Re: [PATCH v2 3/3] mm: remove superfluous __ClearPageWaiters()

2020-08-20 Thread Yu Zhao
On Thu, Aug 20, 2020 at 08:18:27AM +0200, Michal Hocko wrote: > On Tue 18-08-20 12:47:04, Yu Zhao wrote: > > Presumably __ClearPageWaiters() was added to follow the previously > > removed __ClearPageActive() pattern. > > I do not think so. Please have a look at 62906027091f ("mm: add > PageWaiters

Re: [PATCH v2 3/3] mm: remove superfluous __ClearPageWaiters()

2020-08-19 Thread Michal Hocko
On Tue 18-08-20 12:47:04, Yu Zhao wrote: > Presumably __ClearPageWaiters() was added to follow the previously > removed __ClearPageActive() pattern. I do not think so. Please have a look at 62906027091f ("mm: add PageWaiters indicating tasks are waiting for a page bit") and a discussion when the p

Re: [PATCH v2 3/3] mm: remove superfluous __ClearPageWaiters()

2020-08-19 Thread Yang Shi
On Wed, Aug 19, 2020 at 4:39 PM Yu Zhao wrote: > > On Wed, Aug 19, 2020 at 04:06:32PM -0700, Yang Shi wrote: > > On Tue, Aug 18, 2020 at 11:47 AM Yu Zhao wrote: > > > > > > Presumably __ClearPageWaiters() was added to follow the previously > > > removed __ClearPageActive() pattern. > > > > > > On

Re: [PATCH v2 3/3] mm: remove superfluous __ClearPageWaiters()

2020-08-19 Thread Yu Zhao
On Wed, Aug 19, 2020 at 04:06:32PM -0700, Yang Shi wrote: > On Tue, Aug 18, 2020 at 11:47 AM Yu Zhao wrote: > > > > Presumably __ClearPageWaiters() was added to follow the previously > > removed __ClearPageActive() pattern. > > > > Only flags that are in PAGE_FLAGS_CHECK_AT_FREE needs to be proper

Re: [PATCH v2 3/3] mm: remove superfluous __ClearPageWaiters()

2020-08-19 Thread Yang Shi
On Tue, Aug 18, 2020 at 11:47 AM Yu Zhao wrote: > > Presumably __ClearPageWaiters() was added to follow the previously > removed __ClearPageActive() pattern. > > Only flags that are in PAGE_FLAGS_CHECK_AT_FREE needs to be properly > cleared because otherwise we think there may be some kind of leak

[PATCH v2 3/3] mm: remove superfluous __ClearPageWaiters()

2020-08-18 Thread Yu Zhao
Presumably __ClearPageWaiters() was added to follow the previously removed __ClearPageActive() pattern. Only flags that are in PAGE_FLAGS_CHECK_AT_FREE needs to be properly cleared because otherwise we think there may be some kind of leak. PG_waiters is not one of those flags and leaving the clear