Re: [PATCH 00/10] mm: Linux VM Infrastructure to support Memory Power Management

Hi,

On Fri, Jun 10, 2011 at 08:02:33PM -0700, Arjan van de Ven wrote:

On Fri, 10 Jun 2011 12:37:13 -0700
"Paul E. McKenney" [off-list ref] wrote:

quoted

On Fri, Jun 10, 2011 at 08:23:29PM +0100, Matthew Garrett wrote:

quoted

On Fri, Jun 10, 2011 at 11:47:38AM -0700, Paul E. McKenney wrote:

quoted

And if I understand you correctly, then the patches that Ankita
posted should help your self-refresh case, along with the
originally intended the power-down case and special-purpose use
of memory case.

Yeah, I'd hope so once we actually have capable hardware.

Cool!!!

So Ankita's patchset might be useful to you at some point, then.

Does it look like a reasonable implementation?

as someone who is working on hardware that is PASR capable right now,
I have to admit that our plan was to just hook into the buddy allocator,
and use PASR on the top level of buddy (eg PASR off blocks that are
free there, and PASR them back on once an allocation required the block
to be broken up)..... that looked the very most simple to me.

The maximum order in buddy allocator is by default 1k pages. Isn't this
too small a granularity to track blocks that might comprise a PASR unit? 

Maybe something much more elaborate is needed, but I didn't see why so
far.

-- 
Regards,
Ankita Garg (ankita@in.ibm.com)
Linux Technology Center
IBM India Systems & Technology Labs,
Bangalore, India