* [PATCH 00/23] tracing: 'hist' triggers
@ 2016-02-26 16:01 Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 01/23] tracing: Update some tracing_map constants and comments Tom Zanussi
` (22 more replies)
0 siblings, 23 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
This is v15 of the 'hist triggers' patchset.
This is the same as v14 but with Masami's log2 test case added.
Patch 1 can be merged into patch 8 from v13, 'tracing: Add lock-free
tracing_map'. Following the v13 suggestions, I made a couple changes
to the tracing map constants to clarify the field relationships, and
added a couple missing comments I noticed while at it.
Changes from v14:
- Added Masami's log2 modifier test case.
Changes from v13:
- Changed tracing map defines to make the relationship between vals,
keys, and fields clear, and updated the code to use the new
defines.
- Added missing comments to a couple tracing map functions.
- Added 1 to the number of vals supported, to account for hitcount.
- Added parentheses around macro variables.
- Added "_FL" to hist_field_flags enums.
- Changed '!strncmp/strcmp' to 'strncmp/strcmp == 0' thoughout.
- Added '=' to attribute names.
- Added WARN_ON() where it made sense i.e. where field indices were
updated or used and it was't immediately clear from immdiate
context whether the index could possibly be invalid.
Changes from v12:
- Removed the unnecessary return val check and NULL assignment
pointed out by Namhyung, and did a small cleanup to make the error
handling in that function (create_hist_data()) more uniform, which
also included a small change to create_sort_keys().
- Removed the 'update cond flag' patch from the series since that's
now in tracing/for-next.
Changes from v11:
- Added tracing_map_lookup().
- Changed tracing_map_insert() to incorporate the hits/drops counter
updating. The changes allow clients to continue calling
tracing_map_insert() and update existing entries if desired, or
stop on the first drop, since the return value is still NULL in
that case.
- Changed the hist trigger code to continue calling
tracing_map_insert() rather than stopping on the first drop. The
idea is that there's no harm in continuing after the first drop -
if the user can't tolerate any drops, they'll still see a non-zero
drop count and can retry with a larger table, but if the user
doesn't care, the hit and drop counts are an accurate reflection
of how many events were tallied vs dropped.
- Added a new unreg_all() callback to event_command, and code to
call it when the trigger file is opened for truncate. Implemented
unreg_all() for hist triggers, which allows them to honor the
truncate flag while leaving existing triggers intact. This means
that '>>' should now be used for adding multiple hist triggers as
well as to clear/pause/cont an existing hist trigger.
- Included Namhyung's log2 patch.
- Fixed one of Masami's test cases which now requires using '>>' due
to the truncate changes.
- 'cont' and 'clear' no longer create a trigger if one doesn't exist.
- Rebased to latest trace/for-next.
- Various other smaller fixes and Documentation updates as noted by
Namhyung.
Changes from v10:
- Rebased to latest trace/for-next.
- Added Masami's ftrace/hist triggers kselftest patches.
- Added Masami's Tested-by: to the series.
Changes from v9:
v10 adds some major new features - 'named' hist triggers and support
for multiple hist triggers on a single event - basically all of the
features and suggestions suggested by Masami, except for one: I
decided after all not to implement the 'pause/continue/clear' commands
on the hist file. I've gotten so used to the habit of calling up the
previous trigger-setting command in the command history and simply
appending a 'pause/cont/clear' command to it (and later removing it by
prepending a '!') that making the user change the command doesn't seem
as naturally usable. Masami, if you disagree, let me know and I'll
reconsider it but at this point I'd rather not make that change.
In addition, I think I've fixed all the other various smaller problems
mentioned in the previous review, please let me know if I missed any...
- Added support for 'named' hist triggers
- Added support for multiple hist triggers on a single trace event
- Added documentation and examples for the above new features
- Streamlined the README to only include the essentials for hist triggers
- Fixed the 'hex' modifier for values, which was previously ignored
- Replaced the kmalloc of large arrays with a simple page-based scheme
- Fixed the tracing_map_insert() case where jhash returns 0
- Fixed various other small problems noted along the way
Changes from v8:
Same as v8, but with the RFC patch [ftrace: Add function_hist tracer]
removed, and rebased to latest trace/for-next.
Changes from v7:
This version refactors the commits as suggested by Masami. There are
now more commits, but the result should be much more reviewable. The
ending code is the same as before, modulo a couple minor bug fixes I
discovered while refactoring and testing.
I've also reviewed and fixed a number of shortcomings and errors in
the comments, and have added a new discussion of the tracing_map data
structures after Steve mentioned he found them confusing and/or
insufficiently documented.
Also, I kept Namhyung's string patch [tracing: Support string type key
properly] as submitted, but added a follow-on patch that refactors it
and fixes a problem I found with it that enabled static string keys to
contain random chars and therefore incorrect map insertions.
Changes from v6:
This version adds a new 'sym-offset' modifier as requested by Masami.
I implemented it as a modifier rather than using the trace option as
suggested, in part because I wanted to keep it all self-contained and
it seemed more consistent to just add it alongside the 'sym' modifier.
Also, hist triggers arent't really a tracer and therefore don't
directly tie into the option update/callback mechanism so making use
of it isn't as simple as a normal tracer.
I also changed the sort key specification to be stricter and signal an
error if the specified sort key wasn't found (rather than defaulting
to hitcount in those cases), also suggested by Masami. Thanks,
Masami, for your input!
Also updated the Documentation and tracing/README to reflect the
changes.
Changes from v5:
This version adds support for compound keys, along with the related
ability to sort using primary and secondary keys. This was mentioned
in previous versions as the last important piece that remained
unimplemented, and is now implemented. (I didn't have time to get to
the couple of enhancements suggested by Masami, but I expect to be
able to add those later on top of these.)
Because we now support compound keys and it's not immediately clear in
the output exactly which fields correspond to keys, the key(s),
compound or not, are now enclosed by curly braces.
The Documentation and README have been updated to reflect the changes,
and several new examples have been added to illustrate how to use
compound keys.
Also, the code was updated to work with the new ftrace_event_file,
etc, renaming in tracing/for-next.
Changes from v4:
This version addresses some problems and suggestions made by Daniel
Wagner - a lot of the code was reworked to get rid of the distinction
between keys and values, and as a result, both keys and values can be
used as sort keys. As suggested, it also allows 'val=' to be absent
in a trigger command - if no 'val' is specified, hitcount is assumed
and automatically used as the only val.
The map code was also separated out into a separate file,
tracing_map.c, allowing it to be reused. It also adds a second tracer
called function_hist that actually does reuse the code, as an RFC
patch.
Patch 01/10 [tracing: Update cond flag when enabling or disabling..]
is a fix for a problem noticed by Daniel and that fixes a problem in
existing trigger code and should be applied regardless of whether the
rest of the patchset is merged.
As mentioned, patch 10/10 is an RFC patch implementing a new tracer
based on the function tracer code. It's a fun little tool and is
useful for a specific problem I'm working on (and is also a nice test
of the tracing_map code), but is an RFC because first, I'm not sure it
would really be of general interest and secondly, it's POC-level
quality and I'd need to spend more time fixing it up to make it
upstreamable, but I don't want to waste my time if not.
There are a couple of important bits of functionality that were
present in v1 but not yet reimplemented in v5.
The first is support for compound keys. Currently, maps can only be
keyed on a single event field, whereas in v1 they could be keyed on
multiple keys. With support for compound keys, you can create much
more interesting output, such as for example per-pid lists of
syscalls or read counts e.g.:
# echo 'hist:keys=common_pid.execname,id.syscall:vals=hitcount' > \
/sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
# cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
key: common_pid:bash[3112], id:sys_write vals: count:69
key: common_pid:bash[3112], id:sys_rt_sigprocmask vals: count:218
key: common_pid:update-notifier[3164], id:sys_poll vals: count:37
key: common_pid:update-notifier[3164], id:sys_recvfrom vals: count:118
key: common_pid:deja-dup-monito[3194], id:sys_sendto vals: count:1
key: common_pid:deja-dup-monito[3194], id:sys_read vals: count:4
key: common_pid:deja-dup-monito[3194], id:sys_poll vals: count:8
key: common_pid:deja-dup-monito[3194], id:sys_recvmsg vals: count:8
key: common_pid:deja-dup-monito[3194], id:sys_getegid vals: count:8
key: common_pid:emacs[3275], id:sys_fsync vals: count:1
key: common_pid:emacs[3275], id:sys_open vals: count:1
key: common_pid:emacs[3275], id:sys_symlink vals: count:2
key: common_pid:emacs[3275], id:sys_poll vals: count:23
key: common_pid:emacs[3275], id:sys_select vals: count:23
key: common_pid:emacs[3275], id:unknown_syscall vals: count:34
key: common_pid:emacs[3275], id:sys_ioctl vals: count:60
key: common_pid:emacs[3275], id:sys_rt_sigprocmask vals: count:116
key: common_pid:cat[3323], id:sys_munmap vals: count:1
key: common_pid:cat[3323], id:sys_fadvise64 vals: count:1
Related to that is support for sorting on multiple fields. Currently,
you can sort using only a primary key. Being able to sort on multiple
or at least a secondary key is indispensible for seeing trends when
displaying multiple values.
Changes from v3:
v4 fixes the race in tracing_map_insert() noted in v3, where
map.val.key could be checked even if map.val wasn't yet set. The
simple fix for that in tracing_map_insert() introduces the possibility
of duplicates in the map, which though rare, need to be accounted for
in the output. To address that, duplicate-merging code was added to
the map-printing code.
It was also pointed out that it didn't seem correct to include
module.h, but the fix for that has deeper roots and is being addressed
by a separate patchset; for now we need to continue including
module.h, though prompted by that I did some other header include
cleanup.
The functionality remains the same as v2, but this version no longer
tries to export and use bpf_maps, and more importantly removes the
associated GFP_NOTRACE/trace event hacks and kmem macros required to
work around the bpf_map implementation.
The tracing_map functionality is instead built on top of a simple
lock-free map algorithm originated by Dr. Cliff Click (see references
in the code for more details), which though too restrictive to be
general-purpose in its current form, functions nicely as a
special-purpose tracing map.
v3 also moves the hist triggers code into a separate file and puts it
all behind a new config option, CONFIG_HIST_TRIGGERS. It also merges
in the sorting code rather than keeping it as a separate patch.
This patchset also includes a couple other new and related triggers,
enable_hist and disable_hist, very similar to the existing
enable_event/disable_event triggers used to automatically enable and
disable events based on a triggering condition, but in this case
allowing hist triggers to be enabled and disabled in the same way.
- Added an insert check for val before checking the key associated with val
- Added code to merge possible duplicates in the map
Changes from v2:
- reimplemented tracing_map, replacing bpf_map with nmi-safe/lock-free map
- removed GPF_NOTRACE, kmalloc/free macros and event hacks needed by bpf_maps
- moved hist triggers from trace_events_trigger.c to trace_events_hist.c
- added CONFIG_HIST_TRIGGERS config option
- consolidated sorting code with main patch
Changes from v1:
- completely rewritten on top of tracing_map (renamed and exported bpf_map)
- added map clearing and client ops to tracing_map
- changed the name from 'hash' triggers to 'hist' triggers
- added new trigger 'pause' feature
- added new enable_hist and disable_hist triggers
- added usage for hist/enable_hist/disable hist to tracing/README
- moved examples into Documentation/trace/event.txt
- added ___GFP_NOTRACE, kmalloc/kfree macros, and conditional kmem tracepoints
The following changes since commit c230d332a81237cfef69ebc6060cf597889ede77:
tracing: Add lock-free tracing_map (2016-02-20 17:12:59 -0600)
are available in the git repository at:
git://git.yoctoproject.org/linux-yocto-contrib.git tzanussi/hist-triggers-v15
http://git.yoctoproject.org/cgit/cgit.cgi/linux-yocto-contrib/log/?h=tzanussi/hist-triggers-v15
Masami Hiramatsu (3):
kselftests/ftrace : Add event trigger testcases
kselftests/ftrace: Add hist trigger testcases
kselftests/ftrace: Add a test for log2 modifier of hist trigger
Namhyung Kim (2):
tracing: Support string type key properly
tracing: Add hist trigger 'log2' modifier
Tom Zanussi (18):
tracing: Update some tracing_map constants and comments
tracing: Add 'hist' event trigger command
tracing: Add hist trigger support for multiple values ('vals=' param)
tracing: Add hist trigger support for compound keys
tracing: Add hist trigger support for user-defined sorting ('sort='
param)
tracing: Add hist trigger support for pausing and continuing a trace
tracing: Add hist trigger support for clearing a trace
tracing: Add hist trigger 'hex' modifier for displaying numeric fields
tracing: Add hist trigger 'sym' and 'sym-offset' modifiers
tracing: Add hist trigger 'execname' modifier
tracing: Add hist trigger 'syscall' modifier
tracing: Add hist trigger support for stacktraces as keys
tracing: Remove restriction on string position in hist trigger keys
tracing: Add enable_hist/disable_hist triggers
tracing: Add 'hist' trigger Documentation
tracing: Add support for multiple hist triggers per event
tracing: Add support for named triggers
tracing: Add support for named hist triggers
Documentation/trace/events.txt | 1555 +++++++++++++++++
include/linux/trace_events.h | 2 +
kernel/trace/Kconfig | 14 +
kernel/trace/Makefile | 1 +
kernel/trace/trace.c | 57 +
kernel/trace/trace.h | 52 +
kernel/trace/trace_events.c | 4 +
kernel/trace/trace_events_hist.c | 1746 ++++++++++++++++++++
kernel/trace/trace_events_trigger.c | 215 ++-
kernel/trace/tracing_map.c | 4 +-
kernel/trace/tracing_map.h | 5 +-
tools/testing/selftests/ftrace/test.d/functions | 9 +
.../ftrace/test.d/trigger/trigger-eventonoff.tc | 64 +
.../ftrace/test.d/trigger/trigger-filter.tc | 59 +
.../ftrace/test.d/trigger/trigger-hist-mod.tc | 75 +
.../ftrace/test.d/trigger/trigger-hist.tc | 83 +
.../ftrace/test.d/trigger/trigger-multihist.tc | 73 +
.../ftrace/test.d/trigger/trigger-snapshot.tc | 56 +
.../ftrace/test.d/trigger/trigger-stacktrace.tc | 53 +
.../ftrace/test.d/trigger/trigger-traceonoff.tc | 58 +
20 files changed, 4150 insertions(+), 35 deletions(-)
create mode 100644 kernel/trace/trace_events_hist.c
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-eventonoff.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-filter.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-hist.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-snapshot.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-stacktrace.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-traceonoff.tc
--
1.9.3
^ permalink raw reply [flat|nested] 28+ messages in thread
* [PATCH v15 01/23] tracing: Update some tracing_map constants and comments
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 02/23] tracing: Add 'hist' event trigger command Tom Zanussi
` (21 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Make it clear exactly how many keys and values are supported through
better defines, and add 1 to the vals count, since normally clients
want support for at least a hitcount and two other values.
Also, note the error return value for tracing_map_add_key/val_field()
in the comments.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
kernel/trace/tracing_map.c | 4 ++--
kernel/trace/tracing_map.h | 5 +++--
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c
index dd6401d..e0f1729 100644
--- a/kernel/trace/tracing_map.c
+++ b/kernel/trace/tracing_map.c
@@ -163,7 +163,7 @@ static int tracing_map_add_field(struct tracing_map *map,
* tracing_map_update_sum() or reading it via tracing_map_read_sum().
*
* Return: The index identifying the field in the map and associated
- * tracing_map_elts.
+ * tracing_map_elts, or -EINVAL on error.
*/
int tracing_map_add_sum_field(struct tracing_map *map)
{
@@ -184,7 +184,7 @@ int tracing_map_add_sum_field(struct tracing_map *map)
* the key referenced by this key field resides.
*
* Return: The index identifying the field in the map and associated
- * tracing_map_elts.
+ * tracing_map_elts, or -EINVAL on error.
*/
int tracing_map_add_key_field(struct tracing_map *map,
unsigned int offset,
diff --git a/kernel/trace/tracing_map.h b/kernel/trace/tracing_map.h
index 7571825..b575d0b 100644
--- a/kernel/trace/tracing_map.h
+++ b/kernel/trace/tracing_map.h
@@ -5,9 +5,10 @@
#define TRACING_MAP_BITS_MAX 17
#define TRACING_MAP_BITS_MIN 7
-#define TRACING_MAP_FIELDS_MAX 4
#define TRACING_MAP_KEYS_MAX 2
-
+#define TRACING_MAP_VALS_MAX 3
+#define TRACING_MAP_FIELDS_MAX (TRACING_MAP_KEYS_MAX + \
+ TRACING_MAP_VALS_MAX)
#define TRACING_MAP_SORT_KEYS_MAX 2
typedef int (*tracing_map_cmp_fn_t) (void *val_a, void *val_b);
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 02/23] tracing: Add 'hist' event trigger command
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 01/23] tracing: Update some tracing_map constants and comments Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-03-02 14:33 ` Steven Rostedt
2016-02-26 16:01 ` [PATCH v15 03/23] tracing: Add hist trigger support for multiple values ('vals=' param) Tom Zanussi
` (20 subsequent siblings)
22 siblings, 1 reply; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
'hist' triggers allow users to continually aggregate trace events,
which can then be viewed afterwards by simply reading a 'hist' file
containing the aggregation in a human-readable format.
The basic idea is very simple and boils down to a mechanism whereby
trace events, rather than being exhaustively dumped in raw form and
viewed directly, are automatically 'compressed' into meaningful tables
completely defined by the user.
This is done strictly via single-line command-line commands and
without the aid of any kind of programming language or interpreter.
A surprising number of typical use cases can be accomplished by users
via this simple mechanism. In fact, a large number of the tasks that
users typically do using the more complicated script-based tracing
tools, at least during the initial stages of an investigation, can be
accomplished by simply specifying a set of keys and values to be used
in the creation of a hash table.
The Linux kernel trace event subsystem happens to provide an extensive
list of keys and values ready-made for such a purpose in the form of
the event format files associated with each trace event. By simply
consulting the format file for field names of interest and by plugging
them into the hist trigger command, users can create an endless number
of useful aggregations to help with investigating various properties
of the system. See Documentation/trace/events.txt for examples.
hist triggers are implemented on top of the existing event trigger
infrastructure, and as such are consistent with the existing triggers
from a user's perspective as well.
The basic syntax follows the existing trigger syntax. Users start an
aggregation by writing a 'hist' trigger to the event of interest's
trigger file:
# echo hist:keys=xxx [ if filter] > event/trigger
Once a hist trigger has been set up, by default it continually
aggregates every matching event into a hash table using the event key
and a value field named 'hitcount'.
To view the aggregation at any point in time, simply read the 'hist'
file in the same directory as the 'trigger' file:
# cat event/hist
The detailed syntax provides additional options for user control, and
is described exhaustively in Documentation/trace/events.txt and in the
virtual tracing/README file in the tracing subsystem.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
include/linux/trace_events.h | 1 +
kernel/trace/Kconfig | 14 +
kernel/trace/Makefile | 1 +
kernel/trace/trace.c | 17 +
kernel/trace/trace.h | 7 +
kernel/trace/trace_events.c | 4 +
kernel/trace/trace_events_hist.c | 845 ++++++++++++++++++++++++++++++++++++
kernel/trace/trace_events_trigger.c | 1 +
8 files changed, 890 insertions(+)
create mode 100644 kernel/trace/trace_events_hist.c
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 95e8fef..e61816d 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -417,6 +417,7 @@ enum event_trigger_type {
ETT_SNAPSHOT = (1 << 1),
ETT_STACKTRACE = (1 << 2),
ETT_EVENT_ENABLE = (1 << 3),
+ ETT_EVENT_HIST = (1 << 4),
};
extern int filter_match_preds(struct event_filter *filter, void *rec);
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 48b7329..a2e6b83 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -539,6 +539,20 @@ config TRACING_MAP
generally used outside of that context, and is normally
selected by tracers that use it.
+config HIST_TRIGGERS
+ bool "Histogram triggers"
+ depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
+ select TRACING_MAP
+ default n
+ help
+ Hist triggers allow one or more arbitrary trace event fields
+ to be aggregated into hash tables and dumped to stdout by
+ reading a debugfs/tracefs file. They're useful for
+ gathering quick and dirty (though precise) summaries of
+ event activity as an initial guide for further investigation
+ using more advanced tools.
+
+ See Documentation/trace/events.txt.
If in doubt, say N.
config MMIOTRACE_TEST
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 4255c40..979e7bf 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -54,6 +54,7 @@ obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o
endif
obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o
+obj-$(CONFIG_HIST_TRIGGERS) += trace_events_hist.o
obj-$(CONFIG_BPF_EVENTS) += bpf_trace.o
obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o
obj-$(CONFIG_TRACEPOINTS) += power-traces.o
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d929340..7140e2e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3804,6 +3804,9 @@ static const char readme_msg[] =
#ifdef CONFIG_TRACER_SNAPSHOT
"\t\t snapshot\n"
#endif
+#ifdef CONFIG_HIST_TRIGGERS
+ "\t\t hist (see below)\n"
+#endif
"\t example: echo traceoff > events/block/block_unplug/trigger\n"
"\t echo traceoff:3 > events/block/block_unplug/trigger\n"
"\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n"
@@ -3819,6 +3822,20 @@ static const char readme_msg[] =
"\t To remove a trigger with a count:\n"
"\t echo '!<trigger>:0 > <system>/<event>/trigger\n"
"\t Filters can be ignored when removing a trigger.\n"
+#ifdef CONFIG_HIST_TRIGGERS
+ " hist trigger\t- If set, event hits are aggregated into a hash table\n"
+ "\t Format: hist:keys=<field1>\n"
+ "\t [:size=#entries]\n"
+ "\t [if <filter>]\n\n"
+ "\t When a matching event is hit, an entry is added to a hash\n"
+ "\t table using the key named, and the value of a sum called\n"
+ "\t 'hitcount' is incremented. Keys correspond to fields in the\n"
+ "\t event's format description. Keys can be any field. The\n"
+ "\t 'size' parameter can be used to specify more or fewer than\n"
+ "\t the default 2048 entries for the hashtable size.\n\n"
+ "\t Reading the 'hist' file for the event will dump the hash\n"
+ "\t table in its entirety to stdout."
