summaryrefslogtreecommitdiff
path: root/lib/dec_and_lock.c
diff options
context:
space:
mode:
authorDmitry Torokhov <dmitry.torokhov@gmail.com>2023-05-01 15:20:08 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2023-05-01 15:20:08 -0700
commit9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e (patch)
treed57f3a63479a07b4e0cece029886e76e04feb984 /lib/dec_and_lock.c
parent5dc63e56a9cf8df0b59c234a505a1653f1bdf885 (diff)
parent53bea86b5712c7491bb3dae12e271666df0a308c (diff)
Merge branch 'next' into for-linus
Prepare input updates for 6.4 merge window.
Diffstat (limited to 'lib/dec_and_lock.c')
-rw-r--r--lib/dec_and_lock.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/lib/dec_and_lock.c b/lib/dec_and_lock.c
index 9555b68bb774c..1dcca8f2e1942 100644
--- a/lib/dec_and_lock.c
+++ b/lib/dec_and_lock.c
@@ -49,3 +49,34 @@ int _atomic_dec_and_lock_irqsave(atomic_t *atomic, spinlock_t *lock,
return 0;
}
EXPORT_SYMBOL(_atomic_dec_and_lock_irqsave);
+
+int _atomic_dec_and_raw_lock(atomic_t *atomic, raw_spinlock_t *lock)
+{
+ /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
+ if (atomic_add_unless(atomic, -1, 1))
+ return 0;
+
+ /* Otherwise do it the slow way */
+ raw_spin_lock(lock);
+ if (atomic_dec_and_test(atomic))
+ return 1;
+ raw_spin_unlock(lock);
+ return 0;
+}
+EXPORT_SYMBOL(_atomic_dec_and_raw_lock);
+
+int _atomic_dec_and_raw_lock_irqsave(atomic_t *atomic, raw_spinlock_t *lock,
+ unsigned long *flags)
+{
+ /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
+ if (atomic_add_unless(atomic, -1, 1))
+ return 0;
+
+ /* Otherwise do it the slow way */
+ raw_spin_lock_irqsave(lock, *flags);
+ if (atomic_dec_and_test(atomic))
+ return 1;
+ raw_spin_unlock_irqrestore(lock, *flags);
+ return 0;
+}
+EXPORT_SYMBOL(_atomic_dec_and_raw_lock_irqsave);