Rather than use the system unbound event workqueue, use an io_uring specific one. This avoids dependencies with the tty, which also uses the system_unbound_wq, and issues flushes of said workqueue from inside its poll handling. Cc: stable@xxxxxxxxxxxxxxx Link: https://github.com/axboe/liburing/issues/1113 Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> --- diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 8baf8afb79c2..d1defb99b89e 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -147,6 +147,7 @@ static bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx, static void io_queue_sqe(struct io_kiocb *req); struct kmem_cache *req_cachep; +static struct workqueue_struct *iou_wq __ro_after_init; static int __read_mostly sysctl_io_uring_disabled; static int __read_mostly sysctl_io_uring_group = -1; @@ -3166,7 +3167,7 @@ static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) * noise and overhead, there's no discernable change in runtime * over using system_wq. */ - queue_work(system_unbound_wq, &ctx->exit_work); + queue_work(iou_wq, &ctx->exit_work); } static int io_uring_release(struct inode *inode, struct file *file) @@ -4190,6 +4191,8 @@ static int __init io_uring_init(void) io_buf_cachep = KMEM_CACHE(io_buffer, SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT); + iou_wq = alloc_workqueue("iou_exit", WQ_UNBOUND, 64); + #ifdef CONFIG_SYSCTL register_sysctl_init("kernel", kernel_io_uring_disabled_table); #endif -- Jens Axboe
