Re: [PATCH tip/core/rcu 06/22] rcu: Rename cond_resched_rcu_qs() to cond_resched_tasks_rcu_qs()
From: Paul E. McKenney
Date: Mon Apr 23 2018 - 08:31:26 EST
On Mon, Apr 23, 2018 at 10:53:47AM +0200, Peter Zijlstra wrote:
> On Sun, Apr 22, 2018 at 07:32:11PM -0700, Paul E. McKenney wrote:
> > Commit e31d28b6ab8f ("trace: Eliminate cond_resched_rcu_qs() in favor
> > of cond_resched()") substituted cond_resched() for the earlier call
> > to cond_resched_rcu_qs(). However, the new-age cond_resched() does
> > not do anything to help RCU-tasks grace periods because (1) RCU-tasks
> > is only enabled when CONFIG_PREEMPT=y and (2) cond_resched() is a
> > complete no-op when preemption is enabled. This situation results
> > in hangs when running the trace benchmarks.
>
> But a few patches earlier you tried to address that..
Yes. And all this patch does is change the name to better match
what this primitive actually does.
I could merge the two patches, if that would help.
Thanx, Paul