From 29dc5d06613f2438ec20a4ba5e0a5a740584d346 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 19 May 2023 14:50:24 +0800 Subject: [PATCH] ublk: kill queuing request by task_work_add task_work_add() is used from early ublk development stage for handling request in batch. However, since commit 7d4a93176e01 ("ublk_drv: don't forward io commands in reserve order"), we can get similar batch processing with io_uring_cmd_complete_in_task(), and similar performance data is observed between task_work_add() and io_uring_cmd_complete_in_task(). Meantime we can kill one fast code path, which is actually seldom used given it is common to build ublk driver as module. Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20230519065030.351216-2-ming.lei@redhat.com Signed-off-by: Jens Axboe --- drivers/block/ublk_drv.c | 40 ++-------------------------------------- 1 file changed, 2 insertions(+), 38 deletions(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index c7ed5d6..b00c5c2 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -62,7 +62,6 @@ struct ublk_rq_data { struct llist_node node; - struct callback_head work; }; struct ublk_uring_cmd_pdu { @@ -290,14 +289,6 @@ static int ublk_apply_params(struct ublk_device *ub) return 0; } -static inline bool ublk_can_use_task_work(const struct ublk_queue *ubq) -{ - if (IS_BUILTIN(CONFIG_BLK_DEV_UBLK) && - !(ubq->flags & UBLK_F_URING_CMD_COMP_IN_TASK)) - return true; - return false; -} - static inline bool ublk_need_get_data(const struct ublk_queue *ubq) { return ubq->flags & UBLK_F_NEED_GET_DATA; @@ -852,17 +843,6 @@ static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd, unsigned issue_flags) ublk_forward_io_cmds(ubq, issue_flags); } -static void ublk_rq_task_work_fn(struct callback_head *work) -{ - struct ublk_rq_data *data = container_of(work, - struct ublk_rq_data, work); - struct request *req = blk_mq_rq_from_pdu(data); - struct ublk_queue *ubq = req->mq_hctx->driver_data; - unsigned issue_flags = IO_URING_F_UNLOCKED; - - ublk_forward_io_cmds(ubq, issue_flags); -} - static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq) { struct ublk_rq_data *data = blk_mq_rq_to_pdu(rq); @@ -886,10 +866,6 @@ static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq) */ if (unlikely(io->flags & UBLK_IO_FLAG_ABORTED)) { ublk_abort_io_cmds(ubq); - } else if (ublk_can_use_task_work(ubq)) { - if (task_work_add(ubq->ubq_daemon, &data->work, - TWA_SIGNAL_NO_IPI)) - ublk_abort_io_cmds(ubq); } else { struct io_uring_cmd *cmd = io->cmd; struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); @@ -961,19 +937,9 @@ static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data, return 0; } -static int ublk_init_rq(struct blk_mq_tag_set *set, struct request *req, - unsigned int hctx_idx, unsigned int numa_node) -{ - struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); - - init_task_work(&data->work, ublk_rq_task_work_fn); - return 0; -} - static const struct blk_mq_ops ublk_mq_ops = { .queue_rq = ublk_queue_rq, .init_hctx = ublk_init_hctx, - .init_request = ublk_init_rq, .timeout = ublk_timeout, }; @@ -1813,10 +1779,8 @@ static int ublk_ctrl_add_dev(struct io_uring_cmd *cmd) */ ub->dev_info.flags &= UBLK_F_ALL; - if (!IS_BUILTIN(CONFIG_BLK_DEV_UBLK)) - ub->dev_info.flags |= UBLK_F_URING_CMD_COMP_IN_TASK; - - ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE; + ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE | + UBLK_F_URING_CMD_COMP_IN_TASK; /* We are not ready to support zero copy */ ub->dev_info.flags &= ~UBLK_F_SUPPORT_ZERO_COPY; -- 2.7.4