From patchwork Wed May 6 04:55:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11530193 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B0B26912 for ; Wed, 6 May 2020 04:56:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 854F4206F9 for ; Wed, 6 May 2020 04:56:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="Qn6wzS3l" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725821AbgEFE4s (ORCPT ); Wed, 6 May 2020 00:56:48 -0400 Received: from mail26.static.mailgun.info ([104.130.122.26]:39908 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725796AbgEFE4r (ORCPT ); Wed, 6 May 2020 00:56:47 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1588741006; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=QX8Zhtt2ZI9PyrjDSVNOucmxgJDf+kNLava4CsP69mA=; b=Qn6wzS3lJaoKyONR9GX+4S5HkkXmnAFYhWCrT44/H5LjGBkWn/d2sEGYrYBHIKxNFghrE+I1 f4S28+6x/mWeJKga7wtVsXwQBYxgjQbGFM1Pr+45fr7AGdA6ml5bIbwYaViE+NfGraBV98p+ fDvCLMFjRTriOqWXjPD6LZ/kUyM= X-Mailgun-Sending-Ip: 104.130.122.26 X-Mailgun-Sid: WyJlNmU5NiIsICJsaW51eC1zY3NpQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 6DB40C44792; Wed, 6 May 2020 04:56:44 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=ALL_TRUSTED,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.0 Received: from pacamara-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id A6838C433D2; Wed, 6 May 2020 04:56:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org A6838C433D2 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=cang@codeaurora.org From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, stanley.chu@mediatek.com, alim.akhtar@samsung.com, beanhuo@micron.com, Avri.Altman@wdc.com, bjorn.andersson@linaro.org, bvanassche@acm.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: "James E.J. Bottomley" , "Martin K. Petersen" , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v4 1/1] scsi: pm: Balance pm_only counter of request queue during system resume Date: Tue, 5 May 2020 21:55:35 -0700 Message-Id: <1588740936-28846-1-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 2.7.4 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org During system resume, scsi_resume_device() decreases a request queue's pm_only counter if the scsi device was quiesced before. But after that, if the scsi device's RPM status is RPM_SUSPENDED, the pm_only counter is still held (non-zero). Current scsi resume hook only sets the RPM status of the scsi device and its request queue to RPM_ACTIVE, but leaves the pm_only counter unchanged. This may make the request queue's pm_only counter remain non-zero after resume hook returns, hence those who are waiting on the mq_freeze_wq would never be woken up. Fix this by calling blk_post_runtime_resume() if a sdev's RPM status was RPM_SUSPENDED. (struct request_queue)0xFFFFFF815B69E938 pm_only = (counter = 2), rpm_status = 0, dev = 0xFFFFFF815B0511A0, ((struct device)0xFFFFFF815B0511A0)).power is_suspended = FALSE, runtime_status = RPM_ACTIVE, (struct scsi_device)0xffffff815b051000 request_queue = 0xFFFFFF815B69E938, sdev_state = SDEV_RUNNING, quiesced_by = 0x0, B::v.f_/task_0xFFFFFF810C246940 -000|__switch_to(prev = 0xFFFFFF810C246940, next = 0xFFFFFF80A49357C0) -001|context_switch(inline) -001|__schedule(?) -002|schedule() -003|blk_queue_enter(q = 0xFFFFFF815B69E938, flags = 0) -004|generic_make_request(?) -005|submit_bio(bio = 0xFFFFFF80A8195B80) Signed-off-by: Can Guo Reviewed-by: Bart Van Assche --- Change since v3: - Instead of relying on pm_only counter, rely on the runtime status of a sdev. (Based on the discussion with Bart) Change since v2: - Rebased on 5.8-scsi-queue Change since v1: - Added more debugging context info drivers/scsi/scsi_pm.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c index 3717eea..5f0ad8b 100644 --- a/drivers/scsi/scsi_pm.c +++ b/drivers/scsi/scsi_pm.c @@ -80,6 +80,10 @@ static int scsi_dev_type_resume(struct device *dev, dev_dbg(dev, "scsi resume: %d\n", err); if (err == 0) { + bool was_runtime_suspended; + + was_runtime_suspended = pm_runtime_suspended(dev); + pm_runtime_disable(dev); err = pm_runtime_set_active(dev); pm_runtime_enable(dev); @@ -93,8 +97,10 @@ static int scsi_dev_type_resume(struct device *dev, */ if (!err && scsi_is_sdev_device(dev)) { struct scsi_device *sdev = to_scsi_device(dev); - - blk_set_runtime_active(sdev->request_queue); + if (was_runtime_suspended) + blk_post_runtime_resume(sdev->request_queue, 0); + else + blk_set_runtime_active(sdev->request_queue); } }