From: William Lee Irwin III <wli@holomorphy.com>

The patch (from Ingo) below is quite interesting, it allows the use of
readprofile not for statistical tine sampling, but for seeing where calls to
schedule() come from, so it can give some insight to the "where do my context
switches come from" question.

Boot with `profile=schedul2' to activate this feature.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>