On Wed, 2018-08-08 at 08:41 -0600, Jens Axboe wrote:

On 7/30/18 3:10 PM, Bart Van Assche wrote:

quoted

+#ifdef CONFIG_BLK_CGROUP
+	{
+		struct blkcg_gq *blkg;
+
+		rcu_read_lock();
+		blkg = blkg_lookup(&blkcg_root, q);
+		rcu_read_unlock();
+
+		WARN(blkg,
+		     "request queue %p is being released but it has=

 not yet been removed from the blkcg controller\n",

quoted

+		     q);
+	}
+#endif

=20
This last hunk should go in the cgroup code.

Hello Jens,

How about leaving out the #ifdef CONFIG_BLK_CGROUP / #endif=
? Would that be
sufficient? I just noticed that blkg_lookup() returns NULL anyway if cg=
roup support
is disabled in the kernel config.

Thanks,

Bart.