From 846cc05f95d599801f296d8599e82686ebd395f0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 26 Nov 2015 12:10:29 +0100 Subject: [PATCH] nvme: simplify resets 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 Signed-off-by: Jens Axboe --- 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 e683bd1a05e6..febcef5ae0aa 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -77,7 +77,6 @@ struct nvme_dev; struct nvme_queue; struct nvme_iod; -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_unmap_data(struct nvme_dev *dev, struct nvme_iod *iod); @@ -1093,13 +1092,11 @@ 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); return BLK_EH_RESET_TIMER; } @@ -1496,9 +1493,15 @@ 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)); @@ -2228,33 +2231,17 @@ 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) -- 2.39.5