<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel.git/tools/perf/util/evsel.h, branch linux-6.3.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.
</subtitle>
<id>https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.3.y</id>
<link rel='self' href='https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.3.y'/>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/'/>
<updated>2023-07-11T17:39:45Z</updated>
<entry>
<title>perf evsel: Don't let for_each_group() treat the head of the list as one of its nodes</title>
<updated>2023-07-11T17:39:45Z</updated>
<author>
<name>Ian Rogers</name>
</author>
<published>2023-05-26T19:44:42Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=56f074d6bce22cd1bad739673ff6d44cddfabc25'/>
<id>urn:sha1:56f074d6bce22cd1bad739673ff6d44cddfabc25</id>
<content type='text'>
[ Upstream commit 797b9ec8c4bc9ec89f633a9b2c710b7b64753ca4 ]

Address/memory sanitizer was reporting issues in evsel__group_pmu_name
because the for_each_group_evsel loop didn't terminate when the head
was reached, the head would then be cast and accessed as an evsel
leading to invalid memory accesses.

Fix for_each_group_member and for_each_group_evsel to terminate at the
list head. Note, evsel__group_pmu_name no longer iterates the group, but
the problem is present regardless.

Fixes: 717e263fc354d53d ("perf report: Show group description when event group is enabled")
Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Changbin Du &lt;changbin.du@huawei.com&gt;
Cc: Dmitrii Dolgov &lt;9erthalion6@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@arm.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rob Herring &lt;robh@kernel.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Xing Zhengjun &lt;zhengjun.xing@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20230526194442.2355872-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>perf stat: Separate bperf from bpf_profiler</title>
<updated>2023-05-17T12:01:51Z</updated>
<author>
<name>Dmitrii Dolgov</name>
</author>
<published>2023-04-12T18:23:16Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=bc7eae6d98e9009cb34124d758637c1312fd5777'/>
<id>urn:sha1:bc7eae6d98e9009cb34124d758637c1312fd5777</id>
<content type='text'>
[ Upstream commit ecc68ee216c6c5b2f84915e1441adf436f1b019b ]

It seems that perf stat -b &lt;prog id&gt; doesn't produce any results:

    $ perf stat -e cycles -b 4 -I 10000 -vvv
    Control descriptor is not initialized
    cycles: 0 0 0
                time        counts unit      events
	10.007641640    &lt;not supported&gt;      cycles

Looks like this happens because fentry/fexit progs are getting loaded, but the
corresponding perf event is not enabled and not added into the events bpf map.
I think there is some mixing up between two type of bpf support, one for bperf
and one for bpf_profiler. Both are identified via evsel__is_bpf, based on which
perf events are enabled, but for the latter (bpf_profiler) a perf event is
required. Using evsel__is_bperf to check only bperf produces expected results:

    $ perf stat -e cycles -b 4 -I 10000 -vvv
    Control descriptor is not initialized
    ------------------------------------------------------------
    perf_event_attr:
      size                             136
      sample_type                      IDENTIFIER
      read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
      disabled                         1
      exclude_guest                    1
    ------------------------------------------------------------
    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 3
    ------------------------------------------------------------
    [...perf_event_attr for other CPUs...]
    ------------------------------------------------------------
    cycles: 309426 169009 169009
		time             counts unit events
	10.010091271             309426      cycles

The final numbers correspond (at least in the level of magnitude) to the
same metric obtained via bpftool.

Fixes: 112cb56164bc2108 ("perf stat: Introduce config stat.bpf-counter-events")
Reviewed-by: Song Liu &lt;song@kernel.org&gt;
Signed-off-by: Dmitrii Dolgov &lt;9erthalion6@gmail.com&gt;
Tested-by: Song Liu &lt;song@kernel.org&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Song Liu &lt;song@kernel.org&gt;
Link: https://lore.kernel.org/r/20230412182316.11628-1-9erthalion6@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>perf stat: Remove evsel metric_name/expr</title>
<updated>2023-02-03T16:54:21Z</updated>
<author>
<name>Ian Rogers</name>
</author>
<published>2023-01-26T23:36:37Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=6f8f98ab6c16101b0694ef7e70425ded9d7af30e'/>
<id>urn:sha1:6f8f98ab6c16101b0694ef7e70425ded9d7af30e</id>
<content type='text'>
Metrics are their own unit and these variables held broken metrics
previously and now just hold the value NULL. Remove code that used
these variables.

