Re: [RFC PATCH 1/1] epoll: use rwlock in order to reduce ep_poll_callback() contention

From: Davidlohr Bueso
Date: Wed Dec 05 2018 - 22:08:37 EST


On 12/3/18 6:02 AM, Roman Penyaev wrote:

if (!ep_is_linked(epi)) {
- list_add_tail(&epi->rdllink, &ep->rdllist);
+ /* Reverse ->ovflist, events should be in FIFO */
+ list_add(&epi->rdllink, &ep->rdllist);
ep_pm_stay_awake(epi);
}

This should probably a separate patch as it fixes the ordering,
regardless of the rwlock+xchg optimization.

Thanks,
Davidlohr