linux_dsm_epyc7002/tools/perf/Documentation
Kan Liang 6f91ea283a perf header: Support CPU PMU capabilities
To stitch LBR call stack, the max LBR information is required. So the
CPU PMU capabilities information has to be stored in perf header.

Add a new feature HEADER_CPU_PMU_CAPS for CPU PMU capabilities.
Retrieve all CPU PMU capabilities, not just max LBR information.

Add variable max_branches to facilitate future usage.

Committer testing:

  # ls -la /sys/devices/cpu/caps/
  total 0
  drwxr-xr-x. 2 root root    0 Apr 17 10:53 .
  drwxr-xr-x. 6 root root    0 Apr 17 07:02 ..
  -r--r--r--. 1 root root 4096 Apr 17 10:53 max_precise
  #
  # cat /sys/devices/cpu/caps/max_precise
  0
  # perf record sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.033 MB perf.data (7 samples) ]
  #
  # perf report --header-only | egrep 'cpu(desc|.*capabilities)'
  # cpudesc : AMD Ryzen 5 3600X 6-Core Processor
  # cpu pmu capabilities: max_precise=0
  #

And then on an Intel machine:

  $ ls -la /sys/devices/cpu/caps/
  total 0
  drwxr-xr-x. 2 root root    0 Apr 17 10:51 .
  drwxr-xr-x. 6 root root    0 Apr 17 10:04 ..
  -r--r--r--. 1 root root 4096 Apr 17 11:37 branches
  -r--r--r--. 1 root root 4096 Apr 17 10:51 max_precise
  -r--r--r--. 1 root root 4096 Apr 17 11:37 pmu_name
  $ cat /sys/devices/cpu/caps/max_precise
  3
  $ cat /sys/devices/cpu/caps/branches
  32
  $ cat /sys/devices/cpu/caps/pmu_name
  skylake
  $ perf record sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
  $ perf report --header-only | egrep 'cpu(desc|.*capabilities)'
  # cpudesc : Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
  # cpu pmu capabilities: branches=32, max_precise=3, pmu_name=skylake
  $

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-3-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
..
android.txt perf tools: Update android build documentation 2016-07-04 20:27:27 -03:00
asciidoc.conf perf docs: Allow man page date to be specified 2019-09-27 09:26:14 -03:00
asciidoctor-extensions.rb perf Documentation: Support for asciidoctor 2018-04-26 13:47:10 -03:00
build-xed.txt perf script: Add --insn-trace for instruction decoding 2018-10-24 15:29:50 -03:00
Build.txt perf tools: Add doc about how to build perf with Asan and UBSan 2019-03-19 16:52:04 -03:00
callchain-overhead-calculation.txt
db-export.txt perf db-export: Add brief documentation 2019-06-05 09:47:57 -03:00
examples.txt
intel-bts.txt
intel-pt.txt perf intel-pt: Update intel-pt.txt file with new location of the documentation 2020-03-11 11:00:33 -03:00
itrace.txt perf auxtrace: Add an option to synthesize callchains for regular events 2020-04-16 12:19:15 -03:00
jit-interface.txt
jitdump-specification.txt perf docs: Correct and clarify jitdump spec 2019-09-30 17:29:51 -03:00
Makefile perf doc: allow ASCIIDOC_EXTRA to be an argument 2020-04-18 09:05:00 -03:00
manpage-1.72.xsl
manpage-base.xsl
manpage-bold-literal.xsl
manpage-normal.xsl
manpage-suppress-sp.xsl
perf-annotate.txt perf tools: Support --prefix/--prefix-strip 2020-01-14 12:02:19 -03:00
perf-archive.txt
perf-bench.txt perf bench: Add event synthesis benchmark 2020-04-16 12:19:12 -03:00
perf-buildid-cache.txt perf buildid-cache: Support --purge-all option 2018-04-26 09:30:26 -03:00
perf-buildid-list.txt
perf-c2c.txt perf mem/c2c: Fix perf_mem_events to support powerpc 2019-02-04 11:32:14 -03:00
perf-config.txt perf callchain: Update docs regarding kernel/user space unwinding 2020-03-25 16:13:21 -03:00
perf-data.txt perf tools: Correct title markers for asciidoctor 2018-03-07 10:26:32 -03:00
perf-diff.txt perf diff: Report noisy for cycles diff 2019-10-11 10:57:00 -03:00
perf-evlist.txt perf evlist: Document missing --force option 2017-11-16 14:50:07 -03:00
perf-ftrace.txt perf tools: Correct title markers for asciidoctor 2018-03-07 10:26:32 -03:00
perf-help.txt
perf-inject.txt perf intel-pt: Add Intel PT man page references 2020-03-11 11:00:09 -03:00
perf-intel-pt.txt perf intel-pt: Add Intel PT man page references 2020-03-11 11:00:09 -03:00
perf-kallsyms.txt perf tools: Correct title markers for asciidoctor 2018-03-07 10:26:32 -03:00
perf-kmem.txt perf kmem: Document a missing option & an argument 2018-02-16 14:55:42 -03:00
perf-kvm.txt perf kvm: Clarify the 'perf kvm' -i and -o command line options 2019-12-02 15:38:59 -03:00
perf-list.txt perf parser: Add support to specify rXXX event with pmu 2020-04-18 09:05:00 -03:00
perf-lock.txt perf lock: Document missing options 2017-11-16 14:50:04 -03:00
perf-mem.txt perf mem/c2c: Fix perf_mem_events to support powerpc 2019-02-04 11:32:14 -03:00
perf-probe.txt perf-probe: Add user memory access attribute support 2019-05-25 23:04:42 -04:00
perf-record.txt perf record: Add --all-cgroups option 2020-04-03 09:37:55 -03:00
perf-report.txt perf report: Add 'cgroup' sort key 2020-04-03 09:37:55 -03:00
perf-sched.txt perf sched timehist: Add support for filtering on CPU 2020-01-06 11:46:09 -03:00
perf-script-perl.txt perf tools: Correct title markers for asciidoctor 2018-03-07 10:26:32 -03:00
perf-script-python.txt perf script python: Add dict fields introduction to Documentation 2018-06-06 15:40:10 -03:00
perf-script.txt perf script: add -S/--symbols documentation 2020-04-03 09:37:56 -03:00
perf-stat.txt perf stat: Show percore counts in per CPU output 2020-03-04 10:34:09 -03:00
perf-test.txt perf test: Add -F/--dont-fork option 2016-06-30 18:27:45 -03:00
perf-timechart.txt perf timechart: Document missing --force option 2017-11-16 14:50:06 -03:00
perf-top.txt perf top: Support --group-sort-idx to change the sort order 2020-04-03 09:37:55 -03:00
perf-trace.txt perf trace: Introduce --errno-summary 2019-10-15 13:03:49 -03:00
perf-version.txt perf version: Add man page 2018-04-02 13:52:23 -03:00
perf.data-directory-format.txt perf record: Put a copy of kcore into the perf.data directory 2019-11-06 15:43:05 -03:00
perf.data-file-format.txt perf header: Support CPU PMU capabilities 2020-04-18 09:05:00 -03:00
perf.txt perf tool: Provide an option to print perf_event_open args and return value 2019-11-12 08:32:27 -03:00
perfconfig.example perf config: Show default report configuration in example and docs 2016-09-01 09:44:13 -03:00
tips.txt perf tools: Fix typos / broken sentences 2019-07-02 16:08:16 -03:00