Reviewed-by: John Garry &lt;john.g.garry@oracle.com&gt;
Reviewed-by: Kajol Jain &lt;kjain@linux.ibm.com&gt;
Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Caleb Biggers &lt;caleb.biggers@intel.com&gt;
Cc: Florian Fischer &lt;florian.fischer@muhq.space&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@arm.com&gt;
Cc: Jing Zhang &lt;renyu.zj@linux.alibaba.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Kang Minchul &lt;tegongkang@gmail.com&gt;
Cc: Kim Phillips &lt;kim.phillips@amd.com&gt;
Cc: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Perry Taylor &lt;perry.taylor@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Cc: Rob Herring &lt;robh@kernel.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Xing Zhengjun &lt;zhengjun.xing@linux.intel.com&gt;
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230126233645.200509-8-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf build: Use libtraceevent from the system</title>
<updated>2022-12-14T14:16:12Z</updated>
<author>
<name>Ian Rogers</name>
</author>
<published>2022-12-05T22:59:39Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=378ef0f5d9d7f4652d7a40e0711e8b845ada1cbd'/>
<id>urn:sha1:378ef0f5d9d7f4652d7a40e0711e8b845ada1cbd</id>
<content type='text'>
Remove the LIBTRACEEVENT_DYNAMIC and LIBTRACEFS_DYNAMIC make command
line variables.

If libtraceevent isn't installed or NO_LIBTRACEEVENT=1 is passed to the
build, don't compile in libtraceevent and libtracefs support.

This also disables CONFIG_TRACE that controls "perf trace".

CONFIG_LIBTRACEEVENT is used to control enablement in Build/Makefiles,
HAVE_LIBTRACEEVENT is used in C code.

Without HAVE_LIBTRACEEVENT tracepoints are disabled and as such the
commands kmem, kwork, lock, sched and timechart are removed.  The
majority of commands continue to work including "perf test".

Committer notes:

Fixed up a tools/perf/util/Build reject and added:

  #include &lt;traceevent/event-parse.h&gt;

to tools/perf/util/scripting-engines/trace-event-perl.c.

Committer testing:

  $ rpm -qi libtraceevent-devel
  Name        : libtraceevent-devel
  Version     : 1.5.3
  Release     : 2.fc36
  Architecture: x86_64
  Install Date: Mon 25 Jul 2022 03:20:19 PM -03
  Group       : Unspecified
  Size        : 27728
  License     : LGPLv2+ and GPLv2+
  Signature   : RSA/SHA256, Fri 15 Apr 2022 02:11:58 PM -03, Key ID 999f7cbf38ab71f4
  Source RPM  : libtraceevent-1.5.3-2.fc36.src.rpm
  Build Date  : Fri 15 Apr 2022 10:57:01 AM -03
  Build Host  : buildvm-x86-05.iad2.fedoraproject.org
  Packager    : Fedora Project
  Vendor      : Fedora Project
  URL         : https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/
  Bug URL     : https://bugz.fedoraproject.org/libtraceevent
  Summary     : Development headers of libtraceevent
  Description :
  Development headers of libtraceevent-libs
  $

Default build:

  $ ldd ~/bin/perf | grep tracee
  	libtraceevent.so.1 =&gt; /lib64/libtraceevent.so.1 (0x00007f1dcaf8f000)
  $

  # perf trace -e sched:* --max-events 10
       0.000 migration/0/17 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, dest_cpu: 1)
       0.005 migration/0/17 sched:sched_wake_idle_without_ipi(cpu: 1)
       0.011 migration/0/17 sched:sched_switch(prev_comm: "", prev_pid: 17 (migration/0), prev_state: 1, next_comm: "", next_prio: 120)
       1.173 :0/0 sched:sched_wakeup(comm: "", pid: 3138 (gnome-terminal-), prio: 120)
       1.180 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 3138 (gnome-terminal-), next_prio: 120)
       0.156 migration/1/21 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, orig_cpu: 1, dest_cpu: 2)
       0.160 migration/1/21 sched:sched_wake_idle_without_ipi(cpu: 2)
       0.166 migration/1/21 sched:sched_switch(prev_comm: "", prev_pid: 21 (migration/1), prev_state: 1, next_comm: "", next_prio: 120)
       1.183 :0/0 sched:sched_wakeup(comm: "", pid: 1602985 (kworker/u16:0-f), prio: 120, target_cpu: 1)
       1.186 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 1602985 (kworker/u16:0-f), next_prio: 120)
  #

Had to tweak tools/perf/util/setup.py to make sure the python binding
shared object links with libtraceevent if -DHAVE_LIBTRACEEVENT is
present in CFLAGS.

