diff options
author | Jonathan Corbet <corbet@lwn.net> | 2018-07-02 11:14:50 -0600 |
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committer | Jonathan Corbet <corbet@lwn.net> | 2018-07-02 11:14:50 -0600 |
commit | 5f6654094ff35a7a92eb76667788ef633595e4ea (patch) | |
tree | 8404c5fb245cddbc6877b97a9bf53139c95da852 /lib/refcount.c | |
parent | 5105730fbf6789ff9e20837bdefe32e8ba133595 (diff) | |
parent | 021c91791a5e7e85c567452f1be3e4c2c6cb6063 (diff) |
Merge tag 'v4.18-rc3' into docs-next
-rc1 broke the docs build due to changes in the e100/e1000 drivers; -rc3
got the fixes via the networking tree. Pull in -rc3 so that the docs tree
can actually build the docs again.
Diffstat (limited to 'lib/refcount.c')
-rw-r--r-- | lib/refcount.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/refcount.c b/lib/refcount.c index 0eb48353abe3..d3b81cefce91 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); |