From 9b46571142e47503ed4f3ae3be5ed3968d8cb9cc Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Mon, 15 Mar 2021 14:23:07 +0000 Subject: [PATCH] io_uring: add generic callback_head helpers We already have helpers to run/add callback_head but taking ctx and working with ctx->exit_task_work. Extract generic versions of them implemented in terms of struct callback_head, it will be used later. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe --- fs/io_uring.c | 62 ++++++++++++++++++++++++++++++++++------------------------- 1 file changed, 36 insertions(+), 26 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 70ceb8ed5950..5c2de43b99f5 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1929,17 +1929,44 @@ static int io_req_task_work_add(struct io_kiocb *req) return ret; } -static void io_req_task_work_add_fallback(struct io_kiocb *req, - task_work_func_t cb) +static bool io_run_task_work_head(struct callback_head **work_head) +{ + struct callback_head *work, *next; + bool executed = false; + + do { + work = xchg(work_head, NULL); + if (!work) + break; + + do { + next = work->next; + work->func(work); + work = next; + cond_resched(); + } while (work); + executed = true; + } while (1); + + return executed; +} + +static void io_task_work_add_head(struct callback_head **work_head, + struct callback_head *task_work) { - struct io_ring_ctx *ctx = req->ctx; struct callback_head *head; - init_task_work(&req->task_work, cb); do { - head = READ_ONCE(ctx->exit_task_work); - req->task_work.next = head; - } while (cmpxchg(&ctx->exit_task_work, head, &req->task_work) != head); + head = READ_ONCE(*work_head); + task_work->next = head; + } while (cmpxchg(work_head, head, task_work) != head); +} + +static void io_req_task_work_add_fallback(struct io_kiocb *req, + task_work_func_t cb) +{ + init_task_work(&req->task_work, cb); + io_task_work_add_head(&req->ctx->exit_task_work, &req->task_work); } static void __io_req_task_cancel(struct io_kiocb *req, int error) @@ -8471,26 +8498,9 @@ static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) return -EINVAL; } -static bool io_run_ctx_fallback(struct io_ring_ctx *ctx) +static inline bool io_run_ctx_fallback(struct io_ring_ctx *ctx) { - struct callback_head *work, *next; - bool executed = false; - - do { - work = xchg(&ctx->exit_task_work, NULL); - if (!work) - break; - - do { - next = work->next; - work->func(work); - work = next; - cond_resched(); - } while (work); - executed = true; - } while (1); - - return executed; + return io_run_task_work_head(&ctx->exit_task_work); } struct io_tctx_exit { -- 2.11.0