From patchwork Wed Nov 6 01:06:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 11229035 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 5E03E139A for ; Wed, 6 Nov 2019 01:06:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 159D42087E for ; Wed, 6 Nov 2019 01:06:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729882AbfKFBGi (ORCPT ); Tue, 5 Nov 2019 20:06:38 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:35746 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729614AbfKFBGh (ORCPT ); Tue, 5 Nov 2019 20:06:37 -0500 Received: by mail-pf1-f195.google.com with SMTP id d13so17503746pfq.2 for ; Tue, 05 Nov 2019 17:06:37 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=SjnXDIXMWyaEZe0+qjlI5Hw8rwsm/tA/fKJ5+QR6JlY=; b=i54jVRpgZBweaLKKsE7z8oU0tmertdS9Xm7pyHVPrZQ/5+xM9ejPGFs8azX0K/iqRW xM8Rolj6M7UbS/Qv439Wd1klAF3/rir2Oyf3txH1Ux4tDyz4MVBWCh3+ZGtR83cFBIFC r1GgOSvRgIZli3p8jSzMYYGNZg7MlZps5s8kLVOLg84u0nnmvnpxek1F8D0Kl8aMsWS/ cgwsLY1WFDt2p25RcwMNQFG6evVLe9Eu+R28eU4a9lgRGtFcimoOELROL4QWWUvk5XIe W5n6EXACgWkJZ42dTppMHV4VjMXsBH3nnyaRDYP9tRm5hr2iKzc3P7WUljmjO5NFehsQ eSyA== X-Gm-Message-State: APjAAAV/br6Vh+evIaVwE80digwWi6nFum14T9f4e1O/ynHsMh4O+gxX QqEUq6W78PwsB/yVBBik63rJzeNh X-Google-Smtp-Source: APXvYqymIwfR7wy4cXFF+aA0zqU+yrTyd9a2DL9h+Gm3t1TbBkJ4zurFiVR8iMD2BnsMLCLWX3P2EA== X-Received: by 2002:a62:1551:: with SMTP id 78mr39628047pfv.200.1573002396829; Tue, 05 Nov 2019 17:06:36 -0800 (PST) Received: from desktop-bart.svl.corp.google.com ([2620:15c:2cd:202:4308:52a3:24b6:2c60]) by smtp.gmail.com with ESMTPSA id j22sm18711443pff.42.2019.11.05.17.06.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 Nov 2019 17:06:36 -0800 (PST) From: Bart Van Assche To: Avri Altman , Bean Huo Cc: "Martin K . Petersen" , "James E . J . Bottomley" , linux-scsi@vger.kernel.org, Christoph Hellwig , Bart Van Assche , Yaniv Gardi , Stanley Chu , Tomas Winkler Subject: [PATCH RFC v3 1/3] ufs: Avoid busy-waiting by eliminating tag conflicts Date: Tue, 5 Nov 2019 17:06:26 -0800 Message-Id: <20191106010628.98180-2-bvanassche@acm.org> X-Mailer: git-send-email 2.24.0.rc1.363.gb1bccd3e3d-goog In-Reply-To: <20191106010628.98180-1-bvanassche@acm.org> References: <20191106010628.98180-1-bvanassche@acm.org> MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Instead of tracking which tags are in use in the ufs_hba.lrb_in_use bitmask, rely on the block layer tag allocation mechanism. This patch removes the following busy-waiting loop if ufshcd_issue_devman_upiu_cmd() and the block layer accidentally allocate the same tag for a SCSI request: * ufshcd_queuecommand() returns SCSI_MLQUEUE_HOST_BUSY. * The SCSI core requeues the SCSI command. Cc: Yaniv Gardi Cc: Stanley Chu Cc: Avri Altman Cc: Tomas Winkler Signed-off-by: Bart Van Assche Tested-by: Bean Huo --- drivers/scsi/ufs/ufshcd.c | 121 +++++++++++++++----------------------- drivers/scsi/ufs/ufshcd.h | 6 +- 2 files changed, 50 insertions(+), 77 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index c480a97943bd..4c8362a47577 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -497,8 +497,8 @@ static void ufshcd_print_tmrs(struct ufs_hba *hba, unsigned long bitmap) static void ufshcd_print_host_state(struct ufs_hba *hba) { dev_err(hba->dev, "UFS Host state=%d\n", hba->ufshcd_state); - dev_err(hba->dev, "lrb in use=0x%lx, outstanding reqs=0x%lx tasks=0x%lx\n", - hba->lrb_in_use, hba->outstanding_reqs, hba->outstanding_tasks); + dev_err(hba->dev, "outstanding reqs=0x%lx tasks=0x%lx\n", + hba->outstanding_reqs, hba->outstanding_tasks); dev_err(hba->dev, "saved_err=0x%x, saved_uic_err=0x%x\n", hba->saved_err, hba->saved_uic_err); dev_err(hba->dev, "Device power mode=%d, UIC link state=%d\n", @@ -1596,6 +1596,25 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) } EXPORT_SYMBOL_GPL(ufshcd_hold); +static bool ufshcd_is_busy(struct request *req, void *priv, bool reserved) +{ + int *busy = priv; + + WARN_ON_ONCE(reserved); + (*busy)++; + return false; +} + +/* Whether or not any tag is in use by a request that is in progress. */ +static bool ufshcd_any_tag_in_use(struct ufs_hba *hba) +{ + struct request_queue *q = hba->cmd_queue; + int busy = 0; + + blk_mq_tagset_busy_iter(q->tag_set, ufshcd_is_busy, &busy); + return busy; +} + static void ufshcd_gate_work(struct work_struct *work) { struct ufs_hba *hba = container_of(work, struct ufs_hba, @@ -1619,7 +1638,7 @@ static void ufshcd_gate_work(struct work_struct *work) if (hba->clk_gating.active_reqs || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL - || hba->lrb_in_use || hba->outstanding_tasks + || ufshcd_any_tag_in_use(hba) || hba->outstanding_tasks || hba->active_uic_cmd || hba->uic_async_done) goto rel_lock; @@ -1673,7 +1692,7 @@ static void __ufshcd_release(struct ufs_hba *hba) if (hba->clk_gating.active_reqs || hba->clk_gating.is_suspended || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL - || hba->lrb_in_use || hba->outstanding_tasks + || ufshcd_any_tag_in_use(hba) || hba->outstanding_tasks || hba->active_uic_cmd || hba->uic_async_done || ufshcd_eh_in_progress(hba)) return; @@ -2443,22 +2462,9 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) hba->req_abort_count = 0; - /* acquire the tag to make sure device cmds don't use it */ - if (test_and_set_bit_lock(tag, &hba->lrb_in_use)) { - /* - * Dev manage command in progress, requeue the command. - * Requeuing the command helps in cases where the request *may* - * find different tag instead of waiting for dev manage command - * completion. - */ - err = SCSI_MLQUEUE_HOST_BUSY; - goto out; - } - err = ufshcd_hold(hba, true); if (err) { err = SCSI_MLQUEUE_HOST_BUSY; - clear_bit_unlock(tag, &hba->lrb_in_use); goto out; } WARN_ON(hba->clk_gating.state != CLKS_ON); @@ -2479,7 +2485,6 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) err = ufshcd_map_sg(hba, lrbp); if (err) { lrbp->cmd = NULL; - clear_bit_unlock(tag, &hba->lrb_in_use); goto out; } /* Make sure descriptors are ready before ringing the doorbell */ @@ -2625,44 +2630,6 @@ static int ufshcd_wait_for_dev_cmd(struct ufs_hba *hba, return err; } -/** - * ufshcd_get_dev_cmd_tag - Get device management command tag - * @hba: per-adapter instance - * @tag_out: pointer to variable with available slot value - * - * Get a free slot and lock it until device management command - * completes. - * - * Returns false if free slot is unavailable for locking, else - * return true with tag value in @tag. - */ -static bool ufshcd_get_dev_cmd_tag(struct ufs_hba *hba, int *tag_out) -{ - int tag; - bool ret = false; - unsigned long tmp; - - if (!tag_out) - goto out; - - do { - tmp = ~hba->lrb_in_use; - tag = find_last_bit(&tmp, hba->nutrs); - if (tag >= hba->nutrs) - goto out; - } while (test_and_set_bit_lock(tag, &hba->lrb_in_use)); - - *tag_out = tag; - ret = true; -out: - return ret; -} - -static inline void ufshcd_put_dev_cmd_tag(struct ufs_hba *hba, int tag) -{ - clear_bit_unlock(tag, &hba->lrb_in_use); -} - /** * ufshcd_exec_dev_cmd - API for sending device management requests * @hba: UFS hba @@ -2675,6 +2642,8 @@ static inline void ufshcd_put_dev_cmd_tag(struct ufs_hba *hba, int tag) static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, enum dev_cmd_type cmd_type, int timeout) { + struct request_queue *q = hba->cmd_queue; + struct request *req; struct ufshcd_lrb *lrbp; int err; int tag; @@ -2688,7 +2657,11 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, * Even though we use wait_event() which sleeps indefinitely, * the maximum wait time is bounded by SCSI request timeout. */ - wait_event(hba->dev_cmd.tag_wq, ufshcd_get_dev_cmd_tag(hba, &tag)); + req = blk_get_request(q, REQ_OP_DRV_OUT, 0); + if (IS_ERR(req)) + return PTR_ERR(req); + tag = req->tag; + WARN_ON_ONCE(!ufshcd_valid_tag(hba, tag)); init_completion(&wait); lrbp = &hba->lrb[tag]; @@ -2712,8 +2685,7 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, err ? "query_complete_err" : "query_complete"); out_put_tag: - ufshcd_put_dev_cmd_tag(hba, tag); - wake_up(&hba->dev_cmd.tag_wq); + blk_put_request(req); up_read(&hba->clk_scaling_lock); return err; } @@ -4832,7 +4804,6 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba, cmd->result = result; /* Mark