+#endif
;
static ssize_t
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index d5d0dbe..bd04013 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1161,6 +1161,13 @@ extern struct mutex event_mutex;
extern struct list_head ftrace_events;
extern const struct file_operations event_trigger_fops;
+extern const struct file_operations event_hist_fops;
+
+#ifdef CONFIG_HIST_TRIGGERS
+extern int register_trigger_hist_cmd(void);
+#else
+static inline int register_trigger_hist_cmd(void) { return 0; }
+#endif
extern int register_trigger_cmds(void);
extern void clear_event_triggers(struct trace_array *tr);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 4f6ef69..8b54f21 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2107,6 +2107,10 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file)
trace_create_file("trigger", 0644, file->dir, file,
&event_trigger_fops);
+#ifdef CONFIG_HIST_TRIGGERS
+ trace_create_file("hist", 0444, file->dir, file,
+ &event_hist_fops);
+#endif
trace_create_file("format", 0444, file->dir, call,
&ftrace_event_format_fops);
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
new file mode 100644
index 0000000..6ac881f
--- /dev/null
+++ b/kernel/trace/trace_events_hist.c
@@ -0,0 +1,845 @@
+/*
+ * trace_events_hist - trace event hist triggers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/stacktrace.h>
+
+#include "tracing_map.h"
+#include "trace.h"
+
+struct hist_field;
+
+typedef u64 (*hist_field_fn_t) (struct hist_field *field, void *event);
+
+struct hist_field {
+ struct ftrace_event_field *field;
+ unsigned long flags;
+ hist_field_fn_t fn;
+ unsigned int size;
+};
+
+static u64 hist_field_counter(struct hist_field *field, void *event)
+{
+ return 1;
+}
+
+static u64 hist_field_string(struct hist_field *hist_field, void *event)
+{
+ char *addr = (char *)(event + hist_field->field->offset);
+
+ return (u64)(unsigned long)addr;
+}
+
+#define DEFINE_HIST_FIELD_FN(type) \
+static u64 hist_field_##type(struct hist_field *hist_field, void *event)\
+{ \
+ type *addr = (type *)(event + hist_field->field->offset); \
+ \
+ return (u64)*addr; \
+}
+
+DEFINE_HIST_FIELD_FN(s64);
+DEFINE_HIST_FIELD_FN(u64);
+DEFINE_HIST_FIELD_FN(s32);
+DEFINE_HIST_FIELD_FN(u32);
+DEFINE_HIST_FIELD_FN(s16);
+DEFINE_HIST_FIELD_FN(u16);
+DEFINE_HIST_FIELD_FN(s8);
+DEFINE_HIST_FIELD_FN(u8);
+
+#define for_each_hist_field(i, hist_data) \
+ for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
+
+#define for_each_hist_val_field(i, hist_data) \
+ for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
+
+#define for_each_hist_key_field(i, hist_data) \
+ for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
+
+#define HITCOUNT_IDX 0
+#define HIST_KEY_MAX 1
+#define HIST_KEY_SIZE_MAX MAX_FILTER_STR_VAL
+
+enum hist_field_flags {
+ HIST_FIELD_FL_HITCOUNT = 1,
+ HIST_FIELD_FL_KEY = 2,
+ HIST_FIELD_FL_STRING = 4,
+};
+
+struct hist_trigger_attrs {
+ char *keys_str;
+ unsigned int map_bits;
+};
+
+struct hist_trigger_data {
+ struct hist_field *fields[TRACING_MAP_FIELDS_MAX];
+ unsigned int n_vals;
+ unsigned int n_keys;
+ unsigned int n_fields;
+ unsigned int key_size;
+ struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
+ unsigned int n_sort_keys;
+ struct trace_event_file *event_file;
+ struct hist_trigger_attrs *attrs;
+ struct tracing_map *map;
+};
+
+static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
+{
+ hist_field_fn_t fn = NULL;
+
+ switch (field_size) {
+ case 8:
+ if (field_is_signed)
+ fn = hist_field_s64;
+ else
+ fn = hist_field_u64;
+ break;
+ case 4:
+ if (field_is_signed)
+ fn = hist_field_s32;
+ else
+ fn = hist_field_u32;
+ break;
+ case 2:
+ if (field_is_signed)
+ fn = hist_field_s16;
+ else
+ fn = hist_field_u16;
+ break;
+ case 1:
+ if (field_is_signed)
+ fn = hist_field_s8;
+ else
+ fn = hist_field_u8;
+ break;
+ }
+
+ return fn;
+}
+
+static int parse_map_size(char *str)
+{
+ unsigned long size, map_bits;
+ int ret;
+
+ strsep(&str, "=");
+ if (!str) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = kstrtoul(str, 0, &size);
+ if (ret)
+ goto out;
+
+ map_bits = ilog2(roundup_pow_of_two(size));
+ if (map_bits < TRACING_MAP_BITS_MIN ||
+ map_bits > TRACING_MAP_BITS_MAX)
+ ret = -EINVAL;
+ else
+ ret = map_bits;
+ out:
+ return ret;
+}
+
+static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
+{
+ if (!attrs)
+ return;
+
+ kfree(attrs->keys_str);
+ kfree(attrs);
+}
+
+static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
+{
+ struct hist_trigger_attrs *attrs;
+ int ret = 0;
+
+ attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
+ if (!attrs)
+ return ERR_PTR(-ENOMEM);
+
+ while (trigger_str) {
+ char *str = strsep(&trigger_str, ":");
+
+ if ((strncmp(str, "key=", strlen("key=")) == 0) ||
+ (strncmp(str, "keys=", strlen("keys=")) == 0))
+ attrs->keys_str = kstrdup(str, GFP_KERNEL);
+ else if (strncmp(str, "size=", strlen("size=")) == 0) {
+ int map_bits = parse_map_size(str);
+
+ if (map_bits < 0) {
+ ret = map_bits;
+ goto free;
+ }
+ attrs->map_bits = map_bits;
+ } else {
+ ret = -EINVAL;
+ goto free;
+ }
+ }
+
+ if (!attrs->keys_str) {
+ ret = -EINVAL;
+ goto free;
+ }
+
+ return attrs;
+ free:
+ destroy_hist_trigger_attrs(attrs);
+
+ return ERR_PTR(ret);
+}
+
+static void destroy_hist_field(struct hist_field *hist_field)
+{
+ kfree(hist_field);
+}
+
+static struct hist_field *create_hist_field(struct ftrace_event_field *field,
+ unsigned long flags)
+{
+ struct hist_field *hist_field;
+
+ if (field && is_function_field(field))
+ return NULL;
+
+ hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
+ if (!hist_field)
+ return NULL;
+
+ if (flags & HIST_FIELD_FL_HITCOUNT) {
+ hist_field->fn = hist_field_counter;
+ goto out;
+ }
+
+ if (is_string_field(field)) {
+ flags |= HIST_FIELD_FL_STRING;
+ hist_field->fn = hist_field_string;
+ } else {
+ hist_field->fn = select_value_fn(field->size,
+ field->is_signed);
+ if (!hist_field->fn) {
+ destroy_hist_field(hist_field);
+ return NULL;
+ }
+ }
+ out:
+ hist_field->field = field;
+ hist_field->flags = flags;
+
+ return hist_field;
+}
+
+static void destroy_hist_fields(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < TRACING_MAP_FIELDS_MAX; i++) {
+ if (hist_data->fields[i]) {
+ destroy_hist_field(hist_data->fields[i]);
+ hist_data->fields[i] = NULL;
+ }
+ }
+}
+
+static int create_hitcount_val(struct hist_trigger_data *hist_data)
+{
+ hist_data->fields[HITCOUNT_IDX] =
+ create_hist_field(NULL, HIST_FIELD_FL_HITCOUNT);
+ if (!hist_data->fields[HITCOUNT_IDX])
+ return -ENOMEM;
+
+ if (WARN_ON(++hist_data->n_vals > TRACING_MAP_VALS_MAX))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int create_val_fields(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file)
+{
+ int ret;
+
+ ret = create_hitcount_val(hist_data);
+
+ return ret;
+}
+
+static int create_key_field(struct hist_trigger_data *hist_data,
+ unsigned int key_idx,
+ struct trace_event_file *file,
+ char *field_str)
+{
+ struct ftrace_event_field *field = NULL;
+ unsigned long flags = 0;
+ unsigned int key_size;
+ int ret = 0;
+
+ if (WARN_ON(key_idx >= TRACING_MAP_FIELDS_MAX))
+ return -EINVAL;
+
+ flags |= HIST_FIELD_FL_KEY;
+
+ field = trace_find_event_field(file->event_call, field_str);
+ if (!field) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ key_size = field->size;
+
+ hist_data->fields[key_idx] = create_hist_field(field, flags);
+ if (!hist_data->fields[key_idx]) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ key_size = ALIGN(key_size, sizeof(u64));
+ hist_data->fields[key_idx]->size = key_size;
+ hist_data->key_size = key_size;
+ if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (WARN_ON(++hist_data->n_keys > TRACING_MAP_KEYS_MAX))
+ return -EINVAL;
+
+ ret = key_size;
+ out:
+ return ret;
+}
+
+static int create_key_fields(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file)
+{
+ unsigned int i, n_vals = hist_data->n_vals;
+ char *fields_str, *field_str;
+ int ret = -EINVAL;
+
+ fields_str = hist_data->attrs->keys_str;
+ if (!fields_str)
+ goto out;
+
+ strsep(&fields_str, "=");
+ if (!fields_str)
+ goto out;
+
+ for (i = n_vals; i < n_vals + HIST_KEY_MAX; i++) {
+ field_str = strsep(&fields_str, ",");
+ if (!field_str)
+ break;
+ ret = create_key_field(hist_data, i, file, field_str);
+ if (ret < 0)
+ goto out;
+ }
+ if (fields_str) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = 0;
+ out:
+ return ret;
+}
+
+static int create_hist_fields(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file)
+{
+ int ret;
+
+ ret = create_val_fields(hist_data, file);
+ if (ret)
+ goto out;
+
+ ret = create_key_fields(hist_data, file);
+ if (ret)
+ goto out;
+
+ hist_data->n_fields = hist_data->n_vals + hist_data->n_keys;
+ out:
+ return ret;
+}
+
+static int create_sort_keys(struct hist_trigger_data *hist_data)
+{
+ int ret = 0;
+
+ hist_data->n_sort_keys = 1; /* sort_keys[0] is always hitcount */
+
+ return ret;
+}
+
+static void destroy_hist_data(struct hist_trigger_data *hist_data)
+{
+ destroy_hist_trigger_attrs(hist_data->attrs);
+ destroy_hist_fields(hist_data);
+ tracing_map_destroy(hist_data->map);
+ kfree(hist_data);
+}
+
+static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
+{
+ struct tracing_map *map = hist_data->map;
+ struct ftrace_event_field *field;
+ struct hist_field *hist_field;
+ unsigned int i, idx;
+
+ for_each_hist_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ if (hist_field->flags & HIST_FIELD_FL_KEY) {
+ tracing_map_cmp_fn_t cmp_fn;
+
+ field = hist_field->field;
+
+ if (is_string_field(field))
+ cmp_fn = tracing_map_cmp_string;
+ else
+ cmp_fn = tracing_map_cmp_num(field->size,
+ field->is_signed);
+ idx = tracing_map_add_key_field(map, 0, cmp_fn);
+ } else
+ idx = tracing_map_add_sum_field(map);
+
+ if (idx < 0)
+ return idx;
+ }
+
+ return 0;
+}
+
+static struct hist_trigger_data *
+create_hist_data(unsigned int map_bits,
+ struct hist_trigger_attrs *attrs,
+ struct trace_event_file *file)
+{
+ struct hist_trigger_data *hist_data;
+ int ret = 0;
+
+ hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
+ if (!hist_data)
+ return ERR_PTR(-ENOMEM);
+
+ hist_data->attrs = attrs;
+
+ ret = create_hist_fields(hist_data, file);
+ if (ret)
+ goto free;
+
+ ret = create_sort_keys(hist_data);
+ if (ret)
+ goto free;
+
+ hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
+ NULL, hist_data);
+ if (IS_ERR(hist_data->map)) {
+ ret = PTR_ERR(hist_data->map);
+ hist_data->map = NULL;
+ goto free;
+ }
+
+ ret = create_tracing_map_fields(hist_data);
+ if (ret)
+ goto free;
+
+ ret = tracing_map_init(hist_data->map);
+ if (ret)
+ goto free;
+
+ hist_data->event_file = file;
+ out:
+ return hist_data;
+ free:
+ hist_data->attrs = NULL;
+
+ destroy_hist_data(hist_data);
+
+ hist_data = ERR_PTR(ret);
+
+ goto out;
+}
+
+static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt,
+ void *rec)
+{
+ struct hist_field *hist_field;
+ unsigned int i;
+ u64 hist_val;
+
+ for_each_hist_val_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ hist_val = hist_field->fn(hist_field, rec);
+ tracing_map_update_sum(elt, i, hist_val);
+ }
+}
+
+static void event_hist_trigger(struct event_trigger_data *data, void *rec)
+{
+ struct hist_trigger_data *hist_data = data->private_data;
+ struct hist_field *key_field;
+ struct tracing_map_elt *elt;
+ u64 field_contents;
+ void *key = NULL;
+ unsigned int i;
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+
+ field_contents = key_field->fn(key_field, rec);
+ if (key_field->flags & HIST_FIELD_FL_STRING)
+ key = (void *)(unsigned long)field_contents;
+ else
+ key = (void *)&field_contents;
+ }
+
+ elt = tracing_map_insert(hist_data->map, key);
+ if (elt)
+ hist_trigger_elt_update(hist_data, elt, rec);
+}
+
+static void
+hist_trigger_entry_print(struct seq_file *m,
+ struct hist_trigger_data *hist_data, void *key,
+ struct tracing_map_elt *elt)
+{
+ struct hist_field *key_field;
+ unsigned int i;
+ u64 uval;
+
+ seq_puts(m, "{ ");
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+
+ if (i > hist_data->n_vals)
+ seq_puts(m, ", ");
+
+ if (key_field->flags & HIST_FIELD_FL_STRING) {
+ seq_printf(m, "%s: %-50s", key_field->field->name,
+ (char *)key);
+ } else {
+ uval = *(u64 *)key;
+ seq_printf(m, "%s: %10llu",
+ key_field->field->name, uval);
+ }
+ }
+
+ seq_puts(m, " }");
+
+ seq_printf(m, " hitcount: %10llu",
+ tracing_map_read_sum(elt, HITCOUNT_IDX));
+
+ seq_puts(m, "\n");
+}
+
+static int print_entries(struct seq_file *m,
+ struct hist_trigger_data *hist_data)
+{
+ struct tracing_map_sort_entry **sort_entries = NULL;
+ struct tracing_map *map = hist_data->map;
+ unsigned int i, n_entries;
+
+ n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
+ hist_data->n_sort_keys,
+ &sort_entries);
+ if (n_entries < 0)
+ return n_entries;
+
+ for (i = 0; i < n_entries; i++)
+ hist_trigger_entry_print(m, hist_data,
+ sort_entries[i]->key,
+ sort_entries[i]->elt);
+
+ tracing_map_destroy_sort_entries(sort_entries, n_entries);
+
+ return n_entries;
+}
+
+static int hist_show(struct seq_file *m, void *v)
+{
+ struct event_trigger_data *test, *data = NULL;
+ struct trace_event_file *event_file;
+ struct hist_trigger_data *hist_data;
+ int n_entries, ret = 0;
+
+ mutex_lock(&event_mutex);
+
+ event_file = event_file_data(m->private);
+ if (unlikely(!event_file)) {
+ ret = -ENODEV;
+ goto out_unlock;
+ }
+
+ list_for_each_entry_rcu(test, &event_file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ data = test;
+ break;
+ }
+ }
+ if (!data)
+ goto out_unlock;
+
+ seq_puts(m, "# event histogram\n#\n# trigger info: ");
+ data->ops->print(m, data->ops, data);
+ seq_puts(m, "\n");
+
+ hist_data = data->private_data;
+ n_entries = print_entries(m, hist_data);
+ if (n_entries < 0) {
+ ret = n_entries;
+ n_entries = 0;
+ }
+
+ seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
+ (u64)atomic64_read(&hist_data->map->hits),
+ n_entries, (u64)atomic64_read(&hist_data->map->drops));
+ out_unlock:
+ mutex_unlock(&event_mutex);
+
+ return ret;
+}
+
+static int event_hist_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, hist_show, file);
+}
+
+const struct file_operations event_hist_fops = {
+ .open = event_hist_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
+{
+ seq_printf(m, "%s", hist_field->field->name);
+}
+
+static int event_hist_trigger_print(struct seq_file *m,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
+{
+ struct hist_trigger_data *hist_data = data->private_data;
+ struct hist_field *key_field;
+ unsigned int i;
+
+ seq_puts(m, "hist:keys=");
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+
+ if (i > hist_data->n_vals)
+ seq_puts(m, ",");
+
+ hist_field_print(m, key_field);
+ }
+
+ seq_puts(m, ":vals=");
+ seq_puts(m, "hitcount");
+
+ seq_puts(m, ":sort=");
+ seq_puts(m, "hitcount");
+
+ seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
+
+ if (data->filter_str)
+ seq_printf(m, " if %s", data->filter_str);
+
+ seq_puts(m, " [active]");
+
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
+static void event_hist_trigger_free(struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
+{
+ struct hist_trigger_data *hist_data = data->private_data;
+
+ if (WARN_ON_ONCE(data->ref <= 0))
+ return;
+
+ data->ref--;
+ if (!data->ref) {
+ trigger_data_free(data);
+ destroy_hist_data(hist_data);
+ }
+}
+
+static struct event_trigger_ops event_hist_trigger_ops = {
+ .func = event_hist_trigger,
+ .print = event_hist_trigger_print,
+ .init = event_trigger_init,
+ .free = event_hist_trigger_free,
+};
+
+static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
+ char *param)
+{
+ return &event_hist_trigger_ops;
+}
+
+static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
+ struct event_trigger_data *data,
+ struct trace_event_file *file)
+{
+ struct event_trigger_data *test;
+ int ret = 0;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ ret = -EEXIST;
+ goto out;
+ }
+ }
+
+ if (data->ops->init) {
+ ret = data->ops->init(data->ops, data);
+ if (ret < 0)
+ goto out;
+ }
+
+ list_add_rcu(&data->list, &file->triggers);
+ ret++;
+
+ update_cond_flag(file);
+ if (trace_event_trigger_enable_disable(file, 1) < 0) {
+ list_del_rcu(&data->list);
+ update_cond_flag(file);
+ ret--;
+ }
+ out:
+ return ret;
+}
+
+static int event_hist_trigger_func(struct event_command *cmd_ops,
+ struct trace_event_file *file,
+ char *glob, char *cmd, char *param)
+{
+ unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
+ struct event_trigger_data *trigger_data;
+ struct hist_trigger_attrs *attrs;
+ struct event_trigger_ops *trigger_ops;
+ struct hist_trigger_data *hist_data;
+ char *trigger;
+ int ret = 0;
+
+ if (!param)
+ return -EINVAL;
+
+ /* separate the trigger from the filter (k:v [if filter]) */
+ trigger = strsep(¶m, " \t");
+ if (!trigger)
+ return -EINVAL;
+
+ attrs = parse_hist_trigger_attrs(trigger);
+ if (IS_ERR(attrs))
+ return PTR_ERR(attrs);
+
+ if (attrs->map_bits)
+ hist_trigger_bits = attrs->map_bits;
+
+ hist_data = create_hist_data(hist_trigger_bits, attrs, file);
+ if (IS_ERR(hist_data)) {
+ destroy_hist_trigger_attrs(attrs);
+ return PTR_ERR(hist_data);
+ }
+
+ trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
+
+ ret = -ENOMEM;
+ trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
+ if (!trigger_data)
+ goto out_free;
+
+ trigger_data->count = -1;
+ trigger_data->ops = trigger_ops;
+ trigger_data->cmd_ops = cmd_ops;
+
+ INIT_LIST_HEAD(&trigger_data->list);
+ RCU_INIT_POINTER(trigger_data->filter, NULL);
+
+ trigger_data->private_data = hist_data;
+
+ if (glob[0] == '!') {
+ cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
+ ret = 0;
+ goto out_free;
+ }
+
+ if (!param) /* if param is non-empty, it's supposed to be a filter */
+ goto out_reg;
+
+ if (!cmd_ops->set_filter)
+ goto out_reg;
+
+ ret = cmd_ops->set_filter(param, trigger_data, file);
+ if (ret < 0)
+ goto out_free;
+ out_reg:
+ ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
+ /*
+ * The above returns on success the # of triggers registered,
+ * but if it didn't register any it returns zero. Consider no
+ * triggers registered a failure too.
+ */
+ if (!ret) {
+ ret = -ENOENT;
+ goto out_free;
+ } else if (ret < 0)
+ goto out_free;
+ /* Just return zero, not the number of registered triggers */
+ ret = 0;
+ out:
+ return ret;
+ out_free:
+ if (cmd_ops->set_filter)
+ cmd_ops->set_filter(NULL, trigger_data, NULL);
+
+ kfree(trigger_data);
+
+ destroy_hist_data(hist_data);
+ goto out;
+}
+
+static struct event_command trigger_hist_cmd = {
+ .name = "hist",
+ .trigger_type = ETT_EVENT_HIST,
+ .flags = EVENT_CMD_FL_NEEDS_REC,
+ .func = event_hist_trigger_func,
+ .reg = hist_register_trigger,
+ .unreg = unregister_trigger,
+ .get_trigger_ops = event_hist_get_trigger_ops,
+ .set_filter = set_trigger_filter,
+};
+
+__init int register_trigger_hist_cmd(void)
+{
+ int ret;
+
+ ret = register_event_command(&trigger_hist_cmd);
+ WARN_ON(ret < 0);
+
+ return ret;
+}
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 38d362e..7e080a4 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -1450,6 +1450,7 @@ __init int register_trigger_cmds(void)
register_trigger_snapshot_cmd();
register_trigger_stacktrace_cmd();
register_trigger_enable_disable_cmds();
+ register_trigger_hist_cmd();
return 0;
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 03/23] tracing: Add hist trigger support for multiple values ('vals=' param)
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 01/23] tracing: Update some tracing_map constants and comments Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 02/23] tracing: Add 'hist' event trigger command Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-03-02 14:38 ` Steven Rostedt
2016-02-26 16:01 ` [PATCH v15 04/23] tracing: Add hist trigger support for compound keys Tom Zanussi
` (19 subsequent siblings)
22 siblings, 1 reply; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to specify trace event fields to use in aggregated sums
via a new 'vals=' keyword. Before this addition, the only aggregated
sum supported was the implied value 'hitcount'. With this addition,
'hitcount' is also supported as an explicit value field, as is any
numeric trace event field.
This expands the hist trigger syntax from this:
# echo hist:keys=xxx [ if filter] > event/trigger
to this:
# echo hist:keys=xxx:vals=yyy [ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 12 ++++---
kernel/trace/trace_events_hist.c | 77 +++++++++++++++++++++++++++++++++++++++-
2 files changed, 83 insertions(+), 6 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7140e2e..86cd8e6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3825,14 +3825,16 @@ static const char readme_msg[] =
#ifdef CONFIG_HIST_TRIGGERS
" hist trigger\t- If set, event hits are aggregated into a hash table\n"
"\t Format: hist:keys=<field1>\n"
+ "\t [:values=<field1[,field2,...]>]\n"
"\t [:size=#entries]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
- "\t table using the key named, and the value of a sum called\n"
- "\t 'hitcount' is incremented. Keys correspond to fields in the\n"
- "\t event's format description. Keys can be any field. The\n"
- "\t 'size' parameter can be used to specify more or fewer than\n"
- "\t the default 2048 entries for the hashtable size.\n\n"
+ "\t table using the key(s) and value(s) named, and the value of a\n"
+ "\t sum called 'hitcount' is incremented. Keys and values\n"
+ "\t correspond to fields in the event's format description. Keys\n"
+ "\t can be any field. Values must correspond to numeric fields.\n"
+ "\t The 'size' parameter can be used to specify more or fewer\n"
+ "\t than the default 2048 entries for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
"\t table in its entirety to stdout."
#endif
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 6ac881f..55e363d 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -84,6 +84,7 @@ enum hist_field_flags {
struct hist_trigger_attrs {
char *keys_str;
+ char *vals_str;
unsigned int map_bits;
};
@@ -165,6 +166,7 @@ static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
return;
kfree(attrs->keys_str);
+ kfree(attrs->vals_str);
kfree(attrs);
}
@@ -183,6 +185,10 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
if ((strncmp(str, "key=", strlen("key=")) == 0) ||
(strncmp(str, "keys=", strlen("keys=")) == 0))
attrs->keys_str = kstrdup(str, GFP_KERNEL);
+ else if ((strncmp(str, "val=", strlen("val=")) == 0) ||
+ (strncmp(str, "vals=", strlen("vals=")) == 0) ||
+ (strncmp(str, "values=", strlen("values=")) == 0))
+ attrs->vals_str = kstrdup(str, GFP_KERNEL);
else if (strncmp(str, "size=", strlen("size=")) == 0) {
int map_bits = parse_map_size(str);
@@ -274,13 +280,68 @@ static int create_hitcount_val(struct hist_trigger_data *hist_data)
return 0;
}
+static int create_val_field(struct hist_trigger_data *hist_data,
+ unsigned int val_idx,
+ struct trace_event_file *file,
+ char *field_str)
+{
+ struct ftrace_event_field *field = NULL;
+ unsigned long flags = 0;
+ int ret = 0;
+
+ if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
+ return -EINVAL;
+ field = trace_find_event_field(file->event_call, field_str);
+ if (!field) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ hist_data->fields[val_idx] = create_hist_field(field, flags);
+ if (!hist_data->fields[val_idx]) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (WARN_ON(++hist_data->n_vals > TRACING_MAP_VALS_MAX))
+ ret = -EINVAL;
+ out:
+ return ret;
+}
+
static int create_val_fields(struct hist_trigger_data *hist_data,
struct trace_event_file *file)
{
+ char *fields_str, *field_str;
+ unsigned int i, j;
int ret;
ret = create_hitcount_val(hist_data);
+ if (ret)
+ goto out;
+
+ fields_str = hist_data->attrs->vals_str;
+ if (!fields_str)
+ goto out;
+
+ strsep(&fields_str, "=");
+ if (!fields_str)
+ goto out;
+ for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
+ j < TRACING_MAP_VALS_MAX; i++) {
+ field_str = strsep(&fields_str, ",");
+ if (!field_str)
+ break;
+ if (strcmp(field_str, "hitcount") == 0)
+ continue;
+ ret = create_val_field(hist_data, j++, file, field_str);
+ if (ret)
+ goto out;
+ }
+ if (fields_str && (strcmp(fields_str, "hitcount") != 0))
+ ret = -EINVAL;
+ out:
return ret;
}
@@ -548,6 +609,12 @@ hist_trigger_entry_print(struct seq_file *m,
seq_printf(m, " hitcount: %10llu",
tracing_map_read_sum(elt, HITCOUNT_IDX));
+ for (i = 1; i < hist_data->n_vals; i++) {
+ seq_printf(m, " %s: %10llu",
+ hist_data->fields[i]->field->name,
+ tracing_map_read_sum(elt, i));
+ }
+
seq_puts(m, "\n");
}
@@ -655,7 +722,15 @@ static int event_hist_trigger_print(struct seq_file *m,
}
seq_puts(m, ":vals=");
- seq_puts(m, "hitcount");
+
+ for_each_hist_val_field(i, hist_data) {
+ if (i == HITCOUNT_IDX)
+ seq_puts(m, "hitcount");
+ else {
+ seq_puts(m, ",");
+ hist_field_print(m, hist_data->fields[i]);
+ }
+ }
seq_puts(m, ":sort=");
seq_puts(m, "hitcount");
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 04/23] tracing: Add hist trigger support for compound keys
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (2 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 03/23] tracing: Add hist trigger support for multiple values ('vals=' param) Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 05/23] tracing: Add hist trigger support for user-defined sorting ('sort=' param) Tom Zanussi
` (18 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to specify multiple trace event fields to use in keys by
allowing multiple fields in the 'keys=' keyword. With this addition,
any unique combination of any of the fields named in the 'keys'
keyword will result in a new entry being added to the hash table.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 10 ++++++----
kernel/trace/trace_events_hist.c | 41 +++++++++++++++++++++++++++++-----------
2 files changed, 36 insertions(+), 15 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 86cd8e6..1a97671 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3824,7 +3824,7 @@ static const char readme_msg[] =
"\t Filters can be ignored when removing a trigger.\n"
#ifdef CONFIG_HIST_TRIGGERS
" hist trigger\t- If set, event hits are aggregated into a hash table\n"
- "\t Format: hist:keys=<field1>\n"
+ "\t Format: hist:keys=<field1[,field2,...]>\n"
"\t [:values=<field1[,field2,...]>]\n"
"\t [:size=#entries]\n"
"\t [if <filter>]\n\n"
@@ -3832,9 +3832,11 @@ static const char readme_msg[] =
"\t table using the key(s) and value(s) named, and the value of a\n"
"\t sum called 'hitcount' is incremented. Keys and values\n"
"\t correspond to fields in the event's format description. Keys\n"
- "\t can be any field. Values must correspond to numeric fields.\n"
- "\t The 'size' parameter can be used to specify more or fewer\n"
- "\t than the default 2048 entries for the hashtable size.\n\n"
+ "\t can be any field. Compound keys consisting of up to two\n"
+ "\t fields can be specified by the 'keys' keyword. Values must\n"
+ "\t correspond to numeric fields. The 'size' parameter can be\n"
+ "\t used to specify more or fewer than the default 2048 entries\n"
+ "\t for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
"\t table in its entirety to stdout."
#endif
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 55e363d..cbd72f0 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -32,6 +32,7 @@ struct hist_field {
unsigned long flags;
hist_field_fn_t fn;
unsigned int size;
+ unsigned int offset;
};
static u64 hist_field_counter(struct hist_field *field, void *event)
@@ -73,8 +74,7 @@ DEFINE_HIST_FIELD_FN(u8);
for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
#define HITCOUNT_IDX 0
-#define HIST_KEY_MAX 1
-#define HIST_KEY_SIZE_MAX MAX_FILTER_STR_VAL
+#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + sizeof(u64))
enum hist_field_flags {
HIST_FIELD_FL_HITCOUNT = 1,
@@ -347,6 +347,7 @@ static int create_val_fields(struct hist_trigger_data *hist_data,
static int create_key_field(struct hist_trigger_data *hist_data,
unsigned int key_idx,
+ unsigned int key_offset,
struct trace_event_file *file,
char *field_str)
{
@@ -376,7 +377,8 @@ static int create_key_field(struct hist_trigger_data *hist_data,
key_size = ALIGN(key_size, sizeof(u64));
hist_data->fields[key_idx]->size = key_size;
- hist_data->key_size = key_size;
+ hist_data->fields[key_idx]->offset = key_offset;
+ hist_data->key_size += key_size;
if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
ret = -EINVAL;
goto out;
@@ -393,7 +395,7 @@ static int create_key_field(struct hist_trigger_data *hist_data,
static int create_key_fields(struct hist_trigger_data *hist_data,
struct trace_event_file *file)
{
- unsigned int i, n_vals = hist_data->n_vals;
+ unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
char *fields_str, *field_str;
int ret = -EINVAL;
@@ -405,13 +407,15 @@ static int create_key_fields(struct hist_trigger_data *hist_data,
if (!fields_str)
goto out;
- for (i = n_vals; i < n_vals + HIST_KEY_MAX; i++) {
+ for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
field_str = strsep(&fields_str, ",");
if (!field_str)
break;
- ret = create_key_field(hist_data, i, file, field_str);
+ ret = create_key_field(hist_data, i, key_offset,
+ file, field_str);
if (ret < 0)
goto out;
+ key_offset += ret;
}
if (fields_str) {
ret = -EINVAL;
@@ -476,7 +480,10 @@ static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
else
cmp_fn = tracing_map_cmp_num(field->size,
field->is_signed);
- idx = tracing_map_add_key_field(map, 0, cmp_fn);
+ idx = tracing_map_add_key_field(map,
+ hist_field->offset,
+ cmp_fn);
+
} else
idx = tracing_map_add_sum_field(map);
@@ -556,12 +563,16 @@ static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
static void event_hist_trigger(struct event_trigger_data *data, void *rec)
{
struct hist_trigger_data *hist_data = data->private_data;
+ char compound_key[HIST_KEY_SIZE_MAX];
struct hist_field *key_field;
struct tracing_map_elt *elt;
u64 field_contents;
void *key = NULL;
unsigned int i;
+ if (hist_data->n_keys > 1)
+ memset(compound_key, 0, hist_data->key_size);
+
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
@@ -570,8 +581,16 @@ static void event_hist_trigger(struct event_trigger_data *data, void *rec)
key = (void *)(unsigned long)field_contents;
else
key = (void *)&field_contents;
+
+ if (hist_data->n_keys > 1) {
+ memcpy(compound_key + key_field->offset, key,
+ key_field->size);
+ }
}
+ if (hist_data->n_keys > 1)
+ key = compound_key;
+
elt = tracing_map_insert(hist_data->map, key);
if (elt)
hist_trigger_elt_update(hist_data, elt, rec);
@@ -596,11 +615,11 @@ hist_trigger_entry_print(struct seq_file *m,
if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
- (char *)key);
+ (char *)(key + key_field->offset));
} else {
- uval = *(u64 *)key;
- seq_printf(m, "%s: %10llu",
- key_field->field->name, uval);
+ uval = *(u64 *)(key + key_field->offset);
+ seq_printf(m, "%s: %10llu", key_field->field->name,
+ uval);
}
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 05/23] tracing: Add hist trigger support for user-defined sorting ('sort=' param)
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (3 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 04/23] tracing: Add hist trigger support for compound keys Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 06/23] tracing: Add hist trigger support for pausing and continuing a trace Tom Zanussi
` (17 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to specify keys and/or values to sort on. With this
addition, keys and values specified using the 'keys=' and 'vals='
keywords can be used to sort the hist trigger output via a new 'sort='
keyword. If multiple sort keys are specified, the output will be
sorted using the second key as a secondary sort key, etc. The default
sort order is ascending; if the user wants a different sort order,
'.descending' can be appended to the specific sort key. Before this
addition, output was always sorted by 'hitcount' in ascending order.
