diff options
| author |   Christoph Lameter <clameter@sgi.com> | 2007-10-16 01:24:15 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-16 09:42:51 -0700 |
| commit | 0889eba5b38f66d7d892a167d88284daddd3d43b (patch) | |
| tree | adb578bb92cc18dbf842a9bde67e3861db030557 /arch/x86_64/Kconfig | |
| parent | vmemmap: generify initialisation via helpers (diff) | |
| download | linux-dev-0889eba5b38f66d7d892a167d88284daddd3d43b.tar.xz linux-dev-0889eba5b38f66d7d892a167d88284daddd3d43b.zip | |
x86_64: SPARSEMEM_VMEMMAP 2M page size support
x86_64 uses 2M page table entries to map its 1-1 kernel space. We also
implement the virtual memmap using 2M page table entries. So there is no
additional runtime overhead over FLATMEM, initialisation is slightly more
complex. As FLATMEM still references memory to obtain the mem_map pointer and
SPARSEMEM_VMEMMAP uses a compile time constant, SPARSEMEM_VMEMMAP should be
superior.
With this SPARSEMEM becomes the most efficient way of handling virt_to_page,
pfn_to_page and friends for UP, SMP and NUMA on x86_64.
[apw@shadowen.org: code resplit, style fixups]
[apw@shadowen.org: vmemmap x86_64: ensure end of section memmap is initialised]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andi Kleen <ak@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86_64/Kconfig')
| -rw-r--r-- | arch/x86_64/Kconfig | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig index cf013cb85ea4..8c83dbe4c4d0 100644 --- a/arch/x86_64/Kconfig +++ b/arch/x86_64/Kconfig @@ -409,6 +409,7 @@ config ARCH_DISCONTIGMEM_DEFAULT config ARCH_SPARSEMEM_ENABLE def_bool y depends on (NUMA || EXPERIMENTAL) + select SPARSEMEM_VMEMMAP_ENABLE config ARCH_MEMORY_PROBE def_bool y |