From 4c6e277c4cc4a6b3b2b9c66a7b014787ae757cc1 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 1 Jul 2020 11:29:10 -0600 Subject: [PATCH] io_uring: abstract out task work running Provide a helper to run task_work instead of checking and running manually in a bunch of different spots. While doing so, also move the task run state setting where we run the task work. Then we can move it out of the callback helpers. This also helps ensure we only do this once per task_work list run, not per task_work item. Suggested-by: Oleg Nesterov Signed-off-by: Jens Axboe --- fs/io_uring.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 7426e4f23f9b..65a6978e1795 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1714,7 +1714,6 @@ static void __io_req_task_submit(struct io_kiocb *req) { struct io_ring_ctx *ctx = req->ctx; - __set_current_state(TASK_RUNNING); if (!__io_sq_thread_acquire_mm(ctx)) { mutex_lock(&ctx->uring_lock); __io_queue_sqe(req, NULL, NULL); @@ -1899,6 +1898,17 @@ static int io_put_kbuf(struct io_kiocb *req) return cflags; } +static inline bool io_run_task_work(void) +{ + if (current->task_works) { + __set_current_state(TASK_RUNNING); + task_work_run(); + return true; + } + + return false; +} + static void io_iopoll_queue(struct list_head *again) { struct io_kiocb *req; @@ -2079,8 +2089,7 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, */ if (!(++iters & 7)) { mutex_unlock(&ctx->uring_lock); - if (current->task_works) - task_work_run(); + io_run_task_work(); mutex_lock(&ctx->uring_lock); } @@ -2176,8 +2185,6 @@ static void io_rw_resubmit(struct callback_head *cb) struct io_ring_ctx *ctx = req->ctx; int err; - __set_current_state(TASK_RUNNING); - err = io_sq_thread_acquire_mm(ctx, req); if (io_resubmit_prep(req, err)) { @@ -6361,8 +6368,7 @@ static int io_sq_thread(void *data) if (!list_empty(&ctx->poll_list) || need_resched() || (!time_after(jiffies, timeout) && ret != -EBUSY && !percpu_ref_is_dying(&ctx->refs))) { - if (current->task_works) - task_work_run(); + io_run_task_work(); cond_resched(); continue; } @@ -6394,8 +6400,7 @@ static int io_sq_thread(void *data) finish_wait(&ctx->sqo_wait, &wait); break; } - if (current->task_works) { - task_work_run(); + if (io_run_task_work()) { finish_wait(&ctx->sqo_wait, &wait); continue; } @@ -6420,8 +6425,7 @@ static int io_sq_thread(void *data) timeout = jiffies + ctx->sq_thread_idle; } - if (current->task_works) - task_work_run(); + io_run_task_work(); io_sq_thread_drop_mm(ctx); revert_creds(old_cred); @@ -6486,9 +6490,8 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, do { if (io_cqring_events(ctx, false) >= min_events) return 0; - if (!current->task_works) + if (!io_run_task_work()) break; - task_work_run(); } while (1); if (sig) { @@ -6510,8 +6513,8 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, prepare_to_wait_exclusive(&ctx->wait, &iowq.wq, TASK_INTERRUPTIBLE); /* make sure we run task_work before checking for signals */ - if (current->task_works) - task_work_run(); + if (io_run_task_work()) + continue; if (signal_pending(current)) { if (current->jobctl & JOBCTL_TASK_WORK) { spin_lock_irq(¤t->sighand->siglock); @@ -7953,8 +7956,7 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, int submitted = 0; struct fd f; - if (current->task_works) - task_work_run(); + io_run_task_work(); if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP)) return -EINVAL; -- 2.11.0