This expands the hist trigger syntax from this:
# echo hist:keys=xxx:vals=yyy \
[ if filter] > event/trigger
to this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 6 ++-
kernel/trace/trace_events_hist.c | 112 +++++++++++++++++++++++++++++++++++++--
2 files changed, 114 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1a97671..641ccae 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3826,6 +3826,7 @@ static const char readme_msg[] =
" hist trigger\t- If set, event hits are aggregated into a hash table\n"
"\t Format: hist:keys=<field1[,field2,...]>\n"
"\t [:values=<field1[,field2,...]>]\n"
+ "\t [:sort=<field1[,field2,...]>]\n"
"\t [:size=#entries]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
@@ -3834,7 +3835,10 @@ static const char readme_msg[] =
"\t correspond to fields in the event's format description. Keys\n"
"\t can be any field. Compound keys consisting of up to two\n"
"\t fields can be specified by the 'keys' keyword. Values must\n"
- "\t correspond to numeric fields. The 'size' parameter can be\n"
+ "\t correspond to numeric fields. Sort keys consisting of up to\n"
+ "\t two fields can be specified using the 'sort' keyword. The\n"
+ "\t sort direction can be modified by appending '.descending' or\n"
+ "\t '.ascending' to a sort field. The 'size' parameter can be\n"
"\t used to specify more or fewer than the default 2048 entries\n"
"\t for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index cbd72f0..42ceff0 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -85,6 +85,7 @@ enum hist_field_flags {
struct hist_trigger_attrs {
char *keys_str;
char *vals_str;
+ char *sort_key_str;
unsigned int map_bits;
};
@@ -165,6 +166,7 @@ static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
if (!attrs)
return;
+ kfree(attrs->sort_key_str);
kfree(attrs->keys_str);
kfree(attrs->vals_str);
kfree(attrs);
@@ -189,6 +191,8 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
(strncmp(str, "vals=", strlen("vals=")) == 0) ||
(strncmp(str, "values=", strlen("values=")) == 0))
attrs->vals_str = kstrdup(str, GFP_KERNEL);
+ else if (strncmp(str, "sort=", strlen("sort=")) == 0)
+ attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
else if (strncmp(str, "size=", strlen("size=")) == 0) {
int map_bits = parse_map_size(str);
@@ -444,12 +448,92 @@ static int create_hist_fields(struct hist_trigger_data *hist_data,
return ret;
}
+static int is_descending(const char *str)
+{
+ if (!str)
+ return 0;
+
+ if (strcmp(str, "descending") == 0)
+ return 1;
+
+ if (strcmp(str, "ascending") == 0)
+ return 0;
+
+ return -EINVAL;
+}
+
static int create_sort_keys(struct hist_trigger_data *hist_data)
{
- int ret = 0;
+ char *fields_str = hist_data->attrs->sort_key_str;
+ struct ftrace_event_field *field = NULL;
+ struct tracing_map_sort_key *sort_key;
+ int descending, ret = 0;
+ unsigned int i, j;
+
+ hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
+
+ if (!fields_str)
+ goto out;
+
+ strsep(&fields_str, "=");
+ if (!fields_str) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
+ char *field_str, *field_name;
+
+ sort_key = &hist_data->sort_keys[i];
+
+ field_str = strsep(&fields_str, ",");
+ if (!field_str) {
+ if (i == 0)
+ ret = -EINVAL;
+ break;
+ }
+
+ if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
+ ret = -EINVAL;
+ break;
+ }
- hist_data->n_sort_keys = 1; /* sort_keys[0] is always hitcount */
+ field_name = strsep(&field_str, ".");
+ if (!field_name) {
+ ret = -EINVAL;
+ break;
+ }
+
+ if (strcmp(field_name, "hitcount") == 0) {
+ descending = is_descending(field_str);
+ if (descending < 0) {
+ ret = descending;
+ break;
+ }
+ sort_key->descending = descending;
+ continue;
+ }
+ for (j = 1; j < hist_data->n_fields; j++) {
+ field = hist_data->fields[j]->field;
+ if (field && (strcmp(field_name, field->name) == 0)) {
+ sort_key->field_idx = j;
+ descending = is_descending(field_str);
+ if (descending < 0) {
+ ret = descending;
+ goto out;
+ }
+ sort_key->descending = descending;
+ break;
+ }
+ }
+ if (j == hist_data->n_fields) {
+ ret = -EINVAL;
+ break;
+ }
+ }
+ hist_data->n_sort_keys = i;
+ out:
return ret;
}
@@ -752,7 +836,29 @@ static int event_hist_trigger_print(struct seq_file *m,
}
seq_puts(m, ":sort=");
- seq_puts(m, "hitcount");
+
+ for (i = 0; i < hist_data->n_sort_keys; i++) {
+ struct tracing_map_sort_key *sort_key;
+
+ sort_key = &hist_data->sort_keys[i];
+
+ if (i > 0)
+ seq_puts(m, ",");
+
+ if (sort_key->field_idx == HITCOUNT_IDX)
+ seq_puts(m, "hitcount");
+ else {
+ unsigned int idx = sort_key->field_idx;
+
+ if (WARN_ON(idx >= TRACING_MAP_FIELDS_MAX))
+ return -EINVAL;
+
+ hist_field_print(m, hist_data->fields[idx]);
+ }
+
+ if (sort_key->descending)
+ seq_puts(m, ".descending");
+ }
seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 06/23] tracing: Add hist trigger support for pausing and continuing a trace
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (4 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 05/23] tracing: Add hist trigger support for user-defined sorting ('sort=' param) Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 07/23] tracing: Add hist trigger support for clearing " Tom Zanussi
` (16 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to append 'pause' or 'continue' to an existing trigger in
order to have it paused or to have a paused trace continue.
This expands the hist trigger syntax from this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending \
[ if filter] >> event/trigger
to this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause or cont \
[ if filter] >> event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 7 ++++++-
kernel/trace/trace_events_hist.c | 31 ++++++++++++++++++++++++++++---
2 files changed, 34 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 641ccae..b0aa92b 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3828,6 +3828,7 @@ static const char readme_msg[] =
"\t [:values=<field1[,field2,...]>]\n"
"\t [:sort=<field1[,field2,...]>]\n"
"\t [:size=#entries]\n"
+ "\t [:pause][:continue]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named, and the value of a\n"
@@ -3842,7 +3843,11 @@ static const char readme_msg[] =
"\t used to specify more or fewer than the default 2048 entries\n"
"\t for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
- "\t table in its entirety to stdout."
+ "\t table in its entirety to stdout.\n\n"
+ "\t The 'pause' parameter can be used to pause an existing hist\n"
+ "\t trigger or to start a hist trigger but not log any events\n"
+ "\t until told to do so. 'continue' can be used to start or\n"
+ "\t restart a paused hist trigger.\n\n"
#endif
;
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 42ceff0..d5fbebb 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -86,6 +86,8 @@ struct hist_trigger_attrs {
char *keys_str;
char *vals_str;
char *sort_key_str;
+ bool pause;
+ bool cont;
unsigned int map_bits;
};
@@ -193,6 +195,11 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
attrs->vals_str = kstrdup(str, GFP_KERNEL);
else if (strncmp(str, "sort=", strlen("sort=")) == 0)
attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
+ else if (strcmp(str, "pause") == 0)
+ attrs->pause = true;
+ else if ((strcmp(str, "cont") == 0) ||
+ (strcmp(str, "continue") == 0))
+ attrs->cont = true;
else if (strncmp(str, "size=", strlen("size=")) == 0) {
int map_bits = parse_map_size(str);
@@ -865,7 +872,10 @@ static int event_hist_trigger_print(struct seq_file *m,
if (data->filter_str)
seq_printf(m, " if %s", data->filter_str);
- seq_puts(m, " [active]");
+ if (data->paused)
+ seq_puts(m, " [paused]");
+ else
+ seq_puts(m, " [active]");
seq_putc(m, '\n');
@@ -904,16 +914,30 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
{
+ struct hist_trigger_data *hist_data = data->private_data;
struct event_trigger_data *test;
int ret = 0;
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
- ret = -EEXIST;
+ if (hist_data->attrs->pause)
+ test->paused = true;
+ else if (hist_data->attrs->cont)
+ test->paused = false;
+ else
+ ret = -EEXIST;
goto out;
}
}
+ if (hist_data->attrs->cont) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ if (hist_data->attrs->pause)
+ data->paused = true;
+
if (data->ops->init) {
ret = data->ops->init(data->ops, data);
if (ret < 0)
@@ -1005,7 +1029,8 @@ static int event_hist_trigger_func(struct event_command *cmd_ops,
* triggers registered a failure too.
*/
if (!ret) {
- ret = -ENOENT;
+ if (!(attrs->pause || attrs->cont))
+ ret = -ENOENT;
goto out_free;
} else if (ret < 0)
goto out_free;
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 07/23] tracing: Add hist trigger support for clearing a trace
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (5 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 06/23] tracing: Add hist trigger support for pausing and continuing a trace Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 08/23] tracing: Add hist trigger 'hex' modifier for displaying numeric fields Tom Zanussi
` (15 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to append 'clear' to an existing trigger in order to have
the hash table cleared.
This expands the hist trigger syntax from this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause/cont \
[ if filter] >> event/trigger
to this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause/cont/clear \
[ if filter] >> event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 5 ++++-
kernel/trace/trace_events_hist.c | 24 ++++++++++++++++++++++--
2 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index b0aa92b..9f0ab15 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3828,7 +3828,7 @@ static const char readme_msg[] =
"\t [:values=<field1[,field2,...]>]\n"
"\t [:sort=<field1[,field2,...]>]\n"
"\t [:size=#entries]\n"
- "\t [:pause][:continue]\n"
+ "\t [:pause][:continue][:clear]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named, and the value of a\n"
@@ -3848,6 +3848,9 @@ static const char readme_msg[] =
"\t trigger or to start a hist trigger but not log any events\n"
"\t until told to do so. 'continue' can be used to start or\n"
"\t restart a paused hist trigger.\n\n"
+ "\t The 'clear' parameter will clear the contents of a running\n"
+ "\t hist trigger and leave its current paused/active state\n"
+ "\t unchanged.\n\n"
#endif
;
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index d5fbebb..69cf3d9 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -88,6 +88,7 @@ struct hist_trigger_attrs {
char *sort_key_str;
bool pause;
bool cont;
+ bool clear;
unsigned int map_bits;
};
@@ -200,6 +201,8 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
else if ((strcmp(str, "cont") == 0) ||
(strcmp(str, "continue") == 0))
attrs->cont = true;
+ else if (strcmp(str, "clear") == 0)
+ attrs->clear = true;
else if (strncmp(str, "size=", strlen("size=")) == 0) {
int map_bits = parse_map_size(str);
@@ -910,6 +913,21 @@ static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
return &event_hist_trigger_ops;
}
+static void hist_clear(struct event_trigger_data *data)
+{
+ struct hist_trigger_data *hist_data = data->private_data;
+ bool paused;
+
+ paused = data->paused;
+ data->paused = true;
+
+ synchronize_sched();
+
+ tracing_map_clear(hist_data->map);
+
+ data->paused = paused;
+}
+
static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
@@ -924,13 +942,15 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
test->paused = true;
else if (hist_data->attrs->cont)
test->paused = false;
+ else if (hist_data->attrs->clear)
+ hist_clear(test);
else
ret = -EEXIST;
goto out;
}
}
- if (hist_data->attrs->cont) {
+ if (hist_data->attrs->cont || hist_data->attrs->clear) {
ret = -ENOENT;
goto out;
}
@@ -1029,7 +1049,7 @@ static int event_hist_trigger_func(struct event_command *cmd_ops,
* triggers registered a failure too.
*/
if (!ret) {
- if (!(attrs->pause || attrs->cont))
+ if (!(attrs->pause || attrs->cont || attrs->clear))
ret = -ENOENT;
goto out_free;
} else if (ret < 0)
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 08/23] tracing: Add hist trigger 'hex' modifier for displaying numeric fields
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (6 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 07/23] tracing: Add hist trigger support for clearing " Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 09/23] tracing: Add hist trigger 'sym' and 'sym-offset' modifiers Tom Zanussi
` (14 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to have numeric fields displayed as hex values in the
output by appending '.hex' to field names:
# echo hist:keys=aaa,bbb.hex:vals=ccc.hex ... \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 5 +++-
kernel/trace/trace_events_hist.c | 62 ++++++++++++++++++++++++++++++++++++----
2 files changed, 60 insertions(+), 7 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 9f0ab15..d6b4692 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3843,7 +3843,10 @@ static const char readme_msg[] =
"\t used to specify more or fewer than the default 2048 entries\n"
"\t for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
- "\t table in its entirety to stdout.\n\n"
+ "\t table in its entirety to stdout. The default format used to\n"
+ "\t display a given field can be modified by appending any of the\n"
+ "\t following modifiers to the field name, as applicable:\n\n"
+ "\t .hex display a number as a hex value\n\n"
"\t The 'pause' parameter can be used to pause an existing hist\n"
"\t trigger or to start a hist trigger but not log any events\n"
"\t until told to do so. 'continue' can be used to start or\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 69cf3d9..734cdce 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -80,6 +80,7 @@ enum hist_field_flags {
HIST_FIELD_FL_HITCOUNT = 1,
HIST_FIELD_FL_KEY = 2,
HIST_FIELD_FL_STRING = 4,
+ HIST_FIELD_FL_HEX = 8,
};
struct hist_trigger_attrs {
@@ -301,11 +302,23 @@ static int create_val_field(struct hist_trigger_data *hist_data,
{
struct ftrace_event_field *field = NULL;
unsigned long flags = 0;
+ char *field_name;
int ret = 0;
if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
return -EINVAL;
- field = trace_find_event_field(file->event_call, field_str);
+
+ field_name = strsep(&field_str, ".");
+ if (field_str) {
+ if (strcmp(field_str, "hex") == 0)
+ flags |= HIST_FIELD_FL_HEX;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ field = trace_find_event_field(file->event_call, field_name);
if (!field) {
ret = -EINVAL;
goto out;
@@ -368,6 +381,7 @@ static int create_key_field(struct hist_trigger_data *hist_data,
struct ftrace_event_field *field = NULL;
unsigned long flags = 0;
unsigned int key_size;
+ char *field_name;
int ret = 0;
if (WARN_ON(key_idx >= TRACING_MAP_FIELDS_MAX))
@@ -375,7 +389,17 @@ static int create_key_field(struct hist_trigger_data *hist_data,
flags |= HIST_FIELD_FL_KEY;
- field = trace_find_event_field(file->event_call, field_str);
+ field_name = strsep(&field_str, ".");
+ if (field_str) {
+ if (strcmp(field_str, "hex") == 0)
+ flags |= HIST_FIELD_FL_HEX;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ field = trace_find_event_field(file->event_call, field_name);
if (!field) {
ret = -EINVAL;
goto out;
@@ -707,7 +731,11 @@ hist_trigger_entry_print(struct seq_file *m,
if (i > hist_data->n_vals)
seq_puts(m, ", ");
- if (key_field->flags & HIST_FIELD_FL_STRING) {
+ if (key_field->flags & HIST_FIELD_FL_HEX) {
+ uval = *(u64 *)(key + key_field->offset);
+ seq_printf(m, "%s: %llx",
+ key_field->field->name, uval);
+ } else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
} else {
@@ -723,9 +751,15 @@ hist_trigger_entry_print(struct seq_file *m,
tracing_map_read_sum(elt, HITCOUNT_IDX));
for (i = 1; i < hist_data->n_vals; i++) {
- seq_printf(m, " %s: %10llu",
- hist_data->fields[i]->field->name,
- tracing_map_read_sum(elt, i));
+ if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
+ seq_printf(m, " %s: %10llx",
+ hist_data->fields[i]->field->name,
+ tracing_map_read_sum(elt, i));
+ } else {
+ seq_printf(m, " %s: %10llu",
+ hist_data->fields[i]->field->name,
+ tracing_map_read_sum(elt, i));
+ }
}
seq_puts(m, "\n");
@@ -810,9 +844,25 @@ const struct file_operations event_hist_fops = {
.release = single_release,
};
+static const char *get_hist_field_flags(struct hist_field *hist_field)
+{
+ const char *flags_str = NULL;
+
+ if (hist_field->flags & HIST_FIELD_FL_HEX)
+ flags_str = "hex";
+
+ return flags_str;
+}
+
static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
{
seq_printf(m, "%s", hist_field->field->name);
+ if (hist_field->flags) {
+ const char *flags_str = get_hist_field_flags(hist_field);
+
+ if (flags_str)
+ seq_printf(m, ".%s", flags_str);
+ }
}
static int event_hist_trigger_print(struct seq_file *m,
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 09/23] tracing: Add hist trigger 'sym' and 'sym-offset' modifiers
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (7 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 08/23] tracing: Add hist trigger 'hex' modifier for displaying numeric fields Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier Tom Zanussi
` (13 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to have address fields displayed as symbols in the output
by appending '.sym' or 'sym-offset' to field names:
# echo hist:keys=aaa.sym,bbb.sym-offset ... \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 4 +++-
kernel/trace/trace_events_hist.c | 29 +++++++++++++++++++++++++----
2 files changed, 28 insertions(+), 5 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d6b4692..202220c 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3846,7 +3846,9 @@ static const char readme_msg[] =
"\t table in its entirety to stdout. The default format used to\n"
"\t display a given field can be modified by appending any of the\n"
"\t following modifiers to the field name, as applicable:\n\n"
- "\t .hex display a number as a hex value\n\n"
+ "\t .hex display a number as a hex value\n"
+ "\t .sym display an address as a symbol\n"
+ "\t .sym-offset display an address as a symbol and offset\n\n"
"\t The 'pause' parameter can be used to pause an existing hist\n"
"\t trigger or to start a hist trigger but not log any events\n"
"\t until told to do so. 'continue' can be used to start or\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 734cdce..fd4de16 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -77,10 +77,12 @@ DEFINE_HIST_FIELD_FN(u8);
#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + sizeof(u64))
enum hist_field_flags {
- HIST_FIELD_FL_HITCOUNT = 1,
- HIST_FIELD_FL_KEY = 2,
- HIST_FIELD_FL_STRING = 4,
- HIST_FIELD_FL_HEX = 8,
+ HIST_FIELD_FL_HITCOUNT = 1,
+ HIST_FIELD_FL_KEY = 2,
+ HIST_FIELD_FL_STRING = 4,
+ HIST_FIELD_FL_HEX = 8,
+ HIST_FIELD_FL_SYM = 16,
+ HIST_FIELD_FL_SYM_OFFSET = 32,
};
struct hist_trigger_attrs {
@@ -393,6 +395,10 @@ static int create_key_field(struct hist_trigger_data *hist_data,
if (field_str) {
if (strcmp(field_str, "hex") == 0)
flags |= HIST_FIELD_FL_HEX;
+ else if (strcmp(field_str, "sym") == 0)
+ flags |= HIST_FIELD_FL_SYM;
+ else if (strcmp(field_str, "sym-offset") == 0)
+ flags |= HIST_FIELD_FL_SYM_OFFSET;
else {
ret = -EINVAL;
goto out;
@@ -720,6 +726,7 @@ hist_trigger_entry_print(struct seq_file *m,
struct tracing_map_elt *elt)
{
struct hist_field *key_field;
+ char str[KSYM_SYMBOL_LEN];
unsigned int i;
u64 uval;
@@ -735,6 +742,16 @@ hist_trigger_entry_print(struct seq_file *m,
uval = *(u64 *)(key + key_field->offset);
seq_printf(m, "%s: %llx",
key_field->field->name, uval);
+ } else if (key_field->flags & HIST_FIELD_FL_SYM) {
+ uval = *(u64 *)(key + key_field->offset);
+ sprint_symbol_no_offset(str, uval);
+ seq_printf(m, "%s: [%llx] %-45s",
+ key_field->field->name, uval, str);
+ } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
+ uval = *(u64 *)(key + key_field->offset);
+ sprint_symbol(str, uval);
+ seq_printf(m, "%s: [%llx] %-55s",
+ key_field->field->name, uval, str);
} else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
@@ -850,6 +867,10 @@ static const char *get_hist_field_flags(struct hist_field *hist_field)
if (hist_field->flags & HIST_FIELD_FL_HEX)
flags_str = "hex";
+ else if (hist_field->flags & HIST_FIELD_FL_SYM)
+ flags_str = "sym";
+ else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
+ flags_str = "sym-offset";
return flags_str;
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (8 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 09/23] tracing: Add hist trigger 'sym' and 'sym-offset' modifiers Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-03-02 17:39 ` Steven Rostedt
2016-02-26 16:01 ` [PATCH v15 11/23] tracing: Add hist trigger 'syscall' modifier Tom Zanussi
` (12 subsequent siblings)
22 siblings, 1 reply; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to have common_pid field values displayed as program names
in the output by appending '.execname' to a common_pid field name:
# echo hist:keys=common_pid.execname ... \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 3 +-
kernel/trace/trace_events_hist.c | 100 ++++++++++++++++++++++++++++++++++++++-
2 files changed, 101 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 202220c..bfcbfee 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3848,7 +3848,8 @@ static const char readme_msg[] =
"\t following modifiers to the field name, as applicable:\n\n"
"\t .hex display a number as a hex value\n"
"\t .sym display an address as a symbol\n"
- "\t .sym-offset display an address as a symbol and offset\n\n"
+ "\t .sym-offset display an address as a symbol and offset\n"
+ "\t .execname display a common_pid as a program name\n\n"
"\t The 'pause' parameter can be used to pause an existing hist\n"
"\t trigger or to start a hist trigger but not log any events\n"
"\t until told to do so. 'continue' can be used to start or\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index fd4de16..b173f8a 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -83,6 +83,7 @@ enum hist_field_flags {
HIST_FIELD_FL_HEX = 8,
HIST_FIELD_FL_SYM = 16,
HIST_FIELD_FL_SYM_OFFSET = 32,
+ HIST_FIELD_FL_EXECNAME = 64,
};
struct hist_trigger_attrs {
@@ -232,6 +233,73 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
return ERR_PTR(ret);
}
+static inline void save_comm(char *comm, struct task_struct *task)
+{
+ if (!task->pid) {
+ strcpy(comm, "<idle>");
+ return;
+ }
+
+ if (WARN_ON_ONCE(task->pid < 0)) {
+ strcpy(comm, "<XXX>");
+ return;
+ }
+
+ memcpy(comm, task->comm, TASK_COMM_LEN);
+}
+
+static void hist_trigger_elt_free(struct tracing_map_elt *elt)
+{
+ kfree((char *)elt->private_data);
+}
+
+static int hist_trigger_elt_alloc(struct tracing_map_elt *elt)
+{
+ struct hist_trigger_data *hist_data = elt->map->private_data;
+ struct hist_field *key_field;
+ unsigned int i;
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+
+ if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
+ unsigned int size = TASK_COMM_LEN + 1;
+
+ elt->private_data = kzalloc(size, GFP_KERNEL);
+ if (!elt->private_data)
+ return -ENOMEM;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static void hist_trigger_elt_copy(struct tracing_map_elt *to,
+ struct tracing_map_elt *from)
+{
+ char *comm_from = from->private_data;
+ char *comm_to = to->private_data;
+
+ if (comm_from)
+ memcpy(comm_to, comm_from, TASK_COMM_LEN + 1);
+}
+
+static void hist_trigger_elt_init(struct tracing_map_elt *elt)
+{
+ char *comm = elt->private_data;
+
+ if (comm)
+ save_comm(comm, current);
+}
+
+static const struct tracing_map_ops hist_trigger_ops = {
+ .elt_alloc = hist_trigger_elt_alloc,
+ .elt_copy = hist_trigger_elt_copy,
+ .elt_free = hist_trigger_elt_free,
+ .elt_init = hist_trigger_elt_init,
+};
+
static void destroy_hist_field(struct hist_field *hist_field)
{
kfree(hist_field);
@@ -399,6 +467,9 @@ static int create_key_field(struct hist_trigger_data *hist_data,
flags |= HIST_FIELD_FL_SYM;
else if (strcmp(field_str, "sym-offset") == 0)
flags |= HIST_FIELD_FL_SYM_OFFSET;
+ else if ((strcmp(field_str, "execname") == 0) &&
+ (strcmp(field_name, "common_pid") == 0))
+ flags |= HIST_FIELD_FL_EXECNAME;
else {
ret = -EINVAL;
goto out;
@@ -618,11 +689,27 @@ static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
return 0;
}
+static bool need_trigger_ops(struct hist_trigger_data *hist_data)
+{
+ struct hist_field *key_field;
+ unsigned int i;
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+
+ if (key_field->flags & HIST_FIELD_FL_EXECNAME)
+ return true;
+ }
+
+ return false;
+}
+
static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,
struct hist_trigger_attrs *attrs,
struct trace_event_file *file)
{
+ const struct tracing_map_ops *trigger_ops = NULL;
struct hist_trigger_data *hist_data;
int ret = 0;
@@ -640,8 +727,11 @@ create_hist_data(unsigned int map_bits,
if (ret)
goto free;
+ if (need_trigger_ops(hist_data))
+ trigger_ops = &hist_trigger_ops;
+
hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
- NULL, hist_data);
+ trigger_ops, hist_data);
if (IS_ERR(hist_data->map)) {
ret = PTR_ERR(hist_data->map);
hist_data->map = NULL;
@@ -752,6 +842,12 @@ hist_trigger_entry_print(struct seq_file *m,
sprint_symbol(str, uval);
seq_printf(m, "%s: [%llx] %-55s",
key_field->field->name, uval, str);
+ } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
+ char *comm = elt->private_data;
+
+ uval = *(u64 *)(key + key_field->offset);
+ seq_printf(m, "%s: %-16s[%10llu]",
+ key_field->field->name, comm, uval);
} else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
@@ -871,6 +967,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field)
flags_str = "sym";
else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
flags_str = "sym-offset";
+ else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
+ flags_str = "execname";
return flags_str;
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 11/23] tracing: Add hist trigger 'syscall' modifier
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (9 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 12/23] tracing: Add hist trigger support for stacktraces as keys Tom Zanussi
` (11 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to have syscall id fields displayed as syscall names in
the output by appending '.syscall' to field names:
# echo hist:keys=aaa.syscall ... \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 3 ++-
kernel/trace/trace_events_hist.c | 15 +++++++++++++++
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bfcbfee..d1890cc 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3849,7 +3849,8 @@ static const char readme_msg[] =
"\t .hex display a number as a hex value\n"
"\t .sym display an address as a symbol\n"
"\t .sym-offset display an address as a symbol and offset\n"
- "\t .execname display a common_pid as a program name\n\n"
+ "\t .execname display a common_pid as a program name\n"
+ "\t .syscall display a syscall id as a syscall name\n\n"
"\t The 'pause' parameter can be used to pause an existing hist\n"
"\t trigger or to start a hist trigger but not log any events\n"
"\t until told to do so. 'continue' can be used to start or\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index b173f8a..e0b7ed4 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -84,6 +84,7 @@ enum hist_field_flags {
HIST_FIELD_FL_SYM = 16,
HIST_FIELD_FL_SYM_OFFSET = 32,
HIST_FIELD_FL_EXECNAME = 64,
+ HIST_FIELD_FL_SYSCALL = 128,
};
struct hist_trigger_attrs {
@@ -470,6 +471,8 @@ static int create_key_field(struct hist_trigger_data *hist_data,
else if ((strcmp(field_str, "execname") == 0) &&
(strcmp(field_name, "common_pid") == 0))
flags |= HIST_FIELD_FL_EXECNAME;
+ else if (strcmp(field_str, "syscall") == 0)
+ flags |= HIST_FIELD_FL_SYSCALL;
else {
ret = -EINVAL;
goto out;
@@ -848,6 +851,16 @@ hist_trigger_entry_print(struct seq_file *m,
uval = *(u64 *)(key + key_field->offset);
seq_printf(m, "%s: %-16s[%10llu]",
key_field->field->name, comm, uval);
+ } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
