From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH RESEND 0/1] AHCI: Optimize interrupt processing Date: Fri, 09 Aug 2013 09:52:19 -0600 Message-ID: <52051033.8050605@kernel.dk> References: <1374296162.7397.1098.camel@haakon3.risingtidesystems.com> <20130722150359.GA16564@dhcp-26-207.brq.redhat.com> <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> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130809150744.GB25306@dhcp-26-207.brq.redhat.com> Sender: linux-scsi-owner@vger.kernel.org To: Alexander Gordeev Cc: Tejun Heo , "Nicholas A. Bellinger" , James Bottomley , Mike Christie , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, Jeff Garzik , linux-scsi List-Id: linux-ide@vger.kernel.org On 08/09/2013 09:07 AM, Alexander Gordeev wrote: > On Fri, Aug 09, 2013 at 08:24:38AM -0600, Jens Axboe wrote: >> On 08/09/2013 02:23 AM, Alexander Gordeev wrote: >>> + ap->qc_tags = blk_mq_init_tags(ATA_MAX_QUEUE, 1, NUMA_NO_NODE); >>> + if (!ap->qc_tags) { >>> + kfree(ap); >>> + return NULL; >>> + } >> >> This should be blk_mq_init_tags(ATA_MAX_QUEUE - 1, 1, ...) since the >> total depth is normal_tags + reserved_tags. > > Aha.. If blk_mq_init_tags() should be like this then? > > 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. -- Jens Axboe