[PATCH 15 of 66] config_transparent_hugepage

Andrea Arcangeli
2010-11-03T15:40:19Z

From: Andrea Arcangeli <aarcange@redhat.com>

Add config option.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
---

diff --git a/fs/Kconfig b/fs/Kconfig
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -147,7 +147,7 @@ config HUGETLBFS
If unsure, say N.

config HUGETLB_PAGE
- def_bool HUGETLBFS
+ def_bool HUGETLBFS || TRANSPARENT_HUGEPAGE

source "fs/configfs/Kconfig"

diff --git a/mm/Kconfig b/mm/Kconfig
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -302,6 +302,20 @@ config NOMMU_INITIAL_TRIM_EXCESS

See Documentation/nommu-mmap.txt for more information.

+config TRANSPARENT_HUGEPAGE
+ bool "Transparent Hugepage Support" if EMBEDDED
+ depends on X86_64 && MMU
+ default y
+ help
+ Transparent Hugepages allows the kernel to use huge pages and
+ huge tlb transparently to the applications whenever possible.
+ This feature can improve computing performance to certain
+ applications by speeding up page faults during memory
+ allocation, by reducing the number of tlb misses and by speeding
+ up the pagetable walking.
+
+ If memory constrained on embedded, you may want to say N.
+
#
# UP and nommu archs use km based percpu allocator
#