static void io_poll_remove_all(struct io_ring_ctx *ctx)
{
	struct rb_node *node;
	struct io_kiocb *req;

	spin_lock_irq(&ctx->completion_lock);
	while ((node = rb_first(&ctx->cancel_tree)) != NULL) {
		req = rb_entry(node, struct io_kiocb, rb_node);
		io_poll_remove_one(req);
	}
	spin_unlock_irq(&ctx->completion_lock);
}
static void io_poll_remove_all(struct io_ring_ctx *ctx)
{
	struct rb_node *node;
	struct io_kiocb *req;

	spin_lock_irq(&ctx->completion_lock);
	while ((node = rb_first(&ctx->cancel_tree)) != NULL) {
		req = rb_entry(node, struct io_kiocb, rb_node);
		io_poll_remove_one(req);
	}
	spin_unlock_irq(&ctx->completion_lock);
}