[PATCH 1/2] ipc/sem.c: Avoid using spin_unlock_wait()

a) The ACQUIRE in spin_lock() applies to the read, not to the store, at least for powerpc. This forces to add a smp_mb() into the fast path. b) The memory barrier provided by spin_unlock_wait() is right now arch dependent. Therefore: Use spin_lock()/spin_unlock() instead of spin_unlock_wait(). A

[PATCH 1/2] ipc/sem.c: Avoid using spin_unlock_wait()

a) The ACQUIRE in spin_lock() applies to the read, not to the store, at least for powerpc. This forces to add a smp_mb() into the fast path. b) The memory barrier provided by spin_unlock_wait() is right now arch dependent. Therefore: Use spin_lock()/spin_unlock() instead of spin_unlock_wait(). A