+ const char *syscall_name;
+
+ uval = *(u64 *)(key + key_field->offset);
+ syscall_name = get_syscall_name(uval);
+ if (!syscall_name)
+ syscall_name = "unknown_syscall";
+
+ seq_printf(m, "%s: %-30s[%3llu]",
+ key_field->field->name, syscall_name, uval);
} else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
@@ -969,6 +982,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field)
flags_str = "sym-offset";
else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
flags_str = "execname";
+ else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
+ flags_str = "syscall";
return flags_str;
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 12/23] tracing: Add hist trigger support for stacktraces as keys
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (10 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 11/23] tracing: Add hist trigger 'syscall' modifier Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 13/23] tracing: Support string type key properly Tom Zanussi
` (10 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
It's often useful to be able to use a stacktrace as a hash key, for
keeping a count of the number of times a particular call path resulted
in a trace event, for instance. Add a special key named 'stacktrace'
which can be used as key in a 'keys=' param for this purpose:
# echo hist:keys=stacktrace ... \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.c | 16 ++---
kernel/trace/trace_events_hist.c | 135 +++++++++++++++++++++++++++++----------
2 files changed, 109 insertions(+), 42 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d1890cc..1a652d8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3834,14 +3834,14 @@ static const char readme_msg[] =
"\t table using the key(s) and value(s) named, and the value of a\n"
"\t sum called 'hitcount' is incremented. Keys and values\n"
"\t correspond to fields in the event's format description. Keys\n"
- "\t can be any field. Compound keys consisting of up to two\n"
- "\t fields can be specified by the 'keys' keyword. Values must\n"
- "\t correspond to numeric fields. Sort keys consisting of up to\n"
- "\t two fields can be specified using the 'sort' keyword. The\n"
- "\t sort direction can be modified by appending '.descending' or\n"
- "\t '.ascending' to a sort field. The 'size' parameter can be\n"
- "\t used to specify more or fewer than the default 2048 entries\n"
- "\t for the hashtable size.\n\n"
+ "\t can be any field, or the special string 'stacktrace'.\n"
+ "\t Compound keys consisting of up to two fields can be specified\n"
+ "\t by the 'keys' keyword. Values must correspond to numeric\n"
+ "\t fields. Sort keys consisting of up to two fields can be\n"
+ "\t specified using the 'sort' keyword. The sort direction can\n"
+ "\t be modified by appending '.descending' or '.ascending' to a\n"
+ "\t sort field. The 'size' parameter can be used to specify more\n"
+ "\t or fewer than the default 2048 entries for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
"\t table in its entirety to stdout. The default format used to\n"
"\t display a given field can be modified by appending any of the\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index e0b7ed4..c20d8e0 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -35,6 +35,11 @@ struct hist_field {
unsigned int offset;
};
+static u64 hist_field_none(struct hist_field *field, void *event)
+{
+ return 0;
+}
+
static u64 hist_field_counter(struct hist_field *field, void *event)
{
return 1;
@@ -73,8 +78,12 @@ DEFINE_HIST_FIELD_FN(u8);
#define for_each_hist_key_field(i, hist_data) \
for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
+#define HIST_STACKTRACE_DEPTH 16
+#define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
+#define HIST_STACKTRACE_SKIP 5
+
#define HITCOUNT_IDX 0
-#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + sizeof(u64))
+#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
enum hist_field_flags {
HIST_FIELD_FL_HITCOUNT = 1,
@@ -85,6 +94,7 @@ enum hist_field_flags {
HIST_FIELD_FL_SYM_OFFSET = 32,
HIST_FIELD_FL_EXECNAME = 64,
HIST_FIELD_FL_SYSCALL = 128,
+ HIST_FIELD_FL_STACKTRACE = 256,
};
struct hist_trigger_attrs {
@@ -323,6 +333,11 @@ static struct hist_field *create_hist_field(struct ftrace_event_field *field,
goto out;
}
+ if (flags & HIST_FIELD_FL_STACKTRACE) {
+ hist_field->fn = hist_field_none;
+ goto out;
+ }
+
if (is_string_field(field)) {
flags |= HIST_FIELD_FL_STRING;
hist_field->fn = hist_field_string;
@@ -452,7 +467,6 @@ static int create_key_field(struct hist_trigger_data *hist_data,
struct ftrace_event_field *field = NULL;
unsigned long flags = 0;
unsigned int key_size;
- char *field_name;
int ret = 0;
if (WARN_ON(key_idx >= TRACING_MAP_FIELDS_MAX))
@@ -460,33 +474,39 @@ static int create_key_field(struct hist_trigger_data *hist_data,
flags |= HIST_FIELD_FL_KEY;
- field_name = strsep(&field_str, ".");
- if (field_str) {
- if (strcmp(field_str, "hex") == 0)
- flags |= HIST_FIELD_FL_HEX;
- else if (strcmp(field_str, "sym") == 0)
- flags |= HIST_FIELD_FL_SYM;
- else if (strcmp(field_str, "sym-offset") == 0)
- flags |= HIST_FIELD_FL_SYM_OFFSET;
- else if ((strcmp(field_str, "execname") == 0) &&
- (strcmp(field_name, "common_pid") == 0))
- flags |= HIST_FIELD_FL_EXECNAME;
- else if (strcmp(field_str, "syscall") == 0)
- flags |= HIST_FIELD_FL_SYSCALL;
- else {
+ if (strcmp(field_str, "stacktrace") == 0) {
+ flags |= HIST_FIELD_FL_STACKTRACE;
+ key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
+ } else {
+ char *field_name = strsep(&field_str, ".");
+
+ if (field_str) {
+ if (strcmp(field_str, "hex") == 0)
+ flags |= HIST_FIELD_FL_HEX;
+ else if (strcmp(field_str, "sym") == 0)
+ flags |= HIST_FIELD_FL_SYM;
+ else if (strcmp(field_str, "sym-offset") == 0)
+ flags |= HIST_FIELD_FL_SYM_OFFSET;
+ else if ((strcmp(field_str, "execname") == 0) &&
+ (strcmp(field_name, "common_pid") == 0))
+ flags |= HIST_FIELD_FL_EXECNAME;
+ else if (strcmp(field_str, "syscall") == 0)
+ flags |= HIST_FIELD_FL_SYSCALL;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ field = trace_find_event_field(file->event_call, field_name);
+ if (!field) {
ret = -EINVAL;
goto out;
}
- }
- field = trace_find_event_field(file->event_call, field_name);
- if (!field) {
- ret = -EINVAL;
- goto out;
+ key_size = field->size;
}
- key_size = field->size;
-
hist_data->fields[key_idx] = create_hist_field(field, flags);
if (!hist_data->fields[key_idx]) {
ret = -ENOMEM;
@@ -673,7 +693,9 @@ static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
field = hist_field->field;
- if (is_string_field(field))
+ if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
+ cmp_fn = tracing_map_cmp_none;
+ else if (is_string_field(field))
cmp_fn = tracing_map_cmp_string;
else
cmp_fn = tracing_map_cmp_num(field->size,
@@ -780,7 +802,9 @@ static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
static void event_hist_trigger(struct event_trigger_data *data, void *rec)
{
struct hist_trigger_data *hist_data = data->private_data;
+ unsigned long entries[HIST_STACKTRACE_DEPTH];
char compound_key[HIST_KEY_SIZE_MAX];
+ struct stack_trace stacktrace;
struct hist_field *key_field;
struct tracing_map_elt *elt;
u64 field_contents;
@@ -793,15 +817,27 @@ static void event_hist_trigger(struct event_trigger_data *data, void *rec)
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
- field_contents = key_field->fn(key_field, rec);
- if (key_field->flags & HIST_FIELD_FL_STRING)
- key = (void *)(unsigned long)field_contents;
- else
- key = (void *)&field_contents;
+ if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
+ stacktrace.max_entries = HIST_STACKTRACE_DEPTH;
+ stacktrace.entries = entries;
+ stacktrace.nr_entries = 0;
+ stacktrace.skip = HIST_STACKTRACE_SKIP;
- if (hist_data->n_keys > 1) {
- memcpy(compound_key + key_field->offset, key,
- key_field->size);
+ memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE);
+ save_stack_trace(&stacktrace);
+
+ key = entries;
+ } else {
+ field_contents = key_field->fn(key_field, rec);
+ if (key_field->flags & HIST_FIELD_FL_STRING)
+ key = (void *)(unsigned long)field_contents;
+ else
+ key = (void *)&field_contents;
+
+ if (hist_data->n_keys > 1) {
+ memcpy(compound_key + key_field->offset, key,
+ key_field->size);
+ }
}
}
@@ -813,6 +849,24 @@ static void event_hist_trigger(struct event_trigger_data *data, void *rec)
hist_trigger_elt_update(hist_data, elt, rec);
}
+static void hist_trigger_stacktrace_print(struct seq_file *m,
+ unsigned long *stacktrace_entries,
+ unsigned int max_entries)
+{
+ char str[KSYM_SYMBOL_LEN];
+ unsigned int spaces = 8;
+ unsigned int i;
+
+ for (i = 0; i < max_entries; i++) {
+ if (stacktrace_entries[i] == ULONG_MAX)
+ return;
+
+ seq_printf(m, "%*c", 1 + spaces, ' ');
+ sprint_symbol(str, stacktrace_entries[i]);
+ seq_printf(m, "%s\n", str);
+ }
+}
+
static void
hist_trigger_entry_print(struct seq_file *m,
struct hist_trigger_data *hist_data, void *key,
@@ -820,6 +874,7 @@ hist_trigger_entry_print(struct seq_file *m,
{
struct hist_field *key_field;
char str[KSYM_SYMBOL_LEN];
+ bool multiline = false;
unsigned int i;
u64 uval;
@@ -861,6 +916,12 @@ hist_trigger_entry_print(struct seq_file *m,
seq_printf(m, "%s: %-30s[%3llu]",
key_field->field->name, syscall_name, uval);
+ } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
+ seq_puts(m, "stacktrace:\n");
+ hist_trigger_stacktrace_print(m,
+ key + key_field->offset,
+ HIST_STACKTRACE_DEPTH);
+ multiline = true;
} else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
@@ -871,7 +932,10 @@ hist_trigger_entry_print(struct seq_file *m,
}
}
- seq_puts(m, " }");
+ if (!multiline)
+ seq_puts(m, " ");
+
+ seq_puts(m, "}");
seq_printf(m, " hitcount: %10llu",
tracing_map_read_sum(elt, HITCOUNT_IDX));
@@ -1015,7 +1079,10 @@ static int event_hist_trigger_print(struct seq_file *m,
if (i > hist_data->n_vals)
seq_puts(m, ",");
- hist_field_print(m, key_field);
+ if (key_field->flags & HIST_FIELD_FL_STACKTRACE)
+ seq_puts(m, "stacktrace");
+ else
+ hist_field_print(m, key_field);
}
seq_puts(m, ":vals=");
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 13/23] tracing: Support string type key properly
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (11 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 12/23] tracing: Add hist trigger support for stacktraces as keys Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 14/23] tracing: Remove restriction on string position in hist trigger keys Tom Zanussi
` (9 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
From: Namhyung Kim <namhyung@kernel.org>
The string in a trace event is usually recorded as dynamic array which
is variable length. But current hist code only support fixed length
array so it cannot support most strings.
This patch fixes it by checking filter_type of the field and get
proper pointer with it. With this, it can get a histogram of exec()
based on filenames like below:
# cd /sys/kernel/tracing/events/sched/sched_process_exec
# cat 'hist:key=filename' > trigger
# ps
PID TTY TIME CMD
1 ? 00:00:00 init
29 ? 00:00:00 sh
38 ? 00:00:00 ps
# ls
enable filter format hist id trigger
# cat hist
# trigger info: hist:keys=filename:vals=hitcount:sort=hitcount:size=2048 [active]
{ filename: /usr/bin/ps } hitcount: 1
{ filename: /usr/bin/ls } hitcount: 1
{ filename: /usr/bin/cat } hitcount: 1
Totals:
Hits: 3
Entries: 3
Dropped: 0
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
kernel/trace/trace_events_hist.c | 47 +++++++++++++++++++++++++++++++++++++---
1 file changed, 44 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index c20d8e0..277aa57 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -52,6 +52,22 @@ static u64 hist_field_string(struct hist_field *hist_field, void *event)
return (u64)(unsigned long)addr;
}
+static u64 hist_field_dynstring(struct hist_field *hist_field, void *event)
+{
+ u32 str_item = *(u32 *)(event + hist_field->field->offset);
+ int str_loc = str_item & 0xffff;
+ char *addr = (char *)(event + str_loc);
+
+ return (u64)addr;
+}
+
+static u64 hist_field_pstring(struct hist_field *hist_field, void *event)
+{
+ char **addr = (char **)(event + hist_field->field->offset);
+
+ return (u64)*addr;
+}
+
#define DEFINE_HIST_FIELD_FN(type) \
static u64 hist_field_##type(struct hist_field *hist_field, void *event)\
{ \
@@ -340,7 +356,13 @@ static struct hist_field *create_hist_field(struct ftrace_event_field *field,
if (is_string_field(field)) {
flags |= HIST_FIELD_FL_STRING;
- hist_field->fn = hist_field_string;
+
+ if (field->filter_type == FILTER_STATIC_STRING)
+ hist_field->fn = hist_field_string;
+ else if (field->filter_type == FILTER_DYN_STRING)
+ hist_field->fn = hist_field_dynstring;
+ else
+ hist_field->fn = hist_field_pstring;
} else {
hist_field->fn = select_value_fn(field->size,
field->is_signed);
@@ -504,7 +526,10 @@ static int create_key_field(struct hist_trigger_data *hist_data,
goto out;
}
- key_size = field->size;
+ if (is_string_field(field)) /* should be last key field */
+ key_size = HIST_KEY_SIZE_MAX - key_offset;
+ else
+ key_size = field->size;
}
hist_data->fields[key_idx] = create_hist_field(field, flags);
@@ -835,8 +860,24 @@ static void event_hist_trigger(struct event_trigger_data *data, void *rec)
key = (void *)&field_contents;
if (hist_data->n_keys > 1) {
+ /* ensure NULL-termination */
+ size_t size = key_field->size - 1;
+
+ if (key_field->flags & HIST_FIELD_FL_STRING) {
+ struct ftrace_event_field *field;
+
+ field = key_field->field;
+ if (field->filter_type == FILTER_DYN_STRING)
+ size = *(u32 *)(rec + field->offset) >> 16;
+ else if (field->filter_type == FILTER_PTR_STRING)
+ size = strlen(key);
+
+ if (size > key_field->size - 1)
+ size = key_field->size - 1;
+ }
+
memcpy(compound_key + key_field->offset, key,
- key_field->size);
+ size);
}
}
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 14/23] tracing: Remove restriction on string position in hist trigger keys
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (12 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 13/23] tracing: Support string type key properly Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 15/23] tracing: Add enable_hist/disable_hist triggers Tom Zanussi
` (8 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
If we assume the maximum size for a string field, we don't have to
worry about its position. Since we only allow two keys in a compound
key and having more than one string key in a given compound key
doesn't make much sense anyway, trading a bit of extra space instead
of introducing an arbitrary restriction makes more sense.
We also need to use the event field size for static strings when
copying the contents, otherwise we get random garbage in the key.
Also, cast string return values to avoid warnings on 32-bit compiles.
Finally, rearrange the code without changing any functionality by
moving the compound key updating code into a separate function.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace_events_hist.c | 67 ++++++++++++++++++++++------------------
1 file changed, 37 insertions(+), 30 deletions(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 277aa57..ce08277 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -58,14 +58,14 @@ static u64 hist_field_dynstring(struct hist_field *hist_field, void *event)
int str_loc = str_item & 0xffff;
char *addr = (char *)(event + str_loc);
- return (u64)addr;
+ return (u64)(unsigned long)addr;
}
static u64 hist_field_pstring(struct hist_field *hist_field, void *event)
{
char **addr = (char **)(event + hist_field->field->offset);
- return (u64)*addr;
+ return (u64)(unsigned long)*addr;
}
#define DEFINE_HIST_FIELD_FN(type) \
@@ -526,8 +526,8 @@ static int create_key_field(struct hist_trigger_data *hist_data,
goto out;
}
- if (is_string_field(field)) /* should be last key field */
- key_size = HIST_KEY_SIZE_MAX - key_offset;
+ if (is_string_field(field))
+ key_size = MAX_FILTER_STR_VAL;
else
key_size = field->size;
}
@@ -824,9 +824,34 @@ static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
}
}
+static inline void add_to_key(char *compound_key, void *key,
+ struct hist_field *key_field, void *rec)
+{
+ size_t size = key_field->size;
+
+ if (key_field->flags & HIST_FIELD_FL_STRING) {
+ struct ftrace_event_field *field;
+
+ field = key_field->field;
+ if (field->filter_type == FILTER_DYN_STRING)
+ size = *(u32 *)(rec + field->offset) >> 16;
+ else if (field->filter_type == FILTER_PTR_STRING)
+ size = strlen(key);
+ else if (field->filter_type == FILTER_STATIC_STRING)
+ size = field->size;
+
+ /* ensure NULL-termination */
+ if (size > key_field->size - 1)
+ size = key_field->size - 1;
+ }
+
+ memcpy(compound_key + key_field->offset, key, size);
+}
+
static void event_hist_trigger(struct event_trigger_data *data, void *rec)
{
struct hist_trigger_data *hist_data = data->private_data;
+ bool use_compound_key = (hist_data->n_keys > 1);
unsigned long entries[HIST_STACKTRACE_DEPTH];
char compound_key[HIST_KEY_SIZE_MAX];
struct stack_trace stacktrace;
@@ -836,8 +861,7 @@ static void event_hist_trigger(struct event_trigger_data *data, void *rec)
void *key = NULL;
unsigned int i;
- if (hist_data->n_keys > 1)
- memset(compound_key, 0, hist_data->key_size);
+ memset(compound_key, 0, hist_data->key_size);
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
@@ -854,35 +878,18 @@ static void event_hist_trigger(struct event_trigger_data *data, void *rec)
key = entries;
} else {
field_contents = key_field->fn(key_field, rec);
- if (key_field->flags & HIST_FIELD_FL_STRING)
+ if (key_field->flags & HIST_FIELD_FL_STRING) {
key = (void *)(unsigned long)field_contents;
- else
+ use_compound_key = true;
+ } else
key = (void *)&field_contents;
-
- if (hist_data->n_keys > 1) {
- /* ensure NULL-termination */
- size_t size = key_field->size - 1;
-
- if (key_field->flags & HIST_FIELD_FL_STRING) {
- struct ftrace_event_field *field;
-
- field = key_field->field;
- if (field->filter_type == FILTER_DYN_STRING)
- size = *(u32 *)(rec + field->offset) >> 16;
- else if (field->filter_type == FILTER_PTR_STRING)
- size = strlen(key);
-
- if (size > key_field->size - 1)
- size = key_field->size - 1;
- }
-
- memcpy(compound_key + key_field->offset, key,
- size);
- }
}
+
+ if (use_compound_key)
+ add_to_key(compound_key, key, key_field, rec);
}
- if (hist_data->n_keys > 1)
+ if (use_compound_key)
key = compound_key;
elt = tracing_map_insert(hist_data->map, key);
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 15/23] tracing: Add enable_hist/disable_hist triggers
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (13 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 14/23] tracing: Remove restriction on string position in hist trigger keys Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 16/23] tracing: Add 'hist' trigger Documentation Tom Zanussi
` (7 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Similar to enable_event/disable_event triggers, these triggers enable
and disable the aggregation of events into maps rather than enabling
and disabling their writing into the trace buffer.
They can be used to automatically start and stop hist triggers based
on a matching filter condition.
If there's a paused hist trigger on system:event, the following would
start it when the filter condition was hit:
# echo enable_hist:system:event [ if filter] > event/trigger
And the following would disable a running system:event hist trigger:
# echo disable_hist:system:event [ if filter] > event/trigger
See Documentation/trace/events.txt for real examples.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
include/linux/trace_events.h | 1 +
kernel/trace/trace.c | 8 +++
kernel/trace/trace.h | 32 ++++++++++
kernel/trace/trace_events_hist.c | 115 ++++++++++++++++++++++++++++++++++++
kernel/trace/trace_events_trigger.c | 71 ++++++++++++----------
5 files changed, 196 insertions(+), 31 deletions(-)
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index e61816d..70f8fc4 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -418,6 +418,7 @@ enum event_trigger_type {
ETT_STACKTRACE = (1 << 2),
ETT_EVENT_ENABLE = (1 << 3),
ETT_EVENT_HIST = (1 << 4),
+ ETT_HIST_ENABLE = (1 << 5),
};
extern int filter_match_preds(struct event_filter *filter, void *rec);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1a652d8..8834fd2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3798,6 +3798,10 @@ static const char readme_msg[] =
"\t trigger: traceon, traceoff\n"
"\t enable_event:<system>:<event>\n"
"\t disable_event:<system>:<event>\n"
+#ifdef CONFIG_HIST_TRIGGERS
+ "\t enable_hist:<system>:<event>\n"
+ "\t disable_hist:<system>:<event>\n"
+#endif
#ifdef CONFIG_STACKTRACE
"\t\t stacktrace\n"
#endif
@@ -3858,6 +3862,10 @@ static const char readme_msg[] =
"\t The 'clear' parameter will clear the contents of a running\n"
"\t hist trigger and leave its current paused/active state\n"
"\t unchanged.\n\n"
+ "\t The enable_hist and disable_hist triggers can be used to\n"
+ "\t have one event conditionally start and stop another event's\n"
+ "\t already-attached hist trigger. The syntax is analagous to\n"
+ "\t the enable_event and disable_event triggers.\n"
#endif
;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index bd04013..973427e 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1165,8 +1165,10 @@ extern const struct file_operations event_hist_fops;
#ifdef CONFIG_HIST_TRIGGERS
extern int register_trigger_hist_cmd(void);
+extern int register_trigger_hist_enable_disable_cmds(void);
#else
static inline int register_trigger_hist_cmd(void) { return 0; }
+static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
#endif
extern int register_trigger_cmds(void);
@@ -1184,6 +1186,34 @@ struct event_trigger_data {
struct list_head list;
};
+/* Avoid typos */
+#define ENABLE_EVENT_STR "enable_event"
+#define DISABLE_EVENT_STR "disable_event"
+#define ENABLE_HIST_STR "enable_hist"
+#define DISABLE_HIST_STR "disable_hist"
+
+struct enable_trigger_data {
+ struct trace_event_file *file;
+ bool enable;
+ bool hist;
+};
+
+extern int event_enable_trigger_print(struct seq_file *m,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *data);
+extern void event_enable_trigger_free(struct event_trigger_ops *ops,
+ struct event_trigger_data *data);
+extern int event_enable_trigger_func(struct event_command *cmd_ops,
+ struct trace_event_file *file,
+ char *glob, char *cmd, char *param);
+extern int event_enable_register_trigger(char *glob,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *data,
+ struct trace_event_file *file);
+extern void event_enable_unregister_trigger(char *glob,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *test,
+ struct trace_event_file *file);
extern void trigger_data_free(struct event_trigger_data *data);
extern int event_trigger_init(struct event_trigger_ops *ops,
struct event_trigger_data *data);
@@ -1197,6 +1227,8 @@ extern int set_trigger_filter(char *filter_str,
struct event_trigger_data *trigger_data,
struct trace_event_file *file);
extern int register_event_command(struct event_command *cmd);
+extern int unregister_event_command(struct event_command *cmd);
+extern int register_trigger_hist_enable_disable_cmds(void);
/**
* struct event_trigger_ops - callbacks for trace event triggers
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index ce08277..c3ddde1 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1387,3 +1387,118 @@ __init int register_trigger_hist_cmd(void)
return ret;
}
+
+static void
+hist_enable_trigger(struct event_trigger_data *data, void *rec)
+{
+ struct enable_trigger_data *enable_data = data->private_data;
+ struct event_trigger_data *test;
+
+ list_for_each_entry_rcu(test, &enable_data->file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ if (enable_data->enable)
+ test->paused = false;
+ else
+ test->paused = true;
+ break;
+ }
+ }
+}
+
+static void
+hist_enable_count_trigger(struct event_trigger_data *data, void *rec)
+{
+ if (!data->count)
+ return;
+
+ if (data->count != -1)
+ (data->count)--;
+
+ hist_enable_trigger(data, rec);
+}
+
+static struct event_trigger_ops hist_enable_trigger_ops = {
+ .func = hist_enable_trigger,
+ .print = event_enable_trigger_print,
+ .init = event_trigger_init,
+ .free = event_enable_trigger_free,
+};
+
+static struct event_trigger_ops hist_enable_count_trigger_ops = {
+ .func = hist_enable_count_trigger,
+ .print = event_enable_trigger_print,
+ .init = event_trigger_init,
+ .free = event_enable_trigger_free,
+};
+
+static struct event_trigger_ops hist_disable_trigger_ops = {
+ .func = hist_enable_trigger,
+ .print = event_enable_trigger_print,
+ .init = event_trigger_init,
+ .free = event_enable_trigger_free,
+};
+
+static struct event_trigger_ops hist_disable_count_trigger_ops = {
+ .func = hist_enable_count_trigger,
+ .print = event_enable_trigger_print,
+ .init = event_trigger_init,
+ .free = event_enable_trigger_free,
+};
+
+static struct event_trigger_ops *
+hist_enable_get_trigger_ops(char *cmd, char *param)
+{
+ struct event_trigger_ops *ops;
+ bool enable;
+
+ enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
+
+ if (enable)
+ ops = param ? &hist_enable_count_trigger_ops :
+ &hist_enable_trigger_ops;
+ else
+ ops = param ? &hist_disable_count_trigger_ops :
+ &hist_disable_trigger_ops;
+
+ return ops;
+}
+
+static struct event_command trigger_hist_enable_cmd = {
+ .name = ENABLE_HIST_STR,
+ .trigger_type = ETT_HIST_ENABLE,
+ .func = event_enable_trigger_func,
+ .reg = event_enable_register_trigger,
+ .unreg = event_enable_unregister_trigger,
+ .get_trigger_ops = hist_enable_get_trigger_ops,
+ .set_filter = set_trigger_filter,
+};
+
+static struct event_command trigger_hist_disable_cmd = {
+ .name = DISABLE_HIST_STR,
+ .trigger_type = ETT_HIST_ENABLE,
+ .func = event_enable_trigger_func,
+ .reg = event_enable_register_trigger,
+ .unreg = event_enable_unregister_trigger,
+ .get_trigger_ops = hist_enable_get_trigger_ops,
+ .set_filter = set_trigger_filter,
+};
+
+static __init void unregister_trigger_hist_enable_disable_cmds(void)
+{
+ unregister_event_command(&trigger_hist_enable_cmd);
+ unregister_event_command(&trigger_hist_disable_cmd);
+}
+
+__init int register_trigger_hist_enable_disable_cmds(void)
+{
+ int ret;
+
+ ret = register_event_command(&trigger_hist_enable_cmd);
+ if (WARN_ON(ret < 0))
+ return ret;
+ ret = register_event_command(&trigger_hist_disable_cmd);
+ if (WARN_ON(ret < 0))
+ unregister_trigger_hist_enable_disable_cmds();
+
+ return ret;
+}
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 7e080a4..03109f1 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -352,7 +352,7 @@ __init int register_event_command(struct event_command *cmd)
* Currently we only unregister event commands from __init, so mark
* this __init too.
*/
-static __init int unregister_event_command(struct event_command *cmd)
+__init int unregister_event_command(struct event_command *cmd)
{
struct event_command *p, *n;
int ret = -ENODEV;
@@ -1066,15 +1066,6 @@ static __init void unregister_trigger_traceon_traceoff_cmds(void)
unregister_event_command(&trigger_traceoff_cmd);
}
-/* Avoid typos */
-#define ENABLE_EVENT_STR "enable_event"
-#define DISABLE_EVENT_STR "disable_event"
-
-struct enable_trigger_data {
- struct trace_event_file *file;
- bool enable;
-};
-
static void
event_enable_trigger(struct event_trigger_data *data, void *rec)
{
@@ -1104,14 +1095,16 @@ event_enable_count_trigger(struct event_trigger_data *data, void *rec)
event_enable_trigger(data, rec);
}
-static int
-event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
- struct event_trigger_data *data)
+int event_enable_trigger_print(struct seq_file *m,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
{
struct enable_trigger_data *enable_data = data->private_data;
seq_printf(m, "%s:%s:%s",
- enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
+ enable_data->hist ?
