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a58a057ce6
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>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.