lkml.org 
[lkml]   [2016]   [Aug]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] radix-tree: account nodes to memcg only if explicitly requested
On Tue 02-08-16 15:42:20, Vladimir Davydov wrote:
> On Tue, Aug 02, 2016 at 01:51:12PM +0200, Michal Hocko wrote:
> > On Mon 01-08-16 16:13:08, Vladimir Davydov wrote:
> > > Radix trees may be used not only for storing page cache pages, so
> > > unconditionally accounting radix tree nodes to the current memory cgroup
> > > is bad: if a radix tree node is used for storing data shared among
> > > different cgroups we risk pinning dead memory cgroups forever. So let's
> > > only account radix tree nodes if it was explicitly requested by passing
> > > __GFP_ACCOUNT to INIT_RADIX_TREE. Currently, we only want to account
> > > page cache entries, so mark mapping->page_tree so.
> > >
> > > Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
> >
> > OK, the patch makes sense to me. Such a false sharing would be really
> > tedious to debug
> >
> > Do we want to mark it for stable 4.6 to prevent from some pathological
> > issues. The patch is simple enough.
>
> Makes sense, expecially taking into account that kmemcg is enabled by
> default now.
>
> I'll resend the patch for stable then.

Maybe Andrew just want's to mark it for stable with
Fixes: 58e698af4c63 ("radix-tree: account radix_tree_node to memory cgroup")
Cc: stable # 4.6

> > Acked-by: Michal Hocko <mhocko@suse.com>
>
> Thanks!
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

--
Michal Hocko
SUSE Labs

\
 
 \ /
  Last update: 2016-08-02 15:41    [W:0.086 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site