Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756097AbZCNOdo (ORCPT ); Sat, 14 Mar 2009 10:33:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752328AbZCNOdf (ORCPT ); Sat, 14 Mar 2009 10:33:35 -0400 Received: from x35.xmailserver.org ([64.71.152.41]:49410 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751765AbZCNOde (ORCPT ); Sat, 14 Mar 2009 10:33:34 -0400 X-AuthUser: davidel@xmailserver.org Date: Sat, 14 Mar 2009 07:32:19 -0700 (PDT) From: Davide Libenzi X-X-Sender: davide@makko.or.mcafeemobile.com To: Trond Myklebust cc: Andrew Morton , Eric Dumazet , Jeff Moyer , Avi Kivity , linux-aio , zach.brown@oracle.com, Benjamin LaHaise , Linux Kernel Mailing List , Christoph Lameter Subject: Re: [PATCH] fs: fput() can be called from interrupt context In-Reply-To: <1237003328.7265.98.camel@heimdal.trondhjem.org> Message-ID: References: <49B54143.1010607@redhat.com> <49B57CB0.5020300@cosmosbay.com> <49B875F7.3030305@cosmosbay.com> <49B87CFE.4000701@cosmosbay.com> <49B89B22.7080303@cosmosbay.com> <20090311224712.fb8db075.akpm@linux-foundation.org> <49B8A75E.6040409@cosmosbay.com> <20090311233903.f036027a.akpm@linux-foundation.org> <1236986902.7265.73.camel@heimdal.trondhjem.org> <1237003328.7265.98.camel@heimdal.trondhjem.org> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1480 Lines: 37 On Sat, 14 Mar 2009, Trond Myklebust wrote: > > Did I miss something? This wouldn't be (eventually) on keventd shoulders, > > but on aio work queue (aio_wq). > > I guess we could do the same optimization we're already doing for ki_filp, > > for ki_eventfd ... > > Last I checked, a call to schedule_work(&fddef->wq) would still run > fd_defer_queue() under keventd. Oh, you were commenting about Eric's patch-set. I thought you were talking about the current status (that my reply to Andrew was hinting to), and was wondering for a while from where fd_defer_queue() came from. > That said, even if you were to run it under aio_wq, the argument remains > the same: do you really want to add potentially long lasting sleeps onto > a work queue that was designed to service fast i/o requests? No, and if you roll back, you couldn't miss to notice that mine was a question about the f_count direct manipulation/optimization. We can do the same optimization for eventfd, although both will fall in the aio kthread in any case, if we're holding the last insteance of the file* (that I guess we can consider an unlikely case). Dunno how worth it could be adding a new NCPU*thread(s) just to handle delayed fputs. - Davide -- 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/