+ (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) :
+ (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR),
enable_data->file->event_call->class->system,
trace_event_name(enable_data->file->event_call));
@@ -1128,9 +1121,8 @@ event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
return 0;
}
-static void
-event_enable_trigger_free(struct event_trigger_ops *ops,
- struct event_trigger_data *data)
+void event_enable_trigger_free(struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
{
struct enable_trigger_data *enable_data = data->private_data;
@@ -1175,10 +1167,9 @@ static struct event_trigger_ops event_disable_count_trigger_ops = {
.free = event_enable_trigger_free,
};
-static int
-event_enable_trigger_func(struct event_command *cmd_ops,
- struct trace_event_file *file,
- char *glob, char *cmd, char *param)
+int event_enable_trigger_func(struct event_command *cmd_ops,
+ struct trace_event_file *file,
+ char *glob, char *cmd, char *param)
{
struct trace_event_file *event_enable_file;
struct enable_trigger_data *enable_data;
@@ -1187,6 +1178,7 @@ event_enable_trigger_func(struct event_command *cmd_ops,
struct trace_array *tr = file->tr;
const char *system;
const char *event;
+ bool hist = false;
char *trigger;
char *number;
bool enable;
@@ -1211,8 +1203,15 @@ event_enable_trigger_func(struct event_command *cmd_ops,
if (!event_enable_file)
goto out;
- enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
+#ifdef CONFIG_HIST_TRIGGERS
+ hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) ||
+ (strcmp(cmd, DISABLE_HIST_STR) == 0));
+ enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) ||
+ (strcmp(cmd, ENABLE_HIST_STR) == 0));
+#else
+ enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
+#endif
trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
ret = -ENOMEM;
@@ -1232,6 +1231,7 @@ event_enable_trigger_func(struct event_command *cmd_ops,
INIT_LIST_HEAD(&trigger_data->list);
RCU_INIT_POINTER(trigger_data->filter, NULL);
+ enable_data->hist = hist;
enable_data->enable = enable;
enable_data->file = event_enable_file;
trigger_data->private_data = enable_data;
@@ -1309,10 +1309,10 @@ event_enable_trigger_func(struct event_command *cmd_ops,
goto out;
}
-static int event_enable_register_trigger(char *glob,
- struct event_trigger_ops *ops,
- struct event_trigger_data *data,
- struct trace_event_file *file)
+int event_enable_register_trigger(char *glob,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *data,
+ struct trace_event_file *file)
{
struct enable_trigger_data *enable_data = data->private_data;
struct enable_trigger_data *test_enable_data;
@@ -1322,6 +1322,8 @@ static int event_enable_register_trigger(char *glob,
list_for_each_entry_rcu(test, &file->triggers, list) {
test_enable_data = test->private_data;
if (test_enable_data &&
+ (test->cmd_ops->trigger_type ==
+ data->cmd_ops->trigger_type) &&
(test_enable_data->file == enable_data->file)) {
ret = -EEXIST;
goto out;
@@ -1346,10 +1348,10 @@ out:
return ret;
}
-static void event_enable_unregister_trigger(char *glob,
- struct event_trigger_ops *ops,
- struct event_trigger_data *test,
- struct trace_event_file *file)
+void event_enable_unregister_trigger(char *glob,
+ struct event_trigger_ops *ops,
+ struct event_trigger_data *test,
+ struct trace_event_file *file)
{
struct enable_trigger_data *test_enable_data = test->private_data;
struct enable_trigger_data *enable_data;
@@ -1359,6 +1361,8 @@ static void event_enable_unregister_trigger(char *glob,
list_for_each_entry_rcu(data, &file->triggers, list) {
enable_data = data->private_data;
if (enable_data &&
+ (data->cmd_ops->trigger_type ==
+ test->cmd_ops->trigger_type) &&
(enable_data->file == test_enable_data->file)) {
unregistered = true;
list_del_rcu(&data->list);
@@ -1378,8 +1382,12 @@ event_enable_get_trigger_ops(char *cmd, char *param)
struct event_trigger_ops *ops;
bool enable;
+#ifdef CONFIG_HIST_TRIGGERS
+ enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) ||
+ (strcmp(cmd, ENABLE_HIST_STR) == 0));
+#else
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
-
+#endif
if (enable)
ops = param ? &event_enable_count_trigger_ops :
&event_enable_trigger_ops;
@@ -1450,6 +1458,7 @@ __init int register_trigger_cmds(void)
register_trigger_snapshot_cmd();
register_trigger_stacktrace_cmd();
register_trigger_enable_disable_cmds();
+ register_trigger_hist_enable_disable_cmds();
register_trigger_hist_cmd();
return 0;
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 16/23] tracing: Add 'hist' trigger Documentation
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (14 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 15/23] tracing: Add enable_hist/disable_hist triggers Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 17/23] tracing: Add support for multiple hist triggers per event Tom Zanussi
` (6 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Add documentation and usage examples for 'hist' triggers.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
Documentation/trace/events.txt | 1155 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 1155 insertions(+)
diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt
index c010be8..db223e8 100644
--- a/Documentation/trace/events.txt
+++ b/Documentation/trace/events.txt
@@ -512,3 +512,1158 @@ The following commands are supported:
Note that there can be only one traceon or traceoff trigger per
triggering event.
+
+- hist
+
+ This command aggregates event hits into a hash table keyed on one or
+ more trace event format fields (or stacktrace) and a set of running
+ totals derived from one or more trace event format fields and/or
+ event counts (hitcount).
+
+ The format of a hist trigger is as follows:
+
+ hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>]
+ [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue]
+ [:clear] [if <filter>]
+
+ When a matching event is hit, an entry is added to a hash table
+ using the key(s) and value(s) named. Keys and values correspond to
+ fields in the event's format description. Values must correspond to
+ numeric fields - on an event hit, the value(s) will be added to a
+ sum kept for that field. The special string 'hitcount' can be used
+ in place of an explicit value field - this is simply a count of
+ event hits. If 'values' isn't specified, an implicit 'hitcount'
+ value will be automatically created and used as the only value.
+ Keys can be any field, or the special string 'stacktrace', which
+ will use the event's kernel stacktrace as the key. The keywords
+ 'keys' or 'key' can be used to specify keys, and the keywords
+ 'values', 'vals', or 'val' can be used to specify values. Compound
+ keys consisting of up to two fields can be specified by the 'keys'
+ keyword. Hashing a compound key produces a unique entry in the
+ table for each unique combination of component keys, and can be
+ useful for providing more fine-grained summaries of event data.
+ Additionally, sort keys consisting of up to two fields can be
+ specified by the 'sort' keyword. If more than one field is
+ specified, the result will be a 'sort within a sort': the first key
+ is taken to be the primary sort key and the second the secondary
+ key.
+
+ 'hist' triggers add a 'hist' file to each event's subdirectory.
+ Reading the 'hist' file for the event will dump the hash table in
+ its entirety to stdout. Each printed hash table entry is a simple
+ list of the keys and values comprising the entry; keys are printed
+ first and are delineated by curly braces, and are followed by the
+ set of value fields for the entry. By default, numeric fields are
+ displayed as base-10 integers. This can be modified by appending
+ any of the following modifiers to the field name:
+
+ .hex display a number as a hex value
+ .sym display an address as a symbol
+ .sym-offset display an address as a symbol and offset
+ .syscall display a syscall id as a system call name
+ .execname display a common_pid as a program name
+
+ Note that in general the semantics of a given field aren't
+ interpreted when applying a modifier to it, but there are some
+ restrictions to be aware of in this regard:
+
+ - only the 'hex' modifier can be used for values (because values
+ are essentially sums, and the other modifiers don't make sense
+ in that context).
+ - the 'execname' modifier can only be used on a 'common_pid'. The
+ reason for this is that the execname is simply the 'comm' value
+ saved for the 'current' process when an event was triggered,
+ which is the same as the common_pid value saved by the event
+ tracing code. Trying to apply that comm value to other pid
+ values wouldn't be correct, and typically events that care save
+ pid-specific comm fields in the event itself.
+
+ A typical usage scenario would be the following to enable a hist
+ trigger, read its current contents, and then turn it off:
+
+ # echo 'hist:keys=skbaddr.hex:vals=len' > \
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
+
+ # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
+
+ # echo '!hist:keys=skbaddr.hex:vals=len' > \
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
+
+ The trigger file itself can be read to show the details of the
+ currently attached hist trigger. This information is also displayed
+ at the top of the 'hist' file when read.
+
+ By default, the size of the hash table is 2048 entries. The 'size'
+ parameter can be used to specify more or fewer than that. The units
+ are in terms of hashtable entries - if a run uses more entries than
+ specified, the results will show the number of 'drops', the number
+ of hits that were ignored. The size should be a power of 2 between
+ 128 and 131072 (any non- power-of-2 number specified will be rounded
+ up).
+
+ The 'sort' parameter can be used to specify a value field to sort
+ on. The default if unspecified is 'hitcount' and the default sort
+ order is 'ascending'. To sort in the opposite direction, append
+ .descending' to the sort key.
+
+ The 'pause' parameter can be used to pause an existing hist trigger
+ or to start a hist trigger but not log any events until told to do
+ so. 'continue' or 'cont' can be used to start or restart a paused
+ hist trigger.
+
+ The 'clear' parameter will clear the contents of a running hist
+ trigger and leave its current paused/active state.
+
+ Note that the 'pause', 'cont', and 'clear' parameters should be
+ applied using 'append' shell operator ('>>') if applied to an
+ existing trigger, rather than via the '>' operator, which will cause
+ the trigger to be removed through truncation.
+
+- enable_hist/disable_hist
+
+ The enable_hist and disable_hist triggers can be used to have one
+ event conditionally start and stop another event's already-attached
+ hist trigger. Any number of enable_hist and disable_hist triggers
+ can be attached to a given event, allowing that event to kick off
+ and stop aggregations on a host of other events.
+
+ The format is very similar to the enable/disable_event triggers:
+
+ enable_hist:<system>:<event>[:count]
+ disable_hist:<system>:<event>[:count]
+
+ Instead of enabling or disabling the tracing of the target event
+ into the trace buffer as the enable/disable_event triggers do, the
+ enable/disable_hist triggers enable or disable the aggregation of
+ the target event into a hash table.
+
+ A typical usage scenario for the enable_hist/disable_hist triggers
+ would be to first set up a paused hist trigger on some event,
+ followed by an enable_hist/disable_hist pair that turns the hist
+ aggregation on and off when conditions of interest are hit:
+
+ # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+
+ # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
+
+ # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
+
+ The above sets up an initially paused hist trigger which is unpaused
+ and starts aggregating events when a given program is executed, and
+ which stops aggregating when the process exits and the hist trigger
+ is paused again.
+
+ The examples below provide a more concrete illustration of the
+ concepts and typical usage patterns discussed above.
+
+
+6.2 'hist' trigger examples
+---------------------------
+
+ The first set of examples creates aggregations using the kmalloc
+ event. The fields that can be used for the hist trigger are listed
+ in the kmalloc event's format file:
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format
+ name: kmalloc
+ ID: 374
+ format:
+ field:unsigned short common_type; offset:0; size:2; signed:0;
+ field:unsigned char common_flags; offset:2; size:1; signed:0;
+ field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
+ field:int common_pid; offset:4; size:4; signed:1;
+
+ field:unsigned long call_site; offset:8; size:8; signed:0;
+ field:const void * ptr; offset:16; size:8; signed:0;
+ field:size_t bytes_req; offset:24; size:8; signed:0;
+ field:size_t bytes_alloc; offset:32; size:8; signed:0;
+ field:gfp_t gfp_flags; offset:40; size:4; signed:0;
+
+ We'll start by creating a hist trigger that generates a simple table
+ that lists the total number of bytes requested for each function in
+ the kernel that made one or more calls to kmalloc:
+
+ # echo 'hist:key=call_site:val=bytes_req' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ This tells the tracing system to create a 'hist' trigger using the
+ call_site field of the kmalloc event as the key for the table, which
+ just means that each unique call_site address will have an entry
+ created for it in the table. The 'val=bytes_req' parameter tells
+ the hist trigger that for each unique entry (call_site) in the
+ table, it should keep a running total of the number of bytes
+ requested by that call_site.
+
+ We'll let it run for awhile and then dump the contents of the 'hist'
+ file in the kmalloc event's subdirectory (for readability, a number
+ of entries have been omitted):
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active]
+
+ { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176
+ { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024
+ { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384
+ { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24
+ { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8
+ { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152
+ { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144
+ { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144
+ { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560
+ { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736
+ .
+ .
+ .
+ { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576
+ { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336
+ { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504
+ { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584
+ { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448
+ { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720
+ { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088
+ { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920
+ { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716
+ { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712
+ { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160
+ { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520
+
+ Totals:
+ Hits: 4610
+ Entries: 45
+ Dropped: 0
+
+ The output displays a line for each entry, beginning with the key
+ specified in the trigger, followed by the value(s) also specified in
+ the trigger. At the beginning of the output is a line that displays
+ the trigger info, which can also be displayed by reading the
+ 'trigger' file:
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+ hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active]
+
+ At the end of the output are a few lines that display the overall
+ totals for the run. The 'Hits' field shows the total number of
+ times the event trigger was hit, the 'Entries' field shows the total
+ number of used entries in the hash table, and the 'Dropped' field
+ shows the number of hits that were dropped because the number of
+ used entries for the run exceeded the maximum number of entries
+ allowed for the table (normally 0, but if not a hint that you may
+ want to increase the size of the table using the 'size' parameter).
+
+ Notice in the above output that there's an extra field, 'hitcount',
+ which wasn't specified in the trigger. Also notice that in the
+ trigger info output, there's a parameter, 'sort=hitcount', which
+ wasn't specified in the trigger either. The reason for that is that
+ every trigger implicitly keeps a count of the total number of hits
+ attributed to a given entry, called the 'hitcount'. That hitcount
+ information is explicitly displayed in the output, and in the
+ absence of a user-specified sort parameter, is used as the default
+ sort field.
+
+ The value 'hitcount' can be used in place of an explicit value in
+ the 'values' parameter if you don't really need to have any
+ particular field summed and are mainly interested in hit
+ frequencies.
+
+ To turn the hist trigger off, simply call up the trigger in the
+ command history and re-execute it with a '!' prepended:
+
+ # echo '!hist:key=call_site:val=bytes_req' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ Finally, notice that the call_site as displayed in the output above
+ isn't really very useful. It's an address, but normally addresses
+ are displayed in hex. To have a numeric field displayed as a hex
+ value, simply append '.hex' to the field name in the trigger:
+
+ # echo 'hist:key=call_site.hex:val=bytes_req' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active]
+
+ { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433
+ { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176
+ { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384
+ { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8
+ { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511
+ { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12
+ { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152
+ { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24
+ { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144
+ { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648
+ { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144
+ { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544
+ .
+ .
+ .
+ { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024
+ { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680
+ { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112
+ { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232
+ { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360
+ { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640
+ { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600
+ { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584
+ { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656
+ { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456
+ { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600
+
+ Totals:
+ Hits: 4775
+ Entries: 46
+ Dropped: 0
+
+ Even that's only marginally more useful - while hex values do look
+ more like addresses, what users are typically more interested in
+ when looking at text addresses are the corresponding symbols
+ instead. To have an address displayed as symbolic value instead,
+ simply append '.sym' or '.sym-offset' to the field name in the
+ trigger:
+
+ # echo 'hist:key=call_site.sym:val=bytes_req' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active]
+
+ { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024
+ { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7
+ { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7
+ { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40
+ { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128
+ { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528
+ { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624
+ { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96
+ { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464
+ { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304
+ { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128
+ { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424
+ .
+ .
+ .
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240
+ { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672
+ { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208
+ { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152
+ { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248
+ { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384
+ { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584
+ { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176
+ { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265
+
+ Totals:
+ Hits: 109928
+ Entries: 71
+ Dropped: 0
+
+ Because the default sort key above is 'hitcount', the above shows a
+ the list of call_sites by increasing hitcount, so that at the bottom
+ we see the functions that made the most kmalloc calls during the
+ run. If instead we we wanted to see the top kmalloc callers in
+ terms of the number of bytes requested rather than the number of
+ calls, and we wanted the top caller to appear at the top, we can use
+ the 'sort' parameter, along with the 'descending' modifier:
+
+ # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active]
+
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176
+ { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135
+ { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128
+ { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784
+ { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992
+ { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088
+ { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536
+ { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664
+ { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632
+ .
+ .
+ .
+ { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128
+ { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128
+ { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48
+ { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48
+ { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48
+ { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40
+ { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16
+ { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7
+
+ Totals:
+ Hits: 32133
+ Entries: 81
+ Dropped: 0
+
+ To display the offset and size information in addition to the symbol
+ name, just use 'sym-offset' instead:
+
+ # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active]
+
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720
+ { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936
+ { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832
+ { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040
+ { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072
+ { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696
+ { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640
+ { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456
+ .
+ .
+ .
+ { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128
+ { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96
+ { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96
+ { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84
+ { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7
+
+ Totals:
+ Hits: 26098
+ Entries: 64
+ Dropped: 0
+
+ We can also add multiple fields to the 'values' parameter. For
+ example, we might want to see the total number of bytes allocated
+ alongside bytes requested, and display the result sorted by bytes
+ allocated in a descending order:
+
+ # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active]
+
+ { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016
+ { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224
+ { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568
+ { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760
+ { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744
+ { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400
+ { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496
+ { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304
+ { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640
+ { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760
+ { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312
+ { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432
+ .
+ .
+ .
+ { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192
+ { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
+ { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
+ { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
+ { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128
+ { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96
+ { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64
+ { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8
+ { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8
+ { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8
+
+ Totals:
+ Hits: 66598
+ Entries: 65
+ Dropped: 0
+
+ Finally, to finish off our kmalloc example, instead of simply having
+ the hist trigger display symbolic call_sites, we can have the hist
+ trigger additionally display the complete set of kernel stack traces
+ that led to each call_site. To do that, we simply use the special
+ value 'stacktrace' for the key parameter:
+
+ # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \
+ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
+
+ The above trigger will use the kernel stack trace in effect when an
+ event is triggered as the key for the hash table. This allows the
+ enumeration of every kernel callpath that led up to a particular
+ event, along with a running total of any of the event fields for
+ that event. Here we tally bytes requested and bytes allocated for
+ every callpath in the system that led up to a kmalloc (in this case
+ every callpath to a kmalloc for a kernel compile):
+
+ # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist
+ # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active]
+
+ { stacktrace:
+ __kmalloc_track_caller+0x10b/0x1a0
+ kmemdup+0x20/0x50
+ hidraw_report_event+0x8a/0x120 [hid]
+ hid_report_raw_event+0x3ea/0x440 [hid]
+ hid_input_report+0x112/0x190 [hid]
+ hid_irq_in+0xc2/0x260 [usbhid]
+ __usb_hcd_giveback_urb+0x72/0x120
+ usb_giveback_urb_bh+0x9e/0xe0
+ tasklet_hi_action+0xf8/0x100
+ __do_softirq+0x114/0x2c0
+ irq_exit+0xa5/0xb0
+ do_IRQ+0x5a/0xf0
+ ret_from_intr+0x0/0x30
+ cpuidle_enter+0x17/0x20
+ cpu_startup_entry+0x315/0x3e0
+ rest_init+0x7c/0x80
+ } hitcount: 3 bytes_req: 21 bytes_alloc: 24
+ { stacktrace:
+ __kmalloc_track_caller+0x10b/0x1a0
+ kmemdup+0x20/0x50
+ hidraw_report_event+0x8a/0x120 [hid]
+ hid_report_raw_event+0x3ea/0x440 [hid]
+ hid_input_report+0x112/0x190 [hid]
+ hid_irq_in+0xc2/0x260 [usbhid]
+ __usb_hcd_giveback_urb+0x72/0x120
+ usb_giveback_urb_bh+0x9e/0xe0
+ tasklet_hi_action+0xf8/0x100
+ __do_softirq+0x114/0x2c0
+ irq_exit+0xa5/0xb0
+ do_IRQ+0x5a/0xf0
+ ret_from_intr+0x0/0x30
+ } hitcount: 3 bytes_req: 21 bytes_alloc: 24
+ { stacktrace:
+ kmem_cache_alloc_trace+0xeb/0x150
+ aa_alloc_task_context+0x27/0x40
+ apparmor_cred_prepare+0x1f/0x50
+ security_prepare_creds+0x16/0x20
+ prepare_creds+0xdf/0x1a0
+ SyS_capset+0xb5/0x200
+ system_call_fastpath+0x12/0x6a
+ } hitcount: 1 bytes_req: 32 bytes_alloc: 32
+ .
+ .
+ .
+ { stacktrace:
+ __kmalloc+0x11b/0x1b0
+ i915_gem_execbuffer2+0x6c/0x2c0 [i915]
+ drm_ioctl+0x349/0x670 [drm]
+ do_vfs_ioctl+0x2f0/0x4f0
+ SyS_ioctl+0x81/0xa0
+ system_call_fastpath+0x12/0x6a
+ } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808
+ { stacktrace:
+ __kmalloc+0x11b/0x1b0
+ load_elf_phdrs+0x76/0xa0
+ load_elf_binary+0x102/0x1650
+ search_binary_handler+0x97/0x1d0
+ do_execveat_common.isra.34+0x551/0x6e0
+ SyS_execve+0x3a/0x50
+ return_from_execve+0x0/0x23
+ } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048
+ { stacktrace:
+ kmem_cache_alloc_trace+0xeb/0x150
+ apparmor_file_alloc_security+0x27/0x40
+ security_file_alloc+0x16/0x20
+ get_empty_filp+0x93/0x1c0
+ path_openat+0x31/0x5f0
+ do_filp_open+0x3a/0x90
+ do_sys_open+0x128/0x220
+ SyS_open+0x1e/0x20
+ system_call_fastpath+0x12/0x6a
+ } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376
+ { stacktrace:
+ __kmalloc+0x11b/0x1b0
+ seq_buf_alloc+0x1b/0x50
+ seq_read+0x2cc/0x370
+ proc_reg_read+0x3d/0x80
+ __vfs_read+0x28/0xe0
+ vfs_read+0x86/0x140
+ SyS_read+0x46/0xb0
+ system_call_fastpath+0x12/0x6a
+ } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768
+
+ Totals:
+ Hits: 6085872
+ Entries: 253
+ Dropped: 0
+
+ If you key a hist trigger on common_pid, in order for example to
+ gather and display sorted totals for each process, you can use the
+ special .execname modifier to display the executable names for the
+ processes in the table rather than raw pids. The example below
+ keeps a per-process sum of total bytes read:
+
+ # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \
+ /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
+
+ # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist
+ # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active]
+
+ { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512
+ { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640
+ { common_pid: compiz [ 2889] } hitcount: 59 count: 254400
+ { common_pid: bash [ 8710] } hitcount: 3 count: 66369
+ { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739
+ { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648
+ { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216
+ { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396
+ { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264
+ { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424
+ { common_pid: gmain [ 1315] } hitcount: 18 count: 6336
+ .
+ .
+ .
+ { common_pid: postgres [ 1892] } hitcount: 2 count: 32
+ { common_pid: postgres [ 1891] } hitcount: 2 count: 32
+ { common_pid: gmain [ 8704] } hitcount: 2 count: 32
+ { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21
+ { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16
+ { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16
+ { common_pid: gdbus [ 2998] } hitcount: 1 count: 16
+ { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8
+ { common_pid: init [ 1] } hitcount: 2 count: 2
+
+ Totals:
+ Hits: 2116
+ Entries: 51
+ Dropped: 0
+
+ Similarly, if you key a hist trigger on syscall id, for example to
+ gather and display a list of systemwide syscall hits, you can use
+ the special .syscall modifier to display the syscall names rather
+ than raw ids. The example below keeps a running total of syscall
+ counts for the system during the run:
+
+ # echo 'hist:key=id.syscall:val=hitcount' > \
+ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
+
+ # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
+ # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active]
+
+ { id: sys_fsync [ 74] } hitcount: 1
+ { id: sys_newuname [ 63] } hitcount: 1
+ { id: sys_prctl [157] } hitcount: 1
+ { id: sys_statfs [137] } hitcount: 1
+ { id: sys_symlink [ 88] } hitcount: 1
+ { id: sys_sendmmsg [307] } hitcount: 1
+ { id: sys_semctl [ 66] } hitcount: 1
+ { id: sys_readlink [ 89] } hitcount: 3
+ { id: sys_bind [ 49] } hitcount: 3
+ { id: sys_getsockname [ 51] } hitcount: 3
+ { id: sys_unlink [ 87] } hitcount: 3
+ { id: sys_rename [ 82] } hitcount: 4
+ { id: unknown_syscall [ 58] } hitcount: 4
+ { id: sys_connect [ 42] } hitcount: 4
+ { id: sys_getpid [ 39] } hitcount: 4
+ .
+ .
+ .
+ { id: sys_rt_sigprocmask [ 14] } hitcount: 952
+ { id: sys_futex [202] } hitcount: 1534
+ { id: sys_write [ 1] } hitcount: 2689
+ { id: sys_setitimer [ 38] } hitcount: 2797
+ { id: sys_read [ 0] } hitcount: 3202
+ { id: sys_select [ 23] } hitcount: 3773
+ { id: sys_writev [ 20] } hitcount: 4531
+ { id: sys_poll [ 7] } hitcount: 8314
+ { id: sys_recvmsg [ 47] } hitcount: 13738
+ { id: sys_ioctl [ 16] } hitcount: 21843
+
+ Totals:
+ Hits: 67612
+ Entries: 72
+ Dropped: 0
+
+ The syscall counts above provide a rough overall picture of system
+ call activity on the system; we can see for example that the most
+ popular system call on this system was the 'sys_ioctl' system call.
+
+ We can use 'compound' keys to refine that number and provide some
+ further insight as to which processes exactly contribute to the
+ overall ioctl count.
+
+ The command below keeps a hitcount for every unique combination of
+ system call id and pid - the end result is essentially a table
+ that keeps a per-pid sum of system call hits. The results are
+ sorted using the system call id as the primary key, and the
+ hitcount sum as the secondary key:
+
+ # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \
+ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
+
+ # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
+ # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active]
+
+ { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1
+ { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1
+ { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1
+ { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1
+ { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2
+ { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2
+ { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2
+ { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2
+ { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2
+ { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2
+ .
+ .
+ .
+ { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12
+ { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16
+ { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808
+ { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580
+ .
+ .
+ .
+ { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3
+ { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4
+ { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6
+ { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2
+ { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4
+ { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6
+
+ Totals:
+ Hits: 31536
+ Entries: 323
+ Dropped: 0
+
+ The above list does give us a breakdown of the ioctl syscall by
+ pid, but it also gives us quite a bit more than that, which we
+ don't really care about at the moment. Since we know the syscall
+ id for sys_ioctl (16, displayed next to the sys_ioctl name), we
+ can use that to filter out all the other syscalls:
+
+ # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \
+ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger
+
+ # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist
+ # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active]
+
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1
+ { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1
+ .
+ .
+ .
+ { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45
+ { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48
+ { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48
+ { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66
+ { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674
+ { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443
+
+ Totals:
+ Hits: 101162
+ Entries: 103
+ Dropped: 0
+
+ The above output shows that 'compiz' and 'Xorg' are far and away
+ the heaviest ioctl callers (which might lead to questions about
+ whether they really need to be making all those calls and to
+ possible avenues for further investigation.)
+
+ The compound key examples used a key and a sum value (hitcount) to
+ sort the output, but we can just as easily use two keys instead.
+ Here's an example where we use a compound key composed of the the
+ common_pid and size event fields. Sorting with pid as the primary
+ key and 'size' as the secondary key allows us to display an
+ ordered summary of the recvfrom sizes, with counts, received by
+ each process:
+
+ # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \
+ /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger
+
+ # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist
+ # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active]
+
+ { common_pid: smbd [ 784], size: 4 } hitcount: 1
+ { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672
+ { common_pid: postgres [ 1796], size: 1000 } hitcount: 6
+ { common_pid: postgres [ 1867], size: 1000 } hitcount: 10
+ { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2
+ { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1
+ { common_pid: compiz [ 2994], size: 8 } hitcount: 1
+ { common_pid: compiz [ 2994], size: 20 } hitcount: 11
+ { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2
+ { common_pid: firefox [ 8817], size: 4 } hitcount: 1
+ { common_pid: firefox [ 8817], size: 8 } hitcount: 5
+ { common_pid: firefox [ 8817], size: 588 } hitcount: 2
+ { common_pid: firefox [ 8817], size: 628 } hitcount: 1
+ { common_pid: firefox [ 8817], size: 6944 } hitcount: 1
+ { common_pid: firefox [ 8817], size: 408880 } hitcount: 2
+ { common_pid: firefox [ 8822], size: 8 } hitcount: 2
+ { common_pid: firefox [ 8822], size: 160 } hitcount: 2
+ { common_pid: firefox [ 8822], size: 320 } hitcount: 2
+ { common_pid: firefox [ 8822], size: 352 } hitcount: 1
+ .
+ .
+ .
