Re: [PATCH 5/5] hugetlbfs: Limit wait time when trying to share huge PMD

From: Waiman Long
Date: Fri Sep 13 2019 - 14:23:48 EST

On 9/12/19 5:43 PM, Mike Kravetz wrote:
> On 9/12/19 2:06 AM, Waiman Long wrote:
>> If we can take the rwsem in read mode, that should solve the problem
>> AFAICS. As I don't have a full understanding of the history of that
>> code, I didn't try to do that in my patch.
> Do you still have access to an environment that creates the long stalls?
> If so, can you try the simple change of taking the semaphore in read mode
> in huge_pmd_share.
That is what I am planning to do. I don't have an environment to
reproduce the problem myself. I have to create a test kernel and ask the
customer to try it out.