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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E1CDC433FF for ; Fri, 2 Aug 2019 13:36:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EBC9C21726 for ; Fri, 2 Aug 2019 13:36:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564752988; bh=rL23VPL5LiMMzW9WGs9qMwcc3Mu20T2X1ST1LCulyRM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2PcC+7wy0YbErHVRMKGpgf4KOaliJ1rtlkaCFFTkRZfw0TKn9iQGVdpeAm5tI8WBf P2I6NAl4cO+qrxqaiGOW+yYJ/4T0yw9Ea06b3e0/qc73fyz5CiEgAnz4KOLjeNaHRI qQt6Ijhl4SXYxFIkkNkTagaS7wHJisO9JR/aT/uo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393314AbfHBNUP (ORCPT ); Fri, 2 Aug 2019 09:20:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:58426 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393280AbfHBNUH (ORCPT ); Fri, 2 Aug 2019 09:20:07 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 711662087C; Fri, 2 Aug 2019 13:20:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564752006; bh=rL23VPL5LiMMzW9WGs9qMwcc3Mu20T2X1ST1LCulyRM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=07nHCnBRznje0SLb5zH9zB5lwXFnmx6LzHynYrYO6E75dO6Bs+VtXevx5jwjowNa4 OZd9cLkoJKZrOctxVPdQ8VLWEgkE8OZVhMHTBnxztxeVT0w2ZiRhM4rTMLqlirXBJS ugUnSZsHqVUaihXCNJpf5uLzTjzgnxrNTLiUbiqU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Josef Bacik , Oleg Nesterov , Jens Axboe , Sasha Levin , linux-block@vger.kernel.org Subject: [PATCH AUTOSEL 5.2 12/76] rq-qos: don't reset has_sleepers on spurious wakeups Date: Fri, 2 Aug 2019 09:18:46 -0400 Message-Id: <20190802131951.11600-12-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190802131951.11600-1-sashal@kernel.org> References: <20190802131951.11600-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josef Bacik [ Upstream commit 64e7ea875ef63b2801be7954cf7257d1bfccc266 ] If we raced with somebody else getting an inflight counter we could fail to get an inflight counter with no sleepers on the list, and thus need to go to sleep. In this case has_sleepers should be true because we are now relying on the waker to get our inflight counter for us. And in the case of spurious wakeups we'd still want this to be the case. So set has_sleepers to true if we went to sleep to make sure we're woken up the proper way. Reviewed-by: Oleg Nesterov Signed-off-by: Josef Bacik Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/blk-rq-qos.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c index 659ccb8b693fa..e5d75280b431e 100644 --- a/block/blk-rq-qos.c +++ b/block/blk-rq-qos.c @@ -260,7 +260,7 @@ void rq_qos_wait(struct rq_wait *rqw, void *private_data, break; } io_schedule(); - has_sleeper = false; + has_sleeper = true; } while (1); finish_wait(&rqw->wait, &data.wq); } -- 2.20.1