From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D1E2CDB47E for ; Thu, 19 Oct 2023 00:15:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231349AbjJSAPQ (ORCPT ); Wed, 18 Oct 2023 20:15:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57344 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229632AbjJSAPP (ORCPT ); Wed, 18 Oct 2023 20:15:15 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0E8AA119; Wed, 18 Oct 2023 17:15:14 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C2C6C433C8; Thu, 19 Oct 2023 00:15:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1697674513; bh=za4ERhTBMaBikZmJUpGYnyH3Cm4WwlpTpeRBqZaj4kA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=eCw+5PdId35n0330no/fkXgruo2AcPAZsgDBLW5rY7SQ/hg1vpzYymt36Ul5vL0Fy Wb4RTxojK/Hmm7A9PWj+JvOC+ldUL5XTwUs4sCgzg/j4FgF1bcwwD0FVPWzYwS5y1g H0481avUi0/Zrm7zTIbELC1TY1MBI7RhMgwQWr0tcEXbUGXu3DFyP81AiuU9DI44sM mswM6/OF85XWlbdcL3/euk/grI6HjBE0ChzhdnBIEPGIQgJOPrfx5q3lU8Mu6oigsL 85zGm7WJzTbjDTsmYbd1q6c8h0CLHhxmZHF/WciASKjdp066SVqV3ZHwSZ6wsAvUdq TpFiFmcfQlMCQ== Message-ID: <5a58c56f-5558-43d5-adc4-bc379f87ddbf@kernel.org> Date: Thu, 19 Oct 2023 09:15:10 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v13 03/18] block: Preserve the order of requeued zoned writes To: Bart Van Assche , Jens Axboe Cc: linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, "Martin K . Petersen" , Christoph Hellwig , Ming Lei , Hannes Reinecke References: <20231018175602.2148415-1-bvanassche@acm.org> <20231018175602.2148415-4-bvanassche@acm.org> Content-Language: en-US From: Damien Le Moal Organization: Western Digital Research In-Reply-To: <20231018175602.2148415-4-bvanassche@acm.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 10/19/23 02:54, Bart Van Assche wrote: > blk_mq_requeue_work() inserts requeued requests in front of other > requests. This is fine for all request types except for sequential zoned > writes. Hence this patch. > > Note: moving this functionality into the mq-deadline I/O scheduler is > not an option because we want to be able to use zoned storage without > I/O scheduler. > > Cc: Christoph Hellwig > Cc: Damien Le Moal > Cc: Ming Lei > Cc: Hannes Reinecke > Signed-off-by: Bart Van Assche > --- > block/blk-mq.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 502dafa76716..ce6ddb249959 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -1485,7 +1485,9 @@ static void blk_mq_requeue_work(struct work_struct *work) > blk_mq_request_bypass_insert(rq, 0); > } else { > list_del_init(&rq->queuelist); > - blk_mq_insert_request(rq, BLK_MQ_INSERT_AT_HEAD); > + blk_mq_insert_request(rq, > + !blk_rq_is_seq_zoned_write(rq) ? > + BLK_MQ_INSERT_AT_HEAD : 0); Something like: } else { blk_insert_t flags = BLK_MQ_INSERT_AT_HEAD; if (blk_rq_is_seq_zoned_write(rq)) flags = 0; blk_mq_insert_request(rq, flags); } would be a lot easier to read in my opinion. -- Damien Le Moal Western Digital Research