From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754576AbYEWEXM (ORCPT ); Fri, 23 May 2008 00:23:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751147AbYEWEWz (ORCPT ); Fri, 23 May 2008 00:22:55 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:50029 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751016AbYEWEWy (ORCPT ); Fri, 23 May 2008 00:22:54 -0400 Date: Fri, 23 May 2008 14:22:31 +1000 From: David Chinner To: Kentaro Makita Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org, dgc@sgi.com, viro@ZenIV.linux.org.uk, harvey.harrison@gmail.com Subject: Re: [PATCH][RFC]fix soft lock up at NFS mount by per-SB LRU-list of unused dentries Message-ID: <20080523042231.GJ173056135@sgi.com> References: <4834D8DA.30907@np.css.fujitsu.com> <20080522225608.GZ173056135@sgi.com> <483628B7.1080704@np.css.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <483628B7.1080704@np.css.fujitsu.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 23, 2008 at 11:15:19AM +0900, Kentaro Makita wrote: > Hi, David > > Thank you for reviewing the patch. > I'd fix coding style issues at next post. And,... > > David Chinner wrote: > > On Thu, May 22, 2008 at 11:22:18AM +0900, Kentaro Makita wrote: > >> + } > >> + } > >> + } > > > > I'm wondering if this loop is an excessively long time to be holding the > > dcache_lock. I guess the hol dtime is limited by the size of *count being > > passed in. I think we could also do a: > > > > cond_resched_lock(&dcache_lock); > > > > in the loop here to prevent this from occurring.... > Did you mean: > - scan sb->s_dentry_lru and move dentries to temporary list > with lock held > - cond_resched_lock(&dcache_lock); > - prune dentries on temporary list > Is that right? No, I meant while scanning sb->s_dentry_lru. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group