diff options
| author | Andi Kleen <ak@linux.intel.com> | 2016-03-28 10:45:38 -0700 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-03-30 11:14:09 -0300 |
| commit | d1706b39f0af6901ab2a5e2ebb210b53c1a5bdc7 (patch) | |
| tree | 4bee0f637581706387688651a57fb867c7f6e559 /tools/perf/util/auxtrace.h | |
| parent | f7380c12ec6cfd69f274ba6181cd01c764f877bb (diff) | |
perf tools: Add support for skipping itrace instructions
When using 'perf script' to look at PT traces it is often useful to
ignore the initialization code at the beginning.
On larger traces which may have many millions of instructions in
initialization code doing that in a pipeline can be very slow, with perf
script spending a lot of CPU time calling printf and writing data.
This patch adds an extension to the --itrace argument that skips 'n'
events (instructions, branches or transactions) at the beginning. This
is much more efficient.
v2:
Add support for BTS (Adrian Hunter)
Document in itrace.txt
Fix branch check
Check transactions and instructions too
Committer note:
To test intel_pt one needs to make sure VT-x isn't active, i.e.
stopping KVM guests on the test machine, as described by Andi Kleen
at http://lkml.kernel.org/r/20160301234953.GD23621@tassilo.jf.intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1459187142-20035-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/auxtrace.h')
| -rw-r--r-- | tools/perf/util/auxtrace.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h index 57ff31ecb8e4..767989e0e312 100644 --- a/tools/perf/util/auxtrace.h +++ b/tools/perf/util/auxtrace.h @@ -68,6 +68,7 @@ enum itrace_period_type { * @last_branch_sz: branch context size * @period: 'instructions' events period * @period_type: 'instructions' events period type + * @initial_skip: skip N events at the beginning. */ struct itrace_synth_opts { bool set; @@ -86,6 +87,7 @@ struct itrace_synth_opts { unsigned int last_branch_sz; unsigned long long period; enum itrace_period_type period_type; + unsigned long initial_skip; }; /** |