Re: [PATCH v4 3/5] locking/rwsem: Change waiter->hanodff_set to a handoff_state enum

From: Waiman Long
Date: Mon Oct 24 2022 - 16:43:28 EST


On 10/24/22 14:25, john.p.donnelly@xxxxxxxxxx wrote:
On 10/24/22 12:44 PM, Waiman Long wrote:
Change the boolean waiter->handoff_set to an enum type so that we can
have more states in some later patches. Also use READ_ONCE() outside
wait_lock critical sections for read and WRITE_ONCE() inside wait_lock
critical sections for write for proper synchronization. There is no
functional change.

Hi,

Do we need


Fixes: d257cc8cb8d5 ("locking/rwsem: Make handoff bit handling more consistent")

Fixes: 91d2a812dfb9 ("locking/rwsem: Make handoff writer optimistically spin on owner")

Cc: stable@xxxxxxxxxxxxxxx


clauses added to patches 3,4,5 so they are all picked up in one series ?

Thank you,

John.

I am not planning to do that. The handoff code rewrite represent a moderate amount of changes. So I don't want them to be backported to stable in case there are some hidden bugs inside. That is why I have patch 2 is essentially reverted in patch 4.

Cheers,
Longman