<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/perf/util/Build, branch v5.13.2</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>perf tools: Fix dynamic libbpf link</title>
<updated>2021-05-10T12:01:00+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2021-05-08T20:50:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ad1237c30d975535a669746496cbed136aa5a045'/>
<id>ad1237c30d975535a669746496cbed136aa5a045</id>
<content type='text'>
Justin reported broken build with LIBBPF_DYNAMIC=1.

When linking libbpf dynamically we need to use perf's
hashmap object, because it's not exported in libbpf.so
(only in libbpf.a).

Following build is now passing:

  $ make LIBBPF_DYNAMIC=1
    BUILD:   Doing 'make -j8' parallel build
    ...
  $ ldd perf | grep libbpf
        libbpf.so.0 =&gt; /lib64/libbpf.so.0 (0x00007fa7630db000)

Fixes: eee19501926d ("perf tools: Grab a copy of libbpf's hashmap")
Reported-by: Justin M. Forbes &lt;jforbes@redhat.com&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Michael Petlan &lt;mpetlan@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lore.kernel.org/lkml/20210508205020.617984-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Justin reported broken build with LIBBPF_DYNAMIC=1.

When linking libbpf dynamically we need to use perf's
hashmap object, because it's not exported in libbpf.so
(only in libbpf.a).

Following build is now passing:

  $ make LIBBPF_DYNAMIC=1
    BUILD:   Doing 'make -j8' parallel build
    ...
  $ ldd perf | grep libbpf
        libbpf.so.0 =&gt; /lib64/libbpf.so.0 (0x00007fa7630db000)

Fixes: eee19501926d ("perf tools: Grab a copy of libbpf's hashmap")
Reported-by: Justin M. Forbes &lt;jforbes@redhat.com&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Michael Petlan &lt;mpetlan@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lore.kernel.org/lkml/20210508205020.617984-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf record: Create two hybrid 'cycles' events by default</title>
<updated>2021-04-29T13:30:59+00:00</updated>
<author>
<name>Jin Yao</name>
<email>yao.jin@linux.intel.com</email>
</author>
<published>2021-04-27T07:01:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b53a0755d5c2d19b13db897d6faf4969e03e45ae'/>
<id>b53a0755d5c2d19b13db897d6faf4969e03e45ae</id>
<content type='text'>
When evlist is empty, for example no '-e' specified in perf record,
one default 'cycles' event is added to evlist.

While on hybrid platform, it needs to create two default 'cycles'
events. One is for cpu_core, the other is for cpu_atom.

This patch actually calls evsel__new_cycles() two times to create
two 'cycles' events.

  # ./perf record -vv -a -- sleep 1
  ...
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x400000000
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|CPU|PERIOD
    read_format                      ID
    disabled                         1
    inherit                          1
    freq                             1
    precise_ip                       3
    sample_id_all                    1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
  sys_perf_event_open: pid -1  cpu 1  group_fd -1  flags 0x8 = 6
  sys_perf_event_open: pid -1  cpu 2  group_fd -1  flags 0x8 = 7
  sys_perf_event_open: pid -1  cpu 3  group_fd -1  flags 0x8 = 9
  sys_perf_event_open: pid -1  cpu 4  group_fd -1  flags 0x8 = 10
  sys_perf_event_open: pid -1  cpu 5  group_fd -1  flags 0x8 = 11
  sys_perf_event_open: pid -1  cpu 6  group_fd -1  flags 0x8 = 12
  sys_perf_event_open: pid -1  cpu 7  group_fd -1  flags 0x8 = 13
  sys_perf_event_open: pid -1  cpu 8  group_fd -1  flags 0x8 = 14
  sys_perf_event_open: pid -1  cpu 9  group_fd -1  flags 0x8 = 15
  sys_perf_event_open: pid -1  cpu 10  group_fd -1  flags 0x8 = 16
  sys_perf_event_open: pid -1  cpu 11  group_fd -1  flags 0x8 = 17
  sys_perf_event_open: pid -1  cpu 12  group_fd -1  flags 0x8 = 18
  sys_perf_event_open: pid -1  cpu 13  group_fd -1  flags 0x8 = 19
  sys_perf_event_open: pid -1  cpu 14  group_fd -1  flags 0x8 = 20
  sys_perf_event_open: pid -1  cpu 15  group_fd -1  flags 0x8 = 21
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x800000000
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|CPU|PERIOD
    read_format                      ID
    disabled                         1
    inherit                          1
    freq                             1
    precise_ip                       3
    sample_id_all                    1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 16  group_fd -1  flags 0x8 = 22
  sys_perf_event_open: pid -1  cpu 17  group_fd -1  flags 0x8 = 23
  sys_perf_event_open: pid -1  cpu 18  group_fd -1  flags 0x8 = 24
  sys_perf_event_open: pid -1  cpu 19  group_fd -1  flags 0x8 = 25
  sys_perf_event_open: pid -1  cpu 20  group_fd -1  flags 0x8 = 26
  sys_perf_event_open: pid -1  cpu 21  group_fd -1  flags 0x8 = 27
  sys_perf_event_open: pid -1  cpu 22  group_fd -1  flags 0x8 = 28
  sys_perf_event_open: pid -1  cpu 23  group_fd -1  flags 0x8 = 29
  ------------------------------------------------------------

