linux/tools/perf/Documentation
Andi Kleen 0997a2662f perf tools: Add support for exclusive groups/events
Peter suggested that using the exclusive mode in perf could avoid some
problems with bad scheduling of groups. Exclusive is implemented in the
kernel, but wasn't exposed by the perf tool, so hard to use without
custom low level API users.

Add support for marking groups or events with :e for exclusive in the
perf tool.  The implementation is basically the same as the existing
pinned attribute.

Committer testing:

  # perf test "parse event"
   6: Parse event definition strings                                  : Ok
  # perf test -v "parse event" |& grep :u*e
  running test 56 'instructions:uep'
  running test 57 '{cycles,cache-misses,branch-misses}:e'
  #
  #
  # grep "model name" -m1 /proc/cpuinfo
  model name	: AMD Ryzen 9 3900X 12-Core Processor
  #
  # perf stat -a -e '{cycles,cache-misses,branch-misses}:e' sleep 1

   Performance counter stats for 'system wide':

       <not counted>      cycles                                                        (0.00%)
       <not counted>      cache-misses                                                  (0.00%)
       <not counted>      branch-misses                                                 (0.00%)

         1.001269893 seconds time elapsed

  Some events weren't counted. Try disabling the NMI watchdog:
  	echo 0 > /proc/sys/kernel/nmi_watchdog
  	perf stat ...
  	echo 1 > /proc/sys/kernel/nmi_watchdog
  # echo 0 > /proc/sys/kernel/nmi_watchdog
  # perf stat -a -e '{cycles,cache-misses,branch-misses}:e' sleep 1

   Performance counter stats for 'system wide':

       1,298,663,141      cycles
          30,962,215      cache-misses
           5,325,150      branch-misses

         1.001474934 seconds time elapsed

  #
  # The output for asking for precise events on AMD needs to improve, it
  # supposedly works only for system wide or per CPU
  #
  # perf stat -a -e '{cycles,cache-misses,branch-misses}:uep' sleep 1
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles).
  /bin/dmesg | grep -i perf may provide additional information.

  # perf stat -a -e '{cycles,cache-misses,branch-misses}:ue' sleep 1

   Performance counter stats for 'system wide':

         746,363,126      cycles
          16,881,611      cache-misses
           2,871,259      branch-misses

         1.001636066 seconds time elapsed

  #

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20201014144255.22699-1-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-10-14 12:24:28 -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 perf tools: Document --children option in more detail 2015-04-29 10:38:06 -03:00
db-export.txt perf db-export: Add brief documentation 2019-06-05 09:47:57 -03:00
examples.txt perf record: Remove -f/--force option 2013-07-08 17:37:25 -03:00
intel-bts.txt perf tools: Add Intel BTS support 2015-08-21 11:34:10 -03:00
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 itrace 'q' option for quicker, less detailed decoding 2020-08-06 08:24:03 -03:00
jit-interface.txt perf symbols: Add description of JIT interface 2012-08-13 14:55:02 -03:00
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 archive: Remove duplicated 'runs' in man page 2013-12-09 15:21:45 -03:00
perf-bench.txt perf bench: Add basic syscall benchmark 2020-07-28 08:50:48 -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 report: Accept fifos as input file 2011-12-23 17:01:03 -02:00
perf-c2c.txt perf c2c: Fix 'perf c2c record -e list' to show the default events used 2020-05-28 10:03:25 -03:00
perf-config.txt perf annotate: Allow configuring the 'disassembler_style' knob via 'perf config' 2020-09-04 16:07:23 -03:00
perf-data.txt perf data: Add support to store time of day in CTF data conversion 2020-08-06 09:43:37 -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: ftrace: Add filter support for option -F/--funcs 2020-09-04 16:11:16 -03:00
perf-help.txt
perf-inject.txt perf inject: Add --buildid-all option 2020-10-13 11:01:42 -03:00
perf-intel-pt.txt perf intel-pt: Document snapshot control command 2020-09-04 16:11:09 -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 tools: Add support for exclusive groups/events 2020-10-14 12:24:28 -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 'snapshot' control command 2020-09-04 14:38:15 -03:00
perf-report.txt perf report: Add option to enable the LBR stitching approach 2020-04-18 09:05:01 -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 option --show-text-poke-events 2020-07-10 08:31:45 -03:00
perf-stat.txt perf stat: Add --for-each-cgroup option 2020-09-28 09:07:08 -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 tools: Add optional support for libpfm4 2020-05-29 16:51:38 -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: Store clock references for -k/--clockid option 2020-08-06 09:35:06 -03:00
perf.txt perf docs: Improve help information in perf.txt 2020-09-17 16:03:31 -03:00
perfconfig.example perf config: Show default report configuration in example and docs 2016-09-01 09:44:13 -03:00
security.txt perf docs: Introduce security.txt file to document related issues 2020-05-28 10:03:26 -03:00
tips.txt perf tools: Fix typos / broken sentences 2019-07-02 16:08:16 -03:00
topdown.txt perf tools: Add documentation for topdown metrics 2020-09-17 15:48:31 -03:00