diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2024-09-11 17:34:37 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2024-09-11 10:44:10 -0600 |
| commit | 6746ee4c3a189f8b60694f01e7e29bc5ff7972e0 (patch) | |
| tree | 6ab9e275c7681d7a8c2d1c9849fc053376a33527 | |
| parent | 6d0f8dcb3a634bbee46fcb028c5984c463f47812 (diff) | |
io_uring/cmd: expose iowq to cmds
When an io_uring request needs blocking context we offload it to the
io_uring's thread pool called io-wq. We can get there off ->uring_cmd
by returning -EAGAIN, but there is no straightforward way of doing that
from an asynchronous callback. Add a helper that would transfer a
command to a blocking context.
Note, we do an extra hop via task_work before io_queue_iowq(), that's a
limitation of io_uring infra we have that can likely be lifted later
if that would ever become a problem.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f735f807d7c8ba50c9452c69dfe5d3e9e535037b.1726072086.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | include/linux/io_uring/cmd.h | 6 | ||||
| -rw-r--r-- | io_uring/io_uring.c | 11 | ||||
| -rw-r--r-- | io_uring/io_uring.h | 1 | ||||
| -rw-r--r-- | io_uring/uring_cmd.c | 7 |
4 files changed, 25 insertions, 0 deletions
diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h index 447fbfd32215..86ceb3383e49 100644 --- a/include/linux/io_uring/cmd.h +++ b/include/linux/io_uring/cmd.h @@ -48,6 +48,9 @@ void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd, void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd, unsigned int issue_flags); +/* Execute the request from a blocking context */ +void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd); + #else static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, struct iov_iter *iter, void *ioucmd) @@ -67,6 +70,9 @@ static inline void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd, unsigned int issue_flags) { } +static inline void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd) +{ +} #endif /* diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 1aca501efaf6..86cf31902841 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -533,6 +533,17 @@ static void io_queue_iowq(struct io_kiocb *req) io_queue_linked_timeout(link); } +static void io_req_queue_iowq_tw(struct io_kiocb *req, struct io_tw_state *ts) +{ + io_queue_iowq(req); +} + +void io_req_queue_iowq(struct io_kiocb *req) +{ + req->io_task_work.func = io_req_queue_iowq_tw; + io_req_task_work_add(req); +} + static __cold void io_queue_deferred(struct io_ring_ctx *ctx) { while (!list_empty(&ctx->defer_list)) { diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h index 65078e641390..9d70b2cf7b1e 100644 --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -94,6 +94,7 @@ int io_uring_alloc_task_context(struct task_struct *task, int io_ring_add_registered_file(struct io_uring_task *tctx, struct file *file, int start, int end); +void io_req_queue_iowq(struct io_kiocb *req); int io_poll_issue(struct io_kiocb *req, struct io_tw_state *ts); int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr); diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c index 8391c7c7c1ec..39c3c816ec78 100644 --- a/io_uring/uring_cmd.c +++ b/io_uring/uring_cmd.c @@ -277,6 +277,13 @@ int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, } EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); +void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd) +{ + struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); + + io_req_queue_iowq(req); +} + static inline int io_uring_cmd_getsockopt(struct socket *sock, struct io_uring_cmd *cmd, unsigned int issue_flags) |