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Kan Liang 39d5f412da perf evsel: Fixes topdown events in a weak group for the hybrid platform
The patch ("perf evlist: Keep topdown counters in weak group") fixes the
perf metrics topdown event issue when the topdown events are in a weak
group on a non-hybrid platform. However, it doesn't work for the hybrid
platform.

  $./perf stat -e '{cpu_core/slots/,cpu_core/topdown-bad-spec/,
  cpu_core/topdown-be-bound/,cpu_core/topdown-fe-bound/,
  cpu_core/topdown-retiring/,cpu_core/branch-instructions/,
  cpu_core/branch-misses/,cpu_core/bus-cycles/,cpu_core/cache-misses/,
  cpu_core/cache-references/,cpu_core/cpu-cycles/,cpu_core/instructions/,
  cpu_core/mem-loads/,cpu_core/mem-stores/,cpu_core/ref-cycles/,
  cpu_core/cache-misses/,cpu_core/cache-references/}:W' -a sleep 1

  Performance counter stats for 'system wide':

       751,765,068      cpu_core/slots/                        (84.07%)
   <not supported>      cpu_core/topdown-bad-spec/
   <not supported>      cpu_core/topdown-be-bound/
   <not supported>      cpu_core/topdown-fe-bound/
   <not supported>      cpu_core/topdown-retiring/
        12,398,197      cpu_core/branch-instructions/          (84.07%)
         1,054,218      cpu_core/branch-misses/                (84.24%)
       539,764,637      cpu_core/bus-cycles/                   (84.64%)
            14,683      cpu_core/cache-misses/                 (84.87%)
         7,277,809      cpu_core/cache-references/             (77.30%)
       222,299,439      cpu_core/cpu-cycles/                   (77.28%)
        63,661,714      cpu_core/instructions/                 (84.85%)
                 0      cpu_core/mem-loads/                    (77.29%)
        12,271,725      cpu_core/mem-stores/                   (77.30%)
       542,241,102      cpu_core/ref-cycles/                   (84.85%)
             8,854      cpu_core/cache-misses/                 (76.71%)
         7,179,013      cpu_core/cache-references/             (76.31%)

         1.003245250 seconds time elapsed

A hybrid platform has a different PMU name for the core PMUs, while
the current perf hard code the PMU name "cpu".

The evsel->pmu_name can be used to replace the "cpu" to fix the issue.
For a hybrid platform, the pmu_name must be non-NULL. Because there are
at least two core PMUs. The PMU has to be specified.
For a non-hybrid platform, the pmu_name may be NULL. Because there is
only one core PMU, "cpu". For a NULL pmu_name, we can safely assume that
it is a "cpu" PMU.

In case other PMUs also define the "slots" event, checking the PMU type
as well.

With the patch,

  $ perf stat -e '{cpu_core/slots/,cpu_core/topdown-bad-spec/,
  cpu_core/topdown-be-bound/,cpu_core/topdown-fe-bound/,
  cpu_core/topdown-retiring/,cpu_core/branch-instructions/,
  cpu_core/branch-misses/,cpu_core/bus-cycles/,cpu_core/cache-misses/,
  cpu_core/cache-references/,cpu_core/cpu-cycles/,cpu_core/instructions/,
  cpu_core/mem-loads/,cpu_core/mem-stores/,cpu_core/ref-cycles/,
  cpu_core/cache-misses/,cpu_core/cache-references/}:W' -a sleep 1

  Performance counter stats for 'system wide':

     766,620,266   cpu_core/slots/                                        (84.06%)
      73,172,129   cpu_core/topdown-bad-spec/ #    9.5% bad speculation   (84.06%)
     193,443,341   cpu_core/topdown-be-bound/ #    25.0% backend bound    (84.06%)
     403,940,929   cpu_core/topdown-fe-bound/ #    52.3% frontend bound   (84.06%)
     102,070,237   cpu_core/topdown-retiring/ #    13.2% retiring         (84.06%)
      12,364,429   cpu_core/branch-instructions/                          (84.03%)
       1,080,124   cpu_core/branch-misses/                                (84.24%)
     564,120,383   cpu_core/bus-cycles/                                   (84.65%)
          36,979   cpu_core/cache-misses/                                 (84.86%)
       7,298,094   cpu_core/cache-references/                             (77.30%)
     227,174,372   cpu_core/cpu-cycles/                                   (77.31%)
      63,886,523   cpu_core/instructions/                                 (84.87%)
               0   cpu_core/mem-loads/                                    (77.31%)
      12,208,782   cpu_core/mem-stores/                                   (77.31%)
     566,409,738   cpu_core/ref-cycles/                                   (84.87%)
          23,118   cpu_core/cache-misses/                                 (76.71%)
       7,212,602   cpu_core/cache-references/                             (76.29%)

       1.003228667 seconds time elapsed

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20220518143900.1493980-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-05-20 11:09:41 -03:00
arch powerpc fixes for 5.18 #5 2022-05-15 06:46:03 -07:00
block Revert "block: release rq qos structures for queue without disk" 2022-05-02 10:06:40 -06:00
certs Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
crypto for-5.18/64bit-pi-2022-03-25 2022-03-26 12:01:35 -07:00
Documentation Driver core fixes for 5.18-rc7 2022-05-15 08:08:51 -07:00
drivers Driver core fixes for 5.18-rc7 2022-05-15 08:08:51 -07:00
fs gfs2 fixes 2022-05-13 14:32:53 -07:00
include The recent expansion of the sched switch tracepoint inserted a new argument 2022-05-15 06:40:11 -07:00
init Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
ipc fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
kernel The recent expansion of the sched switch tracepoint inserted a new argument 2022-05-15 06:40:11 -07:00
lib dim: initialize all struct fields 2022-05-09 17:20:37 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm hotfixes for 5.18-rc7 2022-05-13 10:22:37 -07:00
net NFS client bugfixes for Linux 5.18 2022-05-13 11:04:37 -07:00
samples sched/tracing: Append prev_state to tp args instead 2022-05-12 00:37:11 +02:00
scripts objtool: Enable unreachable warnings for CLANG LTO 2022-04-19 21:58:48 +02:00
security hardening updates for v5.18-rc1-fix1 2022-03-31 11:43:01 -07:00
sound ASoC: Fixes for v5.18 2022-05-08 10:49:25 +02:00
tools perf evsel: Fixes topdown events in a weak group for the hybrid platform 2022-05-20 11:09:41 -03:00
usr Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
virt Merge branch 'kvm-fixes-for-5.18-rc5' into HEAD 2022-04-29 12:39:34 -04:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap hotfixes for 5.18-rc7 2022-05-13 10:22:37 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS perf tools fixes for v5.18: 5th batch 2022-05-14 11:43:47 -07:00
Makefile Linux 5.18-rc7 2022-05-15 18:08:58 -07:00
README

Linux kernel
============

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