From patchwork Tue Oct 10 21:03:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 9997797 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 79104603FF for ; Tue, 10 Oct 2017 21:04:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6BBA528795 for ; Tue, 10 Oct 2017 21:04:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 608E02879B; Tue, 10 Oct 2017 21:04:08 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0E00E28797 for ; Tue, 10 Oct 2017 21:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932985AbdJJVEG (ORCPT ); Tue, 10 Oct 2017 17:04:06 -0400 Received: from esa6.hgst.iphmx.com ([216.71.154.45]:26067 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932984AbdJJVDv (ORCPT ); Tue, 10 Oct 2017 17:03:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1507669432; x=1539205432; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=dGghtftF5P28TMRozlW6VoOO4BEWONkLra2C13+ZeK0=; b=a4eXaEKBDIdfWcq+o/InscwBCRWFNc+qrH1Q9G/9MZnfK9lI6cMwi3Yw S/MH9TR9lTKpTgkrNjEOMCv3qGm9jK5Ss7JUKP9MjAA+Ki9xBvi1NPkzK /qNtX4biiJFmnjxn7fp7EmrWtK8+dHdIZTmWu8etyRGTumhHItYp+fff6 URPRbH4LXK2uoYqdh3uMGtMF0pS9iyq+p9PKFaHWvAh4qqPr88Jqzvulf voPiQ6p4M5ILopVbvU+oj2OHvU20MteQZt9yiOD3Q924WGpRi4olGjZWW EfuPdua+Jjp5zBcjcsigdhkMq1t8NrDmxz8+yD0596GIvWxVziYangSrI A==; X-IronPort-AV: E=Sophos;i="5.43,359,1503331200"; d="scan'208";a="57741122" Received: from sjappemgw11.hgst.com (HELO sjappemgw12.hgst.com) ([199.255.44.62]) by ob1.hgst.iphmx.com with ESMTP; 11 Oct 2017 05:03:48 +0800 Received: from thinkpad-bart.sdcorp.global.sandisk.com (HELO thinkpad-bart.int.fusionio.com) ([10.11.172.152]) by sjappemgw12.hgst.com with ESMTP; 10 Oct 2017 14:03:47 -0700 From: Bart Van Assche To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, Christoph Hellwig , "Martin K . Petersen" , Oleksandr Natalenko , Ming Lei , Bart Van Assche , Hannes Reinecke , Johannes Thumshirn Subject: [PATCH v8 08/10] block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag Date: Tue, 10 Oct 2017 14:03:44 -0700 Message-Id: <20171010210346.14574-9-bart.vanassche@wdc.com> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20171010210346.14574-1-bart.vanassche@wdc.com> References: <20171010210346.14574-1-bart.vanassche@wdc.com> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This flag will be used in the next patch to let the block layer core know whether or not a SCSI request queue has been quiesced. A quiesced SCSI queue namely only processes RQF_PREEMPT requests. Signed-off-by: Bart Van Assche Cc: Ming Lei Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Johannes Thumshirn --- block/blk-core.c | 30 ++++++++++++++++++++++++++++++ block/blk-mq-debugfs.c | 1 + include/linux/blkdev.h | 6 ++++++ 3 files changed, 37 insertions(+) diff --git a/block/blk-core.c b/block/blk-core.c index 842e67e0b7ab..ed992cbd107f 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -346,6 +346,36 @@ void blk_sync_queue(struct request_queue *q) } EXPORT_SYMBOL(blk_sync_queue); +/** + * blk_set_preempt_only - set QUEUE_FLAG_PREEMPT_ONLY + * @q: request queue pointer + * + * Returns the previous value of the PREEMPT_ONLY flag - 0 if the flag was not + * set and 1 if the flag was already set. + */ +int blk_set_preempt_only(struct request_queue *q) +{ + unsigned long flags; + int res; + + spin_lock_irqsave(q->queue_lock, flags); + res = queue_flag_test_and_set(QUEUE_FLAG_PREEMPT_ONLY, q); + spin_unlock_irqrestore(q->queue_lock, flags); + + return res; +} +EXPORT_SYMBOL_GPL(blk_set_preempt_only); + +void blk_clear_preempt_only(struct request_queue *q) +{ + unsigned long flags; + + spin_lock_irqsave(q->queue_lock, flags); + queue_flag_clear(QUEUE_FLAG_PREEMPT_ONLY, q); + spin_unlock_irqrestore(q->queue_lock, flags); +} +EXPORT_SYMBOL_GPL(blk_clear_preempt_only); + /** * __blk_run_queue_uncond - run a queue whether or not it has been stopped * @q: The queue to run diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 7f4a1ba532af..75f31535f280 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -74,6 +74,7 @@ static const char *const blk_queue_flag_name[] = { QUEUE_FLAG_NAME(REGISTERED), QUEUE_FLAG_NAME(SCSI_PASSTHROUGH), QUEUE_FLAG_NAME(QUIESCED), + QUEUE_FLAG_NAME(PREEMPT_ONLY), }; #undef QUEUE_FLAG_NAME diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 3f7b08a9b9ae..89555eea742b 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -630,6 +630,7 @@ struct request_queue { #define QUEUE_FLAG_REGISTERED 26 /* queue has been registered to a disk */ #define QUEUE_FLAG_SCSI_PASSTHROUGH 27 /* queue supports SCSI commands */ #define QUEUE_FLAG_QUIESCED 28 /* queue has been quiesced */ +#define QUEUE_FLAG_PREEMPT_ONLY 29 /* only process REQ_PREEMPT requests */ #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ (1 << QUEUE_FLAG_SAME_COMP) | \ @@ -730,6 +731,11 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ REQ_FAILFAST_DRIVER)) #define blk_queue_quiesced(q) test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags) +#define blk_queue_preempt_only(q) \ + test_bit(QUEUE_FLAG_PREEMPT_ONLY, &(q)->queue_flags) + +extern int blk_set_preempt_only(struct request_queue *q); +extern void blk_clear_preempt_only(struct request_queue *q); static inline bool blk_account_rq(struct request *rq) {