diff options
| author | Jens Axboe | 2022-05-27 10:55:07 -0600 |
|---|---|---|
| committer | Jens Axboe | 2022-07-24 18:39:12 -0600 |
| commit | b9ba8a4463cd78d0aee520c4bf2569820ac29929 (patch) | |
| tree | 7ffcd2042e9e3bec8f314b0e3b997cca4613b591 /io_uring | |
| parent | d9b57aa3cfc792ccac6858376c017dbea6cb2872 (diff) | |
io_uring: add support for level triggered poll
By default, the POLL_ADD command does edge triggered poll - if we get
a non-zero mask on the initial poll attempt, we complete the request
successfully.
Support level triggered by always waiting for a notification, regardless
of whether or not the initial mask matches the file state.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/poll.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/io_uring/poll.c b/io_uring/poll.c index b80f7fa26123..558dc170468a 100644 --- a/io_uring/poll.c +++ b/io_uring/poll.c @@ -423,11 +423,13 @@ static int __io_arm_poll_handler(struct io_kiocb *req, atomic_set(&req->poll_refs, 1); mask = vfs_poll(req->file, &ipt->pt) & poll->events; - if (mask && (poll->events & EPOLLONESHOT)) { + if (mask && + ((poll->events & (EPOLLET|EPOLLONESHOT)) == (EPOLLET|EPOLLONESHOT))) { io_poll_remove_entries(req); /* no one else has access to the req, forget about the ref */ return mask; } + if (!mask && unlikely(ipt->error || !ipt->nr_entries)) { io_poll_remove_entries(req); if (!ipt->error) @@ -439,7 +441,7 @@ static int __io_arm_poll_handler(struct io_kiocb *req, io_poll_req_insert(req); spin_unlock(&ctx->completion_lock); - if (mask) { + if (mask && (poll->events & EPOLLET)) { /* can't multishot if failed, just queue the event we've got */ if (unlikely(ipt->error || !ipt->nr_entries)) { poll->events |= EPOLLONESHOT; @@ -475,7 +477,7 @@ int io_arm_poll_handler(struct io_kiocb *req, unsigned issue_flags) struct io_ring_ctx *ctx = req->ctx; struct async_poll *apoll; struct io_poll_table ipt; - __poll_t mask = POLLPRI | POLLERR; + __poll_t mask = POLLPRI | POLLERR | EPOLLET; int ret; if (!def->pollin && !def->pollout) @@ -638,7 +640,10 @@ static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe, #endif if (!(flags & IORING_POLL_ADD_MULTI)) events |= EPOLLONESHOT; - return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT)); + if (!(flags & IORING_POLL_ADD_LEVEL)) + events |= EPOLLET; + return demangle_poll(events) | + (events & (EPOLLEXCLUSIVE|EPOLLONESHOT|EPOLLET)); } int io_poll_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) @@ -679,7 +684,7 @@ int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sqe->buf_index || sqe->off || sqe->addr) return -EINVAL; flags = READ_ONCE(sqe->len); - if (flags & ~IORING_POLL_ADD_MULTI) + if (flags & ~(IORING_POLL_ADD_MULTI|IORING_POLL_ADD_LEVEL)) return -EINVAL; if ((flags & IORING_POLL_ADD_MULTI) && (req->flags & REQ_F_CQE_SKIP)) return -EINVAL; |