after CLONE_NEWTIME");
+
+ return 0;
+}
+
+static int test_gettime(clockid_t clock_index, bool raw_syscall, time_t offset)
+{
+ struct timespec child_ts_new, parent_ts_old, cur_ts;
+ char *entry = raw_syscall ? "syscall" : "vdso";
+ double precision = 0.0;
+
+ switch (clocks[clock_index].id) {
+ case CLOCK_MONOTONIC_COARSE:
+ case CLOCK_MONOTONIC_RAW:
+ precision = -2.0;
+ break;
+ }
+
+ if (switch_ns(parent_ns))
+ return pr_err("switch_ns(%d)", child_ns);
+
+ if (_gettime(clocks[clock_index].id, &parent_ts_old, raw_syscall))
+ return -1;
+
+ child_ts_new.tv_nsec = parent_ts_old.tv_nsec;
+ child_ts_new.tv_sec = parent_ts_old.tv_sec + offset;
+
+ if (switch_ns(child_ns))
+ return pr_err("switch_ns(%d)", child_ns);
+
+ if (_gettime(clocks[clock_index].id, &cur_ts, raw_syscall))
+ return -1;
+
+ if (difftime(cur_ts.tv_sec, child_ts_new.tv_sec) < precision) {
+ ksft_test_result_fail(
+ "Child's %s (%s) time has not changed: %lu -> %lu [%lu]\n",
+ clocks[clock_index].name, entry, parent_ts_old.tv_sec,
+ child_ts_new.tv_sec, cur_ts.tv_sec);
+ return -1;
+ }
+
+ if (switch_ns(parent_ns))
+ return pr_err("switch_ns(%d)", parent_ns);
+
+ if (_gettime(clocks[clock_index].id, &cur_ts, raw_syscall))
+ return -1;
+
+ if (difftime(cur_ts.tv_sec, parent_ts_old.tv_sec) > DAY_IN_SEC) {
+ ksft_test_result_fail(
+ "Parent's %s (%s) time has changed: %lu -> %lu [%lu]\n",
+ clocks[clock_index].name, entry, parent_ts_old.tv_sec,
+ child_ts_new.tv_sec, cur_ts.tv_sec);
+ /* Let's play nice and put it closer to original */
+ clock_settime(clocks[clock_index].id, &cur_ts);
+ return -1;
+ }
+
+ ksft_test_result_pass("Passed for %s (%s)\n",
+ clocks[clock_index].name, entry);
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ unsigned int i;
+ time_t offset;
+ int ret = 0;
+
+ nscheck();
+
+ ksft_set_plan(ARRAY_SIZE(clocks) * 2);
+
+ if (init_namespaces())
+ return 1;
+
+ /* Offsets have to be set before tasks enter the namespace. */
+ for (i = 0; i < ARRAY_SIZE(clocks); i++) {
+ if (clocks[i].off_id != -1)
+ continue;
+ offset = TEN_DAYS_IN_SEC + i * 1000;
+ clocks[i].offset = offset;
+ if (_settime(clocks[i].id, offset))
+ return 1;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(clocks); i++) {
+ if (clocks[i].off_id != -1)
+ offset = clocks[clocks[i].off_id].offset;
+ else
+ offset = clocks[i].offset;
+ ret |= test_gettime(i, true, offset);
+ ret |= test_gettime(i, false, offset);
+ }
+
+ if (ret)
+ ksft_exit_fail();
+
+ ksft_exit_pass();
+ return !!ret;
+}
diff --git a/tools/testing/selftests/timens/timens.h b/tools/testing/selftests/timens/timens.h
new file mode 100644
index 000000000000..77c127384810
--- /dev/null
+++ b/tools/testing/selftests/timens/timens.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __TIMENS_H__
+#define __TIMENS_H__
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+#include "../kselftest.h"
+
+#ifndef CLONE_NEWTIME
+# define CLONE_NEWTIME 0x00000080
+#endif
+
+static inline int _settime(clockid_t clk_id, time_t offset)
+{
+ int fd, len;
+ char buf[4096];
+
+ if (clk_id == CLOCK_MONOTONIC_COARSE || clk_id == CLOCK_MONOTONIC_RAW)
+ clk_id = CLOCK_MONOTONIC;
+
+ len = snprintf(buf, sizeof(buf), "%d %ld 0", clk_id, offset);
+
+ fd = open("/proc/self/timens_offsets", O_WRONLY);
+ if (fd < 0)
+ return pr_perror("/proc/self/timens_offsets");
+
+ if (write(fd, buf, len) != len)
+ return pr_perror("/proc/self/timens_offsets");
+
+ close(fd);
+
+ return 0;
+}
+
+static inline int _gettime(clockid_t clk_id, struct timespec *res, bool raw_syscall)
+{
+ int err;
+
+ if (!raw_syscall) {
+ if (clock_gettime(clk_id, res)) {
+ pr_perror("clock_gettime(%d)", (int)clk_id);
+ return -1;
+ }
+ return 0;
+ }
+
+ err = syscall(SYS_clock_gettime, clk_id, res);
+ if (err)
+ pr_perror("syscall(SYS_clock_gettime(%d))", (int)clk_id);
+
+ return err;
+}
+
+static inline void nscheck(void)
+{
+ if (access("/proc/self/ns/time", F_OK) < 0)
+ ksft_exit_skip("Time namespaces are not supported\n");
+}
+
+#endif
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 30/36] selftest/timens: Add Time Namespace test for supported clocks
2019-08-15 16:38 ` [PATCHv6 30/36] selftest/timens: Add Time Namespace test for supported clocks Dmitry Safonov
@ 2019-08-15 23:18 ` shuah
2019-08-16 6:20 ` Andrei Vagin
0 siblings, 1 reply; 87+ messages in thread
From: shuah @ 2019-08-15 23:18 UTC (permalink / raw)
To: Dmitry Safonov, linux-kernel
Cc: Dmitry Safonov, Adrian Reber, Andrei Vagin, Andy Lutomirski,
Arnd Bergmann, Christian Brauner, Cyrill Gorcunov,
Eric W. Biederman, H. Peter Anvin, Ingo Molnar, Jann Horn,
Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Thomas Gleixner,
Vincenzo Frascino, containers, criu, linux-api, x86, shuah
Hi Dmitry,
Thanks for the patch.
On 8/15/19 10:38 AM, Dmitry Safonov wrote:
> A test to check that all supported clocks work on host and inside
> a new time namespace. Use both ways to get time: through VDSO and
> by entering the kernel with implicit syscall.
>
> Introduce a new timens directory in selftests framework for
> the next timens tests.
>
> Co-developed-by: Andrei Vagin <avagin@openvz.org>
> Signed-off-by: Andrei Vagin <avagin@openvz.org>
> Signed-off-by: Dmitry Safonov <dima@arista.com>
> ---
> tools/testing/selftests/Makefile | 1 +
> tools/testing/selftests/timens/.gitignore | 1 +
> tools/testing/selftests/timens/Makefile | 5 +
> tools/testing/selftests/timens/config | 1 +
> tools/testing/selftests/timens/log.h | 26 +++
> tools/testing/selftests/timens/timens.c | 185 ++++++++++++++++++++++
> tools/testing/selftests/timens/timens.h | 63 ++++++++
> 7 files changed, 282 insertions(+)
> create mode 100644 tools/testing/selftests/timens/.gitignore
> create mode 100644 tools/testing/selftests/timens/Makefile
> create mode 100644 tools/testing/selftests/timens/config
> create mode 100644 tools/testing/selftests/timens/log.h
> create mode 100644 tools/testing/selftests/timens/timens.c
> create mode 100644 tools/testing/selftests/timens/timens.h
>
> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
> index 25b43a8c2b15..6fc63b84a857 100644
> --- a/tools/testing/selftests/Makefile
> +++ b/tools/testing/selftests/Makefile
> @@ -47,6 +47,7 @@ TARGETS += splice
> TARGETS += static_keys
> TARGETS += sync
> TARGETS += sysctl
> +TARGETS += timens
How long does this test run for? Does this test need to be run
as root? If yes, please add a root check and skip the test.
What does the test output looks like for skip and pass/fail cases?
thanks,
-- Shuah
^ permalink raw reply [flat|nested] 87+ messages in thread
* Re: [PATCHv6 30/36] selftest/timens: Add Time Namespace test for supported clocks
2019-08-15 23:18 ` shuah
@ 2019-08-16 6:20 ` Andrei Vagin
0 siblings, 0 replies; 87+ messages in thread
From: Andrei Vagin @ 2019-08-16 6:20 UTC (permalink / raw)
To: shuah
Cc: Dmitry Safonov, linux-kernel, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
On Thu, Aug 15, 2019 at 05:18:21PM -0600, shuah wrote:
> Hi Dmitry,
>
> Thanks for the patch.
