From patchwork Fri Dec 23 12:52:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kemeng Shi X-Patchwork-Id: 13080661 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 B0ED0C4332F for ; Fri, 23 Dec 2022 04:53:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229997AbiLWExe (ORCPT ); Thu, 22 Dec 2022 23:53:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51896 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229627AbiLWExd (ORCPT ); Thu, 22 Dec 2022 23:53:33 -0500 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 32CC812771; Thu, 22 Dec 2022 20:53:31 -0800 (PST) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4NdZZG0T4gz4f3s5w; Fri, 23 Dec 2022 12:53:26 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgDXjbFHNKVjpOduAQ--.93S3; Fri, 23 Dec 2022 12:53:29 +0800 (CST) From: Kemeng Shi To: axboe@kernel.dk, dwagner@suse.de, hare@suse.de, ming.lei@redhat.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Cc: hch@lst.de, john.garry@huawei.com, shikemeng@huaweicloud.com Subject: [PATCH 01/13] blk-mq: avoid sleep in blk_mq_alloc_request_hctx Date: Fri, 23 Dec 2022 20:52:11 +0800 Message-Id: <20221223125223.1687670-2-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20221223125223.1687670-1-shikemeng@huaweicloud.com> References: <20221223125223.1687670-1-shikemeng@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDXjbFHNKVjpOduAQ--.93S3 X-Coremail-Antispam: 1UD129KBjvJXoW7uF1rZw13Kw47GF13JFW8JFb_yoW8CFW7pr W7ta1jyrn0934xCFyIy39xW3y7Cws7ur9rGF1aq34Sv3yxKr1vkF4UZr48WF1xAFs7Jw45 J34rtw1UXr9F93DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBK14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2jI8I6cxK62vIxIIY0VWUZVW8XwA2048vs2IY02 0E87I2jVAFwI0_Jr4l82xGYIkIc2x26xkF7I0E14v26r1I6r4UM28lY4IEw2IIxxk0rwA2 F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjx v20xvEc7CjxVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E 87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64 kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm 72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYx C7MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_ Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x 0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8 JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIx AIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7sRE2NtUUUUUU= = X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Commit 1f5bd336b9150 ("blk-mq: add blk_mq_alloc_request_hctx") add blk_mq_alloc_request_hctx to send commands to a specific queue. If BLK_MQ_REQ_NOWAIT is not set in tag allocation, we may change to different hctx after sleep and get tag from unexpected hctx. So BLK_MQ_REQ_NOWAIT must be set in flags for blk_mq_alloc_request_hctx. After commit 600c3b0cea784 ("blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx"), blk_mq_alloc_request_hctx return -EINVAL if both BLK_MQ_REQ_NOWAIT and BLK_MQ_REQ_RESERVED are not set instead of if BLK_MQ_REQ_NOWAIT is not set. So if BLK_MQ_REQ_NOWAIT is not set and BLK_MQ_REQ_RESERVED is set, blk_mq_alloc_request_hctx could alloc tag from unexpected hctx. I guess what we need here is that return -EINVAL if either BLK_MQ_REQ_NOWAIT or BLK_MQ_REQ_RESERVED is not set. Currently both BLK_MQ_REQ_NOWAIT and BLK_MQ_REQ_RESERVED will be set if specific hctx is needed in nvme_auth_submit, nvmf_connect_io_queue and nvmf_connect_admin_queue. Fix the potential BLK_MQ_REQ_NOWAIT missed case in future. Fixes: 600c3b0cea78 ("blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx") Signed-off-by: Kemeng Shi --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 4e6b3ccd4989..988812811db9 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -657,7 +657,7 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, * allocator for this for the rare use case of a command tied to * a specific queue. */ - if (WARN_ON_ONCE(!(flags & (BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED)))) + if (WARN_ON_ONCE(((!flags) & (BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED)))) return ERR_PTR(-EINVAL); if (hctx_idx >= q->nr_hw_queues)