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.
Cc: Pavel Begunkov <asml.silence@xxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
drivers/block/ublk_drv.c | 39 ++-------------------------------------
1 file changed, 2 insertions(+), 37 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index cddfb33a5c3b..d6434c3354df 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 {
@@ -289,14 +288,6 @@ 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;
@@ -848,16 +839,6 @@ static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd)
ublk_forward_io_cmds(ubq);
}
-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;
-
- ublk_forward_io_cmds(ubq);
-}
-
static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
{
struct ublk_rq_data *data = blk_mq_rq_to_pdu(rq);
@@ -881,10 +862,6 @@ 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);
@@ -940,19 +917,9 @@ 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,
};
static int ublk_ch_open(struct inode *inode, struct file *filp)
@@ -1760,10 +1727,8 @@ 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;
--
2.39.2
