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io_uring: force multishot CQEs into task context

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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>
This commit is contained in:
Pavel Begunkov 2022-12-07 03:53:31 +00:00 committed by Jens Axboe
parent e6aeb2721d
commit 17add5cea2
1 changed files with 21 additions and 0 deletions
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21
io_uring/net.c
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@ -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);