From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755372Ab1HWJfY (ORCPT ); Tue, 23 Aug 2011 05:35:24 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:44548 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754577Ab1HWJfV (ORCPT ); Tue, 23 Aug 2011 05:35:21 -0400 Date: Tue, 23 Aug 2011 05:35:20 -0400 From: Christoph Hellwig To: Dave Chinner Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, khlebnikov@openvz.org Subject: Re: [PATCH 12/13] dcache: remove dentries from LRU before putting on dispose list Message-ID: <20110823093520.GA4938@infradead.org> References: <1314089786-20535-1-git-send-email-david@fromorbit.com> <1314089786-20535-13-git-send-email-david@fromorbit.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1314089786-20535-13-git-send-email-david@fromorbit.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > diff --git a/fs/dcache.c b/fs/dcache.c > index b931415..79bf47c 100644 > --- a/fs/dcache.c > +++ b/fs/dcache.c > @@ -269,10 +269,10 @@ static void dentry_lru_move_list(struct dentry *dentry, struct list_head *list) > spin_lock(&dentry->d_sb->s_dentry_lru_lock); > if (list_empty(&dentry->d_lru)) { > list_add_tail(&dentry->d_lru, list); > - dentry->d_sb->s_nr_dentry_unused++; > - this_cpu_inc(nr_dentry_unused); > } else { > list_move_tail(&dentry->d_lru, list); > + dentry->d_sb->s_nr_dentry_unused--; > + this_cpu_dec(nr_dentry_unused); > } > spin_unlock(&dentry->d_sb->s_dentry_lru_lock); I suspect at this point it might be more obvious to simply remove dentry_lru_move_list. Just call dentry_lru_del to remove it from the lru, and then we can add it to the local dispose list without the need of any locking, similar to how it is done for inodes already. > if (dentry->d_count) { > - dentry_lru_del(dentry); > spin_unlock(&dentry->d_lock); > continue; > } > @@ -789,6 +794,8 @@ relock: > spin_unlock(&dentry->d_lock); > } else { > list_move_tail(&dentry->d_lru, &tmp); > + this_cpu_dec(nr_dentry_unused); > + sb->s_nr_dentry_unused--; It might be more obvious to use __dentry_lru_del + an opencoded list_add here.