From: Pavel Begunkov <asml.silence@gmail.com> mainline inclusion from mainline-5.12-rc1 commit eab30c4d20dc761d463445e5130421863ff81505 category: bugfix bugzilla: 182869 https://gitee.com/openeuler/kernel/issues/I4DDEL Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... --------------------------- When io_req_task_work_add() fails, the request will be cancelled by enqueueing via task_works of io-wq. Extract a function for that. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Conflicts: fs/io_uring.c [ 355fb9e2b78e78("io_uring: remove 'twa_signal_ok' deadlock work-around") is not applied. ] Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- fs/io_uring.c | 46 +++++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 29 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 0736487165da..353604296e7d 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2056,6 +2056,16 @@ static int io_req_task_work_add(struct io_kiocb *req, bool twa_signal_ok) return ret; } +static void io_req_task_work_add_fallback(struct io_kiocb *req, + void (*cb)(struct callback_head *)) +{ + struct task_struct *tsk = io_wq_get_task(req->ctx->io_wq); + + init_task_work(&req->task_work, cb); + task_work_add(tsk, &req->task_work, TWA_NONE); + wake_up_process(tsk); +} + static void __io_req_task_cancel(struct io_kiocb *req, int error) { struct io_ring_ctx *ctx = req->ctx; @@ -2111,14 +2121,8 @@ static void io_req_task_queue(struct io_kiocb *req) percpu_ref_get(&req->ctx->refs); ret = io_req_task_work_add(req, true); - if (unlikely(ret)) { - struct task_struct *tsk; - - init_task_work(&req->task_work, io_req_task_cancel); - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); - } + if (unlikely(ret)) + io_req_task_work_add_fallback(req, io_req_task_cancel); } static void io_queue_next(struct io_kiocb *req) @@ -2237,13 +2241,8 @@ static void io_free_req_deferred(struct io_kiocb *req) init_task_work(&req->task_work, io_put_req_deferred_cb); ret = io_req_task_work_add(req, true); - if (unlikely(ret)) { - struct task_struct *tsk; - - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); - } + if (unlikely(ret)) + io_req_task_work_add_fallback(req, io_put_req_deferred_cb); } static inline void io_put_req_deferred(struct io_kiocb *req, int refs) @@ -3343,15 +3342,8 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode, /* submit ref gets dropped, acquire a new one */ refcount_inc(&req->refs); ret = io_req_task_work_add(req, true); - if (unlikely(ret)) { - struct task_struct *tsk; - - /* queue just for cancelation */ - init_task_work(&req->task_work, io_req_task_cancel); - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); - } + if (unlikely(ret)) + io_req_task_work_add_fallback(req, io_req_task_cancel); return 1; } @@ -4961,12 +4953,8 @@ static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, */ ret = io_req_task_work_add(req, twa_signal_ok); if (unlikely(ret)) { - struct task_struct *tsk; - WRITE_ONCE(poll->canceled, true); - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); + io_req_task_work_add_fallback(req, func); } return 1; } -- 2.20.1