From 043da846c2b2dfd5b187bf3a9993b8fb0a6ed94a Mon Sep 17 00:00:00 2001 From: Leo Yan Date: Mon, 12 Aug 2024 10:34:59 +0100 Subject: [PATCH] perf docs: Refine the description for the buffer size Current description for the AUX trace buffer size is misleading. When a user specifies the option '-m,512M', it represents a size value in bytes (512MiB) but not 512M pages (512M x 4KiB regard to a page of 4KiB). Make the document clear that the normal buffer and the AUX tracing buffer share the same semantics. Syncs the documents for consistent text. Reviewed-by: James Clark Signed-off-by: Leo Yan Cc: Adrian Hunter Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240812093459.2575278-1-leo.yan@arm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-kvm.txt | 6 +++--- tools/perf/Documentation/perf-record.txt | 9 +++++---- tools/perf/Documentation/perf-top.txt | 4 ++-- tools/perf/Documentation/perf-trace.txt | 4 ++-- 4 files changed, 12 insertions(+), 11 deletions(-) diff --git a/tools/perf/Documentation/perf-kvm.txt b/tools/perf/Documentation/perf-kvm.txt index b66be66fe836..c26524d38f47 100644 --- a/tools/perf/Documentation/perf-kvm.txt +++ b/tools/perf/Documentation/perf-kvm.txt @@ -115,9 +115,9 @@ STAT LIVE OPTIONS -m:: --mmap-pages=:: - Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. + Number of mmap data pages (must be a power of two) or size + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. -a:: --all-cpus:: diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index 41e36b4dc765..242223240a08 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -273,10 +273,11 @@ OPTIONS -m:: --mmap-pages=:: Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. - Also, by adding a comma, the number of mmap pages for AUX - area tracing can be specified. + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. + By adding a comma, an additional parameter with the same + semantics used for the normal mmap areas can be specified for + AUX tracing area. -g:: Enables call-graph (stack chain/backtrace) recording for both diff --git a/tools/perf/Documentation/perf-top.txt b/tools/perf/Documentation/perf-top.txt index 667e5102075e..af3e4230c72f 100644 --- a/tools/perf/Documentation/perf-top.txt +++ b/tools/perf/Documentation/perf-top.txt @@ -83,8 +83,8 @@ Default is to monitor all CPUS. -m :: --mmap-pages=:: Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. -p :: --pid=:: diff --git a/tools/perf/Documentation/perf-trace.txt b/tools/perf/Documentation/perf-trace.txt index f0da8cf63e9a..6e0cc50bbc13 100644 --- a/tools/perf/Documentation/perf-trace.txt +++ b/tools/perf/Documentation/perf-trace.txt @@ -106,8 +106,8 @@ filter out the startup phase of the program, which is often very different. -m:: --mmap-pages=:: Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. -C:: --cpu:: -- 2.50.1