From patchwork Fri Nov 20 16:35:23 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 7669891 Return-Path: X-Original-To: patchwork-linux-block@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 58E32BF90C for ; Fri, 20 Nov 2015 16:42:08 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 788BF20458 for ; Fri, 20 Nov 2015 16:42:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 78F3B20384 for ; Fri, 20 Nov 2015 16:42:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162537AbbKTQmG (ORCPT ); Fri, 20 Nov 2015 11:42:06 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:54646 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1162440AbbKTQmF (ORCPT ); Fri, 20 Nov 2015 11:42:05 -0500 Received: from p3ee3e1bb.dip0.t-ipconnect.de ([62.227.225.187] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zzol8-0008KL-4s; Fri, 20 Nov 2015 16:42:02 +0000 From: Christoph Hellwig To: keith.busch@intel.com, axboe@fb.com Cc: linux-nvme@lists.infradead.org, linux-block@vger.kernel.org Subject: [PATCH 28/47] nvme: simplify resets Date: Fri, 20 Nov 2015 17:35:23 +0100 Message-Id: <1448037342-18384-29-git-send-email-hch@lst.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1448037342-18384-1-git-send-email-hch@lst.de> References: <1448037342-18384-1-git-send-email-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Don't delete the controller from dev_list before queuing a reset, instead just check for it being reset in the polling kthread. This allows to remove the dev_list_lock in various places, and in addition we can simply rely on checking the queue_work return value to see if we could reset a controller. Signed-off-by: Christoph Hellwig Signed-off-by: Keith Busch --- drivers/nvme/host/pci.c | 39 +++++++++++++-------------------------- 1 file changed, 13 insertions(+), 26 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 9a6e47e..3173f0c 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -76,7 +76,6 @@ static wait_queue_head_t nvme_kthread_wait; struct nvme_dev; struct nvme_queue; -static int __nvme_reset(struct nvme_dev *dev); static int nvme_reset(struct nvme_dev *dev); static void nvme_process_cq(struct nvme_queue *nvmeq); static void nvme_dead_ctrl(struct nvme_dev *dev); @@ -1085,13 +1084,11 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved) * the admin queue. */ if (!nvmeq->qid || cmd_rq->aborted) { - spin_lock_irq(&dev_list_lock); - if (!__nvme_reset(dev)) { + if (queue_work(nvme_workq, &dev->reset_work)) { dev_warn(dev->dev, "I/O %d QID %d timeout, reset controller\n", req->tag, nvmeq->qid); } - spin_unlock_irq(&dev_list_lock); /* * Mark the request as quiesced, that is don't do anything with @@ -1589,9 +1586,15 @@ static int nvme_kthread(void *data) int i; u32 csts = readl(dev->bar + NVME_REG_CSTS); + /* + * Skip controllers currently under reset. + */ + if (work_pending(&dev->reset_work) || work_busy(&dev->reset_work)) + continue; + if ((dev->subsystem && (csts & NVME_CSTS_NSSRO)) || csts & NVME_CSTS_CFS) { - if (!__nvme_reset(dev)) { + if (queue_work(nvme_workq, &dev->reset_work)) { dev_warn(dev->dev, "Failed status: %x, reset controller\n", readl(dev->bar + NVME_REG_CSTS)); @@ -2318,33 +2321,17 @@ static void nvme_reset_work(struct work_struct *ws) schedule_work(&dev->probe_work); } -static int __nvme_reset(struct nvme_dev *dev) -{ - if (work_pending(&dev->reset_work)) - return -EBUSY; - list_del_init(&dev->node); - queue_work(nvme_workq, &dev->reset_work); - return 0; -} - static int nvme_reset(struct nvme_dev *dev) { - int ret; - if (!dev->ctrl.admin_q || blk_queue_dying(dev->ctrl.admin_q)) return -ENODEV; - spin_lock(&dev_list_lock); - ret = __nvme_reset(dev); - spin_unlock(&dev_list_lock); - - if (!ret) { - flush_work(&dev->reset_work); - flush_work(&dev->probe_work); - return 0; - } + if (!queue_work(nvme_workq, &dev->reset_work)) + return -EBUSY; - return ret; + flush_work(&dev->reset_work); + flush_work(&dev->probe_work); + return 0; } static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)