Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262717AbVAFErr (ORCPT ); Wed, 5 Jan 2005 23:47:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262718AbVAFErr (ORCPT ); Wed, 5 Jan 2005 23:47:47 -0500 Received: from fw.osdl.org ([65.172.181.6]:9870 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262717AbVAFErl (ORCPT ); Wed, 5 Jan 2005 23:47:41 -0500 Date: Wed, 5 Jan 2005 20:47:06 -0800 From: Andrew Morton To: Nick Piggin Cc: riel@redhat.com, marcelo.tosatti@cyclades.com, andrea@suse.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH][5/?] count writeback pages in nr_scanned Message-Id: <20050105204706.0781d672.akpm@osdl.org> In-Reply-To: <41DCC014.80007@yahoo.com.au> References: <20050105020859.3192a298.akpm@osdl.org> <20050105180651.GD4597@dualathlon.random> <20050105174934.GC15739@logos.cnet> <20050105134457.03aca488.akpm@osdl.org> <20050105203217.GB17265@logos.cnet> <41DC7D86.8050609@yahoo.com.au> <20050105173624.5c3189b9.akpm@osdl.org> <41DCB577.9000205@yahoo.com.au> <20050105202611.65eb82cf.akpm@osdl.org> <41DCC014.80007@yahoo.com.au> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 785 Lines: 21 Nick Piggin wrote: > > > If the queue is not congested, blk_congestion_wait() will still sleep. See > > freed_request(). > > > > Hmm... doesn't look like it to me: > > if (rl->count[rw] < queue_congestion_off_threshold(q)) > clear_queue_congested(q, rw); > > And clear_queue_congested does an unconditional wakeup (if there > is someone sleeping on the congestion queue). That's my point. blk_congestion_wait() will always sleep, regardless of the queue's congestion state. - 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/