[PATCH 0/3] Virtual huge zero page

Kirill A. Shutemov
2012-09-28T23:36:53Z

From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>

Here's alternative implementation of huge zero page: virtual huge zero
page.

Virtual huge zero page is a PMD table with all entries set to zero page.
H. Peter Anvin asked to evaluate this implementation option.

Pros:
- cache friendly (not yet benchmarked);
- less changes required (if I haven't miss something ;);

Cons:
- increases TLB pressure;
- requires per-arch enabling;
- one more check on handle_mm_fault() path.

At the moment I did only sanity check. Testing is required.

Any opinion?

Kirill A. Shutemov (3):
asm-generic: introduce pmd_special() and pmd_mkspecial()
mm, thp: implement virtual huge zero page
x86: implement HAVE_PMD_SPECAIL

arch/Kconfig | 6 ++++++
arch/x86/Kconfig | 1 +
arch/x86/include/asm/pgtable.h | 14 +++++++++++++-
include/asm-generic/pgtable.h | 12 ++++++++++++
include/linux/mm.h | 8 ++++++++
mm/huge_memory.c | 38 ++++++++++++++++++++++++++++++++++++++
mm/memory.c | 15 ++++++++-------
7 files changed, 86 insertions(+), 8 deletions(-)

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