<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/tools/perf/util/event.c, branch master</title>
<subtitle>Hosts the 0x221E linux distro kernel.</subtitle>
<id>https://universe.0xinfinity.dev/distro/kernel/atom?h=master</id>
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<updated>2026-01-23T19:58:39Z</updated>
<entry>
<title>perf map_symbol: Switch from holding maps to holding thread</title>
<updated>2026-01-23T19:58:39Z</updated>
<author>
<name>Ian Rogers</name>
<email>irogers@google.com</email>
</author>
<published>2026-01-22T21:35:14Z</published>
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<id>urn:sha1:c4e3a00356fffb20c03bd9609083afb1dc4a2edf</id>
<content type='text'>
maps may belong to &gt;1 thread. In contexts like symbolization
information from the thread may be useful, such as the ELF machine.

As the maps can be gained from the thread switch from holding maps in
struct map_symbol to holding the thread.

Holding the maps in addr_location is also redundant, switch this to
using thread__maps.

Reviewed-by: James Clark &lt;james.clark@linaro.org&gt;
Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Cc: Aditya Bodkhe &lt;aditya.b1@linux.ibm.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Cc: Athira Rajeev &lt;atrajeev@linux.ibm.com&gt;
Cc: Bill Wendling &lt;morbo@google.com&gt;
Cc: Dr. David Alan Gilbert &lt;linux@treblig.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Howard Chu &lt;howardchu95@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Julia Lawall &lt;Julia.Lawall@inria.fr&gt;
Cc: Justin Stitt &lt;justinstitt@google.com&gt;
Cc: Krzysztof Łopatowski &lt;krzysztof.m.lopatowski@gmail.com&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;nick.desaulniers+lkml@gmail.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;pjw@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sergei Trofimovich &lt;slyich@gmail.com&gt;
Cc: Shimin Guo &lt;shimin.guo@skydio.com&gt;
Cc: Suchit Karunakaran &lt;suchitkarunakaran@gmail.com&gt;
Cc: Thomas Falcon &lt;thomas.falcon@intel.com&gt;
Cc: Tianyou Li &lt;tianyou.li@intel.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Zecheng Li &lt;zecheng@google.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf sched stats: Add schedstat v17 support</title>
<updated>2026-01-22T15:31:51Z</updated>
<author>
<name>Swapnil Sapkal</name>
<email>swapnil.sapkal@amd.com</email>
</author>
<published>2026-01-19T17:58:27Z</published>
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<id>urn:sha1:805da27252a290984782abfdb313a78e7c157369</id>
<content type='text'>
The /proc/schedstat file output is standardized with version number.

Add support to record and raw dump v17 version layout.

Version 17 of schedstats removed 'lb_imbalance' field as it has no
significance anymore and instead added more relevant fields namely
'lb_imbalance_load', 'lb_imbalance_util', 'lb_imbalance_task' and
'lb_imbalance_misfit'.

The domain field prints the name of the corresponding sched domain from
this version onwards.

Co-developed-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Signed-off-by: Swapnil Sapkal &lt;swapnil.sapkal@amd.com&gt;
Tested-by: Chen Yu &lt;yu.c.chen@intel.com&gt;
Acked-by: Ian Rogers &lt;irogers@google.com&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Anubhav Shelat &lt;ashelat@redhat.com&gt;
Cc: Ben Gainey &lt;ben.gainey@arm.com&gt;
Cc: Blake Jones &lt;blakejones@google.com&gt;
Cc: Chun-Tse Shao &lt;ctshao@google.com&gt;
Cc: David Vernet &lt;void@manifault.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Dr. David Alan Gilbert &lt;linux@treblig.org&gt;
Cc: Gautham Shenoy &lt;gautham.shenoy@amd.com&gt;
Cc: Graham Woodward &lt;graham.woodward@arm.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: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: K Prateek Nayak &lt;kprateek.nayak@amd.com&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Leo Yan &lt;leo.yan@arm.com&gt;
Cc: Madadi Vineeth Reddy &lt;vineethr@linux.ibm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Santosh Shukla &lt;santosh.shukla@amd.com&gt;
Cc: Shrikanth Hegde &lt;sshegde@linux.ibm.com&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Thomas Falcon &lt;thomas.falcon@intel.com&gt;
Cc: Tim Chen &lt;tim.c.chen@linux.intel.com&gt;
Cc: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Cc: Yang Jihong &lt;yangjihong@bytedance.com&gt;
Cc: Yujie Liu &lt;yujie.liu@intel.com&gt;
Cc: Zhongqiu Han &lt;quic_zhonhan@quicinc.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf sched stats: Add schedstat v16 support</title>
<updated>2026-01-22T15:30:16Z</updated>
<author>
<name>Swapnil Sapkal</name>
<email>swapnil.sapkal@amd.com</email>
</author>
<published>2026-01-19T17:58:26Z</published>
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<id>urn:sha1:55657d7ac8caa98c7c0ef241bf64e176db899b4d</id>
<content type='text'>
The /proc/schedstat file output is standardized with version number.