We have to create evlist-hybrid.c otherwise due to the symbol
dependency the perf test python would be failed.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210427070139.25256-14-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When evlist is empty, for example no '-e' specified in perf record,
one default 'cycles' event is added to evlist.

While on hybrid platform, it needs to create two default 'cycles'
events. One is for cpu_core, the other is for cpu_atom.

This patch actually calls evsel__new_cycles() two times to create
two 'cycles' events.

  # ./perf record -vv -a -- sleep 1
  ...
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x400000000
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|CPU|PERIOD
    read_format                      ID
    disabled                         1
    inherit                          1
    freq                             1
    precise_ip                       3
    sample_id_all                    1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
  sys_perf_event_open: pid -1  cpu 1  group_fd -1  flags 0x8 = 6
  sys_perf_event_open: pid -1  cpu 2  group_fd -1  flags 0x8 = 7
  sys_perf_event_open: pid -1  cpu 3  group_fd -1  flags 0x8 = 9
  sys_perf_event_open: pid -1  cpu 4  group_fd -1  flags 0x8 = 10
  sys_perf_event_open: pid -1  cpu 5  group_fd -1  flags 0x8 = 11
  sys_perf_event_open: pid -1  cpu 6  group_fd -1  flags 0x8 = 12
  sys_perf_event_open: pid -1  cpu 7  group_fd -1  flags 0x8 = 13
  sys_perf_event_open: pid -1  cpu 8  group_fd -1  flags 0x8 = 14
  sys_perf_event_open: pid -1  cpu 9  group_fd -1  flags 0x8 = 15
  sys_perf_event_open: pid -1  cpu 10  group_fd -1  flags 0x8 = 16
  sys_perf_event_open: pid -1  cpu 11  group_fd -1  flags 0x8 = 17
  sys_perf_event_open: pid -1  cpu 12  group_fd -1  flags 0x8 = 18
  sys_perf_event_open: pid -1  cpu 13  group_fd -1  flags 0x8 = 19
  sys_perf_event_open: pid -1  cpu 14  group_fd -1  flags 0x8 = 20
  sys_perf_event_open: pid -1  cpu 15  group_fd -1  flags 0x8 = 21
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x800000000
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|CPU|PERIOD
    read_format                      ID
    disabled                         1
    inherit                          1
    freq                             1
    precise_ip                       3
    sample_id_all                    1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 16  group_fd -1  flags 0x8 = 22
  sys_perf_event_open: pid -1  cpu 17  group_fd -1  flags 0x8 = 23
  sys_perf_event_open: pid -1  cpu 18  group_fd -1  flags 0x8 = 24
  sys_perf_event_open: pid -1  cpu 19  group_fd -1  flags 0x8 = 25
  sys_perf_event_open: pid -1  cpu 20  group_fd -1  flags 0x8 = 26
  sys_perf_event_open: pid -1  cpu 21  group_fd -1  flags 0x8 = 27
  sys_perf_event_open: pid -1  cpu 22  group_fd -1  flags 0x8 = 28
  sys_perf_event_open: pid -1  cpu 23  group_fd -1  flags 0x8 = 29
  ------------------------------------------------------------

We have to create evlist-hybrid.c otherwise due to the symbol
dependency the perf test python would be failed.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210427070139.25256-14-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf parse-events: Create two hybrid hardware events</title>
<updated>2021-04-29T13:30:59+00:00</updated>
<author>
<name>Jin Yao</name>
<email>yao.jin@linux.intel.com</email>
</author>
<published>2021-04-27T07:01:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9cbfa2f64c04d98ad2bbce93066e2e021d12a24b'/>
<id>9cbfa2f64c04d98ad2bbce93066e2e021d12a24b</id>
<content type='text'>
Current hardware events has special perf types PERF_TYPE_HARDWARE.
But it doesn't pass the PMU type in the user interface. For a hybrid
system, the perf kernel doesn't know which PMU the events belong to.

