<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/git/stable/linux.git/tools/perf, branch linux-6.0.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<id>https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-6.0.y</id>
<link rel='self' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-6.0.y'/>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/'/>
<updated>2023-01-12T11:00:41+00:00</updated>
<entry>
<title>perf stat: Fix handling of --for-each-cgroup with --bpf-counters to match non BPF mode</title>
<updated>2023-01-12T11:00:41+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2023-01-04T06:44:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=314f50ce4e82338fc47a4ca68a53e5d0ebd6b24d'/>
<id>urn:sha1:314f50ce4e82338fc47a4ca68a53e5d0ebd6b24d</id>
<content type='text'>
[ Upstream commit 54b353a20c7e8be98414754f5aff98c8a68fcc1f ]

The --for-each-cgroup can have the same cgroup multiple times, but this
confuses BPF counters (since they have the same cgroup id), making only
the last cgroup events to be counted.

Let's check the cgroup name before adding a new entry to the cgroups
list.

Before:

  $ sudo ./perf stat -a --bpf-counters --for-each-cgroup /,/ sleep 1

   Performance counter stats for 'system wide':

       &lt;not counted&gt; msec cpu-clock                        /
       &lt;not counted&gt;      context-switches                 /
       &lt;not counted&gt;      cpu-migrations                   /
       &lt;not counted&gt;      page-faults                      /
       &lt;not counted&gt;      cycles                           /
       &lt;not counted&gt;      instructions                     /
       &lt;not counted&gt;      branches                         /
       &lt;not counted&gt;      branch-misses                    /
            8,016.04 msec cpu-clock                        /                #    7.998 CPUs utilized
               6,152      context-switches                 /                #  767.461 /sec
                 250      cpu-migrations                   /                #   31.187 /sec
                 442      page-faults                      /                #   55.139 /sec
         613,111,487      cycles                           /                #    0.076 GHz
         280,599,604      instructions                     /                #    0.46  insn per cycle
          57,692,724      branches                         /                #    7.197 M/sec
           3,385,168      branch-misses                    /                #    5.87% of all branches

         1.002220125 seconds time elapsed

After it becomes similar to the non-BPF mode:

  $ sudo ./perf stat -a --bpf-counters --for-each-cgroup /,/  sleep 1

   Performance counter stats for 'system wide':

            8,013.38 msec cpu-clock                        /                #    7.998 CPUs utilized
               6,859      context-switches                 /                #  855.944 /sec
                 334      cpu-migrations                   /                #   41.680 /sec
                 345      page-faults                      /                #   43.053 /sec
         782,326,119      cycles                           /                #    0.098 GHz
         471,645,724      instructions                     /                #    0.60  insn per cycle
          94,963,430      branches                         /                #   11.851 M/sec
           3,685,511      branch-misses                    /                #    3.88% of all branches

         1.001864539 seconds time elapsed

Committer notes:

As a reminder, to test with BPF counters one has to use BUILD_BPF_SKEL=1
in the make command line and have clang/llvm installed when building
perf, otherwise the --bpf-counters option will not be available:

  # perf stat -a --bpf-counters --for-each-cgroup /,/ sleep 1
  Error: unknown option `bpf-counters'

   Usage: perf stat [&lt;options&gt;] [&lt;command&gt;]

      -a, --all-cpus        system-wide collection from all CPUs
  &lt;SNIP&gt;
  #

Fixes: bb1c15b60b981d10 ("perf stat: Support regex pattern in --for-each-cgroup")
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: bpf@vger.kernel.org
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: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Link: https://lore.kernel.org/r/20230104064402.1551516-5-namhyung@kernel.org
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: Fix handling of unsupported cgroup events when using BPF counters</title>
<updated>2023-01-12T11:00:41+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2023-01-04T06:44:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c1bb59435614ccde0caaba91564bbe050b05bf53'/>
<id>urn:sha1:c1bb59435614ccde0caaba91564bbe050b05bf53</id>
<content type='text'>
[ Upstream commit 2d656b0f81b22101db0447f890e39fdd736b745e ]

When --for-each-cgroup option is used, it fails when any of events is
not supported and exits immediately.  This is not how 'perf stat'
handles unsupported events.