>
> On 8/15/19 10:38 AM, Dmitry Safonov wrote:
> > A test to check that all supported clocks work on host and inside
> > a new time namespace. Use both ways to get time: through VDSO and
> > by entering the kernel with implicit syscall.
> >
> > Introduce a new timens directory in selftests framework for
> > the next timens tests.
> >
> > Co-developed-by: Andrei Vagin <avagin@openvz.org>
> > Signed-off-by: Andrei Vagin <avagin@openvz.org>
> > Signed-off-by: Dmitry Safonov <dima@arista.com>
> > ---
> > tools/testing/selftests/Makefile | 1 +
> > tools/testing/selftests/timens/.gitignore | 1 +
> > tools/testing/selftests/timens/Makefile | 5 +
> > tools/testing/selftests/timens/config | 1 +
> > tools/testing/selftests/timens/log.h | 26 +++
> > tools/testing/selftests/timens/timens.c | 185 ++++++++++++++++++++++
> > tools/testing/selftests/timens/timens.h | 63 ++++++++
> > 7 files changed, 282 insertions(+)
> > create mode 100644 tools/testing/selftests/timens/.gitignore
> > create mode 100644 tools/testing/selftests/timens/Makefile
> > create mode 100644 tools/testing/selftests/timens/config
> > create mode 100644 tools/testing/selftests/timens/log.h
> > create mode 100644 tools/testing/selftests/timens/timens.c
> > create mode 100644 tools/testing/selftests/timens/timens.h
> >
> > diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
> > index 25b43a8c2b15..6fc63b84a857 100644
> > --- a/tools/testing/selftests/Makefile
> > +++ b/tools/testing/selftests/Makefile
> > @@ -47,6 +47,7 @@ TARGETS += splice
> > TARGETS += static_keys
> > TARGETS += sync
> > TARGETS += sysctl
> > +TARGETS += timens
>
> How long does this test run for?
On my laptop, it needs 30 miliseconds.
> Does this test need to be run
> as root? If yes, please add a root check and skip the test.
Yes, it needs to be as root. We will add this check. Thanks.
>
> What does the test output looks like for skip and pass/fail cases?
[avagin@laptop timens]$ ./timens
not ok 1 # SKIP Time namespaces are not supported
[root@fc24 timens]# ./timens
1..10
ok 1 Passed for CLOCK_BOOTTIME (syscall)
ok 2 Passed for CLOCK_BOOTTIME (vdso)
ok 3 Passed for CLOCK_BOOTTIME_ALARM (syscall)
ok 4 Passed for CLOCK_BOOTTIME_ALARM (vdso)
ok 5 Passed for CLOCK_MONOTONIC (syscall)
ok 6 Passed for CLOCK_MONOTONIC (vdso)
ok 7 Passed for CLOCK_MONOTONIC_COARSE (syscall)
ok 8 Passed for CLOCK_MONOTONIC_COARSE (vdso)
ok 9 Passed for CLOCK_MONOTONIC_RAW (syscall)
ok 10 Passed for CLOCK_MONOTONIC_RAW (vdso)
# Pass 10 Fail 0 Xfail 0 Xpass 0 Skip 0 Error 0
Thanks,
Andrei
>
> thanks,
> -- Shuah
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 31/36] selftest/timens: Add a test for timerfd
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
Check that timerfd_create() takes into account clock offsets.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/timerfd.c | 129 ++++++++++++++++++++++
3 files changed, 131 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/timerfd.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 27a693229ce1..b609f6ee9fb9 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1 +1,2 @@
timens
+timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index b877efb78974..66b90cd28e5c 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens
+TEST_GEN_PROGS := timens timerfd
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/timens/timerfd.c b/tools/testing/selftests/timens/timerfd.c
new file mode 100644
index 000000000000..b87076aae040
--- /dev/null
+++ b/tools/testing/selftests/timens/timerfd.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+
+#include <sys/timerfd.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+
+#include "log.h"
+#include "timens.h"
+
+static int tclock_gettime(clock_t clockid, struct timespec *now)
+{
+ if (clockid == CLOCK_BOOTTIME_ALARM)
+ clockid = CLOCK_BOOTTIME;
+ return clock_gettime(clockid, now);
+}
+
+int run_test(int clockid, struct timespec now)
+{
+ struct itimerspec new_value;
+ long long elapsed;
+ int fd, i;
+
+ if (tclock_gettime(clockid, &now))
+ return pr_perror("clock_gettime(%d)", clockid);
+
+ for (i = 0; i < 2; i++) {
+ int flags = 0;
+
+ new_value.it_value.tv_sec = 3600;
+ new_value.it_value.tv_nsec = 0;
+ new_value.it_interval.tv_sec = 1;
+ new_value.it_interval.tv_nsec = 0;
+
+ if (i == 1) {
+ new_value.it_value.tv_sec += now.tv_sec;
+ new_value.it_value.tv_nsec += now.tv_nsec;
+ }
+
+ fd = timerfd_create(clockid, 0);
+ if (fd == -1)
+ return pr_perror("timerfd_create(%d)", clockid);
+
+ if (i == 1)
+ flags |= TFD_TIMER_ABSTIME;
+
+ if (timerfd_settime(fd, flags, &new_value, NULL))
+ return pr_perror("timerfd_settime(%d)", clockid);
+
+ if (timerfd_gettime(fd, &new_value))
+ return pr_perror("timerfd_gettime(%d)", clockid);
+
+ elapsed = new_value.it_value.tv_sec;
+ if (abs(elapsed - 3600) > 60) {
+ ksft_test_result_fail("clockid: %d elapsed: %lld\n",
+ clockid, elapsed);
+ return 1;
+ }
+
+ close(fd);
+ }
+
+ ksft_test_result_pass("clockid=%d\n", clockid);
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, status, len, fd;
+ char buf[4096];
+ pid_t pid;
+ struct timespec btime_now, mtime_now;
+
+ nscheck();
+
+ ksft_set_plan(3);
+
+ clock_gettime(CLOCK_MONOTONIC, &mtime_now);
+ clock_gettime(CLOCK_BOOTTIME, &btime_now);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("unshare");
+
+ len = snprintf(buf, sizeof(buf), "%d %d 0\n%d %d 0",
+ CLOCK_MONOTONIC, 70 * 24 * 3600,
+ CLOCK_BOOTTIME, 9 * 24 * 3600);
+ fd = open("/proc/self/timens_offsets", O_WRONLY);
+ if (fd < 0)
+ return pr_perror("/proc/self/timens_offsets");
+
+ if (write(fd, buf, len) != len)
+ return pr_perror("/proc/self/timens_offsets");
+
+ close(fd);
+ mtime_now.tv_sec += 70 * 24 * 3600;
+ btime_now.tv_sec += 9 * 24 * 3600;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("Unable to fork");
+ if (pid == 0) {
+ ret = 0;
+ ret |= run_test(CLOCK_BOOTTIME, btime_now);
+ ret |= run_test(CLOCK_MONOTONIC, mtime_now);
+ ret |= run_test(CLOCK_BOOTTIME_ALARM, btime_now);
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("Unable to wait the child process");
+
+ if (WIFEXITED(status))
+ return WEXITSTATUS(status);
+
+ return 1;
+}
+
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 31/36] selftest/timens: Add a test for timerfd
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
Check that timerfd_create() takes into account clock offsets.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/timerfd.c | 129 ++++++++++++++++++++++
3 files changed, 131 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/timerfd.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 27a693229ce1..b609f6ee9fb9 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1 +1,2 @@
timens
+timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index b877efb78974..66b90cd28e5c 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens
+TEST_GEN_PROGS := timens timerfd
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/timens/timerfd.c b/tools/testing/selftests/timens/timerfd.c
new file mode 100644
index 000000000000..b87076aae040
--- /dev/null
+++ b/tools/testing/selftests/timens/timerfd.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+
+#include <sys/timerfd.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+
+#include "log.h"
+#include "timens.h"
+
+static int tclock_gettime(clock_t clockid, struct timespec *now)
+{
+ if (clockid == CLOCK_BOOTTIME_ALARM)
+ clockid = CLOCK_BOOTTIME;
+ return clock_gettime(clockid, now);
+}
+
+int run_test(int clockid, struct timespec now)
+{
+ struct itimerspec new_value;
+ long long elapsed;
+ int fd, i;
+
+ if (tclock_gettime(clockid, &now))
+ return pr_perror("clock_gettime(%d)", clockid);
+
+ for (i = 0; i < 2; i++) {
+ int flags = 0;
+
+ new_value.it_value.tv_sec = 3600;
+ new_value.it_value.tv_nsec = 0;
+ new_value.it_interval.tv_sec = 1;
+ new_value.it_interval.tv_nsec = 0;
+
+ if (i == 1) {
+ new_value.it_value.tv_sec += now.tv_sec;
+ new_value.it_value.tv_nsec += now.tv_nsec;
+ }
+
+ fd = timerfd_create(clockid, 0);
+ if (fd == -1)
+ return pr_perror("timerfd_create(%d)", clockid);
+
+ if (i == 1)
+ flags |= TFD_TIMER_ABSTIME;
+
+ if (timerfd_settime(fd, flags, &new_value, NULL))
+ return pr_perror("timerfd_settime(%d)", clockid);
+
+ if (timerfd_gettime(fd, &new_value))
+ return pr_perror("timerfd_gettime(%d)", clockid);
+
+ elapsed = new_value.it_value.tv_sec;
+ if (abs(elapsed - 3600) > 60) {
+ ksft_test_result_fail("clockid: %d elapsed: %lld\n",
+ clockid, elapsed);
+ return 1;
+ }
+
+ close(fd);
+ }
+
