kernel-ark/include/asm-x86/sparsemem.h
Jeremy Fitzhardinge fb8e837539 x86: sparsemem: reduce i386 PAE section size
A 1G section size makes memory hotplug too coarse in a virtual
environment.  Retuce it by a factor of 2 to 512M.  I would have liked
to make it smaller, but it runs out of reserved flags in the page flags.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:33 +02:00

35 lines
868 B
C

#ifndef _ASM_X86_SPARSEMEM_H
#define _ASM_X86_SPARSEMEM_H
#ifdef CONFIG_SPARSEMEM
/*
* generic non-linear memory support:
*
* 1) we will not split memory into more chunks than will fit into the flags
* field of the struct page
*
* SECTION_SIZE_BITS 2^n: size of each section
* MAX_PHYSADDR_BITS 2^n: max size of physical address space
* MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space
*
*/
#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_PAE
# define SECTION_SIZE_BITS 29
# define MAX_PHYSADDR_BITS 36
# define MAX_PHYSMEM_BITS 36
# else
# define SECTION_SIZE_BITS 26
# define MAX_PHYSADDR_BITS 32
# define MAX_PHYSMEM_BITS 32
# endif
#else /* CONFIG_X86_32 */
# define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */
# define MAX_PHYSADDR_BITS 44
# define MAX_PHYSMEM_BITS 44
#endif
#endif /* CONFIG_SPARSEMEM */
#endif