From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3621828EB for ; Mon, 30 Jan 2023 13:56:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8F3C9C433EF; Mon, 30 Jan 2023 13:56:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675087009; bh=U6YvlK8tcuoTFfKwo97HsGcAlZ6VlEClNHr4LJZxba4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n3t5sA6KBfW4WlGT5rbHP2DKDaSFbQYHN1b7BxMKYBW11edf1s5jBbsBSvVo5VD1H oQXjONPE4vuEhDBbpVRaEsZON5GKfWuyBQ+TU71GGc9o/hLgPnhZDVW4sySkIMWIwv 5uXfcqUP69QU+l+zOEwQ4gpjQ4FBI/GzHaR+lQBM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tejun Heo , Dan Carpenter , Christoph Hellwig , Luis Chamberlain , Jens Axboe , Sasha Levin Subject: [PATCH 6.1 040/313] block: Drop spurious might_sleep() from blk_put_queue() Date: Mon, 30 Jan 2023 14:47:55 +0100 Message-Id: <20230130134338.554818046@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130134336.532886729@linuxfoundation.org> References: <20230130134336.532886729@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Tejun Heo [ Upstream commit 49e4d04f0486117ac57a97890eb1db6d52bf82b3 ] Dan reports the following smatch detected the following: block/blk-cgroup.c:1863 blkcg_schedule_throttle() warn: sleeping in atomic context caused by blkcg_schedule_throttle() calling blk_put_queue() in an non-sleepable context. blk_put_queue() acquired might_sleep() in 63f93fd6fa57 ("block: mark blk_put_queue as potentially blocking") which transferred the might_sleep() from blk_free_queue(). blk_free_queue() acquired might_sleep() in e8c7d14ac6c3 ("block: revert back to synchronous request_queue removal") while turning request_queue removal synchronous. However, this isn't necessary as nothing in the free path actually requires sleeping. It's pretty unusual to require a sleeping context in a put operation and it's not needed in the first place. Let's drop it. Signed-off-by: Tejun Heo Reported-by: Dan Carpenter Link: https://lkml.kernel.org/r/Y7g3L6fntnTtOm63@kili Cc: Christoph Hellwig Cc: Luis Chamberlain Fixes: e8c7d14ac6c3 ("block: revert back to synchronous request_queue removal") # v5.9+ Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/Y7iFwjN+XzWvLv3y@slm.duckdns.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/blk-core.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 815ffce6b988..f5ae527fb0c3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -282,12 +282,9 @@ static void blk_free_queue(struct request_queue *q) * * Decrements the refcount of the request_queue and free it when the refcount * reaches 0. - * - * Context: Can sleep. */ void blk_put_queue(struct request_queue *q) { - might_sleep(); if (refcount_dec_and_test(&q->refs)) blk_free_queue(q); } -- 2.39.0