ublk_queue_cmd_list() dispatches the whole batch list by scheduling task
work via the tail request's io_uring_cmd, this way is fine even though
more than one io_ring_ctx are involved for this batch since it is just
one running context.
However, the task work handler ublk_cmd_list_tw_cb() takes `issue_flags`
of tail uring_cmd's io_ring_ctx for completing all commands. This way is
wrong if any uring_cmd is issued from different io_ring_ctx.
Fixes it by always building per-io-ring-ctx batch list.
For typical per-queue or per-io daemon implementation, this way shouldn't
make difference from performance viewpoint, because single io_ring_ctx is
often taken in each daemon.
Fixes: d796cea7b9f3 ("ublk: implement ->queue_rqs()")
Fixes: ab03a61c6614 ("ublk: have a per-io daemon instead of a per-queue daemon")
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
drivers/block/ublk_drv.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index c637ea010d34..e79b04e61047 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1336,9 +1336,8 @@ static void ublk_cmd_list_tw_cb(struct io_uring_cmd *cmd,
} while (rq);
}
-static void ublk_queue_cmd_list(struct ublk_io *io, struct rq_list *l)
+static void ublk_queue_cmd_list(struct io_uring_cmd *cmd, struct rq_list *l)
{
- struct io_uring_cmd *cmd = io->cmd;
struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
pdu->req_list = rq_list_peek(l);
@@ -1420,16 +1419,18 @@ static void ublk_queue_rqs(struct rq_list *rqlist)
{
struct rq_list requeue_list = { };
struct rq_list submit_list = { };
- struct ublk_io *io = NULL;
+ struct io_uring_cmd *cmd = NULL;
struct request *req;
while ((req = rq_list_pop(rqlist))) {
struct ublk_queue *this_q = req->mq_hctx->driver_data;
- struct ublk_io *this_io = &this_q->ios[req->tag];
+ struct io_uring_cmd *this_cmd = this_q->ios[req->tag].cmd;
- if (io && io->task != this_io->task && !rq_list_empty(&submit_list))
- ublk_queue_cmd_list(io, &submit_list);
- io = this_io;
+ if (cmd && io_uring_cmd_ctx_handle(cmd) !=
+ io_uring_cmd_ctx_handle(this_cmd) &&
+ !rq_list_empty(&submit_list))
+ ublk_queue_cmd_list(cmd, &submit_list);
+ cmd = this_cmd;
if (ublk_prep_req(this_q, req, true) == BLK_STS_OK)
rq_list_add_tail(&submit_list, req);
@@ -1438,7 +1439,7 @@ static void ublk_queue_rqs(struct rq_list *rqlist)
}
if (!rq_list_empty(&submit_list))
- ublk_queue_cmd_list(io, &submit_list);
+ ublk_queue_cmd_list(cmd, &submit_list);
*rqlist = requeue_list;
}
--
2.47.0
