On Tue, 2011-04-19 at 13:06 -0700, Andrew Morton wrote: > On Fri, 01 Apr 2011 14:13:11 +0200 > Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote: > > > Provide the mutex_lock_nest_lock() annotation. > > why? > > Neither the changelog nor the code provide any documentation for this addition to > the lokdep API. --- Subject: lockdep, mutex: Provide mutex_lock_nest_lock From: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Date: Fri, 26 Nov 2010 15:39:00 +0100 In order to convert i_mmap_lock to a mutex we need a mutex equivalent to spin_lock_nest_lock(), thus provide the mutex_lock_nest_lock() annotation. As with spin_lock_nest_lock(), mutex_lock_nest_lock() allows annotation of the locking pattern where an outer lock serializes the acquisition order of nested locks. That is, if every time you lock multiple locks A, say A1 and A2 you first acquire N, the order of acquiring A1 and A2 is irrelevant. Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> --- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href