WSL2-Linux-Kernel/tools/perf/Documentation
Namhyung Kim f9a35cd8f0 perf intel-pt: Do not try to queue auxtrace data on pipe
[ Upstream commit aeb802f872 ]

When it processes AUXTRACE_INFO, it calls to auxtrace_queue_data() to
collect AUXTRACE data first.  That won't work with pipe since it needs
lseek() to read the scattered aux data.

  $ perf record -o- -e intel_pt// true | perf report -i- --itrace=i100
  # To display the perf.data header info, please use --header/--header-only options.
  #
  0x4118 [0xa0]: failed to process type: 70
  Error:
  failed to process sample

For the pipe mode, it can handle the aux data as it gets.  But there's
no guarantee it can get the aux data in time.  So the following warning
will be shown at the beginning:

  WARNING: Intel PT with pipe mode is not recommended.
           The output cannot relied upon.  In particular,
           time stamps and the order of events may be incorrect.

Fixes: dbd134322e ("perf intel-pt: Add support for decoding AUX area samples")
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20230131023350.1903992-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10 09:39:33 +01:00
..
Build.txt
Makefile perf doc: Reorganize ARTICLES variables. 2021-08-02 09:56:18 -03:00
android.txt
asciidoc.conf
asciidoctor-extensions.rb
build-docdep.perl perf doc: Fix doc.dep 2021-08-02 09:56:17 -03:00
build-xed.txt
callchain-overhead-calculation.txt
cat-texi.perl perf doc: Fix perfman.info build 2021-08-02 09:56:17 -03:00
db-export.txt
examples.txt perf tools: Replace lkml.org links with lore 2021-02-11 12:54:27 -03:00
intel-bts.txt
intel-hybrid.txt perf docs: Fix accidental em-dashes 2021-08-10 11:05:21 -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 Z itrace option for timeless decoding 2021-05-12 12:43:10 -03:00
jit-interface.txt
jitdump-specification.txt perf doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00
manpage-1.72.xsl
manpage-base.xsl
manpage-bold-literal.xsl
manpage-normal.xsl
manpage-suppress-sp.xsl
perf-annotate.txt perf annotate: Add itrace options support 2021-06-16 15:07:42 -03:00
perf-archive.txt
perf-bench.txt perf bench: Add basic syscall benchmark 2020-07-28 08:50:48 -03:00
perf-buildid-cache.txt perf tools: Fix various typos in comments 2021-03-23 17:13:43 -03:00
perf-buildid-list.txt
perf-c2c.txt perf doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00
perf-config.txt perf intel-pt: Add a config for max loops without consuming a packet 2021-07-07 11:40:56 -03:00
perf-daemon.txt perf daemon: Add examples to man page 2021-02-11 10:19:52 -03:00
perf-data.txt perf data: Add JSON export 2021-04-29 10:30:58 -03:00
perf-diff.txt perf diff: Support hot streams comparison 2020-10-14 13:34:48 -03:00
perf-dlfilter.txt perf dlfilter: Amend documentation wrt library dependencies 2021-08-11 09:34:31 -03:00
perf-evlist.txt perf tools: Fix documentation of verbose options 2021-03-06 16:54:26 -03:00
perf-ftrace.txt perf tools: Fix documentation of verbose options 2021-03-06 16:54:26 -03:00
perf-help.txt
perf-inject.txt perf inject: Add --vm-time-correlation option 2021-05-12 12:43:10 -03:00
perf-intel-pt.txt perf intel-pt: Do not try to queue auxtrace data on pipe 2023-03-10 09:39:33 +01:00
perf-iostat.txt perf docs: Fix accidental em-dashes 2021-08-10 11:05:21 -03:00
perf-kallsyms.txt perf tools: Fix documentation of verbose options 2021-03-06 16:54:26 -03:00
perf-kmem.txt
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 doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00
perf-mem.txt perf mem: Support data page size 2021-01-20 14:34:20 -03:00
perf-probe.txt perf probe: Add permission and sysctl notice to man page 2021-06-04 10:24:38 -03:00
perf-record.txt perf docs: Fix accidental em-dashes 2021-08-10 11:05:21 -03:00
perf-report.txt perf report: Add --skip-empty option to suppress 0 event stat 2021-04-29 10:30:59 -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 doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00
perf-script-python.txt perf doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00
perf-script.txt perf script: Fix --list-dlfilters documentation 2021-08-11 09:34:07 -03:00
perf-stat.txt perf doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00
perf-test.txt
perf-timechart.txt
perf-top.txt perf top: Add cgroup support for perf top (-G) 2021-06-24 15:33:35 -03:00
perf-trace.txt perf tools: Fix documentation of verbose options 2021-03-06 16:54:26 -03:00
perf-version.txt
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 HYBRID_CPU_PMU_CAPS feature 2021-05-17 10:58:10 -03:00
perf.txt perf docs: Add man pages to see also 2021-03-02 09:37:38 -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
topdown.txt perf doc: Fix typos all over the place 2021-09-27 09:32:28 -03:00