+ ksft_test_result_pass("clockid=%d\n", clockid);
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, status, len, fd;
+ char buf[4096];
+ pid_t pid;
+ struct timespec btime_now, mtime_now;
+
+ nscheck();
+
+ ksft_set_plan(3);
+
+ clock_gettime(CLOCK_MONOTONIC, &mtime_now);
+ clock_gettime(CLOCK_BOOTTIME, &btime_now);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("unshare");
+
+ len = snprintf(buf, sizeof(buf), "%d %d 0\n%d %d 0",
+ CLOCK_MONOTONIC, 70 * 24 * 3600,
+ CLOCK_BOOTTIME, 9 * 24 * 3600);
+ fd = open("/proc/self/timens_offsets", O_WRONLY);
+ if (fd < 0)
+ return pr_perror("/proc/self/timens_offsets");
+
+ if (write(fd, buf, len) != len)
+ return pr_perror("/proc/self/timens_offsets");
+
+ close(fd);
+ mtime_now.tv_sec += 70 * 24 * 3600;
+ btime_now.tv_sec += 9 * 24 * 3600;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("Unable to fork");
+ if (pid == 0) {
+ ret = 0;
+ ret |= run_test(CLOCK_BOOTTIME, btime_now);
+ ret |= run_test(CLOCK_MONOTONIC, mtime_now);
+ ret |= run_test(CLOCK_BOOTTIME_ALARM, btime_now);
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("Unable to wait the child process");
+
+ if (WIFEXITED(status))
+ return WEXITSTATUS(status);
+
+ return 1;
+}
+
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 32/36] selftest/timens: Add a test for clock_nanosleep()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
Check that clock_nanosleep() takes into account clock offsets.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
.../selftests/timens/clock_nanosleep.c | 102 ++++++++++++++++++
3 files changed, 104 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/clock_nanosleep.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index b609f6ee9fb9..9b6c8ddac2c8 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,2 +1,3 @@
+clock_nanosleep
timens
timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 66b90cd28e5c..76a1dc891184 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd
+TEST_GEN_PROGS := timens timerfd clock_nanosleep
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/timens/clock_nanosleep.c b/tools/testing/selftests/timens/clock_nanosleep.c
new file mode 100644
index 000000000000..7956e65d3032
--- /dev/null
+++ b/tools/testing/selftests/timens/clock_nanosleep.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+
+#include <sys/timerfd.h>
+#include <sys/syscall.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+
+#include "log.h"
+#include "timens.h"
+
+static long long get_elapsed_time(int clockid, struct timespec *start)
+{
+ struct timespec curr;
+ long long secs, nsecs;
+
+ if (clock_gettime(clockid, &curr) == -1)
+ return pr_perror("clock_gettime");
+
+ secs = curr.tv_sec - start->tv_sec;
+ nsecs = curr.tv_nsec - start->tv_nsec;
+ if (nsecs < 0) {
+ secs--;
+ nsecs += 1000000000;
+ }
+ if (nsecs > 1000000000) {
+ secs++;
+ nsecs -= 1000000000;
+ }
+ return secs * 1000 + nsecs / 1000000;
+}
+
+int run_test(int clockid)
+{
+ long long elapsed;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct timespec now = {};
+ struct timespec start;
+
+ if (clock_gettime(clockid, &start) == -1)
+ return pr_perror("clock_gettime");
+
+
+ if (i == 1) {
+ now.tv_sec = start.tv_sec;
+ now.tv_nsec = start.tv_nsec;
+ }
+
+ now.tv_sec += 2;
+ clock_nanosleep(clockid, i ? TIMER_ABSTIME : 0, &now, NULL);
+
+ elapsed = get_elapsed_time(clockid, &start);
+ if (elapsed < 1900 || elapsed > 2100) {
+ pr_fail("clockid: %d abs: %d elapsed: %lld\n",
+ clockid, i, elapsed);
+ return 1;
+ }
+ ksft_test_result_pass("clockid: %d abs:%d\n", clockid, i);
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, nsfd;
+
+ nscheck();
+
+ ksft_set_plan(4);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("unshare");
+
+ if (_settime(CLOCK_MONOTONIC, 7 * 24 * 3600))
+ return 1;
+ if (_settime(CLOCK_BOOTTIME, 9 * 24 * 3600))
+ return 1;
+
+ nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
+ if (nsfd < 0)
+ return pr_perror("Unable to open timens_for_children");
+
+ if (setns(nsfd, CLONE_NEWTIME))
+ return pr_perror("Unable to set timens");
+
+ ret = 0;
+ ret |= run_test(CLOCK_MONOTONIC);
+ ret |= run_test(CLOCK_BOOTTIME_ALARM);
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+}
+
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 32/36] selftest/timens: Add a test for clock_nanosleep()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
Check that clock_nanosleep() takes into account clock offsets.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
.../selftests/timens/clock_nanosleep.c | 102 ++++++++++++++++++
3 files changed, 104 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/clock_nanosleep.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index b609f6ee9fb9..9b6c8ddac2c8 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,2 +1,3 @@
+clock_nanosleep
timens
timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 66b90cd28e5c..76a1dc891184 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd
+TEST_GEN_PROGS := timens timerfd clock_nanosleep
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/timens/clock_nanosleep.c b/tools/testing/selftests/timens/clock_nanosleep.c
new file mode 100644
index 000000000000..7956e65d3032
--- /dev/null
+++ b/tools/testing/selftests/timens/clock_nanosleep.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+
+#include <sys/timerfd.h>
+#include <sys/syscall.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+
+#include "log.h"
+#include "timens.h"
+
+static long long get_elapsed_time(int clockid, struct timespec *start)
+{
+ struct timespec curr;
+ long long secs, nsecs;
+
+ if (clock_gettime(clockid, &curr) == -1)
+ return pr_perror("clock_gettime");
+
+ secs = curr.tv_sec - start->tv_sec;
+ nsecs = curr.tv_nsec - start->tv_nsec;
+ if (nsecs < 0) {
+ secs--;
+ nsecs += 1000000000;
+ }
+ if (nsecs > 1000000000) {
+ secs++;
+ nsecs -= 1000000000;
+ }
+ return secs * 1000 + nsecs / 1000000;
+}
+
+int run_test(int clockid)
+{
+ long long elapsed;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct timespec now = {};
+ struct timespec start;
+
+ if (clock_gettime(clockid, &start) == -1)
+ return pr_perror("clock_gettime");
+
+
+ if (i == 1) {
+ now.tv_sec = start.tv_sec;
+ now.tv_nsec = start.tv_nsec;
+ }
+
+ now.tv_sec += 2;
+ clock_nanosleep(clockid, i ? TIMER_ABSTIME : 0, &now, NULL);
+
+ elapsed = get_elapsed_time(clockid, &start);
+ if (elapsed < 1900 || elapsed > 2100) {
+ pr_fail("clockid: %d abs: %d elapsed: %lld\n",
+ clockid, i, elapsed);
+ return 1;
+ }
+ ksft_test_result_pass("clockid: %d abs:%d\n", clockid, i);
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, nsfd;
+
+ nscheck();
+
+ ksft_set_plan(4);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("unshare");
+
+ if (_settime(CLOCK_MONOTONIC, 7 * 24 * 3600))
+ return 1;
+ if (_settime(CLOCK_BOOTTIME, 9 * 24 * 3600))
+ return 1;
+
+ nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
+ if (nsfd < 0)
+ return pr_perror("Unable to open timens_for_children");
+
+ if (setns(nsfd, CLONE_NEWTIME))
+ return pr_perror("Unable to set timens");
+
+ ret = 0;
+ ret |= run_test(CLOCK_MONOTONIC);
+ ret |= run_test(CLOCK_BOOTTIME_ALARM);
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+}
+
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 33/36] selftest/timens: Add procfs selftest
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, Andrei Vagin
Check that /proc/uptime is correct inside a new time namespace.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/procfs.c | 144 ++++++++++++++++++++++
3 files changed, 146 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/procfs.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 9b6c8ddac2c8..94ffdd9cead7 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,3 +1,4 @@
clock_nanosleep
+procfs
timens
timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 76a1dc891184..f96f50d1fef8 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd clock_nanosleep
+TEST_GEN_PROGS := timens timerfd clock_nanosleep procfs
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/timens/procfs.c b/tools/testing/selftests/timens/procfs.c
new file mode 100644
index 000000000000..3c3c6e634d50
--- /dev/null
+++ b/tools/testing/selftests/timens/procfs.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <math.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+#include <time.h>
+
+#include "log.h"
+#include "timens.h"
+
+/*
+ * Test shouldn't be run for a day, so add 10 days to child
+ * time and check parent's time to be in the same day.
