Hi,
在 2023/01/06 2:32, Tejun Heo 写道:
On Thu, Jan 05, 2023 at 09:14:07AM +0800, Yu Kuai wrote:
1) is related to blkg, while 2) is not, hence refcnting from blkg can't
fix the problem. refcnting from blkcg_policy_data should be ok, but I
see that bfq already has the similar refcnting, while other policy
doesn't require such refcnting.
Hmm... taking a step back, wouldn't this be solved by moving the first part
of ioc_pd_free() to pd_offline_fn()? The ordering is strictly defined there,
right?
Moving first part to pd_offline_fn() has some requirements, like what I
did in the other thread:
iocg can be activated again after pd_offline_fn(), which is possible
because bio can be dispatched when cgroup is removed. I tried to avoid
that by:
1) dispatch all throttled bio io ioc_pd_offline()
2) don't throttle bio after ioc_pd_offline()
However, you already disagreed with that. 😔
Thanks,
Kuai
Thanks.
--
tejun
.
