diff options
| author | Jens Axboe <axboe@kernel.dk> | 2022-04-26 12:11:33 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-05-05 17:09:31 -0600 |
| commit | 0455d4ccec548b0fb51db39a4d3350a7a80a0222 (patch) | |
| tree | dd14449acab4a4236eca3acb438f5c5e01db7c08 /fs/io_uring.c | |
| parent | 73911426aaaadbae54fa72359b33a7b6a56947db (diff) | |
| download | lwn-0455d4ccec548b0fb51db39a4d3350a7a80a0222.tar.gz lwn-0455d4ccec548b0fb51db39a4d3350a7a80a0222.zip | |
io_uring: add POLL_FIRST support for send/sendmsg and recv/recvmsg
If IORING_RECVSEND_POLL_FIRST is set for recv/recvmsg or send/sendmsg,
then we arm poll first rather than attempt a receive or send upfront.
This can be useful if we expect there to be no data (or space) available
for the request, as we can then avoid wasting time on the initial
issue attempt.
Reviewed-by: Hao Xu <howeyxu@tencent.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index efe4e92ad8ad..6db9ab8d4d15 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -637,6 +637,7 @@ struct io_sr_msg { int bgid; size_t len; size_t done_io; + unsigned int flags; }; struct io_open { @@ -5272,11 +5273,14 @@ static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_sr_msg *sr = &req->sr_msg; - if (unlikely(sqe->addr2 || sqe->file_index)) + if (unlikely(sqe->file_index)) return -EINVAL; sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); + sr->flags = READ_ONCE(sqe->addr2); + if (sr->flags & ~IORING_RECVSEND_POLL_FIRST) + return -EINVAL; sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL; if (sr->msg_flags & MSG_DONTWAIT) req->flags |= REQ_F_NOWAIT; @@ -5311,6 +5315,10 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags) kmsg = &iomsg; } + if (!(req->flags & REQ_F_POLLED) && + (sr->flags & IORING_RECVSEND_POLL_FIRST)) + return io_setup_async_msg(req, kmsg); + flags = req->sr_msg.msg_flags; if (issue_flags & IO_URING_F_NONBLOCK) flags |= MSG_DONTWAIT; @@ -5353,6 +5361,10 @@ static int io_send(struct io_kiocb *req, unsigned int issue_flags) int min_ret = 0; int ret; + if (!(req->flags & REQ_F_POLLED) && + (sr->flags & IORING_RECVSEND_POLL_FIRST)) + return -EAGAIN; + sock = sock_from_file(req->file); if (unlikely(!sock)) return -ENOTSOCK; @@ -5505,11 +5517,14 @@ static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_sr_msg *sr = &req->sr_msg; - if (unlikely(sqe->addr2 || sqe->file_index)) + if (unlikely(sqe->file_index)) return -EINVAL; sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); + sr->flags = READ_ONCE(sqe->addr2); + if (sr->flags & ~IORING_RECVSEND_POLL_FIRST) + return -EINVAL; sr->bgid = READ_ONCE(sqe->buf_group); sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL; if (sr->msg_flags & MSG_DONTWAIT) @@ -5546,6 +5561,10 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) kmsg = &iomsg; } + if (!(req->flags & REQ_F_POLLED) && + (sr->flags & IORING_RECVSEND_POLL_FIRST)) + return io_setup_async_msg(req, kmsg); + if (req->flags & REQ_F_BUFFER_SELECT) { kbuf = io_recv_buffer_select(req, issue_flags); if (IS_ERR(kbuf)) @@ -5603,6 +5622,10 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags) int ret, min_ret = 0; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + if (!(req->flags & REQ_F_POLLED) && + (sr->flags & IORING_RECVSEND_POLL_FIRST)) + return -EAGAIN; + sock = sock_from_file(req->file); if (unlikely(!sock)) return -ENOTSOCK; |