Building with NO_LIBTRACEEVENT=1 uncovered some more build failures:

- Make building of data-convert-bt.c to CONFIG_LIBTRACEEVENT=y

- perf-$(CONFIG_LIBTRACEEVENT) += scripts/

- bpf_kwork.o needs also to be dependent on CONFIG_LIBTRACEEVENT=y

- The python binding needed some fixups and util/trace-event.c can't be
  built and linked with the python binding shared object, so remove it
  in tools/perf/util/setup.py and exclude it from the list of
  dependencies in the python/perf.so Makefile.perf target.

Building without libtraceevent-devel installed uncovered more build
failures:

- The python binding tools/perf/util/python.c was assuming that
  traceevent/parse-events.h was always available, which was the case
  when we defaulted to using the in-kernel tools/lib/traceevent/ files,
  now we need to enclose it under ifdef HAVE_LIBTRACEEVENT, just like
  the other parts of it that deal with tracepoints.

- We have to ifdef the rules in the Build files with
  CONFIG_LIBTRACEEVENT=y to build builtin-trace.c and
  tools/perf/trace/beauty/ as we only ifdef setting CONFIG_TRACE=y when
  setting NO_LIBTRACEEVENT=1 in the make command line, not when we don't
  detect libtraceevent-devel installed in the system. Simplification here
  to avoid these two ways of disabling builtin-trace.c and not having
  CONFIG_TRACE=y when libtraceevent-devel isn't installed is the clean
  way.

From Athira:

&lt;quote&gt;
tools/perf/arch/powerpc/util/Build
-perf-y += kvm-stat.o
+perf-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
&lt;/quote&gt;

Then, ditto for arm64 and s390, detected by container cross build tests.

- s/390 uses test__checkevent_tracepoint() that is now only available if
  HAVE_LIBTRACEEVENT is defined, enclose the callsite with ifder HAVE_LIBTRACEEVENT.

Also from Athira:

&lt;quote&gt;
With this change, I could successfully compile in these environment:
- Without libtraceevent-devel installed
- With libtraceevent-devel installed
- With “make NO_LIBTRACEEVENT=1”
&lt;/quote&gt;

Then, finally rename CONFIG_TRACEEVENT to CONFIG_LIBTRACEEVENT for
consistency with other libraries detected in tools/perf/.

Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Tested-by: Athira Rajeev &lt;atrajeev@linux.vnet.ibm.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20221205225940.3079667-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf cpumap: Tidy libperf includes</title>
<updated>2022-11-16T19:00:45Z</updated>
<author>
<name>Ian Rogers</name>
</author>
<published>2022-11-09T18:49:13Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=c4d9d95f84d7f4758db76f358b03a0d6809c929b'/>
<id>urn:sha1:c4d9d95f84d7f4758db76f358b03a0d6809c929b</id>
<content type='text'>
Use public API when possible, don't include internal API in header
files in evsel.h. Fix any related breakages.

Committer note:

There was one missing case, when building for arm64:

  arch/arm64/util/pmu.c: In function 'pmu_events_table__find':
  arch/arm64/util/pmu.c:18:30: error: invalid use of undefined type 'struct perf_cpu_map'
     18 |                 if (pmu-&gt;cpus-&gt;nr != cpu__max_cpu().cpu)
        |                              ^~

Fix it by adding one more exception, including &lt;internal/cpumap.h&gt;

Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andrii Nakryiko &lt;andrii.nakryiko@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Nicolas Schier &lt;nicolas@fjasle.eu&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20221109184914.1357295-14-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf pmu: Remove mostly unused 'struct perf_pmu' 'is_hybrid' member</title>
<updated>2022-11-15T13:15:24Z</updated>
<author>
<name>Ian Rogers</name>
</author>
<published>2022-11-14T21:07:14Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=e5f4afbe395f1248e7501d470118a2a947fe87e6'/>
<id>urn:sha1:e5f4afbe395f1248e7501d470118a2a947fe87e6</id>
<content type='text'>
Replace usage with perf_pmu__is_hybrid().

