diff options
| author | Adrian Hunter | 2020-07-10 18:10:54 +0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo | 2020-08-06 08:18:32 -0300 |
| commit | a58a057ce65b52125dd355b7d8b0d540ea267a5f (patch) | |
| tree | 62af8dc052610f8072ef15e8e53d0cf22c0793c5 /tools | |
| parent | 401136bb084fd021acd9f8c51b52fe0a25e326b2 (diff) | |
perf intel-pt: Fix duplicate branch after CBR
CBR events can result in a duplicate branch event, because the state
type defaults to a branch. Fix by clearing the state type.
Example: trace 'sleep' and hope for a frequency change
Before:
$ perf record -e intel_pt//u sleep 0.1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.034 MB perf.data ]
$ perf script --itrace=bpe > before.txt
After:
$ perf script --itrace=bpe > after.txt
$ diff -u before.txt after.txt
--- before.txt 2020-07-07 14:42:18.191508098 +0300
+++ after.txt 2020-07-07 14:42:36.587891753 +0300
@@ -29673,7 +29673,6 @@
sleep 93431 [007] 15411.619905: 1 branches:u: 0 [unknown] ([unknown]) => 7f0818abb2e0 clock_nanosleep@@GLIBC_2.17+0x0 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
sleep 93431 [007] 15411.619905: 1 branches:u: 7f0818abb30c clock_nanosleep@@GLIBC_2.17+0x2c (/usr/lib/x86_64-linux-gnu/libc-2.31.so) => 0 [unknown] ([unknown])
sleep 93431 [007] 15411.720069: cbr: cbr: 15 freq: 1507 MHz ( 56%) 7f0818abb30c clock_nanosleep@@GLIBC_2.17+0x2c (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
- sleep 93431 [007] 15411.720069: 1 branches:u: 7f0818abb30c clock_nanosleep@@GLIBC_2.17+0x2c (/usr/lib/x86_64-linux-gnu/libc-2.31.so) => 0 [unknown] ([unknown])
sleep 93431 [007] 15411.720076: 1 branches:u: 0 [unknown] ([unknown]) => 7f0818abb30e clock_nanosleep@@GLIBC_2.17+0x2e (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
sleep 93431 [007] 15411.720077: 1 branches:u: 7f0818abb323 clock_nanosleep@@GLIBC_2.17+0x43 (/usr/lib/x86_64-linux-gnu/libc-2.31.so) => 7f0818ac0eb7 __nanosleep+0x17 (/usr/lib/x86_64-linux-gnu/libc-2.31.so)
sleep 93431 [007] 15411.720077: 1 branches:u: 7f0818ac0ebf __nanosleep+0x1f (/usr/lib/x86_64-linux-gnu/libc-2.31.so) => 55cb7e4c2827 rpl_nanosleep+0x97 (/usr/bin/sleep)
Fixes: 91de8684f1cff ("perf intel-pt: Cater for CBR change in PSB+")
Fixes: abe5a1d3e4bee ("perf intel-pt: Decoder to output CBR changes immediately")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200710151104.15137-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c index 75c4bd74d521..7ffcbd6fcd1a 100644 --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1977,8 +1977,10 @@ next: * possibility of another CBR change that gets caught up * in the PSB+. */ - if (decoder->cbr != decoder->cbr_seen) + if (decoder->cbr != decoder->cbr_seen) { + decoder->state.type = 0; return 0; + } break; case INTEL_PT_PIP: @@ -2019,8 +2021,10 @@ next: case INTEL_PT_CBR: intel_pt_calc_cbr(decoder); - if (decoder->cbr != decoder->cbr_seen) + if (decoder->cbr != decoder->cbr_seen) { + decoder->state.type = 0; return 0; + } break; case INTEL_PT_MODE_EXEC: |