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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 932C8C43333 for ; Wed, 23 Dec 2020 02:50:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6B3302312E for ; Wed, 23 Dec 2020 02:50:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730756AbgLWCtx (ORCPT ); Tue, 22 Dec 2020 21:49:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:49956 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729537AbgLWCWC (ORCPT ); Tue, 22 Dec 2020 21:22:02 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id BBA7B221E5; Wed, 23 Dec 2020 02:21:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1608690106; bh=VE727nvXGpFomCq6VgNh6/FXE50Z43folyCCKCVosUk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NYWF/+nef7NqDDkU0fcmkqppX5DfT9q7mYGo9aloHvK+pB7YJHtvU6fvM+DA+iW9m Li/Fi5Y+k8lBIzffG8ZcGZhIdDIu8litnGndQjySvsINWrFKG/Skqm8sUINbYy8IQy uq3De5CqmFP4g+BUUtS5/nSv87JulNc1/WM+/vLwCCT8yX7m8D92UZTMiKAR3HULyJ Ukp6J/X52+AwJoulaRZMoZ9pwwam7d7rXxMbxIj7owQ5Hk2q0jFD7ycOprPYmYluFh ZiIgj5Nm2EvAJlkrjrTQRrH7BgDVrteO698awIgbKZl57V9w09NDN0fnKaUYWpiyVy ga462uDmarR+g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jaegeuk Kim , Can Guo , "Martin K . Petersen" , Sasha Levin , linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 35/87] scsi: ufs: Atomic update for clkgating_enable Date: Tue, 22 Dec 2020 21:20:11 -0500 Message-Id: <20201223022103.2792705-35-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201223022103.2792705-1-sashal@kernel.org> References: <20201223022103.2792705-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jaegeuk Kim [ Upstream commit b664511297644eac34038df877b3ad7bcaa81913 ] While running a stress test which enables/disables clkgating, we occasionally hit device timeout. This patch avoids a subtle race condition to address it. Link: https://lore.kernel.org/r/20201117165839.1643377-3-jaegeuk@kernel.org Reviewed-by: Can Guo Signed-off-by: Jaegeuk Kim Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/ufs/ufshcd.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 7e4e6e982055e..b2fd853f07573 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1766,19 +1766,19 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev, return -EINVAL; value = !!value; + + spin_lock_irqsave(hba->host->host_lock, flags); if (value == hba->clk_gating.is_enabled) goto out; - if (value) { - ufshcd_release(hba); - } else { - spin_lock_irqsave(hba->host->host_lock, flags); + if (value) + __ufshcd_release(hba); + else hba->clk_gating.active_reqs++; - spin_unlock_irqrestore(hba->host->host_lock, flags); - } hba->clk_gating.is_enabled = value; out: + spin_unlock_irqrestore(hba->host->host_lock, flags); return count; } -- 2.27.0