[RFC RESEND 0/2] ARM: mm: HugeTLB + THP support for non-LPAE

[RFC RESEND 0/2] ARM: mm: HugeTLB + THP support for non-LPAE

[Steve Capper]

Hello,

I'm resending this series again, to try and provoke some discussion on
them.

Cheers,
--
Steve

---  

The following patches bring both HugeTLB support and Transparent
HugePage (THP) support to ARM for 2 levels of paging (i.e. without
LPAE).

This code has been tested on an Arndale board (Exynos 5250), and
is based on 3.11-rc1, with the hugepage simplification patch:
http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/184117.html

HugeTLB and THP support for LPAE has already been merged in 3.11-rc1.

Hugepages can give nice performance boosts to workloads that put
pressure on the TLBs. I've observed uplifts of ~5% to some tasks
just by enabling hugepages via the libhugetlbfs tools. Other
people have observed decent performance boosts when huge pages
are enabled:
http://lists.infradead.org/pipermail/linux-arm-kernel/2013-February/148835.html

I would appreciate any discussion on these patches, as there are
people who have an interest in having huge page support in
non-LPAE kernels.

Steve Capper (2):
  ARM: mm: HugeTLB support for non-LPAE systems.
  ARM: mm: Transparent huge page support for non-LPAE systems.

 arch/arm/Kconfig                      |   4 +-
 arch/arm/include/asm/hugetlb-2level.h | 126 +++++++++++++++++++++++++
 arch/arm/include/asm/hugetlb.h        |   4 +
 arch/arm/include/asm/pgtable-2level.h | 170 ++++++++++++++++++++++++++++++++++
 arch/arm/include/asm/pgtable-3level.h |   6 ++
 arch/arm/include/asm/pgtable.h        |   7 +-
 arch/arm/include/asm/tlb.h            |  10 +-
 arch/arm/kernel/head.S                |  10 +-
 arch/arm/mm/fault.c                   |  13 ---
 arch/arm/mm/fsr-2level.c              |   4 +-
 arch/arm/mm/hugetlbpage.c             |   2 +-
 arch/arm/mm/mmu.c                     |  27 ++++++
 12 files changed, 360 insertions(+), 23 deletions(-)
 create mode 100644 arch/arm/include/asm/hugetlb-2level.h

-- 
1.8.1.4

[RFC RESEND 0/2] ARM: mm: HugeTLB + THP support for non-LPAE

[Steve Capper]

Apologies for the noise, I resent this series but neglected to place
the word "PATCH" in the subject lines of the patches thus the patches
got blocked by the list server. Here is another go at a resend.
---  

The following patches bring both HugeTLB support and Transparent
HugePage (THP) support to ARM for 2 levels of paging (i.e. without
LPAE).

This code has been tested on an Arndale board (Exynos 5250), and
is based on 3.11-rc1, with the hugepage simplification patch:
http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/184117.html

HugeTLB and THP support for LPAE has already been merged in 3.11-rc1.

Hugepages can give nice performance boosts to workloads that put
pressure on the TLBs. I've observed uplifts of ~5% to some tasks
just by enabling hugepages via the libhugetlbfs tools. Other
people have observed decent performance boosts when huge pages
are enabled:
http://lists.infradead.org/pipermail/linux-arm-kernel/2013-February/148835.html

I would appreciate any discussion on these patches, as there are
people who have an interest in having huge page support in
non-LPAE kernels.

Steve Capper (2):
  ARM: mm: HugeTLB support for non-LPAE systems.
  ARM: mm: Transparent huge page support for non-LPAE systems.

 arch/arm/Kconfig                      |   4 +-
 arch/arm/include/asm/hugetlb-2level.h | 126 +++++++++++++++++++++++++
 arch/arm/include/asm/hugetlb.h        |   4 +
 arch/arm/include/asm/pgtable-2level.h | 170 ++++++++++++++++++++++++++++++++++
 arch/arm/include/asm/pgtable-3level.h |   6 ++
 arch/arm/include/asm/pgtable.h        |   7 +-
 arch/arm/include/asm/tlb.h            |  10 +-
 arch/arm/kernel/head.S                |  10 +-
 arch/arm/mm/fault.c                   |  13 ---
 arch/arm/mm/fsr-2level.c              |   4 +-
 arch/arm/mm/hugetlbpage.c             |   2 +-
 arch/arm/mm/mmu.c                     |  27 ++++++
 12 files changed, 360 insertions(+), 23 deletions(-)
 create mode 100644 arch/arm/include/asm/hugetlb-2level.h

-- 
1.8.1.4