Let's ignore the failure and proceed with others so that the output is
similar to when BPF counters are not used:

Before:

  $ sudo ./perf stat -a --bpf-counters -e L1-icache-loads,L1-dcache-loads --for-each-cgroup system.slice,user.slice sleep 1
  Failed to open first cgroup events
  $

After it shows output similat to when --bpf-counters isn't specified:

  $ sudo ./perf stat -a --bpf-counters -e L1-icache-loads,L1-dcache-loads --for-each-cgroup system.slice,user.slice sleep 1

   Performance counter stats for 'system wide':

     &lt;not supported&gt;      L1-icache-loads                  system.slice
          29,892,418      L1-dcache-loads                  system.slice
     &lt;not supported&gt;      L1-icache-loads                  user.slice
          52,497,220      L1-dcache-loads                  user.slice
  $

Fixes: 944138f048f7d759 ("perf stat: Enable BPF counter with --for-each-cgroup")
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&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;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Link: https://lore.kernel.org/r/20230104064402.1551516-4-namhyung@kernel.org
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 lock contention: Fix core dump related to not finding the "__sched_text_end" symbol on s/390</title>
<updated>2023-01-12T11:00:40+00:00</updated>
<author>
<name>Thomas Richter</name>
<email>tmricht@linux.ibm.com</email>
</author>
<published>2022-12-30T10:26:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1277e2c595704fcbd3ec09e2f63a477d55b14646'/>
<id>urn:sha1:1277e2c595704fcbd3ec09e2f63a477d55b14646</id>
<content type='text'>
[ Upstream commit d8d85ce86dc82de4f88b821a78f533b9d5b22a45 ]

The test case perf lock contention dumps core on s390. Run the following
commands:

  # ./perf lock record -- ./perf bench sched messaging
  # Running 'sched/messaging' benchmark:
  # 20 sender and receiver processes per group
  # 10 groups == 400 processes run

      Total time: 2.799 [sec]
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.073 MB perf.data (100 samples) ]
  #
  # ./perf lock contention
  Segmentation fault (core dumped)
  #

The function call stack is lengthy, here are the top 5 functions:

  # gdb ./perf core.24048
  GNU gdb (GDB) Fedora Linux 12.1-6.fc37
  Core was generated by `./perf lock contention'.
  Program terminated with signal SIGSEGV, Segmentation fault.
  #0  0x00000000011dd25c in machine__is_lock_function (machine=0x3029e28, addr=1789230) at util/machine.c:3356
         3356 machine-&gt;sched.text_end = kmap-&gt;unmap_ip(kmap, sym-&gt;start);

 (gdb) where
  #0  0x00000000011dd25c in machine__is_lock_function (machine=0x3029e28, addr=1789230) at util/machine.c:3356
  #1  0x000000000109f244 in callchain_id (evsel=0x30313e0, sample=0x3ffea4f77d0) at builtin-lock.c:957
  #2  0x000000000109e094 in get_key_by_aggr_mode (key=0x3ffea4f7290, addr=27758136, evsel=0x30313e0, sample=0x3ffea4f77d0) at builtin-lock.c:586
  #3  0x000000000109f4d0 in report_lock_contention_begin_event (evsel=0x30313e0, sample=0x3ffea4f77d0) at builtin-lock.c:1004
  #4  0x00000000010a00ae in evsel__process_contention_begin (evsel=0x30313e0, sample=0x3ffea4f77d0) at builtin-lock.c:1254
  #5  0x00000000010a0e14 in process_sample_event (tool=0x3ffea4f8480, event=0x3ff85601ef8, sample=0x3ffea4f77d0, evsel=0x30313e0, machine=0x3029e28) at builtin-lock.c:1464
  .....