So now this type is extended to be PMU aware type. The PMU type ID
is stored at attr.config[63:32].

PMU type ID is retrieved from sysfs.

  root@lkp-adl-d01:/sys/devices/cpu_atom# cat type
  8

  root@lkp-adl-d01:/sys/devices/cpu_core# cat type
  4

When enabling a hybrid hardware event without specified pmu, such as,
'perf stat -e cycles -a', two events are created automatically. One
is for atom, the other is for core.

  # perf stat -e cycles -a -vv -- sleep 1
  Control descriptor is not initialized
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x400000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 3
  ------------------------------------------------------------
  ...
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x400000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 15  group_fd -1  flags 0x8 = 19
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x800000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 16  group_fd -1  flags 0x8 = 20
  ------------------------------------------------------------
  ...
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x800000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 23  group_fd -1  flags 0x8 = 27
  cycles: 0: 836272 1001525722 1001525722
  cycles: 1: 628564 1001580453 1001580453
  cycles: 2: 872693 1001605997 1001605997
  cycles: 3: 70417 1001641369 1001641369
  cycles: 4: 88593 1001726722 1001726722
  cycles: 5: 470495 1001752993 1001752993
  cycles: 6: 484733 1001840440 1001840440
  cycles: 7: 1272477 1001593105 1001593105
  cycles: 8: 209185 1001608616 1001608616
  cycles: 9: 204391 1001633962 1001633962
  cycles: 10: 264121 1001661745 1001661745
  cycles: 11: 826104 1001689904 1001689904
  cycles: 12: 89935 1001728861 1001728861
  cycles: 13: 70639 1001756757 1001756757
  cycles: 14: 185266 1001784810 1001784810
  cycles: 15: 171094 1001825466 1001825466
  cycles: 0: 129624 1001854843 1001854843
  cycles: 1: 122533 1001840421 1001840421
  cycles: 2: 90055 1001882506 1001882506
  cycles: 3: 139607 1001896463 1001896463
  cycles: 4: 141791 1001907838 1001907838
  cycles: 5: 530927 1001883880 1001883880
  cycles: 6: 143246 1001852529 1001852529
  cycles: 7: 667769 1001872626 1001872626
  cycles: 6744979 16026956922 16026956922
  cycles: 1965552 8014991106 8014991106

   Performance counter stats for 'system wide':

           6,744,979      cpu_core/cycles/
           1,965,552      cpu_atom/cycles/

         1.001882711 seconds time elapsed

0x4 in 0x400000000 indicates the cpu_core pmu.
0x8 in 0x800000000 indicates the cpu_atom pmu.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210427070139.25256-9-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Current hardware events has special perf types PERF_TYPE_HARDWARE.
But it doesn't pass the PMU type in the user interface. For a hybrid
system, the perf kernel doesn't know which PMU the events belong to.

So now this type is extended to be PMU aware type. The PMU type ID
is stored at attr.config[63:32].

PMU type ID is retrieved from sysfs.

  root@lkp-adl-d01:/sys/devices/cpu_atom# cat type
  8

  root@lkp-adl-d01:/sys/devices/cpu_core# cat type
  4

When enabling a hybrid hardware event without specified pmu, such as,
'perf stat -e cycles -a', two events are created automatically. One
is for atom, the other is for core.

