ALSA: sound/isa: convert nested spin_lock_irqsave to spin_lock
authorJulia Lawall <julia@diku.dk>
Sat, 18 Jul 2009 15:26:14 +0000 (17:26 +0200)
committerTakashi Iwai <tiwai@suse.de>
Sun, 19 Jul 2009 12:02:29 +0000 (14:02 +0200)
commitfcb2954b9621dfeaca92f6a11dac69cfdfaa6705
tree81a2d9a04985a30fa7a9afb8db9ffc0c834f2b78
parentcb65c8732a50f8a145d36dbdac026a1789ad1587
ALSA: sound/isa: convert nested spin_lock_irqsave to spin_lock

If spin_lock_irqsave is called twice in a row with the same second
argument, the interrupt state at the point of the second call overwrites
the value saved by the first call.  Indeed, the second call does not need
to save the interrupt state, so it is changed to a simple spin_lock.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression lock1,lock2;
expression flags;
@@

*spin_lock_irqsave(lock1,flags)
... when != flags
*spin_lock_irqsave(lock2,flags)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/isa/gus/gus_pcm.c