+ */
+#define MAX_TEST_TIME_SEC (60*5)
+#define DAY_IN_SEC (60*60*24)
+#define TEN_DAYS_IN_SEC (10*DAY_IN_SEC)
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+static int child_ns, parent_ns;
+
+static int switch_ns(int fd)
+{
+ if (setns(fd, CLONE_NEWTIME))
+ return pr_perror("setns()");
+
+ return 0;
+}
+
+static int init_namespaces(void)
+{
+ char path[] = "/proc/self/ns/time_for_children";
+ struct stat st1, st2;
+
+ parent_ns = open(path, O_RDONLY);
+ if (parent_ns <= 0)
+ return pr_perror("Unable to open %s", path);
+
+ if (fstat(parent_ns, &st1))
+ return pr_perror("Unable to stat the parent timens");
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ child_ns = open(path, O_RDONLY);
+ if (child_ns <= 0)
+ return pr_perror("Unable to open %s", path);
+
+ if (fstat(child_ns, &st2))
+ return pr_perror("Unable to stat the timens");
+
+ if (st1.st_ino == st2.st_ino)
+ return pr_err("The same child_ns after CLONE_NEWTIME");
+
+ if (_settime(CLOCK_BOOTTIME, TEN_DAYS_IN_SEC))
+ return -1;
+
+ return 0;
+}
+
+static int read_proc_uptime(struct timespec *uptime)
+{
+ unsigned long up_sec, up_nsec;
+ FILE *proc;
+
+ proc = fopen("/proc/uptime", "r");
+ if (proc == NULL) {
+ pr_perror("Unable to open /proc/uptime");
+ return -1;
+ }
+
+ if (fscanf(proc, "%lu.%02lu", &up_sec, &up_nsec) != 2) {
+ if (errno) {
+ pr_perror("fscanf");
+ return -errno;
+ }
+ pr_err("failed to parse /proc/uptime");
+ return -1;
+ }
+ fclose(proc);
+
+ uptime->tv_sec = up_sec;
+ uptime->tv_nsec = up_nsec;
+ return 0;
+}
+
+static int check_uptime(void)
+{
+ struct timespec uptime_new, uptime_old;
+ time_t uptime_expected;
+ double prec = MAX_TEST_TIME_SEC;
+
+ if (switch_ns(parent_ns))
+ return pr_err("switch_ns(%d)", parent_ns);
+
+ if (read_proc_uptime(&uptime_old))
+ return 1;
+
+ if (switch_ns(child_ns))
+ return pr_err("switch_ns(%d)", child_ns);
+
+ if (read_proc_uptime(&uptime_new))
+ return 1;
+
+ uptime_expected = uptime_old.tv_sec + TEN_DAYS_IN_SEC;
+ if (fabs(difftime(uptime_new.tv_sec, uptime_expected)) > prec) {
+ pr_fail("uptime in /proc/uptime: old %ld, new %ld [%ld]",
+ uptime_old.tv_sec, uptime_new.tv_sec,
+ uptime_old.tv_sec + TEN_DAYS_IN_SEC);
+ return 1;
+ }
+
+ ksft_test_result_pass("Passed for /proc/uptime\n");
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret = 0;
+
+ nscheck();
+
+ ksft_set_plan(1);
+
+ if (init_namespaces())
+ return 1;
+
+ ret |= check_uptime();
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 33/36] selftest/timens: Add procfs selftest
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Dmitry Safonov, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
Check that /proc/uptime is correct inside a new time namespace.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/procfs.c | 144 ++++++++++++++++++++++
3 files changed, 146 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/procfs.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 9b6c8ddac2c8..94ffdd9cead7 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,3 +1,4 @@
clock_nanosleep
+procfs
timens
timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 76a1dc891184..f96f50d1fef8 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd clock_nanosleep
+TEST_GEN_PROGS := timens timerfd clock_nanosleep procfs
CFLAGS := -Wall -Werror
diff --git a/tools/testing/selftests/timens/procfs.c b/tools/testing/selftests/timens/procfs.c
new file mode 100644
index 000000000000..3c3c6e634d50
--- /dev/null
+++ b/tools/testing/selftests/timens/procfs.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <math.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+#include <time.h>
+
+#include "log.h"
+#include "timens.h"
+
+/*
+ * Test shouldn't be run for a day, so add 10 days to child
+ * time and check parent's time to be in the same day.
+ */
+#define MAX_TEST_TIME_SEC (60*5)
+#define DAY_IN_SEC (60*60*24)
+#define TEN_DAYS_IN_SEC (10*DAY_IN_SEC)
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+static int child_ns, parent_ns;
+
+static int switch_ns(int fd)
+{
+ if (setns(fd, CLONE_NEWTIME))
+ return pr_perror("setns()");
+
+ return 0;
+}
+
+static int init_namespaces(void)
+{
+ char path[] = "/proc/self/ns/time_for_children";
+ struct stat st1, st2;
+
+ parent_ns = open(path, O_RDONLY);
+ if (parent_ns <= 0)
+ return pr_perror("Unable to open %s", path);
+
+ if (fstat(parent_ns, &st1))
+ return pr_perror("Unable to stat the parent timens");
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ child_ns = open(path, O_RDONLY);
+ if (child_ns <= 0)
+ return pr_perror("Unable to open %s", path);
+
+ if (fstat(child_ns, &st2))
+ return pr_perror("Unable to stat the timens");
+
+ if (st1.st_ino == st2.st_ino)
+ return pr_err("The same child_ns after CLONE_NEWTIME");
+
+ if (_settime(CLOCK_BOOTTIME, TEN_DAYS_IN_SEC))
+ return -1;
+
+ return 0;
+}
+
+static int read_proc_uptime(struct timespec *uptime)
+{
+ unsigned long up_sec, up_nsec;
+ FILE *proc;
+
+ proc = fopen("/proc/uptime", "r");
+ if (proc == NULL) {
+ pr_perror("Unable to open /proc/uptime");
+ return -1;
+ }
+
+ if (fscanf(proc, "%lu.%02lu", &up_sec, &up_nsec) != 2) {
+ if (errno) {
+ pr_perror("fscanf");
+ return -errno;
+ }
+ pr_err("failed to parse /proc/uptime");
+ return -1;
+ }
+ fclose(proc);
+
+ uptime->tv_sec = up_sec;
+ uptime->tv_nsec = up_nsec;
+ return 0;
+}
+
+static int check_uptime(void)
+{
+ struct timespec uptime_new, uptime_old;
+ time_t uptime_expected;
+ double prec = MAX_TEST_TIME_SEC;
+
+ if (switch_ns(parent_ns))
+ return pr_err("switch_ns(%d)", parent_ns);
+
+ if (read_proc_uptime(&uptime_old))
+ return 1;
+
+ if (switch_ns(child_ns))
+ return pr_err("switch_ns(%d)", child_ns);
+
+ if (read_proc_uptime(&uptime_new))
+ return 1;
+
+ uptime_expected = uptime_old.tv_sec + TEN_DAYS_IN_SEC;
+ if (fabs(difftime(uptime_new.tv_sec, uptime_expected)) > prec) {
+ pr_fail("uptime in /proc/uptime: old %ld, new %ld [%ld]",
+ uptime_old.tv_sec, uptime_new.tv_sec,
+ uptime_old.tv_sec + TEN_DAYS_IN_SEC);
+ return 1;
+ }
+
+ ksft_test_result_pass("Passed for /proc/uptime\n");
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret = 0;
+
+ nscheck();
+
+ ksft_set_plan(1);
+
+ if (init_namespaces())
+ return 1;
+
+ ret |= check_uptime();
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 34/36] selftest/timens: Add timer offsets test
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, Andrei Vagin
From: Andrei Vagin <avagin@openvz.org>
Check that timer_create() takes into account clock offsets.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 3 +-
tools/testing/selftests/timens/timer.c | 118 ++++++++++++++++++++++
3 files changed, 121 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/timer.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 94ffdd9cead7..3b7eda8f35ce 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,5 @@
clock_nanosleep
procfs
timens
+timer
timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index f96f50d1fef8..ae1ffd24cc43 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,5 +1,6 @@
-TEST_GEN_PROGS := timens timerfd clock_nanosleep procfs
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs
CFLAGS := -Wall -Werror
+LDFLAGS := -lrt
include ../lib.mk
diff --git a/tools/testing/selftests/timens/timer.c b/tools/testing/selftests/timens/timer.c
new file mode 100644
index 000000000000..45a9dd3cbb12
--- /dev/null
+++ b/tools/testing/selftests/timens/timer.c
@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <signal.h>
+#include <time.h>
+
+#include "log.h"
+#include "timens.h"
+
+int run_test(int clockid, struct timespec now)
+{
+ struct itimerspec new_value;
+ long long elapsed;
+ timer_t fd;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct sigevent sevp = {.sigev_notify = SIGEV_NONE};
+ int flags = 0;
+
+ new_value.it_value.tv_sec = 3600;
+ new_value.it_value.tv_nsec = 0;
+ new_value.it_interval.tv_sec = 1;
+ new_value.it_interval.tv_nsec = 0;
+
+ if (i == 1) {
+ new_value.it_value.tv_sec += now.tv_sec;
+ new_value.it_value.tv_nsec += now.tv_nsec;
+ }
+
+ if (timer_create(clockid, &sevp, &fd) == -1)
+ return pr_perror("timerfd_create");
+
+ if (i == 1)
+ flags |= TIMER_ABSTIME;
+ if (timer_settime(fd, flags, &new_value, NULL) == -1)
+ return pr_perror("timerfd_settime");
+
+ if (timer_gettime(fd, &new_value) == -1)
+ return pr_perror("timerfd_gettime");
+
+ elapsed = new_value.it_value.tv_sec;
+ if (abs(elapsed - 3600) > 60) {
+ ksft_test_result_fail("clockid: %d elapsed: %lld\n",
+ clockid, elapsed);
+ return 1;
+ }
+ }
+
+ ksft_test_result_pass("clockid=%d\n", clockid);
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, status, len, fd;
+ char buf[4096];
+ pid_t pid;
+ struct timespec btime_now, mtime_now;
+
+ nscheck();
+
+ ksft_set_plan(3);
+
+ clock_gettime(CLOCK_MONOTONIC, &mtime_now);
+ clock_gettime(CLOCK_BOOTTIME, &btime_now);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("unshare");
+
+ len = snprintf(buf, sizeof(buf), "%d %d 0\n%d %d 0",
+ CLOCK_MONOTONIC, 70 * 24 * 3600,
+ CLOCK_BOOTTIME, 9 * 24 * 3600);
+ fd = open("/proc/self/timens_offsets", O_WRONLY);
+ if (fd < 0)
+ return pr_perror("/proc/self/timens_offsets");
+
+ if (write(fd, buf, len) != len)
+ return pr_perror("/proc/self/timens_offsets");
+
+ close(fd);
+ mtime_now.tv_sec += 70 * 24 * 3600;
+ btime_now.tv_sec += 9 * 24 * 3600;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("Unable to fork");
+ if (pid == 0) {
+ ret = 0;
+ ret |= run_test(CLOCK_BOOTTIME, btime_now);
+ ret |= run_test(CLOCK_MONOTONIC, mtime_now);
+ ret |= run_test(CLOCK_BOOTTIME_ALARM, btime_now);
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("Unable to wait the child process");
+
+ if (WIFEXITED(status))
+ return WEXITSTATUS(status);
+
+ return 1;
+}
+
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 34/36] selftest/timens: Add timer offsets test
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@openvz.org>
Check that timer_create() takes into account clock offsets.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 3 +-
tools/testing/selftests/timens/timer.c | 118 ++++++++++++++++++++++
3 files changed, 121 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/timer.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 94ffdd9cead7..3b7eda8f35ce 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,5 @@
clock_nanosleep
procfs
timens
+timer
timerfd
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index f96f50d1fef8..ae1ffd24cc43 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,5 +1,6 @@
-TEST_GEN_PROGS := timens timerfd clock_nanosleep procfs
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs
CFLAGS := -Wall -Werror
+LDFLAGS := -lrt
include ../lib.mk
diff --git a/tools/testing/selftests/timens/timer.c b/tools/testing/selftests/timens/timer.c
new file mode 100644
index 000000000000..45a9dd3cbb12
--- /dev/null
+++ b/tools/testing/selftests/timens/timer.c
@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <signal.h>
+#include <time.h>
+
+#include "log.h"
+#include "timens.h"
+
+int run_test(int clockid, struct timespec now)
+{
+ struct itimerspec new_value;
+ long long elapsed;
+ timer_t fd;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct sigevent sevp = {.sigev_notify = SIGEV_NONE};
+ int flags = 0;
+
+ new_value.it_value.tv_sec = 3600;
+ new_value.it_value.tv_nsec = 0;
+ new_value.it_interval.tv_sec = 1;
+ new_value.it_interval.tv_nsec = 0;
+
+ if (i == 1) {
+ new_value.it_value.tv_sec += now.tv_sec;
+ new_value.it_value.tv_nsec += now.tv_nsec;
+ }
+
+ if (timer_create(clockid, &sevp, &fd) == -1)
+ return pr_perror("timerfd_create");
+
+ if (i == 1)
+ flags |= TIMER_ABSTIME;
+ if (timer_settime(fd, flags, &new_value, NULL) == -1)
+ return pr_perror("timerfd_settime");
+
+ if (timer_gettime(fd, &new_value) == -1)
+ return pr_perror("timerfd_gettime");
+
+ elapsed = new_value.it_value.tv_sec;
+ if (abs(elapsed - 3600) > 60) {
+ ksft_test_result_fail("clockid: %d elapsed: %lld\n",
+ clockid, elapsed);
+ return 1;
+ }
+ }
+
+ ksft_test_result_pass("clockid=%d\n", clockid);
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, status, len, fd;
+ char buf[4096];
+ pid_t pid;
+ struct timespec btime_now, mtime_now;
+
+ nscheck();
+
+ ksft_set_plan(3);
+
+ clock_gettime(CLOCK_MONOTONIC, &mtime_now);
+ clock_gettime(CLOCK_BOOTTIME, &btime_now);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("unshare");
+
+ len = snprintf(buf, sizeof(buf), "%d %d 0\n%d %d 0",
+ CLOCK_MONOTONIC, 70 * 24 * 3600,
+ CLOCK_BOOTTIME, 9 * 24 * 3600);
+ fd = open("/proc/self/timens_offsets", O_WRONLY);
+ if (fd < 0)
+ return pr_perror("/proc/self/timens_offsets");
+
+ if (write(fd, buf, len) != len)
+ return pr_perror("/proc/self/timens_offsets");
+
+ close(fd);
+ mtime_now.tv_sec += 70 * 24 * 3600;
+ btime_now.tv_sec += 9 * 24 * 3600;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("Unable to fork");
+ if (pid == 0) {
+ ret = 0;
+ ret |= run_test(CLOCK_BOOTTIME, btime_now);
+ ret |= run_test(CLOCK_MONOTONIC, mtime_now);
+ ret |= run_test(CLOCK_BOOTTIME_ALARM, btime_now);
+
+ if (ret)
+ ksft_exit_fail();
+ ksft_exit_pass();
+ return ret;
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("Unable to wait the child process");
+
+ if (WIFEXITED(status))
+ return WEXITSTATUS(status);
+
+ return 1;
+}
+
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread
* [PATCHv6 35/36] selftests/timens: Add a simple perf test for clock_gettime()
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 2 +
tools/testing/selftests/timens/Makefile | 10 +-
tools/testing/selftests/timens/gettime_perf.c | 101 +++++++++++
.../selftests/timens/gettime_perf_cold.c | 160 ++++++++++++++++++
4 files changed, 271 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/timens/gettime_perf.c
