lkml.org 
[lkml]   [2005]   [Apr]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC][PATCH] nameing reserved pages [0/3]
From
Date
On Wed, 2005-04-20 at 14:34 +0200, Arjan van de Ven wrote:
> On Wed, 2005-04-20 at 21:02 +0900, KAMEZAWA Hiroyuki wrote:
> > Hi,
> >
> > There are several types of PG_reserved pages,
> > (a) Memory Hole
> > (b) Used by Kernel
> > (c) Set by drivers
> > (d) Isorated by MCA
> > (e) used by perfmon
> > etc....
> >
> > I think it's useful to distinguish many types of PG_reserved pages.
>
> I'm not so sure about this. at all.

Neither am I, that's why I hoped somebody would figure out something
better :)

> > For example, Memory Hotplug can ignore (a).
>
> Memory Hotplug can also use page_is_ram().

It uses this, to some degree, internally. But, things like the e820
table don't get updated as memory hotplugs occur.

This should a way to give more fine-grained information about what pages
are availabe as RAM at any point in time. kdump would need something
like this to figure out which pages inside of /dev/mem are actually
valid to dump. Here was another approach that used /proc files:

http://lkml.org/lkml/2005/3/24/11

> /dev/memstate really looks like a bad idea to me as well... I rather
> have less than more /dev/*mem*

Any other ideas?

-- Dave

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-04-20 20:57    [W:0.073 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site