From: Jens Axboe <axboe@kernel.dk> mainline inclusion from mainline-v6.9-rc3 commit 73eaa2b583493b680c6f426531d6736c39643bfb category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IC6ES1 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- 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: Rasmus Karlsson <rasmus.karlsson@pajlada.com> Tested-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com> Tested-by: Iskren Chernev <me@iskren.info> Link: https://github.com/axboe/liburing/issues/1113 Signed-off-by: Jens Axboe <axboe@kernel.dk> Conflicts: io_uring/io_uring.c [Commit b3a4dbc89d40 ("io_uring/kbuf: Use slab for struct io_buffer objects") add initialization of io_buf_cachep.] Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> --- io_uring/io_uring.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index fa0370fdb1d6..6677213e07b4 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1109,6 +1109,7 @@ static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags); static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer); static struct kmem_cache *req_cachep; +static struct workqueue_struct *iou_wq __ro_after_init; static const struct file_operations io_uring_fops; @@ -9494,7 +9495,7 @@ static 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) @@ -10999,6 +11000,8 @@ static int __init io_uring_init(void) req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT); + + iou_wq = alloc_workqueue("iou_exit", WQ_UNBOUND, 64); return 0; }; __initcall(io_uring_init); -- 2.31.1