Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S968191Ab3HIQrf (ORCPT ); Fri, 9 Aug 2013 12:47:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38051 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S968137Ab3HIQrc (ORCPT ); Fri, 9 Aug 2013 12:47:32 -0400 Date: Fri, 9 Aug 2013 18:46:32 +0200 From: Alexander Gordeev To: Jens Axboe Cc: Tejun Heo , "Nicholas A. Bellinger" , James Bottomley , Mike Christie , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, Jeff Garzik , linux-scsi Subject: Re: [PATCH RESEND 0/1] AHCI: Optimize interrupt processing Message-ID: <20130809164632.GC25306@dhcp-26-207.brq.redhat.com> References: <1374527436.7397.1145.camel@haakon3.risingtidesystems.com> <20130725101641.GB31994@dhcp-26-207.brq.redhat.com> <1374790082.7397.1411.camel@haakon3.risingtidesystems.com> <20130726020928.GL29296@kernel.dk> <1374873276.7397.1512.camel@haakon3.risingtidesystems.com> <20130729114653.GB20951@mtj.dyndns.org> <20130809082335.GA25306@dhcp-26-207.brq.redhat.com> <5204FBA6.6040001@kernel.dk> <20130809150744.GB25306@dhcp-26-207.brq.redhat.com> <52051033.8050605@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52051033.8050605@kernel.dk> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1504 Lines: 42 On Fri, Aug 09, 2013 at 09:52:19AM -0600, Jens Axboe wrote: > On 08/09/2013 09:07 AM, Alexander Gordeev wrote: > > diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c > > index dcbc2a4..b131a48 100644 > > --- a/block/blk-mq-tag.c > > +++ b/block/blk-mq-tag.c > > @@ -468,10 +468,9 @@ struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, > > * Rest of the tags start at the queue list > > */ > > tags->nr_free = 0; > > - while (nr_tags - tags->nr_reserved) { > > + while (nr_tags--) { > > tags->freelist[tags->nr_free] = tags->nr_free + > > tags->nr_reserved; > > - nr_tags--; > > tags->nr_free++; > > } > > I misremembered, just checked the code. I think I used to have it like I > described, but changed it since I thought it would be more logical to > pass in full depth, and then what part of that is reserved. Looking at > the current code, your patch looks correct as-is. Ok, then a whole series "[PATCH 0/3] blk-mq: Avoid effects of a weird queue depth" (I posted earlier in a separate thread) should make sense. Besides the hunk above it limits the per-cpu cache size and sanity-checks total vs reserved length. I can resubmit if you want. > > -- > Jens Axboe > -- Regards, Alexander Gordeev agordeev@redhat.com -- 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/