Re: [PATCH block/for-3.4/core] cfq: fix cfqg ref handling when BLK_CGROUP && !CFQ_GROUP_IOSCHED

Vivek Goyal
2012-03-15T16:46:55Z

On Thu, Mar 15, 2012 at 09:35:46AM -0700, Tejun Heo wrote:

[..]
> ---
> Yeap, forgot to test that config combination. Fengguang, can you
> please test this patch? Jens, once Fengguang confirms the fix, can
> you please apply this on top of for-3.4/core along with the pending
> stats updates?

I was working on similar patch and you beat me to it. :-) One comment
below.

[..]
> @@ -3533,7 +3551,7 @@ static int cfq_init_queue(struct request
>
> spin_lock_irq(q->queue_lock);
> cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, cfqd->root_group);
> - blkg_put(cfqg_to_blkg(cfqd->root_group));
> + cfqg_put(cfqd->root_group);

This seems to be a spurious cfqg_put()? Which reference we are putting
down here?

Thanks
Vivek