create mode 100644 tools/testing/selftests/timens/gettime_perf_cold.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 3b7eda8f35ce..16292e4d08a5 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,6 @@
clock_nanosleep
+gettime_perf
+gettime_perf_cold
procfs
timens
timer
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index ae1ffd24cc43..97e0460eaf48 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,6 +1,12 @@
-TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf
+
+uname_M := $(shell uname -m 2>/dev/null || echo not)
+ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
+ifeq ($(ARCH),x86_64)
+TEST_GEN_PROGS += gettime_perf_cold
+endif
CFLAGS := -Wall -Werror
-LDFLAGS := -lrt
+LDFLAGS := -lrt -ldl
include ../lib.mk
diff --git a/tools/testing/selftests/timens/gettime_perf.c b/tools/testing/selftests/timens/gettime_perf.c
new file mode 100644
index 000000000000..f7d7832c0293
--- /dev/null
+++ b/tools/testing/selftests/timens/gettime_perf.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <time.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <dlfcn.h>
+
+#include "log.h"
+#include "timens.h"
+
+//#define TEST_SYSCALL
+
+typedef int (*vgettime_t)(clockid_t, struct timespec *);
+
+vgettime_t vdso_clock_gettime;
+
+static void fill_function_pointers(void)
+{
+ void *vdso = dlopen("linux-vdso.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso)
+ vdso = dlopen("linux-gate.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso) {
+ pr_err("[WARN]\tfailed to find vDSO\n");
+ return;
+ }
+
+ vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__vdso_clock_gettime");
+ if (!vdso_clock_gettime)
+ pr_err("Warning: failed to find clock_gettime in vDSO\n");
+
+}
+
+static void test(clock_t clockid, char *clockstr, bool in_ns)
+{
+ struct timespec tp, start;
+ long i = 0;
+ const int timeout = 3;
+
+#ifndef TEST_SYSCALL
+ vdso_clock_gettime(clockid, &start);
+#else
+ syscall(__NR_clock_gettime, clockid, &start);
+#endif
+ tp = start;
+ for (tp = start; start.tv_sec + timeout > tp.tv_sec ||
+ (start.tv_sec + timeout == tp.tv_sec &&
+ start.tv_nsec > tp.tv_nsec); i++) {
+#ifndef TEST_SYSCALL
+ vdso_clock_gettime(clockid, &tp);
+#else
+ syscall(__NR_clock_gettime, clockid, &tp);
+#endif
+ }
+
+ ksft_test_result_pass("%s:\tclock: %10s\tcycles:\t%10ld\n",
+ in_ns ? "ns" : "host", clockstr, i);
+}
+
+int main(int argc, char *argv[])
+{
+ time_t offset = 10;
+ int nsfd;
+
+ ksft_set_plan(4);
+
+ fill_function_pointers();
+
+ test(CLOCK_MONOTONIC, "monotonic", false);
+ test(CLOCK_BOOTTIME, "boottime", false);
+
+ nscheck();
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
+ if (nsfd < 0)
+ return pr_perror("Can't open a time namespace");
+
+ if (_settime(CLOCK_MONOTONIC, offset))
+ return 1;
+ if (_settime(CLOCK_BOOTTIME, offset))
+ return 1;
+
+ if (setns(nsfd, CLONE_NEWTIME))
+ return pr_perror("setns");
+
+ test(CLOCK_MONOTONIC, "monotonic", true);
+ test(CLOCK_BOOTTIME, "boottime", true);
+
+ ksft_exit_pass();
+ return 0;
+}
diff --git a/tools/testing/selftests/timens/gettime_perf_cold.c b/tools/testing/selftests/timens/gettime_perf_cold.c
new file mode 100644
index 000000000000..2ab0869744a6
--- /dev/null
+++ b/tools/testing/selftests/timens/gettime_perf_cold.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <time.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <string.h>
+#include <dlfcn.h>
+#include <signal.h>
+
+#include "log.h"
+#include "timens.h"
+
+#define PAGE_SIZE 4096
+#define CACHE_LINE_SIZE 64
+
+typedef int (*vgettime_t)(clockid_t, struct timespec *);
+
+vgettime_t vdso_clock_gettime;
+
+static void fill_function_pointers(void)
+{
+ void *vdso = dlopen("linux-vdso.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso)
+ vdso = dlopen("linux-gate.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso) {
+ pr_err("[WARN]\tfailed to find vDSO\n");
+ return;
+ }
+
+ vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__vdso_clock_gettime");
+ if (!vdso_clock_gettime)
+ pr_err("Warning: failed to find clock_gettime in vDSO\n");
+
+}
+
+static inline __attribute__((always_inline)) unsigned long long rdtsc(void)
+{
+ unsigned int hi, lo;
+
+ __asm__ __volatile__ ("rdtsc" : "=a"(lo), "=d"(hi));
+ return ((unsigned long long) lo) | (((unsigned long long)hi) << 32);
+}
+
+static inline __attribute__((always_inline)) void test(clock_t clockid, char *clockstr)
+{
+ struct timespec tp;
+ long long s, e;
+
+ s = rdtsc();
+ vdso_clock_gettime(clockid, &tp);
+ e = rdtsc();
+ printf("%lld\n", e - s);
+}
+
+static inline void clflush(volatile void *__p)
+{
+ asm volatile("clflush %0" : "+m"(*(volatile char *)__p));
+}
+
+void *pg_addr;
+void sigh(int sig)
+{
+ void *addr;
+
+ addr = mmap(pg_addr, PAGE_SIZE, PROT_READ,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
+ if (addr != pg_addr) {
+ pr_perror("Unable to map %lx", (long) pg_addr);
+ exit(1);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ time_t offset = 10;
+ void *vdso_start = 0, *vdso_end = 0;
+ void *vvar_start = 0, *vvar_end = 0;
+ char buf[PAGE_SIZE];
+ int nsfd, i;
+ FILE *maps;
+
+ fill_function_pointers();
+ if (argc == 1)
+ goto out;
+ nscheck();
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
+ if (nsfd < 0)
+ return pr_perror("Can't open a time namespace");
+
+ if (_settime(CLOCK_MONOTONIC, offset))
+ return 1;
+
+ if (setns(nsfd, CLONE_NEWTIME))
+ return pr_perror("setns");
+
+out:
+ maps = fopen("/proc/self/maps", "r");
+ if (!maps) {
+ pr_perror("Unable to open /proc/self/maps");
+ return 1;
+ }
+
+ while (fgets(buf, sizeof(buf), maps)) {
+ unsigned long start, end;
+ char tail[PAGE_SIZE];
+ int r;
+
+ r = sscanf(buf, "%lx-%lx %*s %*s %*s %*s %s\n", &start, &end, tail);
+
+ if (r < 3)
+ continue;
+
+ if (strcmp(tail, "[vdso]") == 0) {
+ vdso_start = (void *)start;
+ vdso_end = (void *)end;
+ }
+ if (strcmp(tail, "[vvar]") == 0) {
+ vvar_start = (void *)start;
+ vvar_end = (void *)end;
+ }
+ }
+ if (!vvar_start || !vdso_start) {
+ pr_err("Unable to find vdso\n");
+ return 1;
+ }
+
+ /* Map zero pages instead of unreadable vdso pages. */
+ signal(SIGSEGV, sigh);
+ signal(SIGBUS, sigh);
+ for (pg_addr = vdso_start; pg_addr < vdso_end; pg_addr += PAGE_SIZE)
+ buf[0] += *(char *)pg_addr;
+ for (pg_addr = vvar_start; pg_addr < vvar_end; pg_addr += PAGE_SIZE)
+ buf[0] += *(char *)pg_addr;
+ signal(SIGSEGV, SIG_DFL);
+ signal(SIGBUS, SIG_DFL);
+
+ for (i = 0; i < 10240; i++) {
+ void *p;
+
+ for (p = vdso_start; p < vdso_end; p += CACHE_LINE_SIZE)
+ clflush(p);
+ for (p = vvar_start; p < vvar_end; p += CACHE_LINE_SIZE)
+ clflush(p);
+ test(CLOCK_MONOTONIC, "monotonic");
+ }
+ return 0;
+}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 35/36] selftests/timens: Add a simple perf test for clock_gettime()
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 2 +
tools/testing/selftests/timens/Makefile | 10 +-
tools/testing/selftests/timens/gettime_perf.c | 101 +++++++++++
.../selftests/timens/gettime_perf_cold.c | 160 ++++++++++++++++++
