Re: [PATCH 1/2] rcu: cosmetic, delete wrong comment, use HARDIRQ_OFFSET

[Oleg Nesterov]

William Lee Irwin III wrote:
>
> On Sun, Nov 28, 2004 at 06:06:52PM +0300, Oleg Nesterov wrote:
> >
> > Afaics, this comment is misleading. rcu_check_quiescent_state()
> > is executed in softirq context, while rcu_check_callbacks() checks
> > in_softirq() before ++qsctr.
>
> rcu_qsctr_inc() does *NOT* check in_softirq(), and yes, scheduling
> does occur directly off the timer interrupt. For instance, for
> userspace tasks whose timeslices have expired.

But schedule()->rcu_qsctr_inc() can happen only after return from
do_softirq(), so where is the race?

Oleg.
-
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/