The issue is in function machine__is_lock_function() in file
./util/machine.c lines 3355:

   /* should not fail from here */
   sym = machine__find_kernel_symbol_by_name(machine, "__sched_text_end", &amp;kmap);
   machine-&gt;sched.text_end = kmap-&gt;unmap_ip(kmap, sym-&gt;start)

On s390 the symbol __sched_text_end is *NOT* in the symbol list and the
resulting pointer sym is set to NULL. The sym-&gt;start is then a NULL pointer
access and generates the core dump.

The reason why __sched_text_end is not in the symbol list on s390 is
simple:

When the symbol list is created at perf start up with function calls

  dso__load
  +--&gt; dso__load_vmlinux_path
       +--&gt; dso__load_vmlinux
            +--&gt; dso__load_sym
	         +--&gt; dso__load_sym_internal (reads kernel symbols)
		 +--&gt; symbols__fixup_end
		 +--&gt; symbols__fixup_duplicate

The issue is in function symbols__fixup_duplicate(). It deletes all
symbols with have the same address. On s390:

  # nm -g  ~/linux/vmlinux| fgrep c68390
  0000000000c68390 T __cpuidle_text_start
  0000000000c68390 T __sched_text_end
  #

two symbols have identical addresses and __sched_text_end is considered
duplicate (in ascending sort order) and removed from the symbol list.
Therefore it is missing and an invalid pointer reference occurs.  The
code checks for symbol __sched_text_start and when it exists assumes
symbol __sched_text_end is also in the symbol table. However this is not
the case on s390.

Same situation exists for symbol __lock_text_start:

0000000000c68770 T __cpuidle_text_end
0000000000c68770 T __lock_text_start

This symbol is also removed from the symbol table but used in function
machine__is_lock_function().

To fix this and keep duplicate symbols in the symbol table, set
symbol_conf.allow_aliases to true. This prevents the removal of
duplicate symbols in function symbols__fixup_duplicate().

Output After:

 # ./perf lock contention
 contended total wait  max wait  avg wait    type   caller

        48   124.39 ms 123.99 ms   2.59 ms rwsem:W unlink_anon_vmas+0x24a
        47    83.68 ms  83.26 ms   1.78 ms rwsem:W free_pgtables+0x132
         5    41.22 us  10.55 us   8.24 us rwsem:W free_pgtables+0x140
         4    40.12 us  20.55 us  10.03 us rwsem:W copy_process+0x1ac8
 #

Fixes: 0d2997f750d1de39 ("perf lock: Look up callchain for the contended locks")
Signed-off-by: Thomas Richter &lt;tmricht@linux.ibm.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Sumanth Korikkar &lt;sumanthk@linux.ibm.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20221230102627.2410847-1-tmricht@linux.ibm.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 tools: Fix resources leak in perf_data__open_dir()</title>
<updated>2023-01-12T11:00:40+00:00</updated>
<author>
<name>Miaoqian Lin</name>
<email>linmq006@gmail.com</email>
</author>
<published>2022-12-29T09:09:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d89805f8fdedcf8efd645ff2e9d81d15a3b43313'/>
<id>urn:sha1:d89805f8fdedcf8efd645ff2e9d81d15a3b43313</id>
<content type='text'>
[ Upstream commit 0a6564ebd953c4590663c9a3c99a3ea9920ade6f ]

In perf_data__open_dir(), opendir() opens the directory stream.  Add
missing closedir() to release it after use.

Fixes: eb6176709b235b96 ("perf data: Add perf_data__open_dir_data function")
Reviewed-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Signed-off-by: Miaoqian Lin &lt;linmq006@gmail.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Alexey Bayduraev &lt;alexey.v.bayduraev@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.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: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20221229090903.1402395-1-linmq006@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 probe: Fix to get the DW_AT_decl_file and DW_AT_call_file as unsinged data</title>
<updated>2023-01-12T11:00:28+00:00</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2022-11-05T03:01:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=749fa62e49279876e11c5fb85720b7befb3f4a9d'/>
<id>urn:sha1:749fa62e49279876e11c5fb85720b7befb3f4a9d</id>
<content type='text'>
[ Upstream commit a9dfc46c67b52ad43b8e335e28f4cf8002c67793 ]

DWARF version 5 standard Sec 2.14 says that

  Any debugging information entry representing the declaration of an object,
  module, subprogram or type may have DW_AT_decl_file, DW_AT_decl_line and
  DW_AT_decl_column attributes, each of whose value is an unsigned integer
  constant.

