linux/tools/perf/Documentation
Namhyung Kim 0df14c1f1e perf lock contention: Reject more than 10ms delays for safety
Delaying kernel operations can be dangerous and the kernel may kill
(non-sleepable) BPF programs running for long in the future.

Limit the max delay to 10ms and update the document about it.

  $ sudo ./perf lock con -abl -J 100000us@cgroup_mutex true
  lock delay is too long: 100000us (> 10ms)

   Usage: perf lock contention [<options>]

      -J, --inject-delay <TIME@FUNC>
                            Inject delays to specific locks

Suggested-by: Alexei Starovoitov <ast@kernel.org>
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: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20250515181042.555189-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-05-31 08:45:24 -03:00
..
android.txt
arm-coresight.txt perf docs: Fix man page build wrt perf-arm-coresight.txt 2022-10-25 17:40:48 -03:00
asciidoc.conf
asciidoctor-extensions.rb
build-docdep.perl
build-xed.txt
Build.txt perf docs: Document cross compilation 2024-07-26 11:15:55 -07:00
callchain-overhead-calculation.txt perf report: Add latency and parallelism profiling documentation 2025-02-18 14:04:32 -08:00
cat-texi.perl
cpu-and-latency-overheads.txt perf report: Add latency and parallelism profiling documentation 2025-02-18 14:04:32 -08:00
db-export.txt
examples.txt
guest-files.txt
guestmount.txt
intel-bts.txt
intel-hybrid.txt perf tools: Fix up some comments and code to properly use the event_source bus 2025-02-19 13:23:43 -08:00
intel-pt.txt
itrace.txt perf arm-spe: Update --itrace help text 2024-10-29 16:10:17 -07:00
jit-interface.txt
jitdump-specification.txt
Makefile perf doc: Add support for KBUILD_BUILD_TIMESTAMP 2023-05-15 17:49:01 -03:00
manpage-1.72.xsl
manpage-base.xsl
manpage-bold-literal.xsl
manpage-normal.xsl
manpage-suppress-sp.xsl
perf-amd-ibs.txt perf amd ibs: Add Load Latency bits in raw dump 2025-04-29 22:30:46 -03:00
perf-annotate.txt perf annotate: Add --code-with-type option. 2025-03-13 00:19:51 -07:00
perf-archive.txt
perf-arm-spe.txt perf docs: arm_spe: Document new discard mode 2025-01-10 14:50:55 +00:00
perf-bench.txt perf bench sched pipe: Add -G/--cgroups option 2023-10-25 10:02:10 -07:00
perf-buildid-cache.txt
perf-buildid-list.txt
perf-c2c.txt perf mem/c2c amd: Add ldlat support 2025-04-29 22:30:46 -03:00
perf-check.txt perf tools: Remove dependency on libaudit 2025-01-10 10:59:42 -03:00
perf-config.txt perf intel-pt: Do not default to recording all switch events 2025-05-12 14:18:16 -03:00
perf-daemon.txt
perf-data.txt
perf-diff.txt perf tools: Make quiet mode consistent between tools 2022-10-27 16:37:26 -03:00
perf-dlfilter.txt perf dlfilter: Add al_cleanup() 2023-08-15 16:41:49 -03:00
perf-evlist.txt
perf-ftrace.txt perf ftrace profile: Add --graph-opts option 2025-01-08 17:20:42 -03:00
perf-help.txt
perf-inject.txt
perf-intel-pt.txt perf intel-pt: Add documentation for pause / resume 2024-12-18 16:24:32 -03:00
perf-iostat.txt
perf-kallsyms.txt
perf-kmem.txt
perf-kvm.txt perf docs: Refine the description for the buffer size 2024-08-12 13:59:22 -03:00
perf-kwork.txt perf docs: Fix typos 2024-05-28 22:52:28 -07:00
perf-list.txt perf parse-events: Add "cpu" term to set the CPU an event is recorded on 2025-05-12 14:23:19 -03:00
perf-lock.txt perf lock contention: Reject more than 10ms delays for safety 2025-05-31 08:45:24 -03:00
perf-mem.txt perf mem: Describe overhead calculation in brief 2025-05-28 14:41:10 -03:00
perf-probe.txt perf docs: Fix a typo in 'perf probe' man page: l20th -> 120th 2023-01-19 09:49:59 -03:00
perf-record.txt perf record --off-cpu: Add --off-cpu-thresh option 2025-05-05 21:51:54 -03:00
perf-report.txt perf report: Add 'tgid' sort key 2025-05-13 17:51:32 -03:00
perf-sched.txt perf sched timehist: Add pre-migration wait time option 2024-10-14 12:04:31 -07:00
perf-script-perl.txt perf tools docs: Use canonical ftrace path 2023-02-02 16:32:19 -03:00
perf-script-python.txt perf scripting python: Add function to get a config value 2024-09-24 11:47:03 -07:00
perf-script.txt perf script: Update brstack syntax documentation 2025-03-14 10:41:08 -07:00
perf-stat.txt perf stat: Add mean, min, max and last --tpebs-mode options 2025-04-25 12:31:36 -03:00
perf-test.txt perf test: Improve verbose documentation 2025-01-16 11:01:03 -08:00
perf-timechart.txt
perf-top.txt perf docs: Refine the description for the buffer size 2024-08-12 13:59:22 -03:00
perf-trace.txt perf trace: Support --summary-mode=cgroup 2025-05-13 18:20:46 -03:00
perf-version.txt
perf.data-directory-format.txt
perf.data-file-format.txt perf record: Add 8-byte aligned event type PERF_RECORD_COMPRESSED2 2025-05-16 17:31:40 -03:00
perf.txt perf doc: Add AMD IBS usage document 2024-06-20 16:51:55 -07:00
perfconfig.example
security.txt
tips.txt perf report: Add latency and parallelism profiling documentation 2025-02-18 14:04:32 -08:00
topdown.txt perf Document: Add TPEBS (Timed PEBS(Precise Event-Based Sampling)) to Documents 2024-08-13 15:25:33 -03:00