original_kernel/arch/s390
Heiko Carstens 4bffbb3455 s390/mm: have 16 byte aligned struct pages
Select HAVE_ALIGNED_STRUCT_PAGE on s390, so that the slub allocator can make
use of compare and swap double for lockless updates. This increases the size
of struct page to 64 bytes (instead of 56 bytes), however the performance gain
justifies the increased size:

- now excactly four struct pages fit into a single cache line; the
  case that accessing a struct page causes two cache line loads
  does not exist anymore.
- calculating the offset of a struct page within the memmap array
  is only a simple shift instead of a more expensive multiplication.

A "hackbench 200 process 200" run on a 32 cpu system did show an 8% runtime
improvement.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-13 11:03:09 +01:00
..
appldata
boot
crypto
hypfs
include s390/topology: fix core id vs physical package id mix-up 2012-11-12 16:24:38 +01:00
kernel s390/topology: fix core id vs physical package id mix-up 2012-11-12 16:24:38 +01:00
kvm
lib
math-emu
mm s390/gup: fix access_ok() usage in __get_user_pages_fast() 2012-11-13 11:02:28 +01:00
net
oprofile
Kbuild
Kconfig s390/mm: have 16 byte aligned struct pages 2012-11-13 11:03:09 +01:00
Kconfig.debug
Makefile
defconfig