tree f098555cb580b2864f145aa845b574f07d2cf694
parent 1f5a4ad97a0e7b663d527ecc02aabe203d000d91
author Roland McGrath <roland@redhat.com> 1217040358 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1217098809 -0700

tracehook: wait_task_inactive

This extends wait_task_inactive() with a new argument so it can be used in
a "soft" mode where it will check for the task changing state unexpectedly
and back off.  There is no change to existing callers.  This lays the
groundwork to allow robust, noninvasive tracing that can try to sample a
blocked thread but back off safely if it wakes up.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>