  # perf stat -e cycles -a -vv -- sleep 1
  Control descriptor is not initialized
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x400000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 3
  ------------------------------------------------------------
  ...
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x400000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 15  group_fd -1  flags 0x8 = 19
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x800000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 16  group_fd -1  flags 0x8 = 20
  ------------------------------------------------------------
  ...
  ------------------------------------------------------------
  perf_event_attr:
    size                             120
    config                           0x800000000
    sample_type                      IDENTIFIER
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 23  group_fd -1  flags 0x8 = 27
  cycles: 0: 836272 1001525722 1001525722
  cycles: 1: 628564 1001580453 1001580453
  cycles: 2: 872693 1001605997 1001605997
  cycles: 3: 70417 1001641369 1001641369
  cycles: 4: 88593 1001726722 1001726722
  cycles: 5: 470495 1001752993 1001752993
  cycles: 6: 484733 1001840440 1001840440
  cycles: 7: 1272477 1001593105 1001593105
  cycles: 8: 209185 1001608616 1001608616
  cycles: 9: 204391 1001633962 1001633962
  cycles: 10: 264121 1001661745 1001661745
  cycles: 11: 826104 1001689904 1001689904
  cycles: 12: 89935 1001728861 1001728861
  cycles: 13: 70639 1001756757 1001756757
  cycles: 14: 185266 1001784810 1001784810
  cycles: 15: 171094 1001825466 1001825466
  cycles: 0: 129624 1001854843 1001854843
  cycles: 1: 122533 1001840421 1001840421
  cycles: 2: 90055 1001882506 1001882506
  cycles: 3: 139607 1001896463 1001896463
  cycles: 4: 141791 1001907838 1001907838
  cycles: 5: 530927 1001883880 1001883880
  cycles: 6: 143246 1001852529 1001852529
  cycles: 7: 667769 1001872626 1001872626
  cycles: 6744979 16026956922 16026956922
  cycles: 1965552 8014991106 8014991106

   Performance counter stats for 'system wide':

           6,744,979      cpu_core/cycles/
           1,965,552      cpu_atom/cycles/

         1.001882711 seconds time elapsed

0x4 in 0x400000000 indicates the cpu_core pmu.
0x8 in 0x800000000 indicates the cpu_atom pmu.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210427070139.25256-9-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf pmu: Save detected hybrid pmus to a global pmu list</title>
<updated>2021-04-29T13:30:59+00:00</updated>
<author>
<name>Jin Yao</name>
<email>yao.jin@linux.intel.com</email>
</author>
<published>2021-04-27T07:01:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=444624307c4e06d35de12df1cfe08a4964ac086f'/>
<id>444624307c4e06d35de12df1cfe08a4964ac086f</id>
<content type='text'>
We identify the cpu_core pmu and cpu_atom pmu by explicitly
checking following files:

For cpu_core, checks:
"/sys/bus/event_source/devices/cpu_core/cpus"

For cpu_atom, checks:
"/sys/bus/event_source/devices/cpu_atom/cpus"

If the 'cpus' file exists and it has data, the pmu exists.

But in order not to hardcode the "cpu_core" and "cpu_atom",
and make the code in a generic way.

So if the path "/sys/bus/event_source/devices/cpu_xxx/cpus" exists, the
hybrid pmu exists. All the detected hybrid pmus are linked to a global
list 'perf_pmu__hybrid_pmus' and then next we just need to iterate the
list to get all hybrid pmu by using perf_pmu__for_each_hybrid_pmu.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210427070139.25256-6-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We identify the cpu_core pmu and cpu_atom pmu by explicitly
checking following files:

For cpu_core, checks:
"/sys/bus/event_source/devices/cpu_core/cpus"

For cpu_atom, checks:
"/sys/bus/event_source/devices/cpu_atom/cpus"

If the 'cpus' file exists and it has data, the pmu exists.

But in order not to hardcode the "cpu_core" and "cpu_atom",
and make the code in a generic way.

So if the path "/sys/bus/event_source/devices/cpu_xxx/cpus" exists, the
hybrid pmu exists. All the detected hybrid pmus are linked to a global
list 'perf_pmu__hybrid_pmus' and then next we just need to iterate the
list to get all hybrid pmu by using perf_pmu__for_each_hybrid_pmu.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210427070139.25256-6-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf data: Add JSON export</title>
<updated>2021-04-29T13:30:58+00:00</updated>
<author>
<name>Nicholas Fraser</name>
<email>nfraser@codeweavers.com</email>
</author>
<published>2021-04-26T14:47:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d0713d4ca3e94827de77f8758e3e8045a0d85215'/>
<id>d0713d4ca3e94827de77f8758e3e8045a0d85215</id>
<content type='text'>
This adds a feature to export perf data to JSON.

The resolved symbols are exported into the JSON so that external tools
don't need to load the dsos themselves (or even have access to them at
all.) This makes it easy to load and analyze perf data with standalone
tools where direct perf or libbabeltrace integration is impractical.

The exporter uses a minimal inline JSON encoding without any external
dependencies. Currently it only outputs some headers and sample metadata
but it's easily extensible.

