lkml.org 
[lkml]   [2015]   [Jul]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/2] mm/shrinker: make unregister_shrinker() less fragile
On (07/12/15 23:33), Christoph Hellwig wrote:
> On Sun, Jul 12, 2015 at 11:47:32AM +0900, Sergey Senozhatsky wrote:
> > Yes, but the main difference here is that it seems that shrinker users
> > don't tend to treat shrinker registration failures as fatal errors and
> > just continue with shrinker functionality disabled. And it makes sense.
> >
> > (copy paste from https://lkml.org/lkml/2015/7/9/751)
> >
>
> I hearily disagree. It's not any less critical than other failures.

Why? In some sense, shrinker callbacks are just a way to be nice.
No one writes a driver just to be able to handle shrinker calls. An
ability to react to those calls is just additional option; it does
not directly affect or limit driver's functionality (at least, it
really should not).

> The right way forward is to handle register failure properly.

In other words, to
(a) keep a flag to signify that register was not successful
or
(b) look at ->shrinker.list.next or ->nr_deferred
or
(c) treat register failures as critical errors. (I sort of
disagree with you here).

-ss


\
 
 \ /
  Last update: 2015-07-13 09:21    [W:0.068 / U:0.308 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site