Re: [PATCH 02/12] locking/rwsem: Exit early when held by an anonymous owner
From: Waiman Long
Date: Tue Jan 14 2020 - 13:33:44 EST
On 1/14/20 1:25 PM, Christoph Hellwig wrote:
> On Tue, Jan 14, 2020 at 01:17:45PM -0500, Waiman Long wrote:
>> The owner field is just a pointer to the task structure with the lower 3
>> bits served as flag bits. Setting owner to RWSEM_OWNER_UNKNOWN (-2) will
>> stop optimistic spinning. So under what condition did the crash happen?
> When running xfstests with all patches in this series except for this
> one, IIRC in generic/114.
OK, I think I know where the bug is. I will send a patch to fix that.
Thanks,
Longman