completed command as NULL in LRB */ lrbp->cmd = NULL; - clear_bit_unlock(index, &hba->lrb_in_use); /* Do not touch lrbp after scsi done */ cmd->scsi_done(cmd); __ufshcd_release(hba); @@ -4854,9 +4825,6 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba, hba->outstanding_reqs ^= completed_reqs; ufshcd_clk_scaling_update_busy(hba); - - /* we might have free'd some tags above */ - wake_up(&hba->dev_cmd.tag_wq); } /** @@ -5785,6 +5753,8 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, enum dev_cmd_type cmd_type, enum query_opcode desc_op) { + struct request_queue *q = hba->cmd_queue; + struct request *req; struct ufshcd_lrb *lrbp; int err = 0; int tag; @@ -5794,7 +5764,11 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, down_read(&hba->clk_scaling_lock); - wait_event(hba->dev_cmd.tag_wq, ufshcd_get_dev_cmd_tag(hba, &tag)); + req = blk_get_request(q, REQ_OP_DRV_OUT, 0); + if (IS_ERR(req)) + return PTR_ERR(req); + tag = req->tag; + WARN_ON_ONCE(!ufshcd_valid_tag(hba, tag)); init_completion(&wait); lrbp = &hba->lrb[tag]; @@ -5868,8 +5842,7 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, } } - ufshcd_put_dev_cmd_tag(hba, tag); - wake_up(&hba->dev_cmd.tag_wq); + blk_put_request(req); up_read(&hba->clk_scaling_lock); return err; } @@ -6164,9 +6137,6 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) hba->lrb[tag].cmd = NULL; spin_unlock_irqrestore(host->host_lock, flags); - clear_bit_unlock(tag, &hba->lrb_in_use); - wake_up(&hba->dev_cmd.tag_wq); - out: if (!err) { err = SUCCESS; @@ -8170,6 +8140,7 @@ void ufshcd_remove(struct ufs_hba *hba) { ufs_bsg_remove(hba); ufs_sysfs_remove_nodes(hba->dev); + blk_cleanup_queue(hba->cmd_queue); scsi_remove_host(hba->host); /* disable interrupts */ ufshcd_disable_intr(hba, hba->intr_mask); @@ -8333,9 +8304,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) init_rwsem(&hba->clk_scaling_lock); - /* Initialize device management tag acquire wait queue */ - init_waitqueue_head(&hba->dev_cmd.tag_wq); - ufshcd_init_clk_gating(hba); ufshcd_init_clk_scaling(hba); @@ -8369,6 +8337,11 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) goto exit_gating; } + err = -ENOMEM; + hba->cmd_queue = blk_mq_init_queue(&hba->host->tag_set); + if (!hba->cmd_queue) + goto out_remove_scsi_host; + /* Reset the attached device */ ufshcd_vops_device_reset(hba); @@ -8378,7 +8351,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) dev_err(hba->dev, "Host controller enable failed\n"); ufshcd_print_host_regs(hba); ufshcd_print_host_state(hba); - goto out_remove_scsi_host; + goto free_cmd_queue; } /* @@ -8415,6 +8388,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) return 0; +free_cmd_queue: + blk_cleanup_queue(hba->cmd_queue); out_remove_scsi_host: scsi_remove_host(hba->host); exit_gating: diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index e3593cce23c1..9707194fa4b7 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -212,13 +212,11 @@ struct ufs_query { * @type: device management command type - Query, NOP OUT * @lock: lock to allow one command at a time * @complete: internal commands completion - * @tag_wq: wait queue until free command slot is available */ struct ufs_dev_cmd { enum dev_cmd_type type; struct mutex lock; struct completion *complete; - wait_queue_head_t tag_wq; struct ufs_query query; }; @@ -480,7 +478,7 @@ struct ufs_stats { * @host: Scsi_Host instance of the driver * @dev: device handle * @lrb: local reference block - * @lrb_in_use: lrb in use + * @cmd_queue: Used to allocate command tags from hba->host->tag_set. * @outstanding_tasks: Bits representing outstanding task requests * @outstanding_reqs: Bits representing outstanding transfer requests * @capabilities: UFS Controller Capabilities @@ -538,6 +536,7 @@ struct ufs_hba { struct Scsi_Host *host; struct device *dev; + struct request_queue *cmd_queue; /* * This field is to keep a reference to "scsi_device" corresponding to * "UFS device" W-LU. @@ -558,7 +557,6 @@ struct ufs_hba { u32 ahit; struct ufshcd_lrb *lrb; - unsigned long lrb_in_use; unsigned long outstanding_tasks; unsigned long