Use it like this:

  $ perf data convert --to-json out.json

Committer notes:

Fixup a __printf() bug that broke the build:

  util/data-convert-json.c:103:11: error: expected ‘)’ before numeric constant
    103 | __(printf, 5, 6)
        |           ^~
        |           )
  util/data-convert-json.c: In function ‘output_sample_callchain_entry’:
  util/data-convert-json.c:124:2: error: implicit declaration of function ‘output_json_key_format’; did you mean ‘output_json_format’? [-Werror=implicit-function-declaration]
    124 |  output_json_key_format(out, false, 5, "ip", "\"0x%" PRIx64 "\"", ip);
        |  ^~~~~~~~~~~~~~~~~~~~~~
        |  output_json_format

Also had to add this patch to fix errors reported by various versions of
clang:

  -       if (al &amp;&amp; al-&gt;sym &amp;&amp; al-&gt;sym-&gt;name &amp;&amp; strlen(al-&gt;sym-&gt;name) &gt; 0) {
  +       if (al &amp;&amp; al-&gt;sym &amp;&amp; al-&gt;sym-&gt;namelen) {

al-&gt;sym-&gt;name is a zero sized array, to avoid one extra alloc in the
symbol__new() constructor, sym-&gt;namelen carries its strlen.

Committer testing:

  $ ls -la out.json
  ls: cannot access 'out.json': No such file or directory
  $ perf record sleep 0.1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
  $ perf report --stats | grep -w SAMPLE
            SAMPLE events:          8
  $ perf data convert --to-json out.json
  [ perf data convert: Converted 'perf.data' into JSON data 'out.json' ]
  [ perf data convert: Converted and wrote 0.002 MB (8 samples) ]
  $ ls -la out.json
  -rw-rw-r--. 1 acme acme 2017 Apr 26 17:29 out.json
  $ cat out.json
  {
  	"linux-perf-json-version": 1,
  	"headers": {
  		"header-version": 1,
  		"captured-on": "2021-04-26T20:28:57Z",
  		"data-offset": 432,
  		"data-size": 1016,
  		"feat-offset": 1448,
  		"hostname": "five",
  		"os-release": "5.11.14-200.fc33.x86_64",
  		"arch": "x86_64",
  		"cpu-desc": "AMD Ryzen 9 3900X 12-Core Processor",
  		"cpuid": "AuthenticAMD,23,113,0",
  		"nrcpus-online": 24,
  		"nrcpus-avail": 24,
  		"perf-version": "5.12.gee134f3189bd",
  		"cmdline": [
  			"/home/acme/bin/perf",
  			"record",
  			"sleep",
  			"0.1"
  		]
  	},
  	"samples": [
  		{
  			"timestamp": 170517539043684,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa6268827"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539048443,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa661359d"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539051018,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa6311e18"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539053652,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0x7fdb77b4812b",
  					"symbol": "_dl_start",
  					"dso": "ld-2.32.so"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539055306,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa6269286"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539057590,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa62abd8b"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539067559,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0x7fdb77b5e9e9",
  					"symbol": "__GI___tunables_init",
  					"dso": "ld-2.32.so"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539282452,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0x7fdb779978d2",
  					"symbol": "getenv",
  					"dso": "libc-2.32.so"
  				}
  			]
  		}
  	]
  }
  $

Signed-off-by: Nicholas Fraser &lt;nfraser@codeweavers.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Changbin Du &lt;changbin.du@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&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@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Tan Xiaojun &lt;tanxiaojun@huawei.com&gt;
Cc: Ulrich Czekalla &lt;uczekalla@codeweavers.com&gt;
Link: http://lore.kernel.org/lkml/3884969f-804d-2f53-c648-e2b0bd85edff@codeweavers.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This adds a feature to export perf data to JSON.

The resolved symbols are exported into the JSON so that external tools
don't need to load the dsos themselves (or even have access to them at
all.) This makes it easy to load and analyze perf data with standalone
tools where direct perf or libbabeltrace integration is impractical.

The exporter uses a minimal inline JSON encoding without any external
dependencies. Currently it only outputs some headers and sample metadata
but it's easily extensible.

