From 539e6bb71e350541105e67e3d6c31392d9da25ef Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 1 Nov 2013 15:51:34 +0200 Subject: perf record: Add an option to force per-cpu mmaps By default, when tasks are specified (i.e. -p, -t or -u options) per-thread mmaps are created. Add an option to override that and force per-cpu mmaps. Further comments by peterz: So this option allows -t/-p/-u to create one buffer per cpu and attach all the various thread/process/user tasks' their counters to that one buffer? As opposed to the current state where each such counter would have its own buffer. Signed-off-by: Adrian Hunter Tested-by: Sukadev Bhattiprolu Acked-by: Peter Zijlstra Cc: David Ahern Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1383313899-15987-7-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-record.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'tools/perf/Documentation') diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index 052f7c4dc00c..43b42c4f4a91 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -201,6 +201,12 @@ abort events and some memory events in precise mode on modern Intel CPUs. --transaction:: Record transaction flags for transaction related events. +--force-per-cpu:: +Force the use of per-cpu mmaps. By default, when tasks are specified (i.e. -p, +-t or -u options) per-thread mmaps are created. This option overrides that and +forces per-cpu mmaps. A side-effect of that is that inheritance is +automatically enabled. Add the -i option also to disable inheritance. + SEE ALSO -------- linkperf:perf-stat[1], linkperf:perf-list[1] -- cgit v1.2.3-73-gaa49b