From 90ea5ca45c1fa09bec83ea106b9947170a00edb8 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 26 May 2018 13:45:55 +0200 Subject: [PATCH] nvme-pci: simplify __nvme_submit_cmd With recent CQ handling improvements we can now move the locking into __nvme_submit_cmd. Also remove the local tail variable to make the code more obvious, remove the __ prefix in the name, and fix the comments describing the function. Signed-off-by: Christoph Hellwig Reviewed-by: Jens Axboe Reviewed-by: Max Gurtovoy --- drivers/nvme/host/pci.c | 37 ++++++++++++++----------------------- 1 file changed, 14 insertions(+), 23 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 9cd62a13ff1f..4d0bb0e45401 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -421,28 +421,25 @@ static int nvme_pci_map_queues(struct blk_mq_tag_set *set) } /** - * __nvme_submit_cmd() - Copy a command into a queue and ring the doorbell + * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell * @nvmeq: The queue to use * @cmd: The command to send - * - * Safe to use from interrupt context */ -static void __nvme_submit_cmd(struct nvme_queue *nvmeq, - struct nvme_command *cmd) +static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd) { - u16 tail = nvmeq->sq_tail; - + spin_lock(&nvmeq->sq_lock); if (nvmeq->sq_cmds_io) - memcpy_toio(&nvmeq->sq_cmds_io[tail], cmd, sizeof(*cmd)); + memcpy_toio(&nvmeq->sq_cmds_io[nvmeq->sq_tail], cmd, + sizeof(*cmd)); else - memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd)); + memcpy(&nvmeq->sq_cmds[nvmeq->sq_tail], cmd, sizeof(*cmd)); - if (++tail == nvmeq->q_depth) - tail = 0; - if (nvme_dbbuf_update_and_check_event(tail, nvmeq->dbbuf_sq_db, - nvmeq->dbbuf_sq_ei)) - writel(tail, nvmeq->q_db); - nvmeq->sq_tail = tail; + if (++nvmeq->sq_tail == nvmeq->q_depth) + nvmeq->sq_tail = 0; + if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail, + nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei)) + writel(nvmeq->sq_tail, nvmeq->q_db); + spin_unlock(&nvmeq->sq_lock); } static void **nvme_pci_iod_list(struct request *req) @@ -895,10 +892,7 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, } blk_mq_start_request(req); - - spin_lock(&nvmeq->sq_lock); - __nvme_submit_cmd(nvmeq, &cmnd); - spin_unlock(&nvmeq->sq_lock); + nvme_submit_cmd(nvmeq, &cmnd); return BLK_STS_OK; out_cleanup_iod: nvme_free_iod(dev, req); @@ -1058,10 +1052,7 @@ static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl) memset(&c, 0, sizeof(c)); c.common.opcode = nvme_admin_async_event; c.common.command_id = NVME_AQ_BLK_MQ_DEPTH; - - spin_lock(&nvmeq->sq_lock); - __nvme_submit_cmd(nvmeq, &c); - spin_unlock(&nvmeq->sq_lock); + nvme_submit_cmd(nvmeq, &c); } static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id) -- 2.45.2