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 <adrian.hunter@intel.com>
Tested-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1383313899-15987-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 4d644fe..7c8020a 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -888,6 +888,8 @@
"sample by weight (on special events only)"),
OPT_BOOLEAN(0, "transaction", &record.opts.sample_transaction,
"sample transaction flags (special events only)"),
+ OPT_BOOLEAN(0, "force-per-cpu", &record.opts.target.force_per_cpu,
+ "force the use of per-cpu mmaps"),
OPT_END()
};