Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757081AbYJVRYp (ORCPT ); Wed, 22 Oct 2008 13:24:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751011AbYJVRYc (ORCPT ); Wed, 22 Oct 2008 13:24:32 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:59915 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795AbYJVRYb (ORCPT ); Wed, 22 Oct 2008 13:24:31 -0400 Subject: Re: [PATCH 1/2] Allow rwlocks to re-enable interrupts From: Peter Zijlstra To: Petr Tesarik Cc: linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, tee@sgi.com, Ingo Molnar In-Reply-To: <1224665899.4430.48.camel@elijah.suse.cz> References: <1224664414.4430.33.camel@elijah.suse.cz> <1224664476.4430.38.camel@elijah.suse.cz> <1224665128.15448.4.camel@twins> <1224665899.4430.48.camel@elijah.suse.cz> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Wed, 22 Oct 2008 19:24:31 +0200 Message-Id: <1224696271.20069.8.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1463 Lines: 38 On Wed, 2008-10-22 at 10:58 +0200, Petr Tesarik wrote: > On Wed, 2008-10-22 at 10:45 +0200, Peter Zijlstra wrote: > > On Wed, 2008-10-22 at 10:34 +0200, Petr Tesarik wrote: > > > c b/kernel/spinlock.c > > > index 29ab207..f769d8a 100644 > > > --- a/kernel/spinlock.c > > > +++ b/kernel/spinlock.c > > > @@ -121,7 +121,11 @@ unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock) > > > local_irq_save(flags); > > > preempt_disable(); > > > rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_); > > > +#ifdef CONFIG_LOCKDEP > > > LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock); > > > +#else > > > + _raw_read_lock_flags(lock, &flags); > > > +#endif > > > return flags; > > > } > > > > That should be CONFIG_LOCK_STAT. > > Ugh. Fine with me, but is CONFIG_LOCKDEP correct in _spin_lock_irqsave, > or should it also read CONFIG_LOCK_STAT? Yep. > > But aside from that, I really don't like this change, I'd rather you'd > > create a LOCK_CONTENDED_FLAGS() that can deal with this. > > No problem. I could then also use it for _spin_lock_irqsave, if the > answer to the above question is use CONFIG_LOCK_STAT there as well. If you create LOCK_CONTEDED_FLAGS() the whole issue goes away nicely. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/