linux/tools/perf/Documentation
Adrian Hunter 16b4b4e1a0 perf record: Respect --no-switch-events
Context switch events are added automatically by Intel PT and Coresight.

Make it possible to suppress them. That is useful for tracing the
scheduler without the disturbance that the switch event processing
creates.

Example:

  Prerequisites:

    $ which perf
    ~/bin/perf
    $ sudo setcap "cap_sys_rawio,cap_sys_admin,cap_sys_ptrace,cap_syslog,cap_ipc_lock=ep" ~/bin/perf
    $ sudo chmod +r /proc/kcore

  Before:

    $ perf record --no-switch-events --kcore -a -e intel_pt//k -- sleep 0.001
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.938 MB perf.data ]
    $ perf script -D | grep PERF_RECORD_SWITCH | wc -l
    572

  After:

    $ perf record --no-switch-events --kcore -a -e intel_pt//k -- sleep 0.001
    Warning:
    Intel Processor Trace decoding will not be possible except for kernel tracing!
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.838 MB perf.data ]
    $ perf script -D | grep PERF_RECORD_SWITCH | wc -l
    0

    $ sudo chmod go-r /proc/kcore
    $ sudo setcap -r ~/bin/perf

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: http://lore.kernel.org/lkml/20200528120859.21604-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 11:33:36 -03:00
..
android.txt
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 intel-pt: Update documentation about itrace G and L options 2020-05-05 16:35:30 -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 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 config: Add stat.big-num support 2020-05-28 10:03:27 -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-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 docs: Extend CAP_SYS_ADMIN with CAP_PERFMON where needed 2020-05-28 10:03:26 -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-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: Respect --no-switch-events 2020-05-28 11:33:36 -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 to enable the LBR stitching approach 2020-04-18 09:05:01 -03:00
perf-stat.txt perf metricgroup: Add options to not group or merge 2020-05-28 10:03:28 -03:00
perf-test.txt
perf-timechart.txt
perf-top.txt perf top: Add option to enable the LBR stitching approach 2020-04-18 09:05:01 -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
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