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authorTakashi Iwai <tiwai@suse.de>2018-07-18 17:42:34 +0200
committerTakashi Iwai <tiwai@suse.de>2018-07-18 17:42:40 +0200
commit67ece13ffe862f9d17a144c6cd3feef88a57db13 (patch)
treeec2036681d19a9c10b2fad941eb8f58f9eafcfc8 /lib/refcount.c
parentfa84cf094ef9667e2b91c104b0a788fd1896f482 (diff)
parent4aaf448fa9754e2d5ee188d32327b24ffc15ca4d (diff)
Merge branch 'topic/vga_switcheroo' into for-next
Pull the vga_switcheroo audio client fix. Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'lib/refcount.c')
-rw-r--r--lib/refcount.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/refcount.c b/lib/refcount.c
index 0eb48353abe30..d3b81cefce91a 100644
--- a/lib/refcount.c
+++ b/lib/refcount.c
@@ -350,3 +350,31 @@ bool refcount_dec_and_lock(refcount_t *r, spinlock_t *lock)
}
EXPORT_SYMBOL(refcount_dec_and_lock);
+/**
+ * refcount_dec_and_lock_irqsave - return holding spinlock with disabled
+ * interrupts if able to decrement refcount to 0
+ * @r: the refcount
+ * @lock: the spinlock to be locked
+ * @flags: saved IRQ-flags if the is acquired
+ *
+ * Same as refcount_dec_and_lock() above except that the spinlock is acquired
+ * with disabled interupts.
+ *
+ * Return: true and hold spinlock if able to decrement refcount to 0, false
+ * otherwise
+ */
+bool refcount_dec_and_lock_irqsave(refcount_t *r, spinlock_t *lock,
+ unsigned long *flags)
+{
+ if (refcount_dec_not_one(r))
+ return false;
+
+ spin_lock_irqsave(lock, *flags);
+ if (!refcount_dec_and_test(r)) {
+ spin_unlock_irqrestore(lock, *flags);
+ return false;
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(refcount_dec_and_lock_irqsave);