So it should be an unsigned integer data. Also, even though the standard
doesn't clearly say the DW_AT_call_file is signed or unsigned, the
elfutils (eu-readelf) interprets it as unsigned integer data and it is
natural to handle it as unsigned integer data as same as DW_AT_decl_file.
This changes the DW_AT_call_file as unsigned integer data too.

Fixes: 3f4460a28fb2f73d ("perf probe: Filter out redundant inline-instances")
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Masami Hiramatsu &lt;masami.hiramatsu.pt@hitachi.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: stable@vger.kernel.org
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Link: https://lore.kernel.org/r/166761727445.480106.3738447577082071942.stgit@devnote3
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 probe: Use dwarf_attr_integrate as generic DWARF attr accessor</title>
<updated>2023-01-12T11:00:28+00:00</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2022-11-01T13:48:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b0d8f117079e1d0c6c067f41ec21610857086759'/>
<id>urn:sha1:b0d8f117079e1d0c6c067f41ec21610857086759</id>
<content type='text'>
[ Upstream commit f828929ab7f0dc3353e4a617f94f297fa8f3dec3 ]

Use dwarf_attr_integrate() instead of dwarf_attr() for generic attribute
acccessor functions, so that it can find the specified attribute from
abstact origin DIE etc.

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Link: https://lore.kernel.org/r/166731051988.2100653.13595339994343449770.stgit@devnote3
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Stable-dep-of: a9dfc46c67b5 ("perf probe: Fix to get the DW_AT_decl_file and DW_AT_call_file as unsinged data")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>perf test: Fix "all PMU test" to skip parametrized events</title>
<updated>2022-12-31T12:26:50+00:00</updated>
<author>
<name>Michael Petlan</name>
<email>mpetlan@redhat.com</email>
</author>
<published>2022-12-19T16:30:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b783e03a7fb6de4ae012b74fca9f25d5e94d0703'/>
<id>urn:sha1:b783e03a7fb6de4ae012b74fca9f25d5e94d0703</id>
<content type='text'>
[ Upstream commit b50d691e50e600fab82b423be871860537d75dc9 ]

Parametrized events are not only a powerpc domain. They occur on other
platforms too (e.g. aarch64). They should be ignored in this testcase,
since proper setup of the parameters is out of scope of this script.

Let's not filter them out by PMU name, but rather based on the fact that
they expect a parameter.

Fixes: 451ed8058c69a3fe ("perf test: Fix "all PMU test" to skip hv_24x7/hv_gpci tests on powerpc")
Signed-off-by: Michael Petlan &lt;mpetlan@redhat.com&gt;
Cc: Athira Rajeev &lt;atrajeev@linux.vnet.ibm.com&gt;
Cc: Disha Goel &lt;disgoel@linux.vnet.ibm.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Nageswara R Sastry &lt;rnsastry@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20221219163008.9691-1-mpetlan@redhat.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 debug: Set debug_peo_args and redirect_to_stderr variable to correct values in perf_quiet_option()</title>
<updated>2022-12-31T12:26:50+00:00</updated>
<author>
<name>Yang Jihong</name>
<email>yangjihong1@huawei.com</email>
</author>
<published>2022-12-20T03:57:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5f2f72b7b5aca5801c3b4d0caf878786fbf69a37'/>
<id>urn:sha1:5f2f72b7b5aca5801c3b4d0caf878786fbf69a37</id>
<content type='text'>
[ Upstream commit 188ac720d364035008a54d249cf47b4cc100f819 ]

When perf uses quiet mode, perf_quiet_option() sets the 'debug_peo_args'
variable to -1, and display_attr() incorrectly determines the value of
'debug_peo_args'.  As a result, unexpected information is displayed.