outstanding_reqs; From patchwork Wed Nov 6 01:06:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 11229037 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 59907112B for ; Wed, 6 Nov 2019 01:06:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 24B082087E for ; Wed, 6 Nov 2019 01:06:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730125AbfKFBGl (ORCPT ); Tue, 5 Nov 2019 20:06:41 -0500 Received: from mail-pl1-f196.google.com ([209.85.214.196]:41409 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729614AbfKFBGk (ORCPT ); Tue, 5 Nov 2019 20:06:40 -0500 Received: by mail-pl1-f196.google.com with SMTP id d29so4240909plj.8 for ; Tue, 05 Nov 2019 17:06:38 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Wzc2lyE50dXLATIvUz2BRn1O95QbHhYiIXfX2SjRwcA=; b=cRooUp7BgjZlBW24/CwrYy6J+aBpGsRImVxmClAHTqd2+txo3mq63SHg1mzOFxgBW6 /FG1NKcQORG/wp6LpeGk0NjrYwRIWZiBSlcybfe9PGb8A+eP0qKgED3wEWCR9p4WTRe2 FPrJU35XOaSZuSlMnlUsk6Ff62d6pXZOBjEPRlB2YKYz2WT+FDRwHjl9g+zgRy2LQurI 2KgxPrTvRWUBQ5Sl+xHPTRUaPHdm4B3s+cE/eUHXLUL67bHO3XAtrpDW/MwGwTEtFEzA uhrvgPooeIGKVQS21n3EXjeyauuXJ3p5noD7k4Q25Xt2qXnre9VuvEeiFEzjrgDLVB2A VR4Q== X-Gm-Message-State: APjAAAXVwRdOT9o3mnF0ZQ6IZNAm9z+Y5uLaXWLSo8yjgmMV+s99aD57 CWmJFvk8JzvAVgOaJiJf+EI= X-Google-Smtp-Source: APXvYqzbDqjgTqyW8BcOn+xid63i/jsEBAXVmPBVMIbBl8tRnmT2Dt6qYDb02OWDiBE3ORDoRPnkNA== X-Received: by 2002:a17:902:44d:: with SMTP id 71mr34580457ple.274.1573002398069; Tue, 05 Nov 2019 17:06:38 -0800 (PST) Received: from desktop-bart.svl.corp.google.com ([2620:15c:2cd:202:4308:52a3:24b6:2c60]) by smtp.gmail.com with ESMTPSA id j22sm18711443pff.42.2019.11.05.17.06.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 Nov 2019 17:06:37 -0800 (PST) From: Bart Van Assche To: Avri Altman , Bean Huo Cc: "Martin K . Petersen" , "James E . J . Bottomley" , linux-scsi@vger.kernel.org, Christoph Hellwig , Bart Van Assche , Yaniv Gardi , Stanley Chu , Tomas Winkler Subject: [PATCH RFC v3 2/3] ufs: Use blk_{get,put}_request() to allocate and free TMFs Date: Tue, 5 Nov 2019 17:06:27 -0800 Message-Id: <20191106010628.98180-3-bvanassche@acm.org> X-Mailer: git-send-email 2.24.0.rc1.363.gb1bccd3e3d-goog In-Reply-To: <20191106010628.98180-1-bvanassche@acm.org> References: <20191106010628.98180-1-bvanassche@acm.org> MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Manage TMF tags with blk_{get,put}_request() instead of ufshcd_get_tm_free_slot() / ufshcd_put_tm_slot(). Store a per-request completion pointer in request.end_io_data instead of using a waitqueue to report TMF completion. Cc: Yaniv Gardi Cc: Stanley Chu Cc: Avri Altman Cc: Tomas Winkler Signed-off-by: Bart Van Assche Tested-by: Bean Huo --- drivers/scsi/ufs/ufshcd.c | 122 +++++++++++++++++++++++--------------- drivers/scsi/ufs/ufshcd.h | 12 ++-- 2 files changed, 77 insertions(+), 57 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 4c8362a47577..2c6300fd5c75 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -645,40 +645,6 @@ static inline int ufshcd_get_tr_ocs(struct ufshcd_lrb *lrbp) return le32_to_cpu(lrbp->utr_descriptor_ptr->header.dword_2) & MASK_OCS; } -/** - * ufshcd_get_tm_free_slot - get a free slot for task management request - * @hba: per adapter instance - * @free_slot: pointer to variable with available slot value - * - * Get a free tag and lock it until ufshcd_put_tm_slot() is called. - * Returns 0 if free slot is not available, else return 1 with tag value - * in @free_slot. - */ -static bool ufshcd_get_tm_free_slot(struct ufs_hba *hba, int *free_slot) -{ - int tag; - bool ret = false; - - if (!free_slot) - goto out; - - do { - tag = find_first_zero_bit(&hba->tm_slots_in_use, hba->nutmrs); - if (tag >= hba->nutmrs) - goto out; - } while (test_and_set_bit_lock(tag, &hba->tm_slots_in_use)); - - *free_slot = tag; - ret = true; -out: - return ret; -} - -static inline void ufshcd_put_tm_slot(struct ufs_hba *hba, int slot) -{ - clear_bit_unlock(slot, &hba->tm_slots_in_use); -} - /** * ufshcd_utrl_clear - Clear a bit in UTRLCLR register * @hba: per adapter instance @@ -5515,17 +5481,38 @@ static void ufshcd_check_errors(struct ufs_hba *hba) */ } +struct ctm_info { + struct ufs_hba *hba; + unsigned long pending; +}; + +static bool ufshcd_compl_tm(struct request *req, void *priv, bool reserved) +{ + const struct ctm_info *const ci = priv; + struct completion *c; + + WARN_ON_ONCE(reserved); + if (test_bit(req->tag, &ci->pending)) + return true; + c = req->end_io_data; + if (c) + complete(c); + return true; +} + /** * ufshcd_tmc_handler - handle task management function completion * @hba: per adapter instance */ static void ufshcd_tmc_handler(struct ufs_hba *hba) { - u32 tm_doorbell; + struct request_queue *q = hba->tmf_queue; + struct ctm_info ci = { + .hba = hba, + .pending = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL), + }; - tm_doorbell = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL); - hba->tm_condition = tm_doorbell ^ hba->outstanding_tasks; - wake_up(&hba->tm_wq); + blk_mq_tagset_busy_iter(q->tag_set, ufshcd_compl_tm, &ci); } /** @@ -5618,7 +5605,10 @@ static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag) static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, struct utp_task_req_desc *treq, u8 tm_function) { + struct request_queue *q = hba->tmf_queue; struct Scsi_Host *host = hba->host; + DECLARE_COMPLETION_ONSTACK(wait); + struct request *req; unsigned long flags; int free_slot, task_tag, err; @@ -5627,7 +5617,10 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, * Even though we use wait_event() which sleeps indefinitely, * the maximum wait time is bounded by %TM_CMD_TIMEOUT. */ - wait_event(hba->tm_tag_wq, ufshcd_get_tm_free_slot(hba, &free_slot)); + req = blk_get_request(q, REQ_OP_DRV_OUT, BLK_MQ_REQ_RESERVED); + req->end_io_data = &wait; + free_slot = req->tag; + WARN_ON_ONCE(free_slot < 0 || free_slot >= hba->nutmrs); ufshcd_hold(hba, false); spin_lock_irqsave(host->host_lock, flags); @@ -5653,10 +5646,14 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, ufshcd_add_tm_upiu_trace(hba, task_tag, "tm_send"); /* wait until the task management command is completed */ - err = wait_event_timeout(hba->tm_wq, - test_bit(free_slot, &hba->tm_condition), + err = wait_for_completion_io_timeout(&wait, msecs_to_jiffies(TM_CMD_TIMEOUT)); if (!err) { + /* + * Make sure that ufshcd_compl_tm() does not trigger a + * use-after-free. + */ + req->end_io_data = NULL; ufshcd_add_tm_upiu_trace(hba, task_tag, "tm_complete_err"); dev_err(hba->dev, "%s: task management cmd 0x%.2x timed-out\n", __func__, tm_function); @@ -5675,9 +5672,7 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, __clear_bit(free_slot, &hba->outstanding_tasks); spin_unlock_irqrestore(hba->host->host_lock, flags); - clear_bit(free_slot, &hba->tm_condition); - ufshcd_put_tm_slot(hba, free_slot); - wake_up(&hba->tm_tag_wq); + blk_put_request(req); ufshcd_release(hba); return err; @@ -8140,6 +8135,8 @@ void ufshcd_remove(struct ufs_hba *hba) { ufs_bsg_remove(hba); ufs_sysfs_remove_nodes(hba->dev); + blk_cleanup_queue(hba->tmf_queue); + blk_mq_free_tag_set(&hba->tmf_tag_set); blk_cleanup_queue(hba->cmd_queue); scsi_remove_host(hba->host); /* disable interrupts */ @@ -8219,6 +8216,18 @@ int ufshcd_alloc_host(struct device *dev, struct ufs_hba **hba_handle) } EXPORT_SYMBOL(ufshcd_alloc_host); +/* This function exists because blk_mq_alloc_tag_set() requires this. */ +static blk_status_t ufshcd_queue_tmf(struct blk_mq_hw_ctx *hctx, + const struct blk_mq_queue_data *qd) +{ + WARN_ON_ONCE(true); + return BLK_STS_NOTSUPP; +} + +static const struct blk_mq_ops ufshcd_tmf_ops = { + .queue_rq = ufshcd_queue_tmf, +}; + /** * ufshcd_init - Driver initialization routine * @hba: per-adapter instance @@ -8288,10 +8297,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) hba->max_pwr_info.is_valid = false; - /* Initailize wait queue for task management */ - init_waitqueue_head(&hba->tm_wq); - init_waitqueue_head(&hba->tm_tag_wq); - /* Initialize work queues */ INIT_WORK(&hba->eh_work, ufshcd_err_handler); INIT_WORK(&hba->eeh_work, ufshcd_exception_event_handler); @@ -8342,6 +8347,21 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) if (!hba->cmd_queue) goto