[PATCHv8 16/34] hrtimers: Prepare hrtimer_nanosleep() for time namespaces

From: Dmitry Safonov <dima@arista.com>
To: linux-kernel@vger.kernel.org
Cc: Dmitry Safonov <0x7f454c46@gmail.com>,
	Andrei Vagin <avagin@gmail.com>, Dmitry Safonov <dima@arista.com>,
	Adrian Reber <adrian@lisas.de>, Andrei Vagin <avagin@openvz.org>,
	Andy Lutomirski <luto@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Christian Brauner <christian.brauner@ubuntu.com>,
	Cyrill Gorcunov <gorcunov@openvz.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
	Jann Horn <jannh@google.com>, Jeff Dike <jdike@addtoit.com>,
	Oleg Nesterov <oleg@redhat.com>,
	Pavel Emelyanov <xemul@virtuozzo.com>,
	Shuah Khan <shuah@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	containers@lists.linux-foundation.org, criu@openvz.org,
	linux-api@vger.kernel.org, x86@kernel.org
Subject: [PATCHv8 16/34] hrtimers: Prepare hrtimer_nanosleep() for time namespaces
Date: Tue, 12 Nov 2019 01:27:05 +0000	[thread overview]
Message-ID: <20191112012724.250792-17-dima@arista.com> (raw)
In-Reply-To: <20191112012724.250792-1-dima@arista.com>

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 ++--
 kernel/time/posix-timers.c     | 4 +++-
 tools/perf/examples/bpf/5sec.c | 6 ++++--
 5 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 1f98b52118f0..07c7c7b8b5cc 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -508,7 +508,7 @@ 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 7f31932216a1..b331128bd585 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1910,7 +1910,7 @@ 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;
@@ -1923,7 +1923,7 @@ 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;
@@ -1958,7 +1958,7 @@ 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
@@ -1978,7 +1978,7 @@ 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);
 }
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 473082b0b57f..75fee6e39e5a 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -1221,7 +1221,9 @@ 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);
 }
diff --git a/tools/perf/examples/bpf/5sec.c b/tools/perf/examples/bpf/5sec.c
index b9c203219691..e6b6181c6dc6 100644
--- a/tools/perf/examples/bpf/5sec.c
+++ b/tools/perf/examples/bpf/5sec.c
@@ -41,9 +41,11 @@
 
 #include <bpf.h>
 
-int probe(hrtimer_nanosleep, rqtp->tv_sec)(void *ctx, int err, long sec)
+#define NSEC_PER_SEC	1000000000L
+
+int probe(hrtimer_nanosleep, rqtp)(void *ctx, int err, long long sec)
 {
-	return sec == 5;
+	return sec / NSEC_PER_SEC == 5ULL;
 }
 
 license(GPL);
-- 
2.24.0