+ { common_pid: pool [ 8923], size: 1960 } hitcount: 10
+ { common_pid: pool [ 8923], size: 2048 } hitcount: 10
+ { common_pid: pool [ 8924], size: 1960 } hitcount: 10
+ { common_pid: pool [ 8924], size: 2048 } hitcount: 10
+ { common_pid: pool [ 8928], size: 1964 } hitcount: 4
+ { common_pid: pool [ 8928], size: 1965 } hitcount: 2
+ { common_pid: pool [ 8928], size: 2048 } hitcount: 6
+ { common_pid: pool [ 8929], size: 1982 } hitcount: 1
+ { common_pid: pool [ 8929], size: 2048 } hitcount: 1
+
+ Totals:
+ Hits: 2016
+ Entries: 224
+ Dropped: 0
+
+ The above example also illustrates the fact that although a compound
+ key is treated as a single entity for hashing purposes, the sub-keys
+ it's composed of can be accessed independently.
+
+ The next example uses a string field as the hash key and
+ demonstrates how you can manually pause and continue a hist trigger.
+ In this example, we'll aggregate fork counts and don't expect a
+ large number of entries in the hash table, so we'll drop it to a
+ much smaller number, say 256:
+
+ # echo 'hist:key=child_comm:val=hitcount:size=256' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
+
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
+ # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active]
+
+ { child_comm: dconf worker } hitcount: 1
+ { child_comm: ibus-daemon } hitcount: 1
+ { child_comm: whoopsie } hitcount: 1
+ { child_comm: smbd } hitcount: 1
+ { child_comm: gdbus } hitcount: 1
+ { child_comm: kthreadd } hitcount: 1
+ { child_comm: dconf worker } hitcount: 1
+ { child_comm: evolution-alarm } hitcount: 2
+ { child_comm: Socket Thread } hitcount: 2
+ { child_comm: postgres } hitcount: 2
+ { child_comm: bash } hitcount: 3
+ { child_comm: compiz } hitcount: 3
+ { child_comm: evolution-sourc } hitcount: 4
+ { child_comm: dhclient } hitcount: 4
+ { child_comm: pool } hitcount: 5
+ { child_comm: nm-dispatcher.a } hitcount: 8
+ { child_comm: firefox } hitcount: 8
+ { child_comm: dbus-daemon } hitcount: 8
+ { child_comm: glib-pacrunner } hitcount: 10
+ { child_comm: evolution } hitcount: 23
+
+ Totals:
+ Hits: 89
+ Entries: 20
+ Dropped: 0
+
+ If we want to pause the hist trigger, we can simply append :pause to
+ the command that started the trigger. Notice that the trigger info
+ displays as [paused]:
+
+ # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
+
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
+ # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused]
+
+ { child_comm: dconf worker } hitcount: 1
+ { child_comm: kthreadd } hitcount: 1
+ { child_comm: dconf worker } hitcount: 1
+ { child_comm: gdbus } hitcount: 1
+ { child_comm: ibus-daemon } hitcount: 1
+ { child_comm: Socket Thread } hitcount: 2
+ { child_comm: evolution-alarm } hitcount: 2
+ { child_comm: smbd } hitcount: 2
+ { child_comm: bash } hitcount: 3
+ { child_comm: whoopsie } hitcount: 3
+ { child_comm: compiz } hitcount: 3
+ { child_comm: evolution-sourc } hitcount: 4
+ { child_comm: pool } hitcount: 5
+ { child_comm: postgres } hitcount: 6
+ { child_comm: firefox } hitcount: 8
+ { child_comm: dhclient } hitcount: 10
+ { child_comm: emacs } hitcount: 12
+ { child_comm: dbus-daemon } hitcount: 20
+ { child_comm: nm-dispatcher.a } hitcount: 20
+ { child_comm: evolution } hitcount: 35
+ { child_comm: glib-pacrunner } hitcount: 59
+
+ Totals:
+ Hits: 199
+ Entries: 21
+ Dropped: 0
+
+ To manually continue having the trigger aggregate events, append
+ :cont instead. Notice that the trigger info displays as [active]
+ again, and the data has changed:
+
+ # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
+
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
+ # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active]
+
+ { child_comm: dconf worker } hitcount: 1
+ { child_comm: dconf worker } hitcount: 1
+ { child_comm: kthreadd } hitcount: 1
+ { child_comm: gdbus } hitcount: 1
+ { child_comm: ibus-daemon } hitcount: 1
+ { child_comm: Socket Thread } hitcount: 2
+ { child_comm: evolution-alarm } hitcount: 2
+ { child_comm: smbd } hitcount: 2
+ { child_comm: whoopsie } hitcount: 3
+ { child_comm: compiz } hitcount: 3
+ { child_comm: evolution-sourc } hitcount: 4
+ { child_comm: bash } hitcount: 5
+ { child_comm: pool } hitcount: 5
+ { child_comm: postgres } hitcount: 6
+ { child_comm: firefox } hitcount: 8
+ { child_comm: dhclient } hitcount: 11
+ { child_comm: emacs } hitcount: 12
+ { child_comm: dbus-daemon } hitcount: 22
+ { child_comm: nm-dispatcher.a } hitcount: 22
+ { child_comm: evolution } hitcount: 35
+ { child_comm: glib-pacrunner } hitcount: 59
+
+ Totals:
+ Hits: 206
+ Entries: 21
+ Dropped: 0
+
+ The previous example showed how to start and stop a hist trigger by
+ appending 'pause' and 'continue' to the hist trigger command. A
+ hist trigger can also be started in a paused state by initially
+ starting the trigger with ':pause' appended. This allows you to
+ start the trigger only when you're ready to start collecting data
+ and not before. For example, you could start the trigger in a
+ paused state, then unpause it and do something you want to measure,
+ then pause the trigger again when done.
+
+ Of course, doing this manually can be difficult and error-prone, but
+ it is possible to automatically start and stop a hist trigger based
+ on some condition, via the enable_hist and disable_hist triggers.
+
+ For example, suppose we wanted to take a look at the relative
+ weights in terms of skb length for each callpath that leads to a
+ netif_receieve_skb event when downloading a decent-sized file using
+ wget.
+
+ First we set up an initially paused stacktrace trigger on the
+ netif_receive_skb event:
+
+ # echo 'hist:key=stacktrace:vals=len:pause' > \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+
+ Next, we set up an 'enable_hist' trigger on the sched_process_exec
+ event, with an 'if filename==/usr/bin/wget' filter. The effect of
+ this new trigger is that it will 'unpause' the hist trigger we just
+ set up on netif_receive_skb if and only if it sees a
+ sched_process_exec event with a filename of '/usr/bin/wget'. When
+ that happens, all netif_receive_skb events are aggregated into a
+ hash table keyed on stacktrace:
+
+ # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
+
+ The aggregation continues until the netif_receive_skb is paused
+ again, which is what the following disable_hist event does by
+ creating a similar setup on the sched_process_exit event, using the
+ filter 'comm==wget':
+
+ # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
+
+ Whenever a process exits and the comm field of the disable_hist
+ trigger filter matches 'comm==wget', the netif_receive_skb hist
+ trigger is disabled.
+
+ The overall effect is that netif_receive_skb events are aggregated
+ into the hash table for only the duration of the wget. Executing a
+ wget command and then listing the 'hist' file will display the
+ output generated by the wget command:
+
+ $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz
+
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
+ # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused]
+
+ { stacktrace:
+ __netif_receive_skb_core+0x46d/0x990
+ __netif_receive_skb+0x18/0x60
+ netif_receive_skb_internal+0x23/0x90
+ napi_gro_receive+0xc8/0x100
+ ieee80211_deliver_skb+0xd6/0x270 [mac80211]
+ ieee80211_rx_handlers+0xccf/0x22f0 [mac80211]
+ ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211]
+ ieee80211_rx+0x31d/0x900 [mac80211]
+ iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm]
+ iwl_rx_dispatch+0x8e/0xf0 [iwldvm]
+ iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi]
+ irq_thread_fn+0x20/0x50
+ irq_thread+0x11f/0x150
+ kthread+0xd2/0xf0
+ ret_from_fork+0x42/0x70
+ } hitcount: 85 len: 28884
+ { stacktrace:
+ __netif_receive_skb_core+0x46d/0x990
+ __netif_receive_skb+0x18/0x60
+ netif_receive_skb_internal+0x23/0x90
+ napi_gro_complete+0xa4/0xe0
+ dev_gro_receive+0x23a/0x360
+ napi_gro_receive+0x30/0x100
+ ieee80211_deliver_skb+0xd6/0x270 [mac80211]
+ ieee80211_rx_handlers+0xccf/0x22f0 [mac80211]
+ ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211]
+ ieee80211_rx+0x31d/0x900 [mac80211]
+ iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm]
+ iwl_rx_dispatch+0x8e/0xf0 [iwldvm]
+ iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi]
+ irq_thread_fn+0x20/0x50
+ irq_thread+0x11f/0x150
+ kthread+0xd2/0xf0
+ } hitcount: 98 len: 664329
+ { stacktrace:
+ __netif_receive_skb_core+0x46d/0x990
+ __netif_receive_skb+0x18/0x60
+ process_backlog+0xa8/0x150
+ net_rx_action+0x15d/0x340
+ __do_softirq+0x114/0x2c0
+ do_softirq_own_stack+0x1c/0x30
+ do_softirq+0x65/0x70
+ __local_bh_enable_ip+0xb5/0xc0
+ ip_finish_output+0x1f4/0x840
+ ip_output+0x6b/0xc0
+ ip_local_out_sk+0x31/0x40
+ ip_send_skb+0x1a/0x50
+ udp_send_skb+0x173/0x2a0
+ udp_sendmsg+0x2bf/0x9f0
+ inet_sendmsg+0x64/0xa0
+ sock_sendmsg+0x3d/0x50
+ } hitcount: 115 len: 13030
+ { stacktrace:
+ __netif_receive_skb_core+0x46d/0x990
+ __netif_receive_skb+0x18/0x60
+ netif_receive_skb_internal+0x23/0x90
+ napi_gro_complete+0xa4/0xe0
+ napi_gro_flush+0x6d/0x90
+ iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi]
+ irq_thread_fn+0x20/0x50
+ irq_thread+0x11f/0x150
+ kthread+0xd2/0xf0
+ ret_from_fork+0x42/0x70
+ } hitcount: 934 len: 5512212
+
+ Totals:
+ Hits: 1232
+ Entries: 4
+ Dropped: 0
+
+ The above shows all the netif_receive_skb callpaths and their total
+ lengths for the duration of the wget command.
+
+ The 'clear' hist trigger param can be used to clear the hash table.
+ Suppose we wanted to try another run of the previous example but
+ this time also wanted to see the complete list of events that went
+ into the histogram. In order to avoid having to set everything up
+ again, we can just clear the histogram first:
+
+ # echo 'hist:key=stacktrace:vals=len:clear' >> \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+
+ Just to verify that it is in fact cleared, here's what we now see in
+ the hist file:
+
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
+ # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused]
+
+ Totals:
+ Hits: 0
+ Entries: 0
+ Dropped: 0
+
+ Since we want to see the detailed list of every netif_receive_skb
+ event occurring during the new run, which are in fact the same
+ events being aggregated into the hash table, we add some additional
+ 'enable_event' events to the triggering sched_process_exec and
+ sched_process_exit events as such:
+
+ # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
+
+ # echo 'disable_event:net:netif_receive_skb if comm==wget' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
+
+ If you read the trigger files for the sched_process_exec and
+ sched_process_exit triggers, you should see two triggers for each:
+ one enabling/disabling the hist aggregation and the other
+ enabling/disabling the logging of events:
+
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger
+ enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget
+ enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget
+
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger
+ enable_event:net:netif_receive_skb:unlimited if comm==wget
+ disable_hist:net:netif_receive_skb:unlimited if comm==wget
+
+ In other words, whenever either of the sched_process_exec or
+ sched_process_exit events is hit and matches 'wget', it enables or
+ disables both the histogram and the event log, and what you end up
+ with is a hash table and set of events just covering the specified
+ duration. Run the wget command again:
+
+ $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz
+
+ Displaying the 'hist' file should show something similar to what you
+ saw in the last run, but this time you should also see the
+ individual events in the trace file:
+
+ # cat /sys/kernel/debug/tracing/trace
+
+ # tracer: nop
+ #
+ # entries-in-buffer/entries-written: 183/1426 #P:4
+ #
+ # _-----=> irqs-off
+ # / _----=> need-resched
+ # | / _---=> hardirq/softirq
+ # || / _--=> preempt-depth
+ # ||| / delay
+ # TASK-PID CPU# |||| TIMESTAMP FUNCTION
+ # | | | |||| | |
+ wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60
+ wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60
+ dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130
+ dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138
+ ##### CPU 2 buffer started ####
+ irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948
+ irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500
+ irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948
+ irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948
+ irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500
+ .
+ .
+ .
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 17/23] tracing: Add support for multiple hist triggers per event
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (15 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 16/23] tracing: Add 'hist' trigger Documentation Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 18/23] tracing: Add support for named triggers Tom Zanussi
` (5 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to define any number of hist triggers per trace event.
Any number of hist triggers may be added for a given event, which may
differ by key, value, or filter.
Reading the event's 'hist' file will display the output of all the
hist triggers defined on an event concatenated in the order they were
defined.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
Documentation/trace/events.txt | 154 +++++++++++++++++++++++++++++++++--
kernel/trace/trace.c | 8 +-
kernel/trace/trace_events_hist.c | 172 +++++++++++++++++++++++++++++++--------
3 files changed, 293 insertions(+), 41 deletions(-)
diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt
index db223e8..cc02167 100644
--- a/Documentation/trace/events.txt
+++ b/Documentation/trace/events.txt
@@ -550,12 +550,14 @@ The following commands are supported:
'hist' triggers add a 'hist' file to each event's subdirectory.
Reading the 'hist' file for the event will dump the hash table in
- its entirety to stdout. Each printed hash table entry is a simple
- list of the keys and values comprising the entry; keys are printed
- first and are delineated by curly braces, and are followed by the
- set of value fields for the entry. By default, numeric fields are
- displayed as base-10 integers. This can be modified by appending
- any of the following modifiers to the field name:
+ its entirety to stdout. If there are multiple hist triggers
+ attached to an event, there will be a table for each trigger in the
+ output. Each printed hash table entry is a simple list of the keys
+ and values comprising the entry; keys are printed first and are
+ delineated by curly braces, and are followed by the set of value
+ fields for the entry. By default, numeric fields are displayed as
+ base-10 integers. This can be modified by appending any of the
+ following modifiers to the field name:
.hex display a number as a hex value
.sym display an address as a symbol
@@ -1667,3 +1669,143 @@ The following commands are supported:
.
.
.
+
+ The following example demonstrates how multiple hist triggers can be
+ attached to a given event. This capability can be useful for
+ creating a set of different summaries derived from the same set of
+ events, or for comparing the effects of different filters, among
+ other things.
+
+ # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+ # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+ # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+ # echo 'hist:keys=skbaddr.hex:vals=len' >> \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+ # echo 'hist:keys=len:vals=common_preempt_count' >> \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+
+ The above set of commands create four triggers differing only in
+ their filters, along with a completely different though fairly
+ nonsensical trigger. Note that in order to append multiple hist
+ triggers to the same file, you should use the '>>' operator to
+ append them ('>' will also add the new hist trigger, but will remove
+ any existing hist triggers beforehand).
+
+ Displaying the contents of the 'hist' file for the event shows the
+ contents of all five histograms:
+
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist
+
+ # event histogram
+ #
+ # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active]
+ #
+
+ { len: 176 } hitcount: 1 common_preempt_count: 0
+ { len: 223 } hitcount: 1 common_preempt_count: 0
+ { len: 4854 } hitcount: 1 common_preempt_count: 0
+ { len: 395 } hitcount: 1 common_preempt_count: 0
+ { len: 177 } hitcount: 1 common_preempt_count: 0
+ { len: 446 } hitcount: 1 common_preempt_count: 0
+ { len: 1601 } hitcount: 1 common_preempt_count: 0
+ .
+ .
+ .
+ { len: 1280 } hitcount: 66 common_preempt_count: 0
+ { len: 116 } hitcount: 81 common_preempt_count: 40
+ { len: 708 } hitcount: 112 common_preempt_count: 0
+ { len: 46 } hitcount: 221 common_preempt_count: 0
+ { len: 1264 } hitcount: 458 common_preempt_count: 0
+
+ Totals:
+ Hits: 1428
+ Entries: 147
+ Dropped: 0
+
+
+ # event histogram
+ #
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
+ #
+
+ { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130
+ { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280
+ { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280
+ { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115
+ { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115
+ { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46
+ { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118
+ { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60
+ { skbaddr: ffff880100065900 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116
+ { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280
+ { skbaddr: ffff880100064700 } hitcount: 1 len: 365
+ { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60
+ .
+ .
+ .
+ { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677
+ { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052
+ { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589
+ { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326
+ { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678
+ { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678
+ { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589
+ { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307
+ { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032
+
+ Totals:
+ Hits: 1451
+ Entries: 318
+ Dropped: 0
+
+
+ # event histogram
+ #
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active]
+ #
+
+
+ Totals:
+ Hits: 0
+ Entries: 0
+ Dropped: 0
+
+
+ # event histogram
+ #
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active]
+ #
+
+ { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212
+ { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212
+ { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212
+ { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492
+ { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212
+ { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212
+ { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854
+ { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636
+ { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924
+ { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356
+ { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420
+ { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996
+
+ Totals:
+ Hits: 14
+ Entries: 12
+ Dropped: 0
+
+
+ # event histogram
+ #
+ # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active]
+ #
+
+
+ Totals:
+ Hits: 0
+ Entries: 0
+ Dropped: 0
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8834fd2..7385bea 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3847,9 +3847,11 @@ static const char readme_msg[] =
"\t sort field. The 'size' parameter can be used to specify more\n"
"\t or fewer than the default 2048 entries for the hashtable size.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
- "\t table in its entirety to stdout. The default format used to\n"
- "\t display a given field can be modified by appending any of the\n"
- "\t following modifiers to the field name, as applicable:\n\n"
+ "\t table in its entirety to stdout. If there are multiple hist\n"
+ "\t triggers attached to an event, there will be a table for each\n"
+ "\t trigger in the output. The default format used to display a\n"
+ "\t given field can be modified by appending any of the following\n"
+ "\t modifiers to the field name, as applicable:\n\n"
"\t .hex display a number as a hex value\n"
"\t .sym display an address as a symbol\n"
"\t .sym-offset display an address as a symbol and offset\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index c3ddde1..a7036ff 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1026,33 +1026,18 @@ static int print_entries(struct seq_file *m,
return n_entries;
}
-static int hist_show(struct seq_file *m, void *v)
+static void hist_trigger_show(struct seq_file *m,
+ struct event_trigger_data *data, int n)
{
- struct event_trigger_data *test, *data = NULL;
- struct trace_event_file *event_file;
struct hist_trigger_data *hist_data;
int n_entries, ret = 0;
- mutex_lock(&event_mutex);
-
- event_file = event_file_data(m->private);
- if (unlikely(!event_file)) {
- ret = -ENODEV;
- goto out_unlock;
- }
-
- list_for_each_entry_rcu(test, &event_file->triggers, list) {
- if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
- data = test;
- break;
- }
- }
- if (!data)
- goto out_unlock;
+ if (n > 0)
+ seq_puts(m, "\n\n");
seq_puts(m, "# event histogram\n#\n# trigger info: ");
data->ops->print(m, data->ops, data);
- seq_puts(m, "\n");
+ seq_puts(m, "#\n\n");
hist_data = data->private_data;
n_entries = print_entries(m, hist_data);
@@ -1064,6 +1049,27 @@ static int hist_show(struct seq_file *m, void *v)
seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
(u64)atomic64_read(&hist_data->map->hits),
n_entries, (u64)atomic64_read(&hist_data->map->drops));
+}
+
+static int hist_show(struct seq_file *m, void *v)
+{
+ struct event_trigger_data *data;
+ struct trace_event_file *event_file;
+ int n = 0, ret = 0;
+
+ mutex_lock(&event_mutex);
+
+ event_file = event_file_data(m->private);
+ if (unlikely(!event_file)) {
+ ret = -ENODEV;
+ goto out_unlock;
+ }
+
+ list_for_each_entry_rcu(data, &event_file->triggers, list) {
+ if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
+ hist_trigger_show(m, data, n++);
+ }
+
out_unlock:
mutex_unlock(&event_mutex);
@@ -1227,6 +1233,54 @@ static void hist_clear(struct event_trigger_data *data)
data->paused = paused;
}
+static bool hist_trigger_match(struct event_trigger_data *data,
+ struct event_trigger_data *data_test)
+{
+ struct tracing_map_sort_key *sort_key, *sort_key_test;
+ struct hist_trigger_data *hist_data, *hist_data_test;
+ struct hist_field *key_field, *key_field_test;
+ unsigned int i;
+
+ hist_data = data->private_data;
+ hist_data_test = data_test->private_data;
+
+ if (hist_data->n_vals != hist_data_test->n_vals ||
+ hist_data->n_fields != hist_data_test->n_fields ||
+ hist_data->n_sort_keys != hist_data_test->n_sort_keys)
+ return false;
+
+ if ((data->filter_str && !data_test->filter_str) ||
+ (!data->filter_str && data_test->filter_str))
+ return false;
+
+ for_each_hist_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+ key_field_test = hist_data_test->fields[i];
+
+ if (key_field->flags != key_field_test->flags)
+ return false;
+ if (key_field->field != key_field_test->field)
+ return false;
+ if (key_field->offset != key_field_test->offset)
+ return false;
+ }
+
+ for (i = 0; i < hist_data->n_sort_keys; i++) {
+ sort_key = &hist_data->sort_keys[i];
+ sort_key_test = &hist_data_test->sort_keys[i];
+
+ if (sort_key->field_idx != sort_key_test->field_idx ||
+ sort_key->descending != sort_key_test->descending)
+ return false;
+ }
+
+ if (data->filter_str &&
+ (strcmp(data->filter_str, data_test->filter_str) != 0))
+ return false;
+
+ return true;
+}
+
static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
@@ -1237,6 +1291,8 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ if (!hist_trigger_match(data, test))
+ continue;
if (hist_data->attrs->pause)
test->paused = true;
else if (hist_data->attrs->cont)
@@ -1276,6 +1332,44 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
return ret;
}
+static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
+ struct event_trigger_data *data,
+ struct trace_event_file *file)
+{
+ struct event_trigger_data *test;
+ bool unregistered = false;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ if (!hist_trigger_match(data, test))
+ continue;
+ unregistered = true;
+ list_del_rcu(&test->list);
+ trace_event_trigger_enable_disable(file, 0);
+ update_cond_flag(file);
+ break;
+ }
+ }
+
+ if (unregistered && test->ops->free)
+ test->ops->free(test->ops, test);
+}
+
+static void hist_unreg_all(struct trace_event_file *file)
+{
+ struct event_trigger_data *test;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ list_del_rcu(&test->list);
+ trace_event_trigger_enable_disable(file, 0);
+ update_cond_flag(file);
+ if (test->ops->free)
+ test->ops->free(test->ops, test);
+ }
+ }
+}
+
static int event_hist_trigger_func(struct event_command *cmd_ops,
struct trace_event_file *file,
char *glob, char *cmd, char *param)
@@ -1325,22 +1419,19 @@ static int event_hist_trigger_func(struct event_command *cmd_ops,
trigger_data->private_data = hist_data;
+ /* if param is non-empty, it's supposed to be a filter */
+ if (param && cmd_ops->set_filter) {
+ ret = cmd_ops->set_filter(param, trigger_data, file);
+ if (ret < 0)
+ goto out_free;
+ }
+
if (glob[0] == '!') {
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
ret = 0;
goto out_free;
}
- if (!param) /* if param is non-empty, it's supposed to be a filter */
- goto out_reg;
-
- if (!cmd_ops->set_filter)
- goto out_reg;
-
- ret = cmd_ops->set_filter(param, trigger_data, file);
- if (ret < 0)
- goto out_free;
- out_reg:
ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
/*
* The above returns on success the # of triggers registered,
@@ -1373,7 +1464,8 @@ static struct event_command trigger_hist_cmd = {
.flags = EVENT_CMD_FL_NEEDS_REC,
.func = event_hist_trigger_func,
.reg = hist_register_trigger,
- .unreg = unregister_trigger,
+ .unreg = hist_unregister_trigger,
+ .unreg_all = hist_unreg_all,
.get_trigger_ops = event_hist_get_trigger_ops,
.set_filter = set_trigger_filter,
};
@@ -1400,7 +1492,6 @@ hist_enable_trigger(struct event_trigger_data *data, void *rec)
test->paused = false;
else
test->paused = true;
- break;
}
}
}
@@ -1463,12 +1554,28 @@ hist_enable_get_trigger_ops(char *cmd, char *param)
return ops;
}
+static void hist_enable_unreg_all(struct trace_event_file *file)
+{
+ struct event_trigger_data *test;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
+ list_del_rcu(&test->list);
+ update_cond_flag(file);
+ trace_event_trigger_enable_disable(file, 0);
+ if (test->ops->free)
+ test->ops->free(test->ops, test);
+ }
+ }
+}
+
static struct event_command trigger_hist_enable_cmd = {
.name = ENABLE_HIST_STR,
.trigger_type = ETT_HIST_ENABLE,
.func = event_enable_trigger_func,
.reg = event_enable_register_trigger,
.unreg = event_enable_unregister_trigger,
+ .unreg_all = hist_enable_unreg_all,
.get_trigger_ops = hist_enable_get_trigger_ops,
.set_filter = set_trigger_filter,
};
@@ -1479,6 +1586,7 @@ static struct event_command trigger_hist_disable_cmd = {
.func = event_enable_trigger_func,
.reg = event_enable_register_trigger,
.unreg = event_enable_unregister_trigger,
+ .unreg_all = hist_enable_unreg_all,
.get_trigger_ops = hist_enable_get_trigger_ops,
.set_filter = set_trigger_filter,
};
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 18/23] tracing: Add support for named triggers
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (16 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 17/23] tracing: Add support for multiple hist triggers per event Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 19/23] tracing: Add support for named hist triggers Tom Zanussi
` (4 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Named triggers are sets of triggers that share a common set of trigger
data. An example of functionality that could benefit from this type
of capability would be a set of inlined probes that would each
contribute event counts, for example, to a shared counter data
structure.
The first named trigger registered with a given name owns the common
trigger data that the others subsequently registered with the same
name will reference. The functions defined here allow users to add,
delete, and find named triggers.
It also adds functions to pause and unpause named triggers; since
named triggers act upon common data, they should also be paused and
unpaused as a group.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace.h | 13 ++++
kernel/trace/trace_events_trigger.c | 143 ++++++++++++++++++++++++++++++++++++
2 files changed, 156 insertions(+)
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 973427e..8ca697a 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1183,7 +1183,11 @@ struct event_trigger_data {
char *filter_str;
void *private_data;
bool paused;
+ bool paused_tmp;
struct list_head list;
+ char *name;
+ struct list_head named_list;
+ struct event_trigger_data *named_data;
};
/* Avoid typos */
@@ -1226,6 +1230,15 @@ extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
extern int set_trigger_filter(char *filter_str,
struct event_trigger_data *trigger_data,
struct trace_event_file *file);
+extern struct event_trigger_data *find_named_trigger(const char *name);
+extern bool is_named_trigger(struct event_trigger_data *test);
+extern int save_named_trigger(const char *name,
+ struct event_trigger_data *data);
+extern void del_named_trigger(struct event_trigger_data *data);
+extern void pause_named_trigger(struct event_trigger_data *data);
+extern void unpause_named_trigger(struct event_trigger_data *data);
+extern void set_named_trigger_data(struct event_trigger_data *data,
+ struct event_trigger_data *named_data);
extern int register_event_command(struct event_command *cmd);
extern int unregister_event_command(struct event_command *cmd);
extern int register_trigger_hist_enable_disable_cmds(void);
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 03109f1..02354ff 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -645,6 +645,7 @@ event_trigger_callback(struct event_command *cmd_ops,
trigger_data->ops = trigger_ops;
trigger_data->cmd_ops = cmd_ops;
INIT_LIST_HEAD(&trigger_data->list);
+ INIT_LIST_HEAD(&trigger_data->named_list);
if (glob[0] == '!') {
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
@@ -768,6 +769,148 @@ int set_trigger_filter(char *filter_str,
return ret;
}
+static LIST_HEAD(named_triggers);
+
+/**
+ * find_named_trigger - Find the common named trigger associated with @name
+ * @name: The name of the set of named triggers to find the common data for
+ *
+ * Named triggers are sets of triggers that share a common set of
+ * trigger data. The first named trigger registered with a given name
+ * owns the common trigger data that the others subsequently
+ * registered with the same name will reference. This function
+ * returns the common trigger data associated with that first
+ * registered instance.