out_remove_scsi_host; + hba->tmf_tag_set = (struct blk_mq_tag_set) { + .nr_hw_queues = 1, + .queue_depth = hba->nutmrs, + .ops = &ufshcd_tmf_ops, + .flags = BLK_MQ_F_NO_SCHED, + }; + err = blk_mq_alloc_tag_set(&hba->tmf_tag_set); + if (err < 0) + goto free_cmd_queue; + hba->tmf_queue = blk_mq_init_queue(&hba->tmf_tag_set); + if (IS_ERR(hba->tmf_queue)) { + err = PTR_ERR(hba->tmf_queue); + goto free_tmf_tag_set; + } + /* Reset the attached device */ ufshcd_vops_device_reset(hba); @@ -8351,7 +8371,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) dev_err(hba->dev, "Host controller enable failed\n"); ufshcd_print_host_regs(hba); ufshcd_print_host_state(hba); - goto free_cmd_queue; + goto free_tmf_queue; } /* @@ -8388,6 +8408,10 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) return 0; +free_tmf_queue: + blk_cleanup_queue(hba->tmf_queue); +free_tmf_tag_set: + blk_mq_free_tag_set(&hba->tmf_tag_set); free_cmd_queue: blk_cleanup_queue(hba->cmd_queue); out_remove_scsi_host: diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 9707194fa4b7..6e0b87e8f875 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -490,11 +490,9 @@ struct ufs_stats { * @irq: Irq number of the controller * @active_uic_cmd: handle of active UIC command * @uic_cmd_mutex: mutex for uic command - * @tm_wq: wait queue for task management - * @tm_tag_wq: wait queue for free task management slots - * @tm_slots_in_use: bit map of task management request slots in use + * @tmf_tag_set: TMF tag set. + * @tmf_queue: Used to allocate TMF tags. * @pwr_done: completion for power mode change - * @tm_condition: condition variable for task management * @ufshcd_state: UFSHCD states * @eh_flags: Error handling flags * @intr_mask: Interrupt Mask Bits @@ -638,10 +636,8 @@ struct ufs_hba { /* Device deviations from standard UFS device spec. */ unsigned int dev_quirks; - wait_queue_head_t tm_wq; - wait_queue_head_t tm_tag_wq; - unsigned long tm_condition; - unsigned long tm_slots_in_use; + struct blk_mq_tag_set tmf_tag_set; + struct request_queue *tmf_queue; struct uic_command *active_uic_cmd; struct mutex uic_cmd_mutex; From patchwork Wed Nov 6 01:06:28 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 11229039 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 DA21F1864 for ; Wed, 6 Nov 2019 01:06:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4AFB2087E for ; Wed, 6 Nov 2019 01:06:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730231AbfKFBGl (ORCPT ); Tue, 5 Nov 2019 20:06:41 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:45292 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730022AbfKFBGl (ORCPT ); Tue, 5 Nov 2019 20:06:41 -0500 Received: by mail-pl1-f194.google.com with SMTP id y24so10590461plr.12 for ; Tue, 05 Nov 2019 17:06:40 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=K8uoHGEU8qp2Ur7la2QvEQBU55H4mx7lJu0v+B2JQqY=; b=AU/Fbo5ccLswApQ+MHxmF+QqCV1GGEqBrJdQHVhyt/hQaIOMXgE8AdpLHwE/j/Ro8l J6VRhpdcAqLI/SeY55oiWK6jcqnGLjfTJjprKbirHXngyasOA57CmRG2GZcw1BLi72gO o09mBUYT5VwhGHOwambzgNsQDPy1g/bsmORODBlnLyhEA+R0nf3dF+h7BDS2LDDy4Zpg P6eb4Pn32T8ZdVI1Nl84SGdLYz01ch7TznW/sSUUY7BLvDLvXd4xNovGFc+7/vNxm5cd 4wqZbe/yi9rfQAUy3qt5k5Z7adGN5V91K1F0e8orzVLvG9+/9AOe/iVZiQCEjhgbsvpv /ovA== X-Gm-Message-State: APjAAAWuuYy1HhpyDmsri2TI5CYEla4f9UXNyJf+cR3VFtBliyRBZgi+ YmSgTY6bcOkj5RRLxC+vZUc= X-Google-Smtp-Source: APXvYqyJ05v+4OM26RugCu257uuHopEWPKBClx/4sXOlMjrZjIJiHiX7nG5uTHuVOuc8rxLch6vYIQ== X-Received: by 2002:a17:902:8d98:: with SMTP id v24mr36018187plo.265.1573002399737; Tue, 05 Nov 2019 17:06:39 -0800 (PST) Received: from desktop-bart.svl.corp.google.com ([2620:15c:2cd:202:4308:52a3:24b6:2c60]) by smtp.gmail.com with ESMTPSA id j22sm18711443pff.42.2019.11.05.17.06.