From patchwork Mon May 24 08:47:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 12275685 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 CF917C47080 for ; Mon, 24 May 2021 08:48:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6B2061153 for ; Mon, 24 May 2021 08:48:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232543AbhEXIte (ORCPT ); Mon, 24 May 2021 04:49:34 -0400 Received: from labrats.qualcomm.com ([199.106.110.90]:6211 "EHLO labrats.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232513AbhEXIt1 (ORCPT ); Mon, 24 May 2021 04:49:27 -0400 IronPort-SDR: FUOsR8lCnOZeWBw9JWra+xI6PrOJeDIRIZrauHuLV7pMuON3fNYa9k1TpbBxVrv8Ux7IvA7eOY 6+qeIFgtapaveu1pYt4W4n7ojasfA1BKxeRT/OZSeOY121Sp1mMzfWXkIKZFtHyw/8fRd43AFT yTWFVw9bdlvz0LsADXUr7hBm2xHQV8a4sEHuQfi9suoAkBdoTsGdQwGTo3oIAh0RxW1wUJnQki wMCGSwbtF3/Q0TVbSha/tEIqip0idrvIJ4NOSWHxnMl9+Vs+PgTojwZsJBK6LxpXxhnuYL2cyM vPg= X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="47877522" Received: from unknown (HELO ironmsg04-sd.qualcomm.com) ([10.53.140.144]) by labrats.qualcomm.com with ESMTP; 24 May 2021 01:47:56 -0700 X-QCInternal: smtphost Received: from stor-presley.qualcomm.com ([192.168.140.85]) by ironmsg04-sd.qualcomm.com with ESMTP; 24 May 2021 01:47:55 -0700 Received: by stor-presley.qualcomm.com (Postfix, from userid 359480) id 3CBE221AD7; Mon, 24 May 2021 01:47:55 -0700 (PDT) From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, cang@codeaurora.org Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Jaegeuk Kim , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 6/6] scsi: ufs: Update the fast abort path in ufshcd_abort() for PM requests Date: Mon, 24 May 2021 01:47:25 -0700 Message-Id: <1621846046-22204-7-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1621846046-22204-1-git-send-email-cang@codeaurora.org> References: <1621846046-22204-1-git-send-email-cang@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org If PM requests fail during runtime suspend/resume, RPM framework saves the error to dev->power.runtime_error. Before the runtime_error gets cleared, runtime PM on this specific device won't work again, leaving the device in either suspended or active state permanently. When task abort happens to a PM request sent during runtime suspend/resume, even if it can be successfully aborted, RPM framework anyways saves the (TIMEOUT) error. But we want more and we can do better - let error handling recover and clear the runtime_error. So, let PM requests take the fast abort path in ufshcd_abort(). Signed-off-by: Can Guo --- drivers/scsi/ufs/ufshcd.c | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 9a3bc04..8312b31 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -2731,7 +2731,7 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) * err handler blocked for too long. So, just fail the scsi cmd * sent from PM ops, err handler can recover PM error anyways. */ - if (hba->wl_pm_op_in_progress) { + if (cmd->request->rq_flags & RQF_PM) { hba->force_reset = true; set_host_byte(cmd, DID_BAD_TARGET); cmd->scsi_done(cmd); @@ -2764,7 +2764,7 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) (hba->clk_gating.state != CLKS_ON)); if (unlikely(test_bit(tag, &hba->outstanding_reqs))) { - if (hba->wl_pm_op_in_progress) + if (cmd->request->rq_flags & RQF_PM) set_host_byte(cmd, DID_BAD_TARGET); else err = SCSI_MLQUEUE_HOST_BUSY; @@ -6982,11 +6982,14 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) int err = 0; struct ufshcd_lrb *lrbp; u32 reg; + bool need_eh = false; host = cmd->device->host; hba = shost_priv(host); tag = cmd->request->tag; lrbp = &hba->lrb[tag]; + + dev_info(hba->dev, "%s: Device abort task at tag %d\n", __func__, tag); if (!ufshcd_valid_tag(hba, tag)) { dev_err(hba->dev, "%s: invalid command tag %d: cmd=0x%p, cmd->request=0x%p", @@ -7004,9 +7007,6 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) goto out; } - /* Print Transfer Request of aborted task */ - dev_info(hba->dev, "%s: Device abort task at tag %d\n", __func__, tag); - /* * Print detailed info about aborted request. * As more than one request might get aborted at the same time, @@ -7034,21 +7034,21 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) } /* - * Task abort to the device W-LUN is illegal. When this command - * will fail, due to spec violation, scsi err handling next step - * will be to send LU reset which, again, is a spec violation. - * To avoid these unnecessary/illegal steps, first we clean up - * the lrb taken by this cmd and re-set it in outstanding_reqs, - * then queue the eh_work and bail. + * This fast path guarantees the cmd always gets aborted successfully, + * meanwhile it invokes the error handler. It allows contexts, which + * are blocked by this cmd, to fail fast. It serves multiple purposes: + * #1 To avoid unnecessary/illagal abort attempts to the W-LU. + * #2 To avoid live lock between eh_work and specific contexts, i.e., + * suspend/resume and eh_work itself. + * #3 To let eh_work recover runtime PM error in case abort happens + * to cmds sent from runtime suspend/resume ops. */ - if (lrbp->lun == UFS_UPIU_UFS_DEVICE_WLUN) { + if (lrbp->lun == UFS_UPIU_UFS_DEVICE_WLUN || + (cmd->request->rq_flags & RQF_PM)) { ufshcd_update_evt_hist(hba, UFS_EVT_ABORT, lrbp->lun); __ufshcd_transfer_req_compl(hba, (1UL << tag)); set_bit(tag, &hba->outstanding_reqs); - spin_lock_irqsave(host->host_lock, flags); - hba->force_reset = true; - ufshcd_schedule_eh_work(hba); - spin_unlock_irqrestore(host->host_lock, flags); + need_eh = true; goto out; } @@ -7062,6 +7062,12 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) cleanup: __ufshcd_transfer_req_compl(hba, (1UL << tag)); out: + if (cmd->request->rq_flags & RQF_PM || need_eh) { + spin_lock_irqsave(host->host_lock, flags); + hba->force_reset = true; + ufshcd_schedule_eh_work(hba); + spin_unlock_irqrestore(host->host_lock, flags); + } err = SUCCESS; } else { dev_err(hba->dev, "%s: failed with err %d\n", __func__, err);