Use it like this:

  $ perf data convert --to-json out.json

Committer notes:

Fixup a __printf() bug that broke the build:

  util/data-convert-json.c:103:11: error: expected ‘)’ before numeric constant
    103 | __(printf, 5, 6)
        |           ^~
        |           )
  util/data-convert-json.c: In function ‘output_sample_callchain_entry’:
  util/data-convert-json.c:124:2: error: implicit declaration of function ‘output_json_key_format’; did you mean ‘output_json_format’? [-Werror=implicit-function-declaration]
    124 |  output_json_key_format(out, false, 5, "ip", "\"0x%" PRIx64 "\"", ip);
        |  ^~~~~~~~~~~~~~~~~~~~~~
        |  output_json_format

Also had to add this patch to fix errors reported by various versions of
clang:

  -       if (al &amp;&amp; al-&gt;sym &amp;&amp; al-&gt;sym-&gt;name &amp;&amp; strlen(al-&gt;sym-&gt;name) &gt; 0) {
  +       if (al &amp;&amp; al-&gt;sym &amp;&amp; al-&gt;sym-&gt;namelen) {

al-&gt;sym-&gt;name is a zero sized array, to avoid one extra alloc in the
symbol__new() constructor, sym-&gt;namelen carries its strlen.

Committer testing:

  $ ls -la out.json
  ls: cannot access 'out.json': No such file or directory
  $ perf record sleep 0.1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
  $ perf report --stats | grep -w SAMPLE
            SAMPLE events:          8
  $ perf data convert --to-json out.json
  [ perf data convert: Converted 'perf.data' into JSON data 'out.json' ]
  [ perf data convert: Converted and wrote 0.002 MB (8 samples) ]
  $ ls -la out.json
  -rw-rw-r--. 1 acme acme 2017 Apr 26 17:29 out.json
  $ cat out.json
  {
  	"linux-perf-json-version": 1,
  	"headers": {
  		"header-version": 1,
  		"captured-on": "2021-04-26T20:28:57Z",
  		"data-offset": 432,
  		"data-size": 1016,
  		"feat-offset": 1448,
  		"hostname": "five",
  		"os-release": "5.11.14-200.fc33.x86_64",
  		"arch": "x86_64",
  		"cpu-desc": "AMD Ryzen 9 3900X 12-Core Processor",
  		"cpuid": "AuthenticAMD,23,113,0",
  		"nrcpus-online": 24,
  		"nrcpus-avail": 24,
  		"perf-version": "5.12.gee134f3189bd",
  		"cmdline": [
  			"/home/acme/bin/perf",
  			"record",
  			"sleep",
  			"0.1"
  		]
  	},
  	"samples": [
  		{
  			"timestamp": 170517539043684,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa6268827"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539048443,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa661359d"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539051018,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa6311e18"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539053652,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0x7fdb77b4812b",
  					"symbol": "_dl_start",
  					"dso": "ld-2.32.so"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539055306,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa6269286"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539057590,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0xffffffffa62abd8b"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539067559,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0x7fdb77b5e9e9",
  					"symbol": "__GI___tunables_init",
  					"dso": "ld-2.32.so"
  				}
  			]
  		},
  		{
  			"timestamp": 170517539282452,
  			"pid": 375844,
  			"tid": 375844,
  			"comm": "sleep",
  			"callchain": [
  				{
  					"ip": "0x7fdb779978d2",
  					"symbol": "getenv",
  					"dso": "libc-2.32.so"
  				}
  			]
  		}
  	]
  }
  $

Signed-off-by: Nicholas Fraser &lt;nfraser@codeweavers.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Changbin Du &lt;changbin.du@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&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@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Tan Xiaojun &lt;tanxiaojun@huawei.com&gt;
Cc: Ulrich Czekalla &lt;uczekalla@codeweavers.com&gt;
Link: http://lore.kernel.org/lkml/3884969f-804d-2f53-c648-e2b0bd85edff@codeweavers.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf stat: Basic support for iostat in perf</title>
<updated>2021-04-20T11:40:20+00:00</updated>
<author>
<name>Alexander Antonov</name>
<email>alexander.antonov@linux.intel.com</email>
</author>
<published>2021-04-19T09:41:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f07952b17969777196512368a216baae1ad45ea6'/>
<id>f07952b17969777196512368a216baae1ad45ea6</id>
<content type='text'>
Add basic flow for a new iostat mode in perf. Mode is intended to
provide four I/O performance metrics per each PCIe root port: Inbound Read,
Inbound Write, Outbound Read, Outbound Write.

The actual code to compute the metrics and attribute it to
root port is in follow-on patches.

