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| author | Steven Rostedt <rostedt@goodmis.org> | 2008-11-12 05:14:40 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-11-12 10:52:02 (GMT) |
| commit | 52f232cb720a7babb752849cbc2cab2d24021209 (patch) | |
| tree | 47c7e800549457bd5ab9b54f47729acac6e10780 /kernel/trace/Makefile | |
| parent | 1f0d69a9fc815db82f15722bf05227190b1d714d (diff) | |
| download | linux-52f232cb720a7babb752849cbc2cab2d24021209.tar.xz | |
tracing: likely/unlikely branch annotation tracer
Impact: new likely/unlikely branch tracer
This patch adds a way to record the instances of the likely() and unlikely()
branch condition annotations.
When "unlikely" is set in /debugfs/tracing/iter_ctrl the unlikely conditions
will be added to any of the ftrace tracers. The change takes effect when
a new tracer is passed into the current_tracer file.
For example:
bash-3471 [003] 357.014755: [INCORRECT] sched_info_dequeued:sched_stats.h:177
bash-3471 [003] 357.014756: [correct] update_curr:sched_fair.c:489
bash-3471 [003] 357.014758: [correct] calc_delta_fair:sched_fair.c:411
bash-3471 [003] 357.014759: [correct] account_group_exec_runtime:sched_stats.h:356
bash-3471 [003] 357.014761: [correct] update_curr:sched_fair.c:489
bash-3471 [003] 357.014763: [INCORRECT] calc_delta_fair:sched_fair.c:411
bash-3471 [003] 357.014765: [correct] calc_delta_mine:sched.c:1279
Which shows the normal tracer heading, as well as whether the condition was
correct "[correct]" or was mistaken "[INCORRECT]", followed by the function,
file name and line number.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace/Makefile')
| -rw-r--r-- | kernel/trace/Makefile | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 98e70ee..c938d03 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -10,6 +10,12 @@ CFLAGS_trace_selftest_dynamic.o = -pg obj-y += trace_selftest_dynamic.o endif +# If unlikely tracing is enabled, do not trace these files +ifdef CONFIG_TRACING_UNLIKELY +KBUILD_CFLAGS += '-Dlikely(x)=likely_notrace(x)' +KBUILD_CFLAGS += '-Dunlikely(x)=unlikely_notrace(x)' +endif + obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o obj-$(CONFIG_RING_BUFFER) += ring_buffer.o |