From: Pavel Begunkov Date: Wed, 30 Jun 2021 20:54:04 +0000 (+0100) Subject: io_uring: simplify task_work func X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=5b0a6acc73fcac5f7d17badd09275bf7b9b46603;p=uclinux-h8%2Flinux.git io_uring: simplify task_work func Since we don't really use req->task_work anymore, get rid of it together with the nasty ->func aliasing between ->io_task_work and ->task_work, and hide ->fallback_node inside of io_task_work. Also, as task_work is gone now, replace the callback type from task_work_func_t to a function taking io_kiocb to avoid casting and simplify code. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe --- diff --git a/fs/io_uring.c b/fs/io_uring.c index ceb122a4ff78..5b840bb1e8ec 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -785,9 +785,14 @@ struct async_poll { struct io_poll_iocb *double_poll; }; +typedef void (*io_req_tw_func_t)(struct io_kiocb *req); + struct io_task_work { - struct io_wq_work_node node; - task_work_func_t func; + union { + struct io_wq_work_node node; + struct llist_node fallback_node; + }; + io_req_tw_func_t func; }; enum { @@ -850,18 +855,13 @@ struct io_kiocb { /* used with ctx->iopoll_list with reads/writes */ struct list_head inflight_entry; - union { - struct io_task_work io_task_work; - struct callback_head task_work; - }; + struct io_task_work io_task_work; /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */ struct hlist_node hash_node; struct async_poll *apoll; struct io_wq_work work; const struct cred *creds; - struct llist_node fallback_node; - /* store used ubuf, so we can prevent reloading */ struct io_mapped_ubuf *imu; }; @@ -1935,7 +1935,7 @@ static void tctx_task_work(struct callback_head *cb) ctx = req->ctx; percpu_ref_get(&ctx->refs); } - req->task_work.func(&req->task_work); + req->io_task_work.func(req); node = next; } if (wq_list_empty(&tctx->task_list)) { @@ -2006,16 +2006,16 @@ static int io_req_task_work_add(struct io_kiocb *req) } static void io_req_task_work_add_fallback(struct io_kiocb *req, - task_work_func_t cb) + io_req_tw_func_t cb) { - init_task_work(&req->task_work, cb); - if (llist_add(&req->fallback_node, &req->ctx->fallback_llist)) + req->io_task_work.func = cb; + if (llist_add(&req->io_task_work.fallback_node, + &req->ctx->fallback_llist)) schedule_delayed_work(&req->ctx->fallback_work, 1); } -static void io_req_task_cancel(struct callback_head *cb) +static void io_req_task_cancel(struct io_kiocb *req) { - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); struct io_ring_ctx *ctx = req->ctx; /* ctx is guaranteed to stay alive while we hold uring_lock */ @@ -2024,7 +2024,7 @@ static void io_req_task_cancel(struct callback_head *cb) mutex_unlock(&ctx->uring_lock); } -static void __io_req_task_submit(struct io_kiocb *req) +static void io_req_task_submit(struct io_kiocb *req) { struct io_ring_ctx *ctx = req->ctx; @@ -2037,17 +2037,10 @@ static void __io_req_task_submit(struct io_kiocb *req) mutex_unlock(&ctx->uring_lock); } -static void io_req_task_submit(struct callback_head *cb) -{ - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); - - __io_req_task_submit(req); -} - static void io_req_task_queue_fail(struct io_kiocb *req, int ret) { req->result = ret; - req->task_work.func = io_req_task_cancel; + req->io_task_work.func = io_req_task_cancel; if (unlikely(io_req_task_work_add(req))) io_req_task_work_add_fallback(req, io_req_task_cancel); @@ -2055,7 +2048,7 @@ static void io_req_task_queue_fail(struct io_kiocb *req, int ret) static void io_req_task_queue(struct io_kiocb *req) { - req->task_work.func = io_req_task_submit; + req->io_task_work.func = io_req_task_submit; if (unlikely(io_req_task_work_add(req))) io_req_task_queue_fail(req, -ECANCELED); @@ -2169,18 +2162,11 @@ static inline void io_put_req(struct io_kiocb *req) io_free_req(req); } -static void io_put_req_deferred_cb(struct callback_head *cb) -{ - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); - - io_free_req(req); -} - static void io_free_req_deferred(struct io_kiocb *req) { - req->task_work.func = io_put_req_deferred_cb; + req->io_task_work.func = io_free_req; if (unlikely(io_req_task_work_add(req))) - io_req_task_work_add_fallback(req, io_put_req_deferred_cb); + io_req_task_work_add_fallback(req, io_free_req); } static inline void io_put_req_deferred(struct io_kiocb *req, int refs) @@ -2466,8 +2452,8 @@ static void io_fallback_req_func(struct work_struct *work) struct llist_node *node = llist_del_all(&ctx->fallback_llist); struct io_kiocb *req, *tmp; - llist_for_each_entry_safe(req, tmp, node, fallback_node) - req->task_work.func(&req->task_work); + llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node) + req->io_task_work.func(req); } static void __io_complete_rw(struct io_kiocb *req, long res, long res2, @@ -4835,7 +4821,7 @@ struct io_poll_table { }; static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, - __poll_t mask, task_work_func_t func) + __poll_t mask, io_req_tw_func_t func) { int ret; @@ -4848,7 +4834,7 @@ static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, list_del_init(&poll->wait.entry); req->result = mask; - req->task_work.func = func; + req->io_task_work.func = func; /* * If this fails, then the task is exiting. When a task exits, the @@ -4945,9 +4931,8 @@ static bool io_poll_complete(struct io_kiocb *req, __poll_t mask) return !(flags & IORING_CQE_F_MORE); } -static void io_poll_task_func(struct callback_head *cb) +static void io_poll_task_func(struct io_kiocb *req) { - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); struct io_ring_ctx *ctx = req->ctx; struct io_kiocb *nxt; @@ -4969,7 +4954,7 @@ static void io_poll_task_func(struct callback_head *cb) if (done) { nxt = io_put_req_find_next(req); if (nxt) - __io_req_task_submit(nxt); + io_req_task_submit(nxt); } } } @@ -5078,9 +5063,8 @@ static void io_async_queue_proc(struct file *file, struct wait_queue_head *head, __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll); } -static void io_async_task_func(struct callback_head *cb) +static void io_async_task_func(struct io_kiocb *req) { - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); struct async_poll *apoll = req->apoll; struct io_ring_ctx *ctx = req->ctx; @@ -5096,7 +5080,7 @@ static void io_async_task_func(struct callback_head *cb) spin_unlock_irq(&ctx->completion_lock); if (!READ_ONCE(apoll->poll.canceled)) - __io_req_task_submit(req); + io_req_task_submit(req); else io_req_complete_failed(req, -ECANCELED); } @@ -8817,7 +8801,7 @@ static void io_ring_exit_work(struct work_struct *work) /* * Some may use context even when all refs and requests have been put, * and they are free to do so while still holding uring_lock or - * completion_lock, see __io_req_task_submit(). Apart from other work, + * completion_lock, see io_req_task_submit(). Apart from other work, * this lock/unlock section also waits them to finish. */ mutex_lock(&ctx->uring_lock);