perf evlist: Round mmap pages to power 2 - v2
authorDavid Ahern <dsahern@gmail.com>
Tue, 12 Nov 2013 14:46:54 +0000 (07:46 -0700)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Tue, 12 Nov 2013 19:31:53 +0000 (16:31 -0300)
commit9639837e95db90d056f4683c911717921519320e
tree98eb5457302a6bf58155c5de0fe76b3987314faf
parent8973504be70b2986a2081eeff7d9a4210dec295d
perf evlist: Round mmap pages to power 2 - v2

Currently perf requires the -m / --mmap_pages option to be a power of 2.

To be more user friendly perf should automatically round this up to the
next power of 2.

Currently:
  $ perf record -m 3 -a -- sleep 1
  --mmap_pages/-m value must be a power of two.sleep: Terminated

With patch:
  $ perf record -m 3 -a -- sleep 1
  rounding mmap pages size to 16384 (4 pages)
  ...

v2: Add bytes units to rounding message per Ingo's request. Other
    suggestions (e.g., prefixing INFO) should be addressed by wrapping
    pr_info to catch all instances.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1384267617-3446-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/evlist.c