lkml.org 
[lkml]   [2021]   [Nov]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] mm: split thp synchronously on MADV_DONTNEED
On Sat, Nov 20, 2021 at 8:35 PM Matthew Wilcox <willy@infradead.org> wrote:
>
> On Sat, Nov 20, 2021 at 12:12:30PM -0800, Shakeel Butt wrote:
> > This patch let such applications not worry about the low level handling
> > of THPs in the kernel and splits the THPs synchronously on
> > MADV_DONTNEED.
>
> I don't mind the synchronous split, but I have concerns about the
> implementation. I don't think it's worth another pointer in task_struct.

Are you concerned about the size of task_struct? At least on my config
this additional pointer was just filling the holes and not increasing
the size. I can check a couple other configs as well.

> It's also the case that splitting is likely to succeed, so I think a
> better implementation would try to split and then put the page on the
> global deferred list if splitting fails.

Actually this is what this patch is doing. See the second loop in
split_local_deferred_list().

\
 
 \ /
  Last update: 2021-11-21 06:26    [W:0.123 / U:9.172 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site