Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754074AbZJUPby (ORCPT ); Wed, 21 Oct 2009 11:31:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753953AbZJUPbx (ORCPT ); Wed, 21 Oct 2009 11:31:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34180 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753540AbZJUPbx (ORCPT ); Wed, 21 Oct 2009 11:31:53 -0400 From: Jeff Moyer To: Corrado Zoccolo Cc: "Linux-Kernel" , Jens Axboe Subject: Re: [RFC V2 PATCH 2/5] cfq-iosched: preparation to handle multiple service trees References: <200910202012.00196.czoccolo@gmail.com> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Wed, 21 Oct 2009 11:31:52 -0400 In-Reply-To: <200910202012.00196.czoccolo@gmail.com> (Corrado Zoccolo's message of "Tue, 20 Oct 2009 20:11:59 +0200") Message-ID: User-Agent: Gnus/5.110011 (No Gnus v0.11) Emacs/23.1 (gnu/linux) 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: 942 Lines: 28 Corrado Zoccolo writes: > We embed a pointer to the service tree in each queue, to handle multiple > service trees easily. > Service trees are enriched with a counter. > cfq_add_rq_rb is invoked after putting the rq in the fifo, to ensure > that all fields in rq are properly initialized. > > @@ -115,6 +116,9 @@ struct cfq_queue { > unsigned short ioprio_class, org_ioprio_class; > > pid_t pid; > + > + struct cfq_rb_root *service_tree; > + struct cfq_io_context *cic; > }; This change worries me. For async queues, there is not a 1:1 mapping between cfqq and cic. With my forthcoming close cooperator changes, the same will be true for sync queues. Cheers, Jeff -- 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/