diff options
| author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-09-08 01:01:14 -0300 |
|---|---|---|
| committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-09-08 01:01:14 -0300 |
| commit | e5fd91f1ef340da553f7a79da9540c3db711c937 (patch) | |
| tree | b11842027dc6641da63f4bcc524f8678263304a3 /arch/tile/lib/spinlock_32.c | |
| parent | 2a9b0348e685a63d97486f6749622b61e9e3292f (diff) | |
Linux-libre 4.2-gnu
Diffstat (limited to 'arch/tile/lib/spinlock_32.c')
| -rw-r--r-- | arch/tile/lib/spinlock_32.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/tile/lib/spinlock_32.c b/arch/tile/lib/spinlock_32.c index b34f79aad..88c2a5336 100644 --- a/arch/tile/lib/spinlock_32.c +++ b/arch/tile/lib/spinlock_32.c @@ -65,8 +65,17 @@ EXPORT_SYMBOL(arch_spin_trylock); void arch_spin_unlock_wait(arch_spinlock_t *lock) { u32 iterations = 0; - while (arch_spin_is_locked(lock)) + int curr = READ_ONCE(lock->current_ticket); + int next = READ_ONCE(lock->next_ticket); + + /* Return immediately if unlocked. */ + if (next == curr) + return; + + /* Wait until the current locker has released the lock. */ + do { delay_backoff(iterations++); + } while (READ_ONCE(lock->current_ticket) == curr); } EXPORT_SYMBOL(arch_spin_unlock_wait); |