Commit 73eaa2b5 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: use private workqueue for exit work 



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@vger.kernel.org
Reported-by: default avatarRasmus Karlsson <rasmus.karlsson@pajlada.com>
Tested-by: default avatarRasmus Karlsson <rasmus.karlsson@pajlada.com>
Tested-by: default avatarIskren Chernev <me@iskren.info>
Link: https://github.com/axboe/liburing/issues/1113


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent bee1d5be

io_uring/io_uring.c

+4 −1
Original line number Diff line number Diff line
@@ -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