lkml.org 
[lkml]   [2019]   [Aug]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v5 1/6] mm/page_idle: Add per-pid idle page tracking using virtual index
On Wed, Aug 07, 2019 at 01:04:02PM -0700, Andrew Morton wrote:
> On Wed, 7 Aug 2019 13:15:54 -0400 "Joel Fernandes (Google)" <joel@joelfernandes.org> wrote:
>
> > In Android, we are using this for the heap profiler (heapprofd) which
> > profiles and pin points code paths which allocates and leaves memory
> > idle for long periods of time. This method solves the security issue
> > with userspace learning the PFN, and while at it is also shown to yield
> > better results than the pagemap lookup, the theory being that the window
> > where the address space can change is reduced by eliminating the
> > intermediate pagemap look up stage. In virtual address indexing, the
> > process's mmap_sem is held for the duration of the access.
>
> So is heapprofd a developer-only thing? Is heapprofd included in
> end-user android loads? If not then, again, wouldn't it be better to
> make the feature Kconfigurable so that Android developers can enable it
> during development then disable it for production kernels?

Almost all of this code is already configurable with
CONFIG_IDLE_PAGE_TRACKING. If you disable it, then all of this code gets
disabled.

Or are you referring to something else that needs to be made configurable?

thanks,

- Joel

\
 
 \ /
  Last update: 2019-08-07 22:46    [W:0.299 / U:0.408 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site