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alistair23-linux/tools/perf/util/intel-pt-decoder
Adrian Hunter 55052ac61c perf intel-pt: Fix duplicate branch after CBR
commit a58a057ce6 upstream.

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: 91de8684f1 ("perf intel-pt: Cater for CBR change in PSB+")
Fixes: abe5a1d3e4 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:29 +02:00
..
Build perf intel-pt: Use shared x86 insn decoder 2019-08-31 22:27:52 -03:00
intel-pt-decoder.c perf intel-pt: Fix duplicate branch after CBR 2020-08-21 13:05:29 +02:00
intel-pt-decoder.h perf intel-pt: Add CBR value to decoder state 2019-06-25 08:47:10 -03:00
intel-pt-insn-decoder.c perf intel-pt: Use shared x86 insn decoder 2019-08-31 22:27:52 -03:00
intel-pt-insn-decoder.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
intel-pt-log.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
intel-pt-log.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
intel-pt-pkt-decoder.c perf intel-pt: Add new packets for PEBS via PT 2019-06-17 15:57:17 -03:00
intel-pt-pkt-decoder.h perf intel-pt: Add new packets for PEBS via PT 2019-06-17 15:57:17 -03:00