+ *
+ * Return: the common trigger data for the given named trigger on
+ * success, NULL otherwise.
+ */
+struct event_trigger_data *find_named_trigger(const char *name)
+{
+ struct event_trigger_data *data;
+
+ if (!name)
+ return NULL;
+
+ list_for_each_entry(data, &named_triggers, named_list) {
+ if (data->named_data)
+ continue;
+ if (strcmp(data->name, name) == 0)
+ return data;
+ }
+
+ return NULL;
+}
+
+/**
+ * is_named_trigger - determine if a given trigger is a named trigger
+ * @test: The trigger data to test
+ *
+ * Return: true if 'test' is a named trigger, false otherwise.
+ */
+bool is_named_trigger(struct event_trigger_data *test)
+{
+ struct event_trigger_data *data;
+
+ list_for_each_entry(data, &named_triggers, named_list) {
+ if (test == data)
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * save_named_trigger - save the trigger in the named trigger list
+ * @name: The name of the named trigger set
+ * @data: The trigger data to save
+ *
+ * Return: 0 if successful, negative error otherwise.
+ */
+int save_named_trigger(const char *name, struct event_trigger_data *data)
+{
+ data->name = kstrdup(name, GFP_KERNEL);
+ if (!data->name)
+ return -ENOMEM;
+
+ list_add(&data->named_list, &named_triggers);
+
+ return 0;
+}
+
+/**
+ * del_named_trigger - delete a trigger from the named trigger list
+ * @data: The trigger data to delete
+ */
+void del_named_trigger(struct event_trigger_data *data)
+{
+ kfree(data->name);
+ data->name = NULL;
+
+ list_del(&data->named_list);
+}
+
+static void __pause_named_trigger(struct event_trigger_data *data, bool pause)
+{
+ struct event_trigger_data *test;
+
+ list_for_each_entry(test, &named_triggers, named_list) {
+ if (strcmp(test->name, data->name) == 0) {
+ if (pause) {
+ test->paused_tmp = test->paused;
+ test->paused = true;
+ } else {
+ test->paused = test->paused_tmp;
+ }
+ }
+ }
+}
+
+/**
+ * pause_named_trigger - Pause all named triggers with the same name
+ * @data: The trigger data of a named trigger to pause
+ *
+ * Pauses a named trigger along with all other triggers having the
+ * same name. Because named triggers share a common set of data,
+ * pausing only one is meaningless, so pausing one named trigger needs
+ * to pause all triggers with the same name.
+ */
+void pause_named_trigger(struct event_trigger_data *data)
+{
+ __pause_named_trigger(data, true);
+}
+
+/**
+ * unpause_named_trigger - Un-pause all named triggers with the same name
+ * @data: The trigger data of a named trigger to unpause
+ *
+ * Un-pauses a named trigger along with all other triggers having the
+ * same name. Because named triggers share a common set of data,
+ * unpausing only one is meaningless, so unpausing one named trigger
+ * needs to unpause all triggers with the same name.
+ */
+void unpause_named_trigger(struct event_trigger_data *data)
+{
+ __pause_named_trigger(data, false);
+}
+
+/**
+ * set_named_trigger_data - Associate common named trigger data
+ * @data: The trigger data of a named trigger to unpause
+ *
+ * Named triggers are sets of triggers that share a common set of
+ * trigger data. The first named trigger registered with a given name
+ * owns the common trigger data that the others subsequently
+ * registered with the same name will reference. This function
+ * associates the common trigger data from the first trigger with the
+ * given trigger.
+ */
+void set_named_trigger_data(struct event_trigger_data *data,
+ struct event_trigger_data *named_data)
+{
+ data->named_data = named_data;
+}
+
static void
traceon_trigger(struct event_trigger_data *data, void *rec)
{
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 19/23] tracing: Add support for named hist triggers
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (17 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 18/23] tracing: Add support for named triggers Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 20/23] kselftests/ftrace : Add event trigger testcases Tom Zanussi
` (3 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
Allow users to define 'named' hist triggers. All triggers created
with the same 'name=xxx' option will update the same shared histogram
data.
This expands the hist trigger syntax from this:
# echo hist:keys=xxx ... [ if filter] > event/trigger
to this:
# echo hist:name=xxx:keys=xxx ... [ if filter] > event/trigger
Named histograms must use a 'compatible' set of keys and values, which
means each event added to a set of named triggers must have the same
names and types.
Reading the 'hist' file of any of the participating events will
produce the same output as any other participating event, which is to
be expected since they share the same data.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
Documentation/trace/events.txt | 274 +++++++++++++++++++++++++++++++++++++--
kernel/trace/trace.c | 14 +-
kernel/trace/trace_events_hist.c | 148 ++++++++++++++++++---
3 files changed, 407 insertions(+), 29 deletions(-)
diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt
index cc02167..08d74d7 100644
--- a/Documentation/trace/events.txt
+++ b/Documentation/trace/events.txt
@@ -524,7 +524,7 @@ The following commands are supported:
hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>]
[:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue]
- [:clear] [if <filter>]
+ [:clear][:name=histname1] [if <filter>]
When a matching event is hit, an entry is added to a hash table
using the key(s) and value(s) named. Keys and values correspond to
@@ -546,18 +546,28 @@ The following commands are supported:
specified by the 'sort' keyword. If more than one field is
specified, the result will be a 'sort within a sort': the first key
is taken to be the primary sort key and the second the secondary
- key.
+ key. If a hist trigger is given a name using the 'name' parameter,
+ its histogram data will be shared with other triggers of the same
+ name, and trigger hits will update this common data. Only triggers
+ with 'compatible' fields can be combined in this way; triggers are
+ 'compatible' if the fields named in the trigger share the same
+ number and type of fields and those fields also have the same names.
+ Note that any two events always share the compatible 'hitcount' and
+ 'stacktrace' fields and can therefore be combined using those
+ fields, however pointless that may be.
'hist' triggers add a 'hist' file to each event's subdirectory.
Reading the 'hist' file for the event will dump the hash table in
its entirety to stdout. If there are multiple hist triggers
attached to an event, there will be a table for each trigger in the
- output. Each printed hash table entry is a simple list of the keys
- and values comprising the entry; keys are printed first and are
- delineated by curly braces, and are followed by the set of value
- fields for the entry. By default, numeric fields are displayed as
- base-10 integers. This can be modified by appending any of the
- following modifiers to the field name:
+ output. The table displayed for a named trigger will be the same as
+ any other instance having the same name. Each printed hash table
+ entry is a simple list of the keys and values comprising the entry;
+ keys are printed first and are delineated by curly braces, and are
+ followed by the set of value fields for the entry. By default,
+ numeric fields are displayed as base-10 integers. This can be
+ modified by appending any of the following modifiers to the field
+ name:
.hex display a number as a hex value
.sym display an address as a symbol
@@ -1809,3 +1819,251 @@ The following commands are supported:
Hits: 0
Entries: 0
Dropped: 0
+
+ Named triggers can be used to have triggers share a common set of
+ histogram data. This capability is mostly useful for combining the
+ output of events generated by tracepoints contained inside inline
+ functions, but names can be used in a hist trigger on any event.
+ For example, these two triggers when hit will update the same 'len'
+ field in the shared 'foo' histogram data:
+
+ # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \
+ /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger
+ # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
+
+ You can see that they're updating common histogram data by reading
+ each event's hist files at the same time:
+
+ # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist;
+ cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
+
+ # event histogram
+ #
+ # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
+ #
+
+ { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46
+ { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76
+ { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468
+ { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46
+ { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52
+ { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168
+ { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260
+ { skbaddr: ffff880064505000 } hitcount: 1 len: 46
+ { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32
+ { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44
+ { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168
+ { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40
+ { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40
+ { skbaddr: ffff880064505f00 } hitcount: 1 len: 174
+ { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160
+ { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76
+ { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32
+ { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988
+ { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46
+ { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44
+ { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676
+ { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107
+ { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92
+ { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142
+ { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220
+ { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92
+ { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92
+ { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675
+ { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138
+ { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138
+ { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184
+ { skbaddr: ffff880064504400 } hitcount: 4 len: 184
+ { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184
+ { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230
+ { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196
+ { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276
+ { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276
+
+ Totals:
+ Hits: 81
+ Entries: 42
+ Dropped: 0
+ # event histogram
+ #
+ # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active]
+ #
+
+ { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46
+ { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76
+ { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468
+ { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46
+ { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52
+ { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168
+ { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260
+ { skbaddr: ffff880064505000 } hitcount: 1 len: 46
+ { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32
+ { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44
+ { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168
+ { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40
+ { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40
+ { skbaddr: ffff880064505f00 } hitcount: 1 len: 174
+ { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160
+ { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76
+ { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32
+ { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46
+ { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988
+ { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46
+ { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44
+ { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676
+ { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107
+ { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92
+ { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142
+ { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220
+ { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92
+ { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92
+ { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675
+ { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138
+ { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138
+ { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184
+ { skbaddr: ffff880064504400 } hitcount: 4 len: 184
+ { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184
+ { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230
+ { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196
+ { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276
+ { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276
+
+ Totals:
+ Hits: 81
+ Entries: 42
+ Dropped: 0
+
+ And here's an example that shows how to combine histogram data from
+ any two events even if they don't share any 'compatible' fields
+ other than 'hitcount' and 'stacktrace'. These commands create a
+ couple of triggers named 'bar' using those fields:
+
+ # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \
+ /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger
+ # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \
+ /sys/kernel/debug/tracing/events/net/netif_rx/trigger
+
+ And displaying the output of either shows some interesting if
+ somewhat confusing output:
+
+ # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist
+ # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist
+
+ # event histogram
+ #
+ # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active]
+ #
+
+ { stacktrace:
+ _do_fork+0x18e/0x330
+ kernel_thread+0x29/0x30
+ kthreadd+0x154/0x1b0
+ ret_from_fork+0x3f/0x70
+ } hitcount: 1
+ { stacktrace:
+ netif_rx_internal+0xb2/0xd0
+ netif_rx_ni+0x20/0x70
+ dev_loopback_xmit+0xaa/0xd0
+ ip_mc_output+0x126/0x240
+ ip_local_out_sk+0x31/0x40
+ igmp_send_report+0x1e9/0x230
+ igmp_timer_expire+0xe9/0x120
+ call_timer_fn+0x39/0xf0
+ run_timer_softirq+0x1e1/0x290
+ __do_softirq+0xfd/0x290
+ irq_exit+0x98/0xb0
+ smp_apic_timer_interrupt+0x4a/0x60
+ apic_timer_interrupt+0x6d/0x80
+ cpuidle_enter+0x17/0x20
+ call_cpuidle+0x3b/0x60
+ cpu_startup_entry+0x22d/0x310
+ } hitcount: 1
+ { stacktrace:
+ netif_rx_internal+0xb2/0xd0
+ netif_rx_ni+0x20/0x70
+ dev_loopback_xmit+0xaa/0xd0
+ ip_mc_output+0x17f/0x240
+ ip_local_out_sk+0x31/0x40
+ ip_send_skb+0x1a/0x50
+ udp_send_skb+0x13e/0x270
+ udp_sendmsg+0x2bf/0x980
+ inet_sendmsg+0x67/0xa0
+ sock_sendmsg+0x38/0x50
+ SYSC_sendto+0xef/0x170
+ SyS_sendto+0xe/0x10
+ entry_SYSCALL_64_fastpath+0x12/0x6a
+ } hitcount: 2
+ { stacktrace:
+ netif_rx_internal+0xb2/0xd0
+ netif_rx+0x1c/0x60
+ loopback_xmit+0x6c/0xb0
+ dev_hard_start_xmit+0x219/0x3a0
+ __dev_queue_xmit+0x415/0x4f0
+ dev_queue_xmit_sk+0x13/0x20
+ ip_finish_output2+0x237/0x340
+ ip_finish_output+0x113/0x1d0
+ ip_output+0x66/0xc0
+ ip_local_out_sk+0x31/0x40
+ ip_send_skb+0x1a/0x50
+ udp_send_skb+0x16d/0x270
+ udp_sendmsg+0x2bf/0x980
+ inet_sendmsg+0x67/0xa0
+ sock_sendmsg+0x38/0x50
+ ___sys_sendmsg+0x14e/0x270
+ } hitcount: 76
+ { stacktrace:
+ netif_rx_internal+0xb2/0xd0
+ netif_rx+0x1c/0x60
+ loopback_xmit+0x6c/0xb0
+ dev_hard_start_xmit+0x219/0x3a0
+ __dev_queue_xmit+0x415/0x4f0
+ dev_queue_xmit_sk+0x13/0x20
+ ip_finish_output2+0x237/0x340
+ ip_finish_output+0x113/0x1d0
+ ip_output+0x66/0xc0
+ ip_local_out_sk+0x31/0x40
+ ip_send_skb+0x1a/0x50
+ udp_send_skb+0x16d/0x270
+ udp_sendmsg+0x2bf/0x980
+ inet_sendmsg+0x67/0xa0
+ sock_sendmsg+0x38/0x50
+ ___sys_sendmsg+0x269/0x270
+ } hitcount: 77
+ { stacktrace:
+ netif_rx_internal+0xb2/0xd0
+ netif_rx+0x1c/0x60
+ loopback_xmit+0x6c/0xb0
+ dev_hard_start_xmit+0x219/0x3a0
+ __dev_queue_xmit+0x415/0x4f0
+ dev_queue_xmit_sk+0x13/0x20
+ ip_finish_output2+0x237/0x340
+ ip_finish_output+0x113/0x1d0
+ ip_output+0x66/0xc0
+ ip_local_out_sk+0x31/0x40
+ ip_send_skb+0x1a/0x50
+ udp_send_skb+0x16d/0x270
+ udp_sendmsg+0x2bf/0x980
+ inet_sendmsg+0x67/0xa0
+ sock_sendmsg+0x38/0x50
+ SYSC_sendto+0xef/0x170
+ } hitcount: 88
+ { stacktrace:
+ _do_fork+0x18e/0x330
+ SyS_clone+0x19/0x20
+ entry_SYSCALL_64_fastpath+0x12/0x6a
+ } hitcount: 244
+
+ Totals:
+ Hits: 489
+ Entries: 7
+ Dropped: 0
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7385bea..ce8b885 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3833,6 +3833,7 @@ static const char readme_msg[] =
"\t [:sort=<field1[,field2,...]>]\n"
"\t [:size=#entries]\n"
"\t [:pause][:continue][:clear]\n"
+ "\t [:name=histname1]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named, and the value of a\n"
@@ -3845,13 +3846,18 @@ static const char readme_msg[] =
"\t specified using the 'sort' keyword. The sort direction can\n"
"\t be modified by appending '.descending' or '.ascending' to a\n"
"\t sort field. The 'size' parameter can be used to specify more\n"
- "\t or fewer than the default 2048 entries for the hashtable size.\n\n"
+ "\t or fewer than the default 2048 entries for the hashtable size.\n"
+ "\t If a hist trigger is given a name using the 'name' parameter,\n"
+ "\t its histogram data will be shared with other triggers of the\n"
+ "\t same name, and trigger hits will update this common data.\n\n"
"\t Reading the 'hist' file for the event will dump the hash\n"
"\t table in its entirety to stdout. If there are multiple hist\n"
"\t triggers attached to an event, there will be a table for each\n"
- "\t trigger in the output. The default format used to display a\n"
- "\t given field can be modified by appending any of the following\n"
- "\t modifiers to the field name, as applicable:\n\n"
+ "\t trigger in the output. The table displayed for a named\n"
+ "\t trigger will be the same as any other instance having the\n"
+ "\t same name. The default format used to display a given field\n"
+ "\t can be modified by appending any of the following modifiers\n"
+ "\t to the field name, as applicable:\n\n"
"\t .hex display a number as a hex value\n"
"\t .sym display an address as a symbol\n"
"\t .sym-offset display an address as a symbol and offset\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index a7036ff..7c65652 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -117,6 +117,7 @@ struct hist_trigger_attrs {
char *keys_str;
char *vals_str;
char *sort_key_str;
+ char *name;
bool pause;
bool cont;
bool clear;
@@ -200,6 +201,7 @@ static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
if (!attrs)
return;
+ kfree(attrs->name);
kfree(attrs->sort_key_str);
kfree(attrs->keys_str);
kfree(attrs->vals_str);
@@ -227,6 +229,8 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
attrs->vals_str = kstrdup(str, GFP_KERNEL);
else if (strncmp(str, "sort=", strlen("sort=")) == 0)
attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
+ else if (strncmp(str, "name=", strlen("name=")) == 0)
+ attrs->name = kstrdup(str, GFP_KERNEL);
else if (strcmp(str, "pause") == 0)
attrs->pause = true;
else if ((strcmp(str, "cont") == 0) ||
@@ -1125,7 +1129,12 @@ static int event_hist_trigger_print(struct seq_file *m,
struct hist_field *key_field;
unsigned int i;
- seq_puts(m, "hist:keys=");
+ seq_puts(m, "hist:");
+
+ if (data->name)
+ seq_printf(m, "%s:", data->name);
+
+ seq_puts(m, "keys=");
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
@@ -1190,6 +1199,19 @@ static int event_hist_trigger_print(struct seq_file *m,
return 0;
}
+static int event_hist_trigger_init(struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
+{
+ struct hist_trigger_data *hist_data = data->private_data;
+
+ if (!data->ref && hist_data->attrs->name)
+ save_named_trigger(hist_data->attrs->name, data);
+
+ data->ref++;
+
+ return 0;
+}
+
static void event_hist_trigger_free(struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
@@ -1200,6 +1222,8 @@ static void event_hist_trigger_free(struct event_trigger_ops *ops,
data->ref--;
if (!data->ref) {
+ if (data->name)
+ del_named_trigger(data);
trigger_data_free(data);
destroy_hist_data(hist_data);
}
@@ -1208,10 +1232,44 @@ static void event_hist_trigger_free(struct event_trigger_ops *ops,
static struct event_trigger_ops event_hist_trigger_ops = {
.func = event_hist_trigger,
.print = event_hist_trigger_print,
- .init = event_trigger_init,
+ .init = event_hist_trigger_init,
.free = event_hist_trigger_free,
};
+static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
+{
+ data->ref++;
+
+ save_named_trigger(data->named_data->name, data);
+
+ event_hist_trigger_init(ops, data->named_data);
+
+ return 0;
+}
+
+static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
+ struct event_trigger_data *data)
+{
+ if (WARN_ON_ONCE(data->ref <= 0))
+ return;
+
+ event_hist_trigger_free(ops, data->named_data);
+
+ data->ref--;
+ if (!data->ref) {
+ del_named_trigger(data);
+ trigger_data_free(data);
+ }
+}
+
+static struct event_trigger_ops event_hist_trigger_named_ops = {
+ .func = event_hist_trigger,
+ .print = event_hist_trigger_print,
+ .init = event_hist_trigger_named_init,
+ .free = event_hist_trigger_named_free,
+};
+
static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
char *param)
{
@@ -1221,26 +1279,54 @@ static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
static void hist_clear(struct event_trigger_data *data)
{
struct hist_trigger_data *hist_data = data->private_data;
- bool paused;
- paused = data->paused;
- data->paused = true;
+ if (data->name)
+ pause_named_trigger(data);
synchronize_sched();
tracing_map_clear(hist_data->map);
- data->paused = paused;
+ if (data->name)
+ unpause_named_trigger(data);
+}
+
+static bool compatible_field(struct ftrace_event_field *field,
+ struct ftrace_event_field *test_field)
+{
+ if (field == test_field)
+ return true;
+ if (field == NULL || test_field == NULL)
+ return false;
+ if (strcmp(field->name, test_field->name) != 0)
+ return false;
+ if (strcmp(field->type, test_field->type) != 0)
+ return false;
+ if (field->size != test_field->size)
+ return false;
+ if (field->is_signed != test_field->is_signed)
+ return false;
+
+ return true;
}
static bool hist_trigger_match(struct event_trigger_data *data,
- struct event_trigger_data *data_test)
+ struct event_trigger_data *data_test,
+ struct event_trigger_data *named_data,
+ bool ignore_filter)
{
struct tracing_map_sort_key *sort_key, *sort_key_test;
struct hist_trigger_data *hist_data, *hist_data_test;
struct hist_field *key_field, *key_field_test;
unsigned int i;
+ if (named_data && (named_data != data_test) &&
+ (named_data != data_test->named_data))
+ return false;
+
+ if (!named_data && is_named_trigger(data_test))
+ return false;
+
hist_data = data->private_data;
hist_data_test = data_test->private_data;
@@ -1249,9 +1335,11 @@ static bool hist_trigger_match(struct event_trigger_data *data,
hist_data->n_sort_keys != hist_data_test->n_sort_keys)
return false;
- if ((data->filter_str && !data_test->filter_str) ||
- (!data->filter_str && data_test->filter_str))
- return false;
+ if (!ignore_filter) {
+ if ((data->filter_str && !data_test->filter_str) ||
+ (!data->filter_str && data_test->filter_str))
+ return false;
+ }
for_each_hist_field(i, hist_data) {
key_field = hist_data->fields[i];
@@ -1259,7 +1347,7 @@ static bool hist_trigger_match(struct event_trigger_data *data,
if (key_field->flags != key_field_test->flags)
return false;
- if (key_field->field != key_field_test->field)
+ if (!compatible_field(key_field->field, key_field_test->field))
return false;
if (key_field->offset != key_field_test->offset)
return false;
@@ -1274,7 +1362,7 @@ static bool hist_trigger_match(struct event_trigger_data *data,
return false;
}
- if (data->filter_str &&
+ if (!ignore_filter && data->filter_str &&
(strcmp(data->filter_str, data_test->filter_str) != 0))
return false;
@@ -1286,12 +1374,26 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
struct trace_event_file *file)
{
struct hist_trigger_data *hist_data = data->private_data;
- struct event_trigger_data *test;
+ struct event_trigger_data *test, *named_data = NULL;
int ret = 0;
+ if (hist_data->attrs->name) {
+ named_data = find_named_trigger(hist_data->attrs->name);
+ if (named_data) {
+ if (!hist_trigger_match(data, named_data, named_data,
+ true)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+ }
+
+ if (hist_data->attrs->name && !named_data)
+ goto new;
+
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
- if (!hist_trigger_match(data, test))
+ if (!hist_trigger_match(data, test, named_data, false))
continue;
if (hist_data->attrs->pause)
test->paused = true;
@@ -1304,12 +1406,19 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
goto out;
}
}
-
+ new:
if (hist_data->attrs->cont || hist_data->attrs->clear) {
ret = -ENOENT;
goto out;
}
+ if (named_data) {
+ destroy_hist_data(data->private_data);
+ data->private_data = named_data->private_data;
+ set_named_trigger_data(data, named_data);
+ data->ops = &event_hist_trigger_named_ops;
+ }
+
if (hist_data->attrs->pause)
data->paused = true;
@@ -1323,6 +1432,7 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
ret++;
update_cond_flag(file);
+
if (trace_event_trigger_enable_disable(file, 1) < 0) {
list_del_rcu(&data->list);
update_cond_flag(file);
@@ -1336,12 +1446,16 @@ static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
{
- struct event_trigger_data *test;
+ struct hist_trigger_data *hist_data = data->private_data;
+ struct event_trigger_data *test, *named_data = NULL;
bool unregistered = false;
+ if (hist_data->attrs->name)
+ named_data = find_named_trigger(hist_data->attrs->name);
+
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
- if (!hist_trigger_match(data, test))
+ if (!hist_trigger_match(data, test, named_data, false))
continue;
unregistered = true;
list_del_rcu(&test->list);
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 20/23] kselftests/ftrace : Add event trigger testcases
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (18 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 19/23] tracing: Add support for named hist triggers Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 21/23] kselftests/ftrace: Add hist " Tom Zanussi
` (2 subsequent siblings)
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Ingo Molnar, Shuah Khan, Tom Zanussi
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
This adds simple event trigger testcases for ftracetest,
which covers following triggers.
- traceon-traceoff trigger
- enable/disable_event trigger
- snapshot trigger
- stacktrace trigger
- trigger filters
Here is the test result.