4 files changed, 271 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/timens/gettime_perf.c
create mode 100644 tools/testing/selftests/timens/gettime_perf_cold.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 3b7eda8f35ce..16292e4d08a5 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,6 @@
clock_nanosleep
+gettime_perf
+gettime_perf_cold
procfs
timens
timer
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index ae1ffd24cc43..97e0460eaf48 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,6 +1,12 @@
-TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf
+
+uname_M := $(shell uname -m 2>/dev/null || echo not)
+ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
+ifeq ($(ARCH),x86_64)
+TEST_GEN_PROGS += gettime_perf_cold
+endif
CFLAGS := -Wall -Werror
-LDFLAGS := -lrt
+LDFLAGS := -lrt -ldl
include ../lib.mk
diff --git a/tools/testing/selftests/timens/gettime_perf.c b/tools/testing/selftests/timens/gettime_perf.c
new file mode 100644
index 000000000000..f7d7832c0293
--- /dev/null
+++ b/tools/testing/selftests/timens/gettime_perf.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <time.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <dlfcn.h>
+
+#include "log.h"
+#include "timens.h"
+
+//#define TEST_SYSCALL
+
+typedef int (*vgettime_t)(clockid_t, struct timespec *);
+
+vgettime_t vdso_clock_gettime;
+
+static void fill_function_pointers(void)
+{
+ void *vdso = dlopen("linux-vdso.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso)
+ vdso = dlopen("linux-gate.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso) {
+ pr_err("[WARN]\tfailed to find vDSO\n");
+ return;
+ }
+
+ vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__vdso_clock_gettime");
+ if (!vdso_clock_gettime)
+ pr_err("Warning: failed to find clock_gettime in vDSO\n");
+
+}
+
+static void test(clock_t clockid, char *clockstr, bool in_ns)
+{
+ struct timespec tp, start;
+ long i = 0;
+ const int timeout = 3;
+
+#ifndef TEST_SYSCALL
+ vdso_clock_gettime(clockid, &start);
+#else
+ syscall(__NR_clock_gettime, clockid, &start);
+#endif
+ tp = start;
+ for (tp = start; start.tv_sec + timeout > tp.tv_sec ||
+ (start.tv_sec + timeout == tp.tv_sec &&
+ start.tv_nsec > tp.tv_nsec); i++) {
+#ifndef TEST_SYSCALL
+ vdso_clock_gettime(clockid, &tp);
+#else
+ syscall(__NR_clock_gettime, clockid, &tp);
+#endif
+ }
+
+ ksft_test_result_pass("%s:\tclock: %10s\tcycles:\t%10ld\n",
+ in_ns ? "ns" : "host", clockstr, i);
+}
+
+int main(int argc, char *argv[])
+{
+ time_t offset = 10;
+ int nsfd;
+
+ ksft_set_plan(4);
+
+ fill_function_pointers();
+
+ test(CLOCK_MONOTONIC, "monotonic", false);
+ test(CLOCK_BOOTTIME, "boottime", false);
+
+ nscheck();
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
+ if (nsfd < 0)
+ return pr_perror("Can't open a time namespace");
+
+ if (_settime(CLOCK_MONOTONIC, offset))
+ return 1;
+ if (_settime(CLOCK_BOOTTIME, offset))
+ return 1;
+
+ if (setns(nsfd, CLONE_NEWTIME))
+ return pr_perror("setns");
+
+ test(CLOCK_MONOTONIC, "monotonic", true);
+ test(CLOCK_BOOTTIME, "boottime", true);
+
+ ksft_exit_pass();
+ return 0;
+}
diff --git a/tools/testing/selftests/timens/gettime_perf_cold.c b/tools/testing/selftests/timens/gettime_perf_cold.c
new file mode 100644
index 000000000000..2ab0869744a6
--- /dev/null
+++ b/tools/testing/selftests/timens/gettime_perf_cold.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <time.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <string.h>
+#include <dlfcn.h>
+#include <signal.h>
+
+#include "log.h"
+#include "timens.h"
+
+#define PAGE_SIZE 4096
+#define CACHE_LINE_SIZE 64
+
+typedef int (*vgettime_t)(clockid_t, struct timespec *);
+
+vgettime_t vdso_clock_gettime;
+
+static void fill_function_pointers(void)
+{
+ void *vdso = dlopen("linux-vdso.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso)
+ vdso = dlopen("linux-gate.so.1",
+ RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
+ if (!vdso) {
+ pr_err("[WARN]\tfailed to find vDSO\n");
+ return;
+ }
+
+ vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__vdso_clock_gettime");
+ if (!vdso_clock_gettime)
+ pr_err("Warning: failed to find clock_gettime in vDSO\n");
+
+}
+
+static inline __attribute__((always_inline)) unsigned long long rdtsc(void)
+{
+ unsigned int hi, lo;
+
+ __asm__ __volatile__ ("rdtsc" : "=a"(lo), "=d"(hi));
+ return ((unsigned long long) lo) | (((unsigned long long)hi) << 32);
+}
+
+static inline __attribute__((always_inline)) void test(clock_t clockid, char *clockstr)
+{
+ struct timespec tp;
+ long long s, e;
+
+ s = rdtsc();
+ vdso_clock_gettime(clockid, &tp);
+ e = rdtsc();
+ printf("%lld\n", e - s);
+}
+
+static inline void clflush(volatile void *__p)
+{
+ asm volatile("clflush %0" : "+m"(*(volatile char *)__p));
+}
+
+void *pg_addr;
+void sigh(int sig)
+{
+ void *addr;
+
+ addr = mmap(pg_addr, PAGE_SIZE, PROT_READ,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
+ if (addr != pg_addr) {
+ pr_perror("Unable to map %lx", (long) pg_addr);
+ exit(1);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ time_t offset = 10;
+ void *vdso_start = 0, *vdso_end = 0;
+ void *vvar_start = 0, *vvar_end = 0;
+ char buf[PAGE_SIZE];
+ int nsfd, i;
+ FILE *maps;
+
+ fill_function_pointers();
+ if (argc == 1)
+ goto out;
+ nscheck();
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
+ if (nsfd < 0)
+ return pr_perror("Can't open a time namespace");
+
+ if (_settime(CLOCK_MONOTONIC, offset))
+ return 1;
+
+ if (setns(nsfd, CLONE_NEWTIME))
+ return pr_perror("setns");
+
+out:
+ maps = fopen("/proc/self/maps", "r");
+ if (!maps) {
+ pr_perror("Unable to open /proc/self/maps");
+ return 1;
+ }
+
+ while (fgets(buf, sizeof(buf), maps)) {
+ unsigned long start, end;
+ char tail[PAGE_SIZE];
+ int r;
+
+ r = sscanf(buf, "%lx-%lx %*s %*s %*s %*s %s\n", &start, &end, tail);
+
+ if (r < 3)
+ continue;
+
+ if (strcmp(tail, "[vdso]") == 0) {
+ vdso_start = (void *)start;
+ vdso_end = (void *)end;
+ }
+ if (strcmp(tail, "[vvar]") == 0) {
+ vvar_start = (void *)start;
+ vvar_end = (void *)end;
+ }
+ }
+ if (!vvar_start || !vdso_start) {
+ pr_err("Unable to find vdso\n");
+ return 1;
+ }
+
+ /* Map zero pages instead of unreadable vdso pages. */
+ signal(SIGSEGV, sigh);
+ signal(SIGBUS, sigh);
+ for (pg_addr = vdso_start; pg_addr < vdso_end; pg_addr += PAGE_SIZE)
+ buf[0] += *(char *)pg_addr;
+ for (pg_addr = vvar_start; pg_addr < vvar_end; pg_addr += PAGE_SIZE)
+ buf[0] += *(char *)pg_addr;
+ signal(SIGSEGV, SIG_DFL);
+ signal(SIGBUS, SIG_DFL);
+
+ for (i = 0; i < 10240; i++) {
+ void *p;
+
+ for (p = vdso_start; p < vdso_end; p += CACHE_LINE_SIZE)
+ clflush(p);
+ for (p = vvar_start; p < vvar_end; p += CACHE_LINE_SIZE)
+ clflush(p);
+ test(CLOCK_MONOTONIC, "monotonic");
+ }
+ return 0;
+}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* Re: [PATCHv6 35/36] selftests/timens: Add a simple perf test for clock_gettime()
2019-08-15 16:38 ` Dmitry Safonov
(?)
