On 11/12, Peter Zijlstra wrote: > > On Thu, Nov 12, 2015 at 07:38:07PM +0100, Oleg Nesterov wrote: > > It seems that PPC needs to define smp_mb__before_spinlock() as full mb(), > > no? > > It does: > > arch/powerpc/include/asm/barrier.h:#define smp_mb__before_spinlock() smp_mb()
Ah, indeed, thanks. And given that it also defines smp_mb__after_unlock_lock() as smp_mb(), I am starting to understand how it can help to avoid the races with spin_unlock_wait() in (for example) do_exit(). But as Boqun has already mentioned, this means that mb__after_unlock_lock() has the new meaning which should be documented. Hmm. And 12d560f4 "Privatize smp_mb__after_unlock_lock()" should be reverted then ;) Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
