Re: [PATCH V3] mm/mprotect: Add a cond_resched() inside change_pmd_range()

From: Andrew Morton
Date: Thu Dec 14 2017 - 15:40:43 EST


On Thu, 14 Dec 2017 19:35:51 +0530 Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx> wrote:

> While testing on a large CPU system, detected the following RCU
> stall many times over the span of the workload. This problem
> is solved by adding a cond_resched() in the change_pmd_range()
> function.
>
> [ 850.962530] INFO: rcu_sched detected stalls on CPUs/tasks:

That's a bit rude. I think I'll add a cc:stable to this one.