locking, sched: Give waitqueue spinlocks their own lockdep classes
commit2fc391112fb6f3424435a3aa2fda887497b5f807
authorPeter Zijlstra <peterz@infradead.org>
Mon, 10 Aug 2009 11:33:05 +0000 (10 12:33 +0100)
committerIngo Molnar <mingo@elte.hu>
Mon, 10 Aug 2009 12:43:09 +0000 (10 14:43 +0200)
tree89cda7002d591807536dca68b6344a558b081428
parentbeda2c7ea2c15ed01eef00a997d2b0496c3a502d
locking, sched: Give waitqueue spinlocks their own lockdep classes

Give waitqueue spinlocks their own lockdep classes when they
are initialised from init_waitqueue_head().  This means that
struct wait_queue::func functions can operate other waitqueues.

This is used by CacheFiles to catch the page from a backing fs
being unlocked and to wake up another thread to take a copy of
it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Takashi Iwai <tiwai@suse.de>
Cc: linux-cachefs@redhat.com
Cc: torvalds@osdl.org
Cc: akpm@linux-foundation.org
LKML-Reference: <20090810113305.17284.81508.stgit@warthog.procyon.org.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
include/linux/wait.h
kernel/wait.c