diff options
| author |   José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-11 10:41:07 +0300 |
|---|---|---|
| committer | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-13 08:17:18 +0300 |
| commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
| tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/tile/lib/spinlock_32.c | |
| parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) | |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/tile/lib/spinlock_32.c')
| -rw-r--r-- | kernel/arch/tile/lib/spinlock_32.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/kernel/arch/tile/lib/spinlock_32.c b/kernel/arch/tile/lib/spinlock_32.c index b34f79aad..88c2a5336 100644 --- a/kernel/arch/tile/lib/spinlock_32.c +++ b/kernel/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); |