@ 2019-08-15 23:29 ` shuah
-1 siblings, 0 replies; 87+ messages in thread
From: shuah @ 2019-08-15 23:29 UTC (permalink / raw)
To: Dmitry Safonov, linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Adrian Reber, Andrei Vagin,
Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86, shuah
On 8/15/19 10:38 AM, Dmitry Safonov wrote:
> From: Andrei Vagin <avagin@gmail.com>
>
> Signed-off-by: Andrei Vagin <avagin@gmail.com>
> Co-developed-by: Dmitry Safonov <dima@arista.com>
> Signed-off-by: Dmitry Safonov <dima@arista.com>
> ---
> tools/testing/selftests/timens/.gitignore | 2 +
> tools/testing/selftests/timens/Makefile | 10 +-
> tools/testing/selftests/timens/gettime_perf.c | 101 +++++++++++
> .../selftests/timens/gettime_perf_cold.c | 160 ++++++++++++++++++
> 4 files changed, 271 insertions(+), 2 deletions(-)
> create mode 100644 tools/testing/selftests/timens/gettime_perf.c
> create mode 100644 tools/testing/selftests/timens/gettime_perf_cold.c
>
> diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
> index 3b7eda8f35ce..16292e4d08a5 100644
> --- a/tools/testing/selftests/timens/.gitignore
> +++ b/tools/testing/selftests/timens/.gitignore
> @@ -1,4 +1,6 @@
> clock_nanosleep
> +gettime_perf
> +gettime_perf_cold
> procfs
> timens
> timer
> diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
> index ae1ffd24cc43..97e0460eaf48 100644
> --- a/tools/testing/selftests/timens/Makefile
> +++ b/tools/testing/selftests/timens/Makefile
> @@ -1,6 +1,12 @@
> -TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs
> +TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf
> +
> +uname_M := $(shell uname -m 2>/dev/null || echo not)
> +ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
> +ifeq ($(ARCH),x86_64)
> +TEST_GEN_PROGS += gettime_perf_cold
> +endif
>
> CFLAGS := -Wall -Werror
> -LDFLAGS := -lrt
> +LDFLAGS := -lrt -ldl
>
> include ../lib.mk
> diff --git a/tools/testing/selftests/timens/gettime_perf.c b/tools/testing/selftests/timens/gettime_perf.c
> new file mode 100644
> index 000000000000..f7d7832c0293
> --- /dev/null
> +++ b/tools/testing/selftests/timens/gettime_perf.c
> @@ -0,0 +1,101 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <errno.h>
> +#include <fcntl.h>
> +#include <sched.h>
> +#include <time.h>
> +#include <stdio.h>
> +#include <unistd.h>
> +#include <sys/syscall.h>
> +#include <dlfcn.h>
> +
> +#include "log.h"
> +#include "timens.h"
> +
> +//#define TEST_SYSCALL
> +
How is this supposed to be used? When does TEST_SYSCALL
get defined?
> +typedef int (*vgettime_t)(clockid_t, struct timespec *);
> +
> +vgettime_t vdso_clock_gettime;
> +
> +static void fill_function_pointers(void)
> +{
> + void *vdso = dlopen("linux-vdso.so.1",
> + RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
> + if (!vdso)
> + vdso = dlopen("linux-gate.so.1",
> + RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
> + if (!vdso) {
> + pr_err("[WARN]\tfailed to find vDSO\n");
> + return;
> + }
> +
> + vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__vdso_clock_gettime");
> + if (!vdso_clock_gettime)
> + pr_err("Warning: failed to find clock_gettime in vDSO\n");
> +
> +}
> +
> +static void test(clock_t clockid, char *clockstr, bool in_ns)
> +{
> + struct timespec tp, start;
> + long i = 0;
> + const int timeout = 3;
> +
> +#ifndef TEST_SYSCALL
> + vdso_clock_gettime(clockid, &start);
> +#else
> + syscall(__NR_clock_gettime, clockid, &start);
> +#endif
Hmm. This doesn't look right. Does this test need to be compiled
with TEST_SYSCALL. Please find a way to do this without ifdef.
thanks,
-- Shuah
^ permalink raw reply [flat|nested] 87+ messages in thread
* [PATCHv6 36/36] selftest/timens: Check that a right vdso is mapped after fork and exec
2019-08-15 16:38 ` Dmitry Safonov
@ 2019-08-15 16:38 ` Dmitry Safonov
-1 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api,
x86
From: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/exec.c | 93 +++++++++++++++++++++++
3 files changed, 95 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/exec.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 16292e4d08a5..789f21e81028 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,5 @@
clock_nanosleep
+exec
gettime_perf
gettime_perf_cold
procfs
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 97e0460eaf48..b77fe22fa24d 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf exec
uname_M := $(shell uname -m 2>/dev/null || echo not)
ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
diff --git a/tools/testing/selftests/timens/exec.c b/tools/testing/selftests/timens/exec.c
new file mode 100644
index 000000000000..de7798832429
--- /dev/null
+++ b/tools/testing/selftests/timens/exec.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+
+#include "log.h"
+#include "timens.h"
+
+#define OFFSET (36000)
+
+int main(int argc, char *argv[])
+{
+ struct timespec now, tst;
+ int status, i;
+ pid_t pid;
+
+ if (argc > 1) {
+ if (sscanf(argv[1], "%ld", &now.tv_sec) != 1)
+ return pr_perror("sscanf");
+
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec) > 5)
+ return pr_fail("%ld %ld\n", now.tv_sec, tst.tv_sec);
+ }
+ }
+
+ nscheck();
+
+ ksft_set_plan(1);
+
+ clock_gettime(CLOCK_MONOTONIC, &now);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ if (_settime(CLOCK_MONOTONIC, OFFSET))
+ return 1;
+
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec) > 5)
+ return pr_fail("%ld %ld\n",
+ now.tv_sec, tst.tv_sec);
+ }
+
+ if (argc > 1)
+ return 0;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("fork");
+
+ if (pid == 0) {
+ char now_str[64];
+ char *cargv[] = {"exec", now_str, NULL};
+ char *cenv[] = {NULL};
+
+ /* Check that a child process is in the new timens. */
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec - OFFSET) > 5)
+ return pr_fail("%ld %ld\n",
+ now.tv_sec + OFFSET, tst.tv_sec);
+ }
+
+ /* Check that a proper vdso will be mapped after execve. */
+ snprintf(now_str, sizeof(now_str), "%ld", now.tv_sec + OFFSET);
+ execve("/proc/self/exe", cargv, cenv);
+ return pr_perror("execve");
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("waitpid");
+
+ if (status)
+ ksft_exit_fail();
+
+ ksft_test_result_pass("exec\n");
+ ksft_exit_pass();
+ return 0;
+}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread* [PATCHv6 36/36] selftest/timens: Check that a right vdso is mapped after fork and exec
@ 2019-08-15 16:38 ` Dmitry Safonov
0 siblings, 0 replies; 87+ messages in thread
From: Dmitry Safonov @ 2019-08-15 16:38 UTC (permalink / raw)
To: linux-kernel
Cc: Dmitry Safonov, Andrei Vagin, Dmitry Safonov, Adrian Reber,
Andrei Vagin, Andy Lutomirski, Arnd Bergmann, Christian Brauner,
Cyrill Gorcunov, Eric W. Biederman, H. Peter Anvin, Ingo Molnar,
Jann Horn, Jeff Dike, Oleg Nesterov, Pavel Emelyanov, Shuah Khan,
Thomas Gleixner, Vincenzo Frascino, containers, criu, linux-api
From: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/exec.c | 93 +++++++++++++++++++++++
3 files changed, 95 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/exec.c
diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 16292e4d08a5..789f21e81028 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,5 @@
clock_nanosleep
+exec
gettime_perf
gettime_perf_cold
procfs
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 97e0460eaf48..b77fe22fa24d 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs gettime_perf exec
uname_M := $(shell uname -m 2>/dev/null || echo not)
ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
diff --git a/tools/testing/selftests/timens/exec.c b/tools/testing/selftests/timens/exec.c
new file mode 100644
index 000000000000..de7798832429
--- /dev/null
+++ b/tools/testing/selftests/timens/exec.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+
+#include "log.h"
+#include "timens.h"
+
+#define OFFSET (36000)
+
+int main(int argc, char *argv[])
+{
+ struct timespec now, tst;
+ int status, i;
+ pid_t pid;
+
+ if (argc > 1) {
+ if (sscanf(argv[1], "%ld", &now.tv_sec) != 1)
+ return pr_perror("sscanf");
+
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec) > 5)
+ return pr_fail("%ld %ld\n", now.tv_sec, tst.tv_sec);
+ }
+ }
+
+ nscheck();
+
+ ksft_set_plan(1);
+
+ clock_gettime(CLOCK_MONOTONIC, &now);
+
+ if (unshare(CLONE_NEWTIME))
+ return pr_perror("Can't unshare() timens");
+
+ if (_settime(CLOCK_MONOTONIC, OFFSET))
+ return 1;
+
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec) > 5)
+ return pr_fail("%ld %ld\n",
+ now.tv_sec, tst.tv_sec);
+ }
+
+ if (argc > 1)
+ return 0;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("fork");
+
+ if (pid == 0) {
+ char now_str[64];
+ char *cargv[] = {"exec", now_str, NULL};
+ char *cenv[] = {NULL};
+
+ /* Check that a child process is in the new timens. */
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec - OFFSET) > 5)
+ return pr_fail("%ld %ld\n",
+ now.tv_sec + OFFSET, tst.tv_sec);
+ }
+
+ /* Check that a proper vdso will be mapped after execve. */
+ snprintf(now_str, sizeof(now_str), "%ld", now.tv_sec + OFFSET);
+ execve("/proc/self/exe", cargv, cenv);
+ return pr_perror("execve");
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("waitpid");
+
+ if (status)
+ ksft_exit_fail();
+
+ ksft_test_result_pass("exec\n");
+ ksft_exit_pass();
+ return 0;
+}
--
2.22.0
^ permalink raw reply related [flat|nested] 87+ messages in thread