Before:

  # perf record --quiet -- ls &gt; /dev/null
  ------------------------------------------------------------
  perf_event_attr:
    size                             128
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|PERIOD
    read_format                      ID|LOST
    disabled                         1
    inherit                          1
    mmap                             1
    comm                             1
    freq                             1
    enable_on_exec                   1
    task                             1
    precise_ip                       3
    sample_id_all                    1
    exclude_guest                    1
    mmap2                            1
    comm_exec                        1
    ksymbol                          1
    bpf_event                        1
  ------------------------------------------------------------
  ...

After:
  # perf record --quiet -- ls &gt; /dev/null
  #

redirect_to_stderr is a similar problem.

Fixes: f78eaef0e0493f60 ("perf tools: Allow to force redirect pr_debug to stderr.")
Fixes: ccd26741f5e6bdf2 ("perf tool: Provide an option to print perf_event_open args and return value")
Suggested-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Reviewed-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Signed-off-by: Yang Jihong &lt;yangjihong1@huawei.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Carsten Haitzler &lt;carsten.haitzler@arm.com&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: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: martin.lau@kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20221220035702.188413-2-yangjihong1@huawei.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: Do not delay the workload with --delay</title>
<updated>2022-12-31T12:26:31+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2022-12-12T23:08:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3599705789c7e4913c3a7eca8ba48636261901a9'/>
<id>urn:sha1:3599705789c7e4913c3a7eca8ba48636261901a9</id>
<content type='text'>
[ Upstream commit c587e77e100fa40eb6af10e00497c67acf493f33 ]

The -D/--delay option is to delay the measure after the program starts.
But the current code goes to sleep before starting the program so the
program is delayed too.  This is not the intention, let's fix it.

Before:

  $ time sudo ./perf stat -a -e cycles -D 3000 sleep 4
  Events disabled
  Events enabled

   Performance counter stats for 'system wide':

       4,326,949,337      cycles

         4.007494118 seconds time elapsed

  real	0m7.474s
  user	0m0.356s
  sys	0m0.120s

It ran the workload for 4 seconds and gave the 3 second delay.  So it
should skip the first 3 second and measure the last 1 second only.  But
as you can see, it delays 3 seconds and ran the workload after that for
4 seconds.  So the total time (real) was 7 seconds.

After:

  $ time sudo ./perf stat -a -e cycles -D 3000 sleep 4
  Events disabled
  Events enabled

   Performance counter stats for 'system wide':

       1,063,551,013      cycles

         1.002769510 seconds time elapsed

  real	0m4.484s
  user	0m0.385s
  sys	0m0.086s

The bug was introduced when it changed enablement of system-wide events
with a command line workload.  But it should've considered the initial
delay case.  The code was reworked since then (in bb8bc52e7578) so I'm
afraid it won't be applied cleanly.

Fixes: d0a0a511493d2695 ("perf stat: Fix forked applications enablement of counters")
Reported-by: Kevin Nomura &lt;nomurak@google.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Tested-by: Thomas Richter &lt;tmricht@linux.ibm.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&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;
Cc: Sumanth Korikkar &lt;sumanthk@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20221212230820.901382-1-namhyung@kernel.org
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 off_cpu: Fix a typo in BTF tracepoint name, it should be 'btf_trace_sched_switch'</title>
<updated>2022-12-31T12:26:31+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2022-12-08T18:26:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a4abe5e2e7b804e9d972121e547cc9c4ff0e2894'/>
<id>urn:sha1:a4abe5e2e7b804e9d972121e547cc9c4ff0e2894</id>
<content type='text'>
[ Upstream commit 167b266bf66c5b93171011ef9d1f09b070c2c537 ]

In BTF, tracepoint definitions have the "btf_trace_" prefix.  The
off-cpu profiler needs to check the signature of the sched_switch event
using that definition.  But there's a typo (s/bpf/btf/) so it failed
always.

Fixes: b36888f71c8542cd ("perf record: Handle argument change in sched_switch")
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: bpf@vger.kernel.org
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: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Song Liu &lt;song@kernel.org&gt;
Link: https://lore.kernel.org/r/20221208182636.524139-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