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 Nov 2019 17:06:38 -0800 (PST) From: Bart Van Assche To: Avri Altman , Bean Huo Cc: "Martin K . Petersen" , "James E . J . Bottomley" , linux-scsi@vger.kernel.org, Christoph Hellwig , Bart Van Assche , Yaniv Gardi , Stanley Chu , Tomas Winkler Subject: [PATCH RFC v3 3/3] ufs: Simplify the clock scaling mechanism implementation Date: Tue, 5 Nov 2019 17:06:28 -0800 Message-Id: <20191106010628.98180-4-bvanassche@acm.org> X-Mailer: git-send-email 2.24.0.rc1.363.gb1bccd3e3d-goog In-Reply-To: <20191106010628.98180-1-bvanassche@acm.org> References: <20191106010628.98180-1-bvanassche@acm.org> MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Scaling the clock is only safe while no commands are in progress. Use blk_mq_{un,}freeze_queue() to block submission of new commands and to wait for ongoing commands to complete. Cc: Yaniv Gardi Cc: Stanley Chu Cc: Avri Altman Cc: Tomas Winkler Signed-off-by: Bart Van Assche --- drivers/scsi/ufs/ufshcd.c | 134 ++++++++++++-------------------------- drivers/scsi/ufs/ufshcd.h | 3 - 2 files changed, 43 insertions(+), 94 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 2c6300fd5c75..d1912ba5d2d9 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -292,14 +292,49 @@ static inline void ufshcd_disable_irq(struct ufs_hba *hba) static void ufshcd_scsi_unblock_requests(struct ufs_hba *hba) { - if (atomic_dec_and_test(&hba->scsi_block_reqs_cnt)) - scsi_unblock_requests(hba->host); + struct scsi_device *sdev; + + blk_mq_unfreeze_queue(hba->tmf_queue); + blk_mq_unfreeze_queue(hba->cmd_queue); + shost_for_each_device(sdev, hba->host) + blk_mq_unfreeze_queue(sdev->request_queue); } -static void ufshcd_scsi_block_requests(struct ufs_hba *hba) +static int ufshcd_scsi_block_requests(struct ufs_hba *hba, + unsigned long timeout) { - if (atomic_inc_return(&hba->scsi_block_reqs_cnt) == 1) - scsi_block_requests(hba->host); + struct scsi_device *sdev; + unsigned long deadline = jiffies + timeout; + + if (timeout == ULONG_MAX) { + shost_for_each_device(sdev, hba->host) + blk_mq_freeze_queue(sdev->request_queue); + blk_mq_freeze_queue(hba->cmd_queue); + blk_mq_freeze_queue(hba->tmf_queue); + return 0; + } + + shost_for_each_device(sdev, hba->host) + blk_freeze_queue_start(sdev->request_queue); + blk_freeze_queue_start(hba->cmd_queue); + blk_freeze_queue_start(hba->tmf_queue); + shost_for_each_device(sdev, hba->host) { + if (blk_mq_freeze_queue_wait_timeout(sdev->request_queue, + max_t(long, 0, deadline - jiffies)) <= 0) { + goto err; + } + } + if (blk_mq_freeze_queue_wait_timeout(hba->cmd_queue, + max_t(long, 0, deadline - jiffies)) <= 0) + goto err; + if (blk_mq_freeze_queue_wait_timeout(hba->tmf_queue, + max_t(long, 0, deadline - jiffies)) <= 0) + goto err; + return 0; + +err: + ufshcd_scsi_unblock_requests(hba); + return -ETIMEDOUT; } static void ufshcd_add_cmd_upiu_trace(struct ufs_hba *hba, unsigned int tag, @@ -971,65 +1006,6 @@ static bool ufshcd_is_devfreq_scaling_required(struct ufs_hba *hba, return false; } -static int ufshcd_wait_for_doorbell_clr(struct ufs_hba *hba, - u64 wait_timeout_us) -{ - unsigned long flags; - int ret = 0; - u32 tm_doorbell; - u32 tr_doorbell; - bool timeout = false, do_last_check = false; - ktime_t start; - - ufshcd_hold(hba, false); - spin_lock_irqsave(hba->host->host_lock, flags); - /* - * Wait for all the outstanding tasks/transfer requests. - * Verify by checking the doorbell registers are clear. - */ - start = ktime_get(); - do { - if (hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) { - ret = -EBUSY; - goto out; - } - - tm_doorbell = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL); - tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL); - if (!tm_doorbell && !tr_doorbell) { - timeout = false; - break; - } else if (do_last_check) { - break; - } - - spin_unlock_irqrestore(hba->host->host_lock, flags); - schedule(); - if (ktime_to_us(ktime_sub(ktime_get(), start)) > - wait_timeout_us) { - timeout = true; - /* - * We might have scheduled out for long time so make - * sure to check if doorbells are cleared by this time - * or not. - */ - do_last_check = true; - } - spin_lock_irqsave(hba->host->host_lock, flags); - } while (tm_doorbell || tr_doorbell); - - if (timeout) { - dev_err(hba->dev, - "%s: timedout waiting for doorbell to clear (tm=0x%x, tr=0x%x)\n", - __func__, tm_doorbell, tr_doorbell); - ret = -EBUSY; - } -out: - spin_unlock_irqrestore(hba->host->host_lock, flags); - ufshcd_release(hba); - return