From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [patch 2/4] net: use mutex_is_locked() for ASSERT_RTNL() Date: Fri, 14 Dec 2007 00:22:09 -0800 Message-ID: <20071214002209.ac748206.akpm@linux-foundation.org> References: <200712140002.lBE02aGO025491@imap1.linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, netdev@vger.kernel.org To: Herbert Xu Return-path: Received: from smtp2.linux-foundation.org ([207.189.120.14]:53353 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753427AbXLNIXT (ORCPT ); Fri, 14 Dec 2007 03:23:19 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Fri, 14 Dec 2007 16:10:44 +0800 Herbert Xu wrote: > akpm@linux-foundation.org wrote: > > > > diff -puN drivers/net/cxgb3/cxgb3_main.c~net-use-mutex_is_locked-for-assert_rtnl drivers/net/cxgb3/cxgb3_main.c > > --- a/drivers/net/cxgb3/cxgb3_main.c~net-use-mutex_is_locked-for-assert_rtnl > > +++ a/drivers/net/cxgb3/cxgb3_main.c > > @@ -2191,7 +2191,7 @@ static void check_t3b2_mac(struct adapte > > { > > int i; > > > > - if (!rtnl_trylock()) /* synchronize with ifdown */ > > + if (rtnl_is_locked()) /* synchronize with ifdown */ > > return; > > > > for_each_port(adapter, i) { > > @@ -2219,7 +2219,6 @@ static void check_t3b2_mac(struct adapte > > p->mac.stats.num_resets++; > > } > > } > > - rtnl_unlock(); > > This doesn't look right. It seems that they really want trylock > here so we should just fix it by removing the bang. doh. > Also, does ASSERT_RTNL still warn when someone calls it from an > atomic context? We definitely don't want to lose that check. I don't see how it could warn about that. Nor should it - one might want to check that rtnl_lock is held inside preempt_disable() or spin_lock or whatever. It might make sense to warn if ASSERT_RTNL is called in in_interrupt() contexts though.