Re: [PATCH 1/8] cgroup: kill cgroup_subsys->__DEPRECATED_clear_css_refs

From: Tejun Heo
Date: Wed Oct 31 2012 - 16:10:56 EST


Hello,

On Wed, Oct 31, 2012 at 1:08 PM, Michal Hocko <mhocko@xxxxxxx> wrote:
> local_irq_disable doesn't guarantee atomicity, because other CPUs will

Maybe it should say atomicity on the local CPU.

> see the change in steps so this is a bit misleading. The real reason
> AFAICS is that we do not want to hang in css_tryget from IRQ context
> (does this really happen btw.?) which would interrupt cgroup_rmdir
> between we add CSS_DEACT_BIAS and the group is marked CGRP_REMOVED.
> Or am I still missing the point?

Yeah, that's the correct one. We don't want tryget happening between
DEACT_BIAS and REMOVED as it can hang forever there.

Thanks.

--
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/