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authorTakashi Iwai <tiwai@suse.de>2013-05-29 06:52:16 -0400
committerTakashi Iwai <tiwai@suse.de>2013-05-29 06:52:16 -0400
commit8a90bb5116889e98008fbc8178fc2a77bb51df4a (patch)
tree210b6755c9ae2d0d66a79f8696469ab50b7621ad /include/linux/kref.h
parentd47333ddb234dbc661ab2a4fe019758bd33ba33b (diff)
parent1ab9ecc24819a8cf8ee982aaf6fb83298f094b0d (diff)
Merge tag 'asoc-v3.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v3.10 A series of driver specific updates, none particularly critical, plus one fix to the compressed API code to handle capture streams properly which is very safe for mainline as there's no current users.
Diffstat (limited to 'include/linux/kref.h')
-rw-r--r--include/linux/kref.h33
1 files changed, 33 insertions, 0 deletions
diff --git a/include/linux/kref.h b/include/linux/kref.h
index e15828fd71f1..484604d184be 100644
--- a/include/linux/kref.h
+++ b/include/linux/kref.h
@@ -19,6 +19,7 @@
19#include <linux/atomic.h> 19#include <linux/atomic.h>
20#include <linux/kernel.h> 20#include <linux/kernel.h>
21#include <linux/mutex.h> 21#include <linux/mutex.h>
22#include <linux/spinlock.h>
22 23
23struct kref { 24struct kref {
24 atomic_t refcount; 25 atomic_t refcount;
@@ -98,6 +99,38 @@ static inline int kref_put(struct kref *kref, void (*release)(struct kref *kref)
98 return kref_sub(kref, 1, release); 99 return kref_sub(kref, 1, release);
99} 100}
100 101
102/**
103 * kref_put_spinlock_irqsave - decrement refcount for object.
104 * @kref: object.
105 * @release: pointer to the function that will clean up the object when the
106 * last reference to the object is released.
107 * This pointer is required, and it is not acceptable to pass kfree
108 * in as this function.
109 * @lock: lock to take in release case
110 *
111 * Behaves identical to kref_put with one exception. If the reference count
112 * drops to zero, the lock will be taken atomically wrt dropping the reference
113 * count. The release function has to call spin_unlock() without _irqrestore.
114 */
115static inline int kref_put_spinlock_irqsave(struct kref *kref,
116 void (*release)(struct kref *kref),
117 spinlock_t *lock)
118{
119 unsigned long flags;
120
121 WARN_ON(release == NULL);
122 if (atomic_add_unless(&kref->refcount, -1, 1))
123 return 0;
124 spin_lock_irqsave(lock, flags);
125 if (atomic_dec_and_test(&kref->refcount)) {
126 release(kref);
127 local_irq_restore(flags);
128 return 1;
129 }
130 spin_unlock_irqrestore(lock, flags);
131 return 0;
132}
133
101static inline int kref_put_mutex(struct kref *kref, 134static inline int kref_put_mutex(struct kref *kref,
102 void (*release)(struct kref *kref), 135 void (*release)(struct kref *kref),
103 struct mutex *lock) 136 struct mutex *lock)