Add support to record and raw dump v16 version layout.

Version 16 of schedstats changed the order of definitions within 'enum
cpu_idle_type', which changed the order of [CPU_MAX_IDLE_TYPES] columns
in show_schedstat().

In particular the position of CPU_IDLE and __CPU_NOT_IDLE changed
places.

Co-developed-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Signed-off-by: Swapnil Sapkal &lt;swapnil.sapkal@amd.com&gt;
Tested-by: Chen Yu &lt;yu.c.chen@intel.com&gt;
Tested-by: James Clark &lt;james.clark@linaro.org&gt;
Acked-by: Ian Rogers &lt;irogers@google.com&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Anubhav Shelat &lt;ashelat@redhat.com&gt;
Cc: Ben Gainey &lt;ben.gainey@arm.com&gt;
Cc: Blake Jones &lt;blakejones@google.com&gt;
Cc: Chun-Tse Shao &lt;ctshao@google.com&gt;
Cc: David Vernet &lt;void@manifault.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Dr. David Alan Gilbert &lt;linux@treblig.org&gt;
Cc: Gautham Shenoy &lt;gautham.shenoy@amd.com&gt;
Cc: Graham Woodward &lt;graham.woodward@arm.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: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: K Prateek Nayak &lt;kprateek.nayak@amd.com&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Leo Yan &lt;leo.yan@arm.com&gt;
Cc: Madadi Vineeth Reddy &lt;vineethr@linux.ibm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Santosh Shukla &lt;santosh.shukla@amd.com&gt;
Cc: Shrikanth Hegde &lt;sshegde@linux.ibm.com&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Thomas Falcon &lt;thomas.falcon@intel.com&gt;
Cc: Tim Chen &lt;tim.c.chen@linux.intel.com&gt;
Cc: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Cc: Yang Jihong &lt;yangjihong@bytedance.com&gt;
Cc: Yujie Liu &lt;yujie.liu@intel.com&gt;
Cc: Zhongqiu Han &lt;quic_zhonhan@quicinc.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf sched stats: Add record and rawdump support</title>
<updated>2026-01-22T15:29:28Z</updated>
<author>
<name>Swapnil Sapkal</name>
<email>swapnil.sapkal@amd.com</email>
</author>
<published>2026-01-19T17:58:25Z</published>
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<id>urn:sha1:c3030995f23b3d35f94b9bc4375706ec5916fd55</id>
<content type='text'>
Define new, perf tool only, sample types and their layouts. Add logic
to parse /proc/schedstat, convert it to perf sample format and save
samples to perf.data file with `perf sched stats record` command.

Also add logic to read perf.data file, interpret schedstat samples and
print rawdump of samples with `perf script -D`.

Note that, /proc/schedstat file output is standardized with version
number. The patch supports v15 but older or newer version can be added
easily.

Co-developed-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Signed-off-by: Swapnil Sapkal &lt;swapnil.sapkal@amd.com&gt;
Tested-by: Chen Yu &lt;yu.c.chen@intel.com&gt;
Tested-by: James Clark &lt;james.clark@linaro.org&gt;
Acked-by: Ian Rogers &lt;irogers@google.com&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Anubhav Shelat &lt;ashelat@redhat.com&gt;
Cc: Ben Gainey &lt;ben.gainey@arm.com&gt;
Cc: Blake Jones &lt;blakejones@google.com&gt;
Cc: Chun-Tse Shao &lt;ctshao@google.com&gt;
Cc: David Vernet &lt;void@manifault.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Dr. David Alan Gilbert &lt;linux@treblig.org&gt;
Cc: Gautham Shenoy &lt;gautham.shenoy@amd.com&gt;
Cc: Graham Woodward &lt;graham.woodward@arm.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: Juri Lelli &lt;juri.lelli@redhat.com&gt;
Cc: K Prateek Nayak &lt;kprateek.nayak@amd.com&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Leo Yan &lt;leo.yan@arm.com&gt;
Cc: Madadi Vineeth Reddy &lt;vineethr@linux.ibm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Santosh Shukla &lt;santosh.shukla@amd.com&gt;
Cc: Shrikanth Hegde &lt;sshegde@linux.ibm.com&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Thomas Falcon &lt;thomas.falcon@intel.com&gt;
Cc: Tim Chen &lt;tim.c.chen@linux.intel.com&gt;
Cc: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Cc: Yang Jihong &lt;yangjihong@bytedance.com&gt;
Cc: Yujie Liu &lt;yujie.liu@intel.com&gt;
Cc: Zhongqiu Han &lt;quic_zhonhan@quicinc.com&gt;
[ PRIu64 needs uint64_t, not 'unsigned long' to work on both 32-bit and 64-bit ]
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tools: Minimal DEFERRED_CALLCHAIN support</title>
<updated>2025-12-03T00:13:32Z</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2025-11-20T23:48:00Z</published>
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<id>urn:sha1:f4e3381648be205365cb475512ee536e108e060e</id>
<content type='text'>
Add a new event type for deferred callchains and a new callback for the
struct perf_tool.  For now it doesn't actually handle the deferred
callchains but it just marks the sample if it has the PERF_CONTEXT_
USER_DEFFERED in the callchain array.

