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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 880BBC2D0DB for ; Fri, 24 Jan 2020 18:07:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 61FB52077C for ; Fri, 24 Jan 2020 18:07:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="CEDiPIQ3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391184AbgAXSHj (ORCPT ); Fri, 24 Jan 2020 13:07:39 -0500 Received: from mail25.static.mailgun.info ([104.130.122.25]:44151 "EHLO mail25.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390947AbgAXSHi (ORCPT ); Fri, 24 Jan 2020 13:07:38 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1579889258; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=FsdPjpNmzNHjRlbx8RXh1YzktL6/JfX/33KXX8v4t8Y=; b=CEDiPIQ3sOppK0cjWGljCcVrfGC2T8H8iN0QXevL291sUt3ke76rrT9gUjt0uzhYVyWDoQOL maFMXZk9VqEzebEsSw/7mHqSig9jKKZGu8vF31w7vYllbFqFsO1CbsOJK1kwzpDbY9fpKbsW AWVc1pdkH4PXngYJDXqvSvmyMfc= X-Mailgun-Sending-Ip: 104.130.122.25 X-Mailgun-Sid: WyJlNmU5NiIsICJsaW51eC1zY3NpQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5e2b325d.7efdc3f4bb90-smtp-out-n01; Fri, 24 Jan 2020 18:07:25 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id D62C1C4479C; Fri, 24 Jan 2020 18:07:24 +0000 (UTC) Received: from [10.46.161.159] (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: asutoshd) by smtp.codeaurora.org (Postfix) with ESMTPSA id 7A00DC433A2; Fri, 24 Jan 2020 18:07:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 7A00DC433A2 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=asutoshd@codeaurora.org Subject: Re: [PATCH v4 5/8] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic To: Can Guo , nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com Cc: Alim Akhtar , Avri Altman , Pedro Sousa , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Venkat Gopalakrishnan , Tomas Winkler , open list References: <1579764349-15578-1-git-send-email-cang@codeaurora.org> <1579764349-15578-6-git-send-email-cang@codeaurora.org> From: "Asutosh Das (asd)" Message-ID: <4aaf60bc-b398-67a1-7ed5-e0571f30bc95@codeaurora.org> Date: Fri, 24 Jan 2020 10:07:23 -0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <1579764349-15578-6-git-send-email-cang@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 1/22/2020 11:25 PM, Can Guo wrote: > The async version of ufshcd_hold(async == true), which is only called > in queuecommand path as for now, is expected to work in atomic context, > thus it should not sleep or schedule out. When it runs into the condition > that clocks are ON but link is still in hibern8 state, it should bail out > without flushing the clock ungate work. > > Signed-off-by: Can Guo > Reviewed-by: Hongwu Su > --- Reviewed-by: Asutosh Das > drivers/scsi/ufs/ufshcd.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c > index 4dfd705..c316a07 100644 > --- a/drivers/scsi/ufs/ufshcd.c > +++ b/drivers/scsi/ufs/ufshcd.c > @@ -1542,6 +1542,11 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) > */ > if (ufshcd_can_hibern8_during_gating(hba) && > ufshcd_is_link_hibern8(hba)) { > + if (async) { > + rc = -EAGAIN; > + hba->clk_gating.active_reqs--; > + break; > + } > spin_unlock_irqrestore(hba->host->host_lock, flags); > flush_work(&hba->clk_gating.ungate_work); > spin_lock_irqsave(hba->host->host_lock, flags); > -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, Linux Foundation Collaborative Project