From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chuck Lever Subject: Re: [PATCH 08/15] SUNRPC: Ensure rpcauth_prune_expired() respects the nr_to_scan parameter Date: Fri, 14 May 2010 12:34:53 -0400 Message-ID: <4BED7BAD.20509@oracle.com> References: <1273784901-25599-1-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-2-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-3-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-4-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-5-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-6-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-7-git-send-email-Trond.Myklebust@netapp.com> <1273784901-25599-8-git-send-email-Trond.Myklebust@netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linux-nfs@vger.kernel.org To: Trond Myklebust Return-path: Received: from rcsinet10.oracle.com ([148.87.113.121]:55293 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755094Ab0ENQfL (ORCPT ); Fri, 14 May 2010 12:35:11 -0400 In-Reply-To: <1273784901-25599-8-git-send-email-Trond.Myklebust@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On 05/13/10 05:08 PM, Trond Myklebust wrote: > Signed-off-by: Trond Myklebust > --- > net/sunrpc/auth.c | 5 ++--- > 1 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c > index 2213dc5..5fb02ac 100644 > --- a/net/sunrpc/auth.c > +++ b/net/sunrpc/auth.c > @@ -236,6 +236,8 @@ rpcauth_prune_expired(struct list_head *free, int nr_to_scan) > > list_for_each_entry_safe(cred, next,&cred_unused, cr_lru) { > > + if (nr_to_scan-- == 0) > + break; > /* > * Enforce a 60 second garbage collection moratorium > * Note that the cred_unused list must be time-ordered. > @@ -255,11 +257,8 @@ rpcauth_prune_expired(struct list_head *free, int nr_to_scan) > get_rpccred(cred); > list_add_tail(&cred->cr_lru, free); > rpcauth_unhash_cred_locked(cred); > - nr_to_scan--; > } > spin_unlock(cache_lock); > - if (nr_to_scan == 0) > - break; > } > return (number_cred_unused / 100) * sysctl_vfs_cache_pressure; > } It looks to me like the mm calls our cache shrinker with nr_to_scan set to zero when it just wants this return value, and nothing more. But the logic here seems to assume that nr_to_scan == 0 means shrink as much as you can. Am I reading this correctly?