At least, perf report can dump the raw data with this change.  Actually
this requires the next commit to enable attr.defer_callchain, but if you
already have a data file, it'll show the following result.

  $ perf report -D
  ...
  0x2158@perf.data [0x40]: event: 22
  .
  . ... raw event: size 64 bytes
  .  0000:  16 00 00 00 02 00 40 00 06 00 00 00 0b 00 00 00  ......@.........
  .  0010:  03 00 00 00 00 00 00 00 a7 7f 33 fe 18 7f 00 00  ..........3.....
  .  0020:  0f 0e 33 fe 18 7f 00 00 48 14 33 fe 18 7f 00 00  ..3.....H.3.....
  .  0030:  08 09 00 00 08 09 00 00 e6 7a e7 35 1c 00 00 00  .........z.5....

  121163447014 0x2158 [0x40]: PERF_RECORD_CALLCHAIN_DEFERRED(IP, 0x2): 2312/2312: 0xb00000006
  ... FP chain: nr:3
  .....  0: 00007f18fe337fa7
  .....  1: 00007f18fe330e0f
  .....  2: 00007f18fe331448
  : unhandled!

Reviewed-by: Ian Rogers &lt;irogers@google.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
</entry>
<entry>
<title>perf build-id: Change sprintf functions to snprintf</title>
<updated>2025-07-25T17:37:13Z</updated>
<author>
<name>Ian Rogers</name>
<email>irogers@google.com</email>
</author>
<published>2025-07-24T16:32:43Z</published>
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<id>urn:sha1:fccaaf6fbbc59910edcf276f97a5b2ef5778c55e</id>
<content type='text'>
Pass in a size argument rather than implying all build id strings must
be SBUILD_ID_SIZE.

Signed-off-by: Ian Rogers &lt;irogers@google.com&gt;
Link: https://lore.kernel.org/r/20250724163302.596743-4-irogers@google.com
[ fixed some build errors ]
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
</entry>
<entry>
<title>perf tools: display the new PERF_RECORD_BPF_METADATA event</title>
<updated>2025-06-20T21:48:56Z</updated>
<author>
<name>Blake Jones</name>
<email>blakejones@google.com</email>
</author>
<published>2025-06-12T19:49:38Z</published>
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<id>urn:sha1:f19860ea9477f5ac33775cc0a602c7d54188c00a</id>
<content type='text'>
Here's some example "perf script -D" output for the new event type. The
": unhandled!" message is from tool.c, analogous to other behavior there.
I've elided some rows with all NUL characters for brevity, and I wrapped
one of the &gt;75-column lines to fit in the commit guidelines.

0x50fc8@perf.data [0x260]: event: 84
.
. ... raw event: size 608 bytes
.  0000:  54 00 00 00 00 00 60 02 62 70 66 5f 70 72 6f 67  T.....`.bpf_prog
.  0010:  5f 31 65 30 61 32 65 33 36 36 65 35 36 66 31 61  _1e0a2e366e56f1a
.  0020:  32 5f 70 65 72 66 5f 73 61 6d 70 6c 65 5f 66 69  2_perf_sample_fi
.  0030:  6c 74 65 72 00 00 00 00 00 00 00 00 00 00 00 00  lter............
.  0040:  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
[...]
.  0110:  74 65 73 74 5f 76 61 6c 75 65 00 00 00 00 00 00  test_value......
.  0120:  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
[...]
.  0150:  34 32 00 00 00 00 00 00 00 00 00 00 00 00 00 00  42..............
.  0160:  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
[...]

0 0x50fc8 [0x260]: PERF_RECORD_BPF_METADATA \
      prog bpf_prog_1e0a2e366e56f1a2_perf_sample_filter
  entry 0:           test_value = 42
: unhandled!