ret; -} - /** * ufshcd_scale_gear - scale up/down UFS gear * @hba: per adapter instance @@ -1079,26 +1055,15 @@ static int ufshcd_scale_gear(struct ufs_hba *hba, bool scale_up) static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba) { - #define DOORBELL_CLR_TOUT_US (1000 * 1000) /* 1 sec */ - int ret = 0; /* * make sure that there are no outstanding requests when * clock scaling is in progress */ - ufshcd_scsi_block_requests(hba); - down_write(&hba->clk_scaling_lock); - if (ufshcd_wait_for_doorbell_clr(hba, DOORBELL_CLR_TOUT_US)) { - ret = -EBUSY; - up_write(&hba->clk_scaling_lock); - ufshcd_scsi_unblock_requests(hba); - } - - return ret; + return ufshcd_scsi_block_requests(hba, HZ); } static void ufshcd_clock_scaling_unprepare(struct ufs_hba *hba) { - up_write(&hba->clk_scaling_lock); ufshcd_scsi_unblock_requests(hba); } @@ -1528,7 +1493,7 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) */ /* fallthrough */ case CLKS_OFF: - ufshcd_scsi_block_requests(hba); + ufshcd_scsi_block_requests(hba, ULONG_MAX); hba->clk_gating.state = REQ_CLKS_ON; trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); @@ -2395,9 +2360,6 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) BUG(); } - if (!down_read_trylock(&hba->clk_scaling_lock)) - return SCSI_MLQUEUE_HOST_BUSY; - spin_lock_irqsave(hba->host->host_lock, flags); switch (hba->ufshcd_state) { case UFSHCD_STATE_OPERATIONAL: @@ -2462,7 +2424,6 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) out_unlock: spin_unlock_irqrestore(hba->host->host_lock, flags); out: - up_read(&hba->clk_scaling_lock); return err; } @@ -2616,8 +2577,6 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, struct completion wait; unsigned long flags; - down_read(&hba->clk_scaling_lock); - /* * Get free slot, sleep if slots are unavailable. * Even though we use wait_event() which sleeps indefinitely, @@ -2652,7 +2611,6 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, out_put_tag: blk_put_request(req); - up_read(&hba->clk_scaling_lock); return err; } @@ -5451,7 +5409,7 @@ static void ufshcd_check_errors(struct ufs_hba *hba) /* handle fatal errors only when link is functional */ if (hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL) { /* block commands from scsi mid-layer */ - ufshcd_scsi_block_requests(hba); + ufshcd_scsi_block_requests(hba, ULONG_MAX); hba->ufshcd_state = UFSHCD_STATE_EH_SCHEDULED; @@ -5757,8 +5715,6 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, unsigned long flags; u32 upiu_flags; - down_read(&hba->clk_scaling_lock); - req = blk_get_request(q, REQ_OP_DRV_OUT, 0); if (IS_ERR(req)) return PTR_ERR(req); @@ -5838,7 +5794,6 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, } blk_put_request(req); - up_read(&hba->clk_scaling_lock); return err; } @@ -8307,8 +8262,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) /* Initialize mutex for device management commands */ mutex_init(&hba->dev_cmd.lock); - init_rwsem(&hba->clk_scaling_lock); - ufshcd_init_clk_gating(hba); ufshcd_init_clk_scaling(hba); @@ -8394,7 +8347,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) /* Hold auto suspend until async scan completes */ pm_runtime_get_sync(dev); - atomic_set(&hba->scsi_block_reqs_cnt, 0); /* * We are assuming that device wasn't put in sleep/power-down * state exclusively during the boot stage before kernel. diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 6e0b87e8f875..cea71057fa90 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -517,7 +517,6 @@ struct ufs_stats { * @urgent_bkops_lvl: keeps track of urgent bkops level for device * @is_urgent_bkops_lvl_checked: keeps track if the urgent bkops level for * device is known or not. - * @scsi_block_reqs_cnt: reference counting for scsi block requests */ struct ufs_hba { void __iomem *mmio_base; @@ -721,9 +720,7 @@ struct ufs_hba { enum bkops_status urgent_bkops_lvl; bool is_urgent_bkops_lvl_checked; - struct rw_semaphore clk_scaling_lock; struct ufs_desc_size desc_size; - atomic_t scsi_block_reqs_cnt; struct device bsg_dev; struct request_queue *bsg_queue;