From patchwork Wed May 15 03:03:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 10944201 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AE411112C for ; Wed, 15 May 2019 03:03:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9D7E92890F for ; Wed, 15 May 2019 03:03:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 91F4E28917; Wed, 15 May 2019 03:03:36 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham 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 3175E28910 for ; Wed, 15 May 2019 03:03:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726295AbfEODDd (ORCPT ); Tue, 14 May 2019 23:03:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35558 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726261AbfEODDd (ORCPT ); Tue, 14 May 2019 23:03:33 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0784D81F1B; Wed, 15 May 2019 03:03:33 +0000 (UTC) Received: from localhost (ovpn-8-22.pek2.redhat.com [10.72.8.22]) by smtp.corp.redhat.com (Postfix) with ESMTP id EE5775C1A3; Wed, 15 May 2019 03:03:29 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Ming Lei , Christoph Hellwig , Bart Van Assche Subject: [PATCH 2/3] block: don't protect generic_make_request_checks with blk_queue_enter Date: Wed, 15 May 2019 11:03:09 +0800 Message-Id: <20190515030310.20393-3-ming.lei@redhat.com> In-Reply-To: <20190515030310.20393-1-ming.lei@redhat.com> References: <20190515030310.20393-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 15 May 2019 03:03:33 +0000 (UTC) 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 Now a063057d7c73 ("block: Fix a race between request queue removal and the block cgroup controller") has been reverted, and blkcg_exit_queue() won't be called in blk_cleanup_queue() any more. So don't need to protect generic_make_request_checks() with blk_queue_enter(), then the total mess can be cleaned. 37f9579f4c31 ("blk-mq: Avoid that submitting a bio concurrently with device removal triggers a crash") is reverted. Cc: Christoph Hellwig Cc: Bart Van Assche Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig --- block/blk-core.c | 37 ++++++------------------------------- 1 file changed, 6 insertions(+), 31 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 2af1e54870e6..bca63e545f05 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -956,22 +956,8 @@ blk_qc_t generic_make_request(struct bio *bio) * yet. */ struct bio_list bio_list_on_stack[2]; - blk_mq_req_flags_t flags = 0; - struct request_queue *q = bio->bi_disk->queue; blk_qc_t ret = BLK_QC_T_NONE; - if (bio->bi_opf & REQ_NOWAIT) - flags = BLK_MQ_REQ_NOWAIT; - if (bio_flagged(bio, BIO_QUEUE_ENTERED)) - blk_queue_enter_live(q); - else if (blk_queue_enter(q, flags) < 0) { - if (!blk_queue_dying(q) && (bio->bi_opf & REQ_NOWAIT)) - bio_wouldblock_error(bio); - else - bio_io_error(bio); - return ret; - } - if (!generic_make_request_checks(bio)) goto out; @@ -1008,22 +994,11 @@ blk_qc_t generic_make_request(struct bio *bio) bio_list_init(&bio_list_on_stack[0]); current->bio_list = bio_list_on_stack; do { - bool enter_succeeded = true; - - if (unlikely(q != bio->bi_disk->queue)) { - if (q) - blk_queue_exit(q); - q = bio->bi_disk->queue; - flags = 0; - if (bio->bi_opf & REQ_NOWAIT) - flags = BLK_MQ_REQ_NOWAIT; - if (blk_queue_enter(q, flags) < 0) { - enter_succeeded = false; - q = NULL; - } - } + struct request_queue *q = bio->bi_disk->queue; + blk_mq_req_flags_t flags = bio->bi_opf & REQ_NOWAIT ? + BLK_MQ_REQ_NOWAIT : 0; - if (enter_succeeded) { + if (likely(blk_queue_enter(q, flags) == 0)) { struct bio_list lower, same; /* Create a fresh bio_list for all subordinate requests */ @@ -1031,6 +1006,8 @@ blk_qc_t generic_make_request(struct bio *bio) bio_list_init(&bio_list_on_stack[0]); ret = q->make_request_fn(q, bio); + blk_queue_exit(q); + /* sort new bios into those for a lower level * and those for the same level */ @@ -1057,8 +1034,6 @@ blk_qc_t generic_make_request(struct bio *bio) current->bio_list = NULL; /* deactivate */ out: - if (q) - blk_queue_exit(q); return ret; } EXPORT_SYMBOL(generic_make_request);