diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2022-12-07 03:53:31 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-12-07 06:47:13 -0700 |
| commit | 17add5cea2bbafea0d481f1a3ea9dea019a98ee9 (patch) | |
| tree | 55652b69cf57e7f16a461773ae78682bacf47e48 /io_uring | |
| parent | e6aeb2721d3bad8379c43644d0380908e93b0187 (diff) | |
| download | lwn-17add5cea2bbafea0d481f1a3ea9dea019a98ee9.tar.gz lwn-17add5cea2bbafea0d481f1a3ea9dea019a98ee9.zip | |
io_uring: force multishot CQEs into task context
Multishot are posting CQEs outside of the normal request completion
path, which is usually done from within a task work handler. However, it
might be not the case when it's yet to be polled but has been punted to
io-wq. Make it abide ->task_complete and push it to the polling path
when executed by io-wq.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d7714aaff583096769a0f26e8e747759e556feb1.1670384893.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/net.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/io_uring/net.c b/io_uring/net.c index 90342dcb6b1d..f276f6dd5b09 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -67,6 +67,19 @@ struct io_sr_msg { struct io_kiocb *notif; }; +static inline bool io_check_multishot(struct io_kiocb *req, + unsigned int issue_flags) +{ + /* + * When ->locked_cq is set we only allow to post CQEs from the original + * task context. Usual request completions will be handled in other + * generic paths but multipoll may decide to post extra cqes. + */ + return !(issue_flags & IO_URING_F_IOWQ) || + !(issue_flags & IO_URING_F_MULTISHOT) || + !req->ctx->task_complete; +} + int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown); @@ -730,6 +743,9 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) (sr->flags & IORING_RECVSEND_POLL_FIRST)) return io_setup_async_msg(req, kmsg, issue_flags); + if (!io_check_multishot(req, issue_flags)) + return io_setup_async_msg(req, kmsg, issue_flags); + retry_multishot: if (io_do_buffer_select(req)) { void __user *buf; @@ -829,6 +845,9 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) (sr->flags & IORING_RECVSEND_POLL_FIRST)) return -EAGAIN; + if (!io_check_multishot(req, issue_flags)) + return -EAGAIN; + sock = sock_from_file(req->file); if (unlikely(!sock)) return -ENOTSOCK; @@ -1280,6 +1299,8 @@ int io_accept(struct io_kiocb *req, unsigned int issue_flags) struct file *file; int ret, fd; + if (!io_check_multishot(req, issue_flags)) + return -EAGAIN; retry: if (!fixed) { fd = __get_unused_fd_flags(accept->flags, accept->nofile); |