Suggested-by: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Caleb Biggers &lt;caleb.biggers@intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kajol Jain &lt;kjain@linux.ibm.com&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Perry Taylor &lt;perry.taylor@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Cc: Rob Herring &lt;robh@kernel.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Weilin Wang &lt;weilin.wang@intel.com&gt;
Cc: Xin Gao &lt;gaoxin@cdjrlc.com&gt;
Cc: Xing Zhengjun &lt;zhengjun.xing@linux.intel.com&gt;
Link: http://lore.kernel.org/lkml/20221114210723.2749751-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf record: Set PERF_FORMAT_LOST by default</title>
<updated>2022-10-04T11:55:20Z</updated>
<author>
<name>Namhyung Kim</name>
</author>
<published>2022-09-01T19:57:36Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=e17f343c3ba1b317574a4218c631547bb09e72bf'/>
<id>urn:sha1:e17f343c3ba1b317574a4218c631547bb09e72bf</id>
<content type='text'>
As we want to see the number of lost samples in the perf report, set the
LOST format when it configs evsel.  On old kernels, it'd fallback to
disable it.

Reviewed-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20220901195739.668604-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf evsel: Add arch_evsel__hw_name()</title>
<updated>2022-07-29T16:41:19Z</updated>
<author>
<name>Kan Liang</name>
</author>
<published>2022-07-21T06:57:03Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=ff4207f79307dc4910a27771e4306e1a64fde3e1'/>
<id>urn:sha1:ff4207f79307dc4910a27771e4306e1a64fde3e1</id>
<content type='text'>
The commit 55bcf6ef314ae8ba ("perf: Extend PERF_TYPE_HARDWARE and
PERF_TYPE_HW_CACHE") extends the two types to become PMU aware types for
a hybrid system. However, current evsel__hw_name doesn't take the PMU
type into account. It mistakenly returns the "unknown-hardware" for the
hardware event with a specific PMU type.

Add an arch specific arch_evsel__hw_name() to specially handle the PMU
aware hardware event.

Currently, the extend PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE is only
supported by X86. Only implement the specific arch_evsel__hw_name() for
X86 in the patch.

Nothing is changed for the other archs.

Signed-off-by: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Acked-by: Ian Rogers &lt;irogers@google.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20220721065706.2886112-3-zhengjun.xing@linux.intel.com
Signed-off-by: Xing Zhengjun &lt;zhengjun.xing@linux.intel.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tools: Factor out evsel__id_hdr_size()</title>
<updated>2022-07-20T14:07:48Z</updated>
<author>
<name>Adrian Hunter</name>
</author>
<published>2022-07-11T09:31:48Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=0a64de04c94ad4285120bed0dfb382ea98d6d499'/>
<id>urn:sha1:0a64de04c94ad4285120bed0dfb382ea98d6d499</id>
<content type='text'>
Factor out evsel__id_hdr_size() so it can be reused.

This is needed by perf inject. When injecting events from a guest perf.data
file, there is a possibility that the sample ID numbers conflict. To
re-write an ID sample, the old one needs to be removed first, which means
determining how big it is with evsel__id_hdr_size() and then subtracting
that from the event size.

Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf record ibs: Warn about sampling period skew</title>
<updated>2022-06-24T16:18:22Z</updated>
<author>
<name>Ravi Bangoria</name>
</author>
<published>2022-06-04T04:45:12Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=9ab95b0b15a092abb7c3309f3580f572a041f9ab'/>
<id>urn:sha1:9ab95b0b15a092abb7c3309f3580f572a041f9ab</id>
<content type='text'>
Samples without an L3 miss are discarded and counter is reset with
random value (between 1-15 for fetch PMU and 1-127 for op PMU) when IBS
L3 miss filtering is enabled. This causes a sampling period skew but
there is no way to reconstruct aggregated sampling period. So print a
warning at perf record if user sets l3missonly=1.

Ex:

  # perf record -c 10000 -C 0 -e ibs_op/l3missonly=1/
  WARNING: Hw internally resets sampling period when L3 Miss Filtering is enabled
  and tagged operation does not cause L3 Miss. This causes sampling period skew.

Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Acked-by: Ian Rogers &lt;irogers@google.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Ananth Narayan &lt;ananth.narayan@amd.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: James Clark &lt;james.clark@arm.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Kim Phillips &lt;kim.phillips@amd.com&gt;
Cc: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Robert Richter &lt;rrichter@amd.com&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Santosh Shukla &lt;santosh.shukla@amd.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: like.xu.linux@gmail.com
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20220604044519.594-2-ravi.bangoria@amd.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
</feed>