Signed-off-by: Alexander Antonov &lt;alexander.antonov@linux.intel.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Alexey V Bayduraev &lt;alexey.v.bayduraev@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210419094147.15909-2-alexander.antonov@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add basic flow for a new iostat mode in perf. Mode is intended to
provide four I/O performance metrics per each PCIe root port: Inbound Read,
Inbound Write, Outbound Read, Outbound Write.

The actual code to compute the metrics and attribute it to
root port is in follow-on patches.

Signed-off-by: Alexander Antonov &lt;alexander.antonov@linux.intel.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Alexey V Bayduraev &lt;alexey.v.bayduraev@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/20210419094147.15909-2-alexander.antonov@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Add OCaml demangling</title>
<updated>2021-02-17T18:15:06+00:00</updated>
<author>
<name>Fabian Hemmer</name>
<email>copy@copy.sh</email>
</author>
<published>2021-02-03T21:15:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cef7af25c9d3a7ea5d0c82424dc8bf93a95b6fc3'/>
<id>cef7af25c9d3a7ea5d0c82424dc8bf93a95b6fc3</id>
<content type='text'>
Detect symbols generated by the OCaml compiler based on their prefix.

Demangle OCaml symbols, returning a newly allocated string (like the
existing Java demangling functionality).

Move a helper function (hex) from tests/code-reading.c to util/string.c

To test:

  echo 'Printf.printf "%d\n" (Random.int 42)' &gt; test.ml
  perf record ocamlopt.opt test.ml
  perf report -d ocamlopt.opt

Signed-off-by: Fabian Hemmer &lt;copy@copy.sh&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
LPU-Reference: 20210203211537.b25ytjb6dq5jfbwx@nyu
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Detect symbols generated by the OCaml compiler based on their prefix.

Demangle OCaml symbols, returning a newly allocated string (like the
existing Java demangling functionality).

Move a helper function (hex) from tests/code-reading.c to util/string.c

To test:

  echo 'Printf.printf "%d\n" (Random.int 42)' &gt; test.ml
  perf record ocamlopt.opt test.ml
  perf report -d ocamlopt.opt

Signed-off-by: Fabian Hemmer &lt;copy@copy.sh&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
LPU-Reference: 20210203211537.b25ytjb6dq5jfbwx@nyu
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf stat: Enable counting events for BPF programs</title>
<updated>2021-01-20T17:25:28+00:00</updated>
<author>
<name>Song Liu</name>
<email>songliubraving@fb.com</email>
</author>
<published>2020-12-29T21:42:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa853c4b839ece9cd589e8858819240933cc4d78'/>
<id>fa853c4b839ece9cd589e8858819240933cc4d78</id>
<content type='text'>
Introduce 'perf stat -b' option, which counts events for BPF programs, like:

  [root@localhost ~]# ~/perf stat -e ref-cycles,cycles -b 254 -I 1000
     1.487903822            115,200      ref-cycles
     1.487903822             86,012      cycles
     2.489147029             80,560      ref-cycles
     2.489147029             73,784      cycles
     3.490341825             60,720      ref-cycles
     3.490341825             37,797      cycles
     4.491540887             37,120      ref-cycles
     4.491540887             31,963      cycles

The example above counts 'cycles' and 'ref-cycles' of BPF program of id
254.  This is similar to bpftool-prog-profile command, but more
flexible.

'perf stat -b' creates per-cpu perf_event and loads fentry/fexit BPF
programs (monitor-progs) to the target BPF program (target-prog). The
monitor-progs read perf_event before and after the target-prog, and
aggregate the difference in a BPF map. Then the user space reads data
from these maps.

A new 'struct bpf_counter' is introduced to provide a common interface
that uses BPF programs/maps to count perf events.

Committer notes:

Removed all but bpf_counter.h includes from evsel.h, not needed at all.

Also BPF map lookups for PERCPU_ARRAYs need to have as its value receive
buffer passed to the kernel libbpf_num_possible_cpus() entries, not
evsel__nr_cpus(evsel), as the former uses
/sys/devices/system/cpu/possible while the later uses
/sys/devices/system/cpu/online, which may be less than the 'possible'
number making the bpf map lookup overwrite memory and cause hard to
debug memory corruption.

