diff options
author | Jens Axboe <axboe@kernel.dk> | 2019-12-09 17:52:20 -0700 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2019-12-10 16:33:23 -0700 |
commit | 392edb45b24337eaa0bc1ecd4e3cf897e662ec61 (patch) | |
tree | ab9d8463d266a7651792830d467879e62828c99e /fs/io_uring.c | |
parent | d96885658d9971fc2c752b8699f17a42ef745db6 (diff) |
io_uring: don't dynamically allocate poll data
This essentially reverts commit e944475e6984. For high poll ops
workloads, like TAO, the dynamic allocation of the wait_queue
entry for IORING_OP_POLL_ADD adds considerable extra overhead.
Go back to embedding the wait_queue_entry, but keep the usage of
wait->private for the pointer stashing.
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, 11 insertions, 16 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index b84def504201..89a2c8b4f8fb 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -293,7 +293,7 @@ struct io_poll_iocb { __poll_t events; bool done; bool canceled; - struct wait_queue_entry *wait; + struct wait_queue_entry wait; }; struct io_timeout_data { @@ -2286,8 +2286,8 @@ static void io_poll_remove_one(struct io_kiocb *req) spin_lock(&poll->head->lock); WRITE_ONCE(poll->canceled, true); - if (!list_empty(&poll->wait->entry)) { - list_del_init(&poll->wait->entry); + if (!list_empty(&poll->wait.entry)) { + list_del_init(&poll->wait.entry); io_queue_async_work(req); } spin_unlock(&poll->head->lock); @@ -2358,7 +2358,6 @@ static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error) struct io_ring_ctx *ctx = req->ctx; req->poll.done = true; - kfree(req->poll.wait); if (error) io_cqring_fill_event(req, error); else @@ -2396,7 +2395,7 @@ static void io_poll_complete_work(struct io_wq_work **workptr) */ spin_lock_irq(&ctx->completion_lock); if (!mask && ret != -ECANCELED) { - add_wait_queue(poll->head, poll->wait); + add_wait_queue(poll->head, &poll->wait); spin_unlock_irq(&ctx->completion_lock); return; } @@ -2426,7 +2425,7 @@ static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, if (mask && !(mask & poll->events)) return 0; - list_del_init(&poll->wait->entry); + list_del_init(&poll->wait.entry); /* * Run completion inline if we can. We're using trylock here because @@ -2467,7 +2466,7 @@ static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head, pt->error = 0; pt->req->poll.head = head; - add_wait_queue(head, pt->req->poll.wait); + add_wait_queue(head, &pt->req->poll.wait); } static void io_poll_req_insert(struct io_kiocb *req) @@ -2496,10 +2495,6 @@ static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe, if (!poll->file) return -EBADF; - poll->wait = kmalloc(sizeof(*poll->wait), GFP_KERNEL); - if (!poll->wait) - return -ENOMEM; - req->io = NULL; INIT_IO_WORK(&req->work, io_poll_complete_work); events = READ_ONCE(sqe->poll_events); @@ -2516,9 +2511,9 @@ static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe, ipt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ /* initialized the list so that we can do list_empty checks */ - INIT_LIST_HEAD(&poll->wait->entry); - init_waitqueue_func_entry(poll->wait, io_poll_wake); - poll->wait->private = poll; + INIT_LIST_HEAD(&poll->wait.entry); + init_waitqueue_func_entry(&poll->wait, io_poll_wake); + poll->wait.private = poll; INIT_LIST_HEAD(&req->list); @@ -2527,14 +2522,14 @@ static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe, spin_lock_irq(&ctx->completion_lock); if (likely(poll->head)) { spin_lock(&poll->head->lock); - if (unlikely(list_empty(&poll->wait->entry))) { + if (unlikely(list_empty(&poll->wait.entry))) { if (ipt.error) cancel = true; ipt.error = 0; mask = 0; } if (mask || ipt.error) - list_del_init(&poll->wait->entry); + list_del_init(&poll->wait.entry); else if (cancel) WRITE_ONCE(poll->canceled, true); else if (!poll->done) /* actually waiting for an event */ |