lkml.org 
[lkml]   [2006]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Patch1/4]: fake numa for x86_64 patch
On Wed, 22 Nov 2006, Rohit Seth wrote:

> This patch provides a IO hole size in a given address range.
>

Hi,

This patch reintroduces a function that doubles up what
absent_pages_in_range(start_pfn, end_pfn). I recognise you do this because
you are interested in hole sizes before add_active_range() is called.
However, what is not clear is why these patches are so specific to x86_64.

It looks possible to do the work of functions like split_nodes_equal() in
an architecture-independent manner using early_node_map rather than
dealing with the arch-specific nodes array. That would open the
possibility of providing fake nodes on more than one architecture in the
future.

What I think can be done is that you register memory as normal and then
split up the nodes into fake nodes. This would remove the need for having
e820_hole_size() reintroduced.

> Signed-off-by: David Rientjes <reintjes@google.com>
> Signed-off-by: Paul Menage <menage@google.com>
> Signed-off-by: Rohit Seth <rohitseth@google.com>
>
> --- linux-2.6.19-rc5-mm2.org/include/asm-x86_64/e820.h 2006-11-22 12:20:39.000000000 -0800
> +++ linux-2.6.19-rc5-mm2/include/asm-x86_64/e820.h 2006-11-22 12:17:25.000000000 -0800
> @@ -46,6 +46,7 @@ extern void e820_mark_nosave_regions(voi
> extern void e820_print_map(char *who);
> extern int e820_any_mapped(unsigned long start, unsigned long end, unsigned type);
> extern int e820_all_mapped(unsigned long start, unsigned long end, unsigned type);
> +extern unsigned long e820_hole_size(unsigned long start, unsigned long end);
>
> extern void e820_setup_gap(void);
> extern void e820_register_active_regions(int nid,
> --- linux-2.6.19-rc5-mm2.org/arch/x86_64/kernel/e820.c 2006-11-22 12:20:55.000000000 -0800
> +++ linux-2.6.19-rc5-mm2/arch/x86_64/kernel/e820.c 2006-11-21 18:48:15.000000000 -0800
> @@ -184,6 +184,38 @@ unsigned long __init e820_end_of_ram(voi
> }
>
> /*
> + * Find the hole size in the range.
> + */
> +unsigned long __init e820_hole_size(unsigned long start, unsigned long end)
> +{
> + unsigned long ram = 0;
> + int i;
> +
> + for (i = 0; i < e820.nr_map; i++) {
> + struct e820entry *ei = &e820.map[i];
> + unsigned long last, addr;
> +
> + if (ei->type != E820_RAM ||
> + ei->addr+ei->size <= start ||
> + ei->addr >= end)
> + continue;
> +
> + addr = round_up(ei->addr, PAGE_SIZE);
> + if (addr < start)
> + addr = start;
> +
> + last = round_down(ei->addr + ei->size, PAGE_SIZE);
> + if (last >= end)
> + last = end;
> +
> + if (last > addr)
> + ram += last - addr;
> + }
> + return ((end - start) - ram);
> +}
> +
> +
> +/*
> * Mark e820 reserved areas as busy for the resource manager.
> */
> void __init e820_reserve_resources(void)
>
>

--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab
-
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: 2006-11-27 14:21    [W:0.052 / U:13.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site