Re: [PATCH] sched: don't take a mutex from interrupt context

From: Peter Zijlstra
Date: Tue Jan 22 2008 - 11:48:14 EST



On Tue, 2008-01-22 at 22:21 +0530, Srivatsa Vaddagiri wrote:
> On Tue, Jan 22, 2008 at 05:25:38PM +0100, Peter Zijlstra wrote:
> > @@ -1428,9 +1428,9 @@ static void print_cfs_stats(struct seq_f
> > #ifdef CONFIG_FAIR_GROUP_SCHED
> > print_cfs_rq(m, cpu, &cpu_rq(cpu)->cfs);
> > #endif
> > - lock_task_group_list();
> > + rcu_read_lock();
> > for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
> > print_cfs_rq(m, cpu, cfs_rq);
>
> Isn't there a possibility that print_cfs_rq() can block?

It should not, that would be another bug, but from a quick glance at the
code it doesn't do that.

>
> > - unlock_task_group_list();
> > + rcu_read_unlock();
> > }
> > #endif
> >
>

--
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/