Signed-off-by: Blake Jones &lt;blakejones@google.com&gt;
Link: https://lore.kernel.org/r/20250612194939.162730-5-blakejones@google.com
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
</entry>
<entry>
<title>perf script: Print PERF_AUX_FLAG_COLLISION flag</title>
<updated>2025-05-28T18:08:25Z</updated>
<author>
<name>Leo Yan</name>
<email>leo.yan@arm.com</email>
</author>
<published>2025-05-28T15:35:19Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=e8718f9866e5aa25724bc85a518ed5d6ad9d4bb4'/>
<id>urn:sha1:e8718f9866e5aa25724bc85a518ed5d6ad9d4bb4</id>
<content type='text'>
Print out the collision flag for AUX trace data. This is helpful for
inspecting sample collisions.

After:

  0x217b60@/data_nvme1n1/niayan01/upstream/perf.data [0x40]: event: 11
  .
  . ... raw event: size 64 bytes
  .  0000:  0b 00 00 00 00 00 40 00 d2 ef 3f 00 00 00 00 00  ......@...?.....
  .  0010:  ff 0f 00 00 00 00 00 00 08 00 00 00 00 00 00 00  ................
  .  0020:  1c 01 00 00 1c 01 00 00 10 bf 38 d6 11 01 00 00  ..........8.....
  .  0030:  03 00 00 00 00 00 00 00 06 00 00 00 00 00 00 00  ................

  3 1176120114960 0x217b60 [0x40]: PERF_RECORD_AUX offset: 0x3fefd2 size: 0xfff flags: 0x8 [C]

The added character '[C]' indicates the collision.

Signed-off-by: Leo Yan &lt;leo.yan@arm.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Link: https://lore.kernel.org/r/20250528153519.188644-1-leo.yan@arm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf record: Add 8-byte aligned event type PERF_RECORD_COMPRESSED2</title>
<updated>2025-05-16T20:31:40Z</updated>
<author>
<name>Chun-Tse Shao</name>
<email>ctshao@google.com</email>
</author>
<published>2025-03-03T18:32:40Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=208c0e16834472bb3a4b456a69dbdd1ad05eab49'/>
<id>urn:sha1:208c0e16834472bb3a4b456a69dbdd1ad05eab49</id>
<content type='text'>
The original PERF_RECORD_COMPRESS is not 8-byte aligned, which can cause
asan runtime error:

  # Build with asan
  $ make -C tools/perf O=/tmp/perf DEBUG=1 EXTRA_CFLAGS="-O0 -g -fno-omit-frame-pointer -fsanitize=undefined"
  # Test success with many asan runtime errors:
  $ /tmp/perf/perf test "Zstd perf.data compression/decompression" -vv
   83: Zstd perf.data compression/decompression:
  ...
  util/session.c:1959:13: runtime error: member access within misaligned address 0x7f69e3f99653 for type 'union perf_event', which requires 13 byte alignment
  0x7f69e3f99653: note: pointer points here
   d0  3a 50 69 44 00 00 00 00  00 08 00 bb 07 00 00 00  00 00 00 44 00 00 00 00  00 00 00 ff 07 00 00
                ^
  util/session.c:2163:22: runtime error: member access within misaligned address 0x7f69e3f99653 for type 'union perf_event', which requires 8 byte alignment
  0x7f69e3f99653: note: pointer points here
   d0  3a 50 69 44 00 00 00 00  00 08 00 bb 07 00 00 00  00 00 00 44 00 00 00 00  00 00 00 ff 07 00 00
                ^
  ...

Since there is no way to align compressed data in zstd compression, this
patch add a new event type `PERF_RECORD_COMPRESSED2`, which adds a field
`data_size` to specify the actual compressed data size.

The `header.size` contains the total record size, including the padding
at the end to make it 8-byte aligned.

Tested with `Zstd perf.data compression/decompression`

Signed-off-by: Chun-Tse Shao &lt;ctshao@google.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ben Gainey &lt;ben.gainey@arm.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Leo Yan &lt;leo.yan@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Nick Terrell &lt;terrelln@fb.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20250303183646.327510-1-ctshao@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf report: Add latency output field</title>
<updated>2025-02-18T22:04:32Z</updated>
<author>
<name>Dmitry Vyukov</name>
<email>dvyukov@google.com</email>
</author>
<published>2025-02-13T09:08:18Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=ee1cffbe24e7dc129c737a5f433b35e2ce0bdd78'/>
<id>urn:sha1:ee1cffbe24e7dc129c737a5f433b35e2ce0bdd78</id>
<content type='text'>
Latency output field is similar to overhead, but represents overhead for
latency rather than CPU consumption. It's re-scaled from overhead by dividing
weight by the current parallelism level at the time of the sample.
It effectively models profiling with 1 sample taken per unit of wall-clock
time rather than unit of CPU time.

Signed-off-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Reviewed-by: Andi Kleen &lt;ak@linux.intel.com&gt;
Link: https://lore.kernel.org/r/b6269518758c2166e6ffdc2f0e24cfdecc8ef9c1.1739437531.git.dvyukov@google.com
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
</entry>
</feed>