----
# ./ftracetest test.d/trigger/
=== Ftrace unit tests ===
[1] event trigger - test event enable/disable trigger [PASS]
[2] event trigger - test trigger filter [PASS]
[3] event trigger - test snapshot-trigger [PASS]
[4] event trigger - test stacktrace-trigger [PASS]
[5] event trigger - test traceon/off trigger [PASS]
# of passed: 5
# of failed: 0
# of unresolved: 0
# of untested: 0
# of unsupported: 0
# of xfailed: 0
# of undefined(test bug): 0
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
tools/testing/selftests/ftrace/test.d/functions | 9 +++
.../ftrace/test.d/trigger/trigger-eventonoff.tc | 64 ++++++++++++++++++++++
.../ftrace/test.d/trigger/trigger-filter.tc | 59 ++++++++++++++++++++
.../ftrace/test.d/trigger/trigger-snapshot.tc | 56 +++++++++++++++++++
.../ftrace/test.d/trigger/trigger-stacktrace.tc | 53 ++++++++++++++++++
.../ftrace/test.d/trigger/trigger-traceonoff.tc | 58 ++++++++++++++++++++
6 files changed, 299 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-eventonoff.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-filter.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-snapshot.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-stacktrace.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-traceonoff.tc
diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions
index 5d8cd06..c37262f 100644
--- a/tools/testing/selftests/ftrace/test.d/functions
+++ b/tools/testing/selftests/ftrace/test.d/functions
@@ -14,3 +14,12 @@ enable_tracing() { # start trace recording
reset_tracer() { # reset the current tracer
echo nop > current_tracer
}
+
+reset_trigger() { # reset all current setting triggers
+ grep -v ^# events/*/*/trigger |
+ while read line; do
+ cmd=`echo $line | cut -f2- -d: | cut -f1 -d" "`
+ echo "!$cmd" > `echo $line | cut -f1 -d:`
+ done
+}
+
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-eventonoff.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-eventonoff.tc
new file mode 100644
index 0000000..1a94450
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-eventonoff.tc
@@ -0,0 +1,64 @@
+#!/bin/sh
+# description: event trigger - test event enable/disable trigger
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+FEATURE=`grep enable_event events/sched/sched_process_fork/trigger`
+if [ -z "$FEATURE" ]; then
+ echo "event enable/disable trigger is not supported"
+ exit_unsupported
+fi
+
+echo "Test enable_event trigger"
+echo 0 > events/sched/sched_switch/enable
+echo 'enable_event:sched:sched_switch' > events/sched/sched_process_fork/trigger
+( echo "forked")
+if [ `cat events/sched/sched_switch/enable` != '1*' ]; then
+ fail "enable_event trigger on sched_process_fork did not work"
+fi
+
+reset_trigger
+
+echo "Test disable_event trigger"
+echo 1 > events/sched/sched_switch/enable
+echo 'disable_event:sched:sched_switch' > events/sched/sched_process_fork/trigger
+( echo "forked")
+if [ `cat events/sched/sched_switch/enable` != '0*' ]; then
+ fail "disable_event trigger on sched_process_fork did not work"
+fi
+
+reset_trigger
+
+echo "Test semantic error for event enable/disable trigger"
+! echo 'enable_event:nogroup:noevent' > events/sched/sched_process_fork/trigger
+! echo 'disable_event+1' > events/sched/sched_process_fork/trigger
+echo 'enable_event:sched:sched_switch' > events/sched/sched_process_fork/trigger
+! echo 'enable_event:sched:sched_switch' > events/sched/sched_process_fork/trigger
+! echo 'disable_event:sched:sched_switch' > events/sched/sched_process_fork/trigger
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-filter.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-filter.tc
new file mode 100644
index 0000000..514e466
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-filter.tc
@@ -0,0 +1,59 @@
+#!/bin/sh
+# description: event trigger - test trigger filter
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+echo "Test trigger filter"
+echo 1 > tracing_on
+echo 'traceoff if child_pid == 0' > events/sched/sched_process_fork/trigger
+( echo "forked")
+if [ `cat tracing_on` -ne 1 ]; then
+ fail "traceoff trigger on sched_process_fork did not work"
+fi
+
+reset_trigger
+
+echo "Test semantic error for trigger filter"
+! echo 'traceoff if a' > events/sched/sched_process_fork/trigger
+! echo 'traceoff if common_pid=0' > events/sched/sched_process_fork/trigger
+! echo 'traceoff if common_pid==b' > events/sched/sched_process_fork/trigger
+echo 'traceoff if common_pid == 0' > events/sched/sched_process_fork/trigger
+echo '!traceoff' > events/sched/sched_process_fork/trigger
+! echo 'traceoff if common_pid == child_pid' > events/sched/sched_process_fork/trigger
+echo 'traceoff if common_pid <= 0' > events/sched/sched_process_fork/trigger
+echo '!traceoff' > events/sched/sched_process_fork/trigger
+echo 'traceoff if common_pid >= 0' > events/sched/sched_process_fork/trigger
+echo '!traceoff' > events/sched/sched_process_fork/trigger
+echo 'traceoff if parent_pid >= 0 && child_pid >= 0' > events/sched/sched_process_fork/trigger
+echo '!traceoff' > events/sched/sched_process_fork/trigger
+echo 'traceoff if parent_pid >= 0 || child_pid >= 0' > events/sched/sched_process_fork/trigger
+echo '!traceoff' > events/sched/sched_process_fork/trigger
+
+
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-snapshot.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-snapshot.tc
new file mode 100644
index 0000000..f84b80d
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-snapshot.tc
@@ -0,0 +1,56 @@
+#!/bin/sh
+# description: event trigger - test snapshot-trigger
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+FEATURE=`grep snapshot events/sched/sched_process_fork/trigger`
+if [ -z "$FEATURE" ]; then
+ echo "snapshot trigger is not supported"
+ exit_unsupported
+fi
+
+echo "Test snapshot tigger"
+echo 0 > snapshot
+echo 1 > events/sched/sched_process_fork/enable
+( echo "forked")
+echo 'snapshot:1' > events/sched/sched_process_fork/trigger
+( echo "forked")
+grep sched_process_fork snapshot > /dev/null || \
+ fail "snapshot trigger on sched_process_fork did not work"
+
+reset_trigger
+echo 0 > snapshot
+echo 0 > events/sched/sched_process_fork/enable
+
+echo "Test snapshot semantic errors"
+
+! echo "snapshot+1" > events/sched/sched_process_fork/trigger
+echo "snapshot" > events/sched/sched_process_fork/trigger
+! echo "snapshot" > events/sched/sched_process_fork/trigger
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-stacktrace.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-stacktrace.tc
new file mode 100644
index 0000000..9fa23b0
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-stacktrace.tc
@@ -0,0 +1,53 @@
+#!/bin/sh
+# description: event trigger - test stacktrace-trigger
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+FEATURE=`grep stacktrace events/sched/sched_process_fork/trigger`
+if [ -z "$FEATURE" ]; then
+ echo "stacktrace trigger is not supported"
+ exit_unsupported
+fi
+
+echo "Test stacktrace tigger"
+echo 0 > trace
+echo 0 > options/stacktrace
+echo 'stacktrace' > events/sched/sched_process_fork/trigger
+( echo "forked")
+grep "<stack trace>" trace > /dev/null || \
+ fail "stacktrace trigger on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test stacktrace semantic errors"
+
+! echo "stacktrace:foo" > events/sched/sched_process_fork/trigger
+echo "stacktrace" > events/sched/sched_process_fork/trigger
+! echo "stacktrace" > events/sched/sched_process_fork/trigger
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-traceonoff.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-traceonoff.tc
new file mode 100644
index 0000000..87648e5
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-traceonoff.tc
@@ -0,0 +1,58 @@
+#!/bin/sh
+# description: event trigger - test traceon/off trigger
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+echo "Test traceoff trigger"
+echo 1 > tracing_on
+echo 'traceoff' > events/sched/sched_process_fork/trigger
+( echo "forked")
+if [ `cat tracing_on` -ne 0 ]; then
+ fail "traceoff trigger on sched_process_fork did not work"
+fi
+
+reset_trigger
+
+echo "Test traceon trigger"
+echo 0 > tracing_on
+echo 'traceon' > events/sched/sched_process_fork/trigger
+( echo "forked")
+if [ `cat tracing_on` -ne 1 ]; then
+ fail "traceoff trigger on sched_process_fork did not work"
+fi
+
+reset_trigger
+
+echo "Test semantic error for traceoff/on trigger"
+! echo 'traceoff:badparam' > events/sched/sched_process_fork/trigger
+! echo 'traceoff+0' > events/sched/sched_process_fork/trigger
+echo 'traceon' > events/sched/sched_process_fork/trigger
+! echo 'traceon' > events/sched/sched_process_fork/trigger
+! echo 'traceoff' > events/sched/sched_process_fork/trigger
+
+do_reset
+
+exit 0
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 21/23] kselftests/ftrace: Add hist trigger testcases
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (19 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 20/23] kselftests/ftrace : Add event trigger testcases Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 22/23] tracing: Add hist trigger 'log2' modifier Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 23/23] kselftests/ftrace: Add a test for log2 modifier of hist trigger Tom Zanussi
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Ingo Molnar, Shuah Khan, Tom Zanussi
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Add the hist trigger testcases for ftracetest.
This checks the basic histogram trigger behaviors like as;
- Histogram trigger itself
- Histogram with string key
- Histogram with compound keys
- Histogram with sort key
- Histogram trigger modifiers (execname, hex, syscall)
- Multiple histograms on an event
- Named histogram
- Named histogram on multi events
Here is the test result.
----
# ./ftracetest test.d/trigger/*hist*.tc
=== Ftrace unit tests ===
[1] event trigger - test histogram modifiers [PASS]
[2] event trigger - test histogram trigger [PASS]
[3] event trigger - test multiple histogram triggers [PASS]
# of passed: 3
# of failed: 0
# of unresolved: 0
# of untested: 0
# of unsupported: 0
# of xfailed: 0
# of undefined(test bug): 0
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[Tom Zanussi: Change multihist test from truncate ('>') to append ('>>')]
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
---
.../ftrace/test.d/trigger/trigger-hist-mod.tc | 65 +++++++++++++++++
.../ftrace/test.d/trigger/trigger-hist.tc | 83 ++++++++++++++++++++++
.../ftrace/test.d/trigger/trigger-multihist.tc | 73 +++++++++++++++++++
3 files changed, 221 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-hist.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
new file mode 100644
index 0000000..57e350a
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
@@ -0,0 +1,65 @@
+#!/bin/sh
+# description: event trigger - test histogram modifiers
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+FEATURE=`grep hist events/sched/sched_process_fork/trigger`
+if [ -z "$FEATURE" ]; then
+ echo "hist trigger is not supported"
+ exit_unsupported
+fi
+
+echo "Test histogram with execname modifier"
+
+echo 'hist:keys=common_pid.execname' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+COMM=`cat /proc/$$/comm`
+grep "common_pid: $COMM" events/sched/sched_process_fork/hist > /dev/null || \
+ fail "execname modifier on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test histogram with hex modifier"
+
+echo 'hist:keys=parent_pid.hex' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+# Note that $$ is the parent pid. $PID is current PID.
+HEX=`printf %x $PID`
+grep "parent_pid: $HEX" events/sched/sched_process_fork/hist > /dev/null || \
+ fail "hex modifier on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test histogram with syscall modifier"
+
+echo 'hist:keys=id.syscall' > events/raw_syscalls/sys_exit/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep "id: sys_" events/raw_syscalls/sys_exit/hist > /dev/null || \
+ fail "syscall modifier on raw_syscalls/sys_exit did not work"
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist.tc
new file mode 100644
index 0000000..b2902d4
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist.tc
@@ -0,0 +1,83 @@
+#!/bin/sh
+# description: event trigger - test histogram trigger
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+FEATURE=`grep hist events/sched/sched_process_fork/trigger`
+if [ -z "$FEATURE" ]; then
+ echo "hist trigger is not supported"
+ exit_unsupported
+fi
+
+echo "Test histogram basic tigger"
+
+echo 'hist:keys=parent_pid:vals=child_pid' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep parent_pid events/sched/sched_process_fork/hist > /dev/null || \
+ fail "hist trigger on sched_process_fork did not work"
+grep child events/sched/sched_process_fork/hist > /dev/null || \
+ fail "hist trigger on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test histogram with compound keys"
+
+echo 'hist:keys=parent_pid,child_pid' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep '^{ parent_pid:.*, child_pid:.*}' events/sched/sched_process_fork/hist > /dev/null || \
+ fail "compound keys on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test histogram with string key"
+
+echo 'hist:keys=parent_comm' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+COMM=`cat /proc/$$/comm`
+grep "parent_comm: $COMM" events/sched/sched_process_fork/hist > /dev/null || \
+ fail "string key on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test histogram with sort key"
+
+echo 'hist:keys=parent_pid,child_pid:sort=child_pid.ascending' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+
+check_inc() {
+ while [ $# -gt 1 ]; do
+ [ $1 -gt $2 ] && return 1
+ shift 1
+ done
+ return 0
+}
+check_inc `grep -o "child_pid:[[:space:]]*[[:digit:]]*" \
+ events/sched/sched_process_fork/hist | cut -d: -f2 ` ||
+ fail "sort param on sched_process_fork did not work"
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc
new file mode 100644
index 0000000..03c4a46
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-multihist.tc
@@ -0,0 +1,73 @@
+#!/bin/sh
+# description: event trigger - test multiple histogram triggers
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit $FAIL
+}
+
+if [ ! -f set_event -o ! -d events/sched ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/sched/sched_process_fork/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+reset_tracer
+do_reset
+
+FEATURE=`grep hist events/sched/sched_process_fork/trigger`
+if [ -z "$FEATURE" ]; then
+ echo "hist trigger is not supported"
+ exit_unsupported
+fi
+
+reset_trigger
+
+echo "Test histogram multiple tiggers"
+
+echo 'hist:keys=parent_pid:vals=child_pid' > events/sched/sched_process_fork/trigger
+echo 'hist:keys=parent_comm:vals=child_pid' >> events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep parent_pid events/sched/sched_process_fork/hist > /dev/null || \
+ fail "hist trigger on sched_process_fork did not work"
+grep child events/sched/sched_process_fork/hist > /dev/null || \
+ fail "hist trigger on sched_process_fork did not work"
+COMM=`cat /proc/$$/comm`
+grep "parent_comm: $COMM" events/sched/sched_process_fork/hist > /dev/null || \
+ fail "string key on sched_process_fork did not work"
+
+reset_trigger
+
+echo "Test histogram with its name"
+
+echo 'hist:name=test_hist:keys=common_pid' > events/sched/sched_process_fork/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep test_hist events/sched/sched_process_fork/hist > /dev/null || \
+ fail "named event on sched_process_fork did not work"
+
+echo "Test same named histogram on different events"
+
+echo 'hist:name=test_hist:keys=common_pid' > events/sched/sched_process_exit/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep test_hist events/sched/sched_process_exit/hist > /dev/null || \
+ fail "named event on sched_process_fork did not work"
+
+diffs=`diff events/sched/sched_process_exit/hist events/sched/sched_process_fork/hist | wc -l`
+test $diffs -eq 0 || fail "Same name histograms are not same"
+
+reset_trigger
+
+do_reset
+
+exit 0
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 22/23] tracing: Add hist trigger 'log2' modifier
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (20 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 21/23] kselftests/ftrace: Add hist " Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 23/23] kselftests/ftrace: Add a test for log2 modifier of hist trigger Tom Zanussi
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Tom Zanussi
From: Namhyung Kim <namhyung@kernel.org>
Allow users to have numeric fields displayed as log2 values in case
value range is very wide by appending '.log2' to field names.
For example,
# echo 'hist:key=bytes_req' > kmalloc/trigger
# cat kmalloc/hist
{ bytes_req: 504 } hitcount: 1
{ bytes_req: 11 } hitcount: 1
{ bytes_req: 104 } hitcount: 1
{ bytes_req: 48 } hitcount: 1
{ bytes_req: 2048 } hitcount: 1
{ bytes_req: 4096 } hitcount: 1
{ bytes_req: 240 } hitcount: 1
{ bytes_req: 392 } hitcount: 1
{ bytes_req: 13 } hitcount: 1
{ bytes_req: 28 } hitcount: 1
{ bytes_req: 12 } hitcount: 1
{ bytes_req: 64 } hitcount: 2
{ bytes_req: 128 } hitcount: 2
{ bytes_req: 32 } hitcount: 2
{ bytes_req: 8 } hitcount: 11
{ bytes_req: 10 } hitcount: 13
{ bytes_req: 24 } hitcount: 25
{ bytes_req: 160 } hitcount: 29
{ bytes_req: 16 } hitcount: 33
{ bytes_req: 80 } hitcount: 36
When using '.log2' modifier, the output looks like:
# echo 'hist:key=bytes_req.log2' > kmalloc/trigger
# cat kmalloc/hist
{ bytes_req: ~ 2^12 } hitcount: 1
{ bytes_req: ~ 2^11 } hitcount: 1
{ bytes_req: ~ 2^9 } hitcount: 2
{ bytes_req: ~ 2^6 } hitcount: 3
{ bytes_req: ~ 2^3 } hitcount: 13
{ bytes_req: ~ 2^5 } hitcount: 19
{ bytes_req: ~ 2^8 } hitcount: 49
{ bytes_req: ~ 2^7 } hitcount: 57
{ bytes_req: ~ 2^4 } hitcount: 74
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
kernel/trace/trace.c | 1 +
kernel/trace/trace_events_hist.c | 20 ++++++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index ce8b885..7abfd25 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3863,6 +3863,7 @@ static const char readme_msg[] =
"\t .sym-offset display an address as a symbol and offset\n"
"\t .execname display a common_pid as a program name\n"
"\t .syscall display a syscall id as a syscall name\n\n"
+ "\t .log2 display log2 value rather than raw number\n\n"
"\t The 'pause' parameter can be used to pause an existing hist\n"
"\t trigger or to start a hist trigger but not log any events\n"
"\t until told to do so. 'continue' can be used to start or\n"
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 7c65652..e102267 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -68,6 +68,13 @@ static u64 hist_field_pstring(struct hist_field *hist_field, void *event)
return (u64)(unsigned long)*addr;
}
+static u64 hist_field_log2(struct hist_field *hist_field, void *event)
+{
+ u64 val = *(u64 *)(event + hist_field->field->offset);
+
+ return (u64) ilog2(roundup_pow_of_two(val));
+}
+
#define DEFINE_HIST_FIELD_FN(type) \
static u64 hist_field_##type(struct hist_field *hist_field, void *event)\
{ \
@@ -111,6 +118,7 @@ enum hist_field_flags {
HIST_FIELD_FL_EXECNAME = 64,
HIST_FIELD_FL_SYSCALL = 128,
HIST_FIELD_FL_STACKTRACE = 256,
+ HIST_FIELD_FL_LOG2 = 512,
};
struct hist_trigger_attrs {
@@ -358,6 +366,11 @@ static struct hist_field *create_hist_field(struct ftrace_event_field *field,
goto out;
}
+ if (flags & HIST_FIELD_FL_LOG2) {
+ hist_field->fn = hist_field_log2;
+ goto out;
+ }
+
if (is_string_field(field)) {
flags |= HIST_FIELD_FL_STRING;
@@ -518,6 +531,8 @@ static int create_key_field(struct hist_trigger_data *hist_data,
flags |= HIST_FIELD_FL_EXECNAME;
else if (strcmp(field_str, "syscall") == 0)
flags |= HIST_FIELD_FL_SYSCALL;
+ else if (strcmp(field_str, "log2") == 0)
+ flags |= HIST_FIELD_FL_LOG2;
else {
ret = -EINVAL;
goto out;
@@ -974,6 +989,9 @@ hist_trigger_entry_print(struct seq_file *m,
key + key_field->offset,
HIST_STACKTRACE_DEPTH);
multiline = true;
+ } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
+ seq_printf(m, "%s: ~ 2^%-2llu", key_field->field->name,
+ *(u64 *)(key + key_field->offset));
} else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
@@ -1106,6 +1124,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field)
flags_str = "execname";
else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
flags_str = "syscall";
+ else if (hist_field->flags & HIST_FIELD_FL_LOG2)
+ flags_str = "log2";
return flags_str;
}
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* [PATCH v15 23/23] kselftests/ftrace: Add a test for log2 modifier of hist trigger
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
` (21 preceding siblings ...)
2016-02-26 16:01 ` [PATCH v15 22/23] tracing: Add hist trigger 'log2' modifier Tom Zanussi
@ 2016-02-26 16:01 ` Tom Zanussi
22 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-02-26 16:01 UTC (permalink / raw)
To: rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel, Ingo Molnar, Shuah Khan, Tom Zanussi
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Add a test for log2 modifier of hist trigger in hist_mod.tc.
Here is the test result.
----
# ./ftracetest test.d/trigger/trigger-hist-mod.tc
=== Ftrace unit tests ===
[1] event trigger - test histogram modifiers [PASS]
# of passed: 1
# of failed: 0
# of unresolved: 0
# of untested: 0
# of unsupported: 0
# of xfailed: 0
# of undefined(test bug): 0
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
.../selftests/ftrace/test.d/trigger/trigger-hist-mod.tc | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
index 57e350a..c2b61c4 100644
--- a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-mod.tc
@@ -60,6 +60,16 @@ for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
grep "id: sys_" events/raw_syscalls/sys_exit/hist > /dev/null || \
fail "syscall modifier on raw_syscalls/sys_exit did not work"
+
+reset_trigger
+
+echo "Test histgram with log2 modifier"
+
+echo 'hist:keys=bytes_req.log2' > events/kmem/kmalloc/trigger
+for i in `seq 1 10` ; do ( echo "forked" > /dev/null); done
+grep 'bytes_req: ~ 2^[0-9]*' events/kmem/kmalloc/hist > /dev/null || \
+ fail "log2 modifier on kmem/kmalloc did not work"
+
do_reset
exit 0
--
1.9.3
^ permalink raw reply related [flat|nested] 28+ messages in thread
* Re: [PATCH v15 02/23] tracing: Add 'hist' event trigger command
2016-02-26 16:01 ` [PATCH v15 02/23] tracing: Add 'hist' event trigger command Tom Zanussi
@ 2016-03-02 14:33 ` Steven Rostedt
0 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2016-03-02 14:33 UTC (permalink / raw)
To: Tom Zanussi
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel
On Fri, 26 Feb 2016 10:01:05 -0600
Tom Zanussi <tom.zanussi@linux.intel.com> wrote:
> +static int create_hitcount_val(struct hist_trigger_data *hist_data)
> +{
> + hist_data->fields[HITCOUNT_IDX] =
> + create_hist_field(NULL, HIST_FIELD_FL_HITCOUNT);
> + if (!hist_data->fields[HITCOUNT_IDX])
> + return -ENOMEM;
> +
> + if (WARN_ON(++hist_data->n_vals > TRACING_MAP_VALS_MAX))
Never put side effects in a WARN_ON() macro. Some configs define
WARN_ON() as a nop. Which would break this code. Always do the
following:
hist_data->n_vals++;
if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int create_val_fields(struct hist_trigger_data *hist_data,
> + struct trace_event_file *file)
> +{
> + int ret;
> +
> + ret = create_hitcount_val(hist_data);
> +
> + return ret;
> +}
> +
> +static int create_key_field(struct hist_trigger_data *hist_data,
> + unsigned int key_idx,
> + struct trace_event_file *file,
> + char *field_str)
> +{
> + struct ftrace_event_field *field = NULL;
> + unsigned long flags = 0;
> + unsigned int key_size;
> + int ret = 0;
> +
> + if (WARN_ON(key_idx >= TRACING_MAP_FIELDS_MAX))
> + return -EINVAL;
> +
> + flags |= HIST_FIELD_FL_KEY;
> +
> + field = trace_find_event_field(file->event_call, field_str);
> + if (!field) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + key_size = field->size;
> +
> + hist_data->fields[key_idx] = create_hist_field(field, flags);
> + if (!hist_data->fields[key_idx]) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + key_size = ALIGN(key_size, sizeof(u64));
> + hist_data->fields[key_idx]->size = key_size;
> + hist_data->key_size = key_size;
> + if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + if (WARN_ON(++hist_data->n_keys > TRACING_MAP_KEYS_MAX))
Same here.
> + return -EINVAL;
> +
> + ret = key_size;
> + out:
> + return ret;
> +}
> +
-- Steve
^ permalink raw reply [flat|nested] 28+ messages in thread
* Re: [PATCH v15 03/23] tracing: Add hist trigger support for multiple values ('vals=' param)
2016-02-26 16:01 ` [PATCH v15 03/23] tracing: Add hist trigger support for multiple values ('vals=' param) Tom Zanussi
@ 2016-03-02 14:38 ` Steven Rostedt
0 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2016-03-02 14:38 UTC (permalink / raw)
To: Tom Zanussi
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel
On Fri, 26 Feb 2016 10:01:06 -0600
Tom Zanussi <tom.zanussi@linux.intel.com> wrote:
> +static int create_val_field(struct hist_trigger_data *hist_data,
> + unsigned int val_idx,
> + struct trace_event_file *file,
> + char *field_str)
> +{
> + struct ftrace_event_field *field = NULL;
> + unsigned long flags = 0;
> + int ret = 0;
> +
> + if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
> + return -EINVAL;
> + field = trace_find_event_field(file->event_call, field_str);
> + if (!field) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + hist_data->fields[val_idx] = create_hist_field(field, flags);
> + if (!hist_data->fields[val_idx]) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + if (WARN_ON(++hist_data->n_vals > TRACING_MAP_VALS_MAX))
> + ret = -EINVAL;
Again, move the increment out of the WARN_ON().
> + out:
> + return ret;
> +}
> +
-- Steve
^ permalink raw reply [flat|nested] 28+ messages in thread
* Re: [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier
2016-02-26 16:01 ` [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier Tom Zanussi
@ 2016-03-02 17:39 ` Steven Rostedt
2016-03-02 19:51 ` Tom Zanussi
0 siblings, 1 reply; 28+ messages in thread
From: Steven Rostedt @ 2016-03-02 17:39 UTC (permalink / raw)
To: Tom Zanussi
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel
On Fri, 26 Feb 2016 10:01:13 -0600
Tom Zanussi <tom.zanussi@linux.intel.com> wrote:
> +static void hist_trigger_elt_copy(struct tracing_map_elt *to,
> + struct tracing_map_elt *from)
> +{
> + char *comm_from = from->private_data;
> + char *comm_to = to->private_data;
> +
> + if (comm_from)
> + memcpy(comm_to, comm_from, TASK_COMM_LEN + 1);
> +}
> +
> +static void hist_trigger_elt_init(struct tracing_map_elt *elt)
> +{
> + char *comm = elt->private_data;
> +
> + if (comm)
> + save_comm(comm, current);
> +}
> +
> +static const struct tracing_map_ops hist_trigger_ops = {
> + .elt_alloc = hist_trigger_elt_alloc,
> + .elt_copy = hist_trigger_elt_copy,
> + .elt_free = hist_trigger_elt_free,
> + .elt_init = hist_trigger_elt_init,
These are only used for saving or displaying comm. Wouldn't adding that
in the name be better. Otherwise it looks like they are more generic. I
find that dangerous, especially since they just assume that the
private_data is a string.
What about hist_trigger_elt_comm_*
?
-- Steve
> +};
> +
> static void destroy_hist_field(struct hist_field *hist_field)
> {
> kfree(hist_field);
> @@ -399,6 +467,9 @@ static int create_key_field(struct hist_trigger_data *hist_data,
> flags |= HIST_FIELD_FL_SYM;
> else if (strcmp(field_str, "sym-offset") == 0)
> flags |= HIST_FIELD_FL_SYM_OFFSET;
> + else if ((strcmp(field_str, "execname") == 0) &&
> + (strcmp(field_name, "common_pid") == 0))
> + flags |= HIST_FIELD_FL_EXECNAME;
> else {
> ret = -EINVAL;
> goto out;
^ permalink raw reply [flat|nested] 28+ messages in thread
* Re: [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier
2016-03-02 17:39 ` Steven Rostedt
@ 2016-03-02 19:51 ` Tom Zanussi
0 siblings, 0 replies; 28+ messages in thread
From: Tom Zanussi @ 2016-03-02 19:51 UTC (permalink / raw)
To: Steven Rostedt
Cc: masami.hiramatsu.pt, namhyung, josh, andi, mathieu.desnoyers,
peterz, linux-kernel
Hi Steve,
On Wed, 2016-03-02 at 12:39 -0500, Steven Rostedt wrote:
> On Fri, 26 Feb 2016 10:01:13 -0600
> Tom Zanussi <tom.zanussi@linux.intel.com> wrote:
>
>
> > +static void hist_trigger_elt_copy(struct tracing_map_elt *to,
> > + struct tracing_map_elt *from)
> > +{
> > + char *comm_from = from->private_data;
> > + char *comm_to = to->private_data;
> > +
> > + if (comm_from)
> > + memcpy(comm_to, comm_from, TASK_COMM_LEN + 1);
> > +}
> > +
> > +static void hist_trigger_elt_init(struct tracing_map_elt *elt)
> > +{
> > + char *comm = elt->private_data;
> > +
> > + if (comm)
> > + save_comm(comm, current);
> > +}
> > +
> > +static const struct tracing_map_ops hist_trigger_ops = {
> > + .elt_alloc = hist_trigger_elt_alloc,
> > + .elt_copy = hist_trigger_elt_copy,
> > + .elt_free = hist_trigger_elt_free,
> > + .elt_init = hist_trigger_elt_init,
>
> These are only used for saving or displaying comm. Wouldn't adding that
> in the name be better. Otherwise it looks like they are more generic. I
> find that dangerous, especially since they just assume that the
> private_data is a string.
>
> What about hist_trigger_elt_comm_*
>
> ?
Yeah, I think that makes it clearer - I'll rename those to be more
explicit.
Thanks,
Tom
>
> -- Steve
>
> > +};
> > +
> > static void destroy_hist_field(struct hist_field *hist_field)
> > {
> > kfree(hist_field);
> > @@ -399,6 +467,9 @@ static int create_key_field(struct hist_trigger_data *hist_data,
> > flags |= HIST_FIELD_FL_SYM;
> > else if (strcmp(field_str, "sym-offset") == 0)
> > flags |= HIST_FIELD_FL_SYM_OFFSET;
> > + else if ((strcmp(field_str, "execname") == 0) &&
> > + (strcmp(field_name, "common_pid") == 0))
> > + flags |= HIST_FIELD_FL_EXECNAME;
> > else {
> > ret = -EINVAL;
> > goto out;
^ permalink raw reply [flat|nested] 28+ messages in thread
end of thread, other threads:[~2016-03-02 19:52 UTC | newest]
Thread overview: 28+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-02-26 16:01 [PATCH 00/23] tracing: 'hist' triggers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 01/23] tracing: Update some tracing_map constants and comments Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 02/23] tracing: Add 'hist' event trigger command Tom Zanussi
2016-03-02 14:33 ` Steven Rostedt
2016-02-26 16:01 ` [PATCH v15 03/23] tracing: Add hist trigger support for multiple values ('vals=' param) Tom Zanussi
2016-03-02 14:38 ` Steven Rostedt
2016-02-26 16:01 ` [PATCH v15 04/23] tracing: Add hist trigger support for compound keys Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 05/23] tracing: Add hist trigger support for user-defined sorting ('sort=' param) Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 06/23] tracing: Add hist trigger support for pausing and continuing a trace Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 07/23] tracing: Add hist trigger support for clearing " Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 08/23] tracing: Add hist trigger 'hex' modifier for displaying numeric fields Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 09/23] tracing: Add hist trigger 'sym' and 'sym-offset' modifiers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 10/23] tracing: Add hist trigger 'execname' modifier Tom Zanussi
2016-03-02 17:39 ` Steven Rostedt
2016-03-02 19:51 ` Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 11/23] tracing: Add hist trigger 'syscall' modifier Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 12/23] tracing: Add hist trigger support for stacktraces as keys Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 13/23] tracing: Support string type key properly Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 14/23] tracing: Remove restriction on string position in hist trigger keys Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 15/23] tracing: Add enable_hist/disable_hist triggers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 16/23] tracing: Add 'hist' trigger Documentation Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 17/23] tracing: Add support for multiple hist triggers per event Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 18/23] tracing: Add support for named triggers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 19/23] tracing: Add support for named hist triggers Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 20/23] kselftests/ftrace : Add event trigger testcases Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 21/23] kselftests/ftrace: Add hist " Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 22/23] tracing: Add hist trigger 'log2' modifier Tom Zanussi
2016-02-26 16:01 ` [PATCH v15 23/23] kselftests/ftrace: Add a test for log2 modifier of hist trigger Tom Zanussi
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