We need to continue using evsel__nr_cpus(evsel) when accessing the
perf_counts array tho, not to overwrite another are of memory :-)

Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Link: https://lore.kernel.org/lkml/20210120163031.GU12699@kernel.org/
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: kernel-team@fb.com
Link: http://lore.kernel.org/lkml/20201229214214.3413833-4-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce 'perf stat -b' option, which counts events for BPF programs, like:

  [root@localhost ~]# ~/perf stat -e ref-cycles,cycles -b 254 -I 1000
     1.487903822            115,200      ref-cycles
     1.487903822             86,012      cycles
     2.489147029             80,560      ref-cycles
     2.489147029             73,784      cycles
     3.490341825             60,720      ref-cycles
     3.490341825             37,797      cycles
     4.491540887             37,120      ref-cycles
     4.491540887             31,963      cycles

The example above counts 'cycles' and 'ref-cycles' of BPF program of id
254.  This is similar to bpftool-prog-profile command, but more
flexible.

'perf stat -b' creates per-cpu perf_event and loads fentry/fexit BPF
programs (monitor-progs) to the target BPF program (target-prog). The
monitor-progs read perf_event before and after the target-prog, and
aggregate the difference in a BPF map. Then the user space reads data
from these maps.

A new 'struct bpf_counter' is introduced to provide a common interface
that uses BPF programs/maps to count perf events.

Committer notes:

Removed all but bpf_counter.h includes from evsel.h, not needed at all.

Also BPF map lookups for PERCPU_ARRAYs need to have as its value receive
buffer passed to the kernel libbpf_num_possible_cpus() entries, not
evsel__nr_cpus(evsel), as the former uses
/sys/devices/system/cpu/possible while the later uses
/sys/devices/system/cpu/online, which may be less than the 'possible'
number making the bpf map lookup overwrite memory and cause hard to
debug memory corruption.

We need to continue using evsel__nr_cpus(evsel) when accessing the
perf_counts array tho, not to overwrite another are of memory :-)

Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Link: https://lore.kernel.org/lkml/20210120163031.GU12699@kernel.org/
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: kernel-team@fb.com
Link: http://lore.kernel.org/lkml/20201229214214.3413833-4-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf streams: Introduce branch history "streams"</title>
<updated>2020-10-14T16:27:28+00:00</updated>
<author>
<name>Jin Yao</name>
<email>yao.jin@linux.intel.com</email>
</author>
<published>2020-10-09T02:28:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=480accbb17609be01abcd09517605a930791bfdb'/>
<id>480accbb17609be01abcd09517605a930791bfdb</id>
<content type='text'>
We define a stream as the branch history which is aggregated by the
branch records from perf samples. For example, the callchains aggregated
from the branch records are considered as streams.  By browsing the hot
stream, we can understand the hot code path.

Now we only support the callchain for stream. For measuring the hot
level for a stream, we use the callchain_node-&gt;hit, higher is hotter.

There may be many callchains sampled so we only focus on the top N
hottest callchains. N is a user defined parameter or predefined default
value (nr_streams_max).

This patch creates an evsel_streams array per event, and saves the top N
hottest streams in a stream array.

So now we can get the per-event top N hottest streams.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20201009022845.13141-2-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We define a stream as the branch history which is aggregated by the
branch records from perf samples. For example, the callchains aggregated
from the branch records are considered as streams.  By browsing the hot
stream, we can understand the hot code path.

Now we only support the callchain for stream. For measuring the hot
level for a stream, we use the callchain_node-&gt;hit, higher is hotter.

There may be many callchains sampled so we only focus on the top N
hottest callchains. N is a user defined parameter or predefined default
value (nr_streams_max).

This patch creates an evsel_streams array per event, and saves the top N
hottest streams in a stream array.

So now we can get the per-event top N hottest streams.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20201009022845.13141-2-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Rename group to topdown</title>
<updated>2020-09-17T18:47:55+00:00</updated>
<author>
<name>Kan Liang</name>
<email>kan.liang@linux.intel.com</email>
</author>
<published>2020-09-11T14:48:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=687986bbeb668068d39a47658edf4d7a6414eefb'/>
<id>687986bbeb668068d39a47658edf4d7a6414eefb</id>
<content type='text'>
The group.h/c only include TopDown group related functions. The name
"group" is too generic and inaccurate. Use the name "topdown" to replace
it.

Move topdown related functions to a dedicated file, topdown.c.

Signed-off-by: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lore.kernel.org/lkml/20200911144808.27603-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The group.h/c only include TopDown group related functions. The name
"group" is too generic and inaccurate. Use the name "topdown" to replace
it.

Move topdown related functions to a dedicated file, topdown.c.

Signed-off-by: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lore.kernel.org/lkml/20200911144808.27603-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
