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| author | Alex Shi <alex.shi@intel.com> | 2012-03-03 19:27:27 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2012-03-05 09:19:20 +0100 |
| commit | 901b04450a0ff44d579158b8b0492ce7e66cd442 (patch) | |
| tree | 4db8e537f71b0bbae9c0fcf065335156ec967bde /arch | |
| parent | e24b90b282d73c0654c716d449d91a07ebb8ecaf (diff) | |
| download | linux-901b04450a0ff44d579158b8b0492ce7e66cd442.tar.bz2 | |
x86/numa: Improve internode cache alignment
Currently cache alignment among nodes in the kernel is still 128
bytes on x86 NUMA machines - we got that X86_INTERNODE_CACHE_SHIFT
default from old P4 processors.
But now most modern x86 CPUs use the same size: 64 bytes from L1 to
last level L3. so let's remove the incorrect setting, and directly
use the L1 cache size to do SMP cache line alignment.
This patch saves some memory space on kernel data, and it also
improves the cache locality of kernel data.
The System.map is quite different with/without this change:
before patch after patch
...
000000000000b000 d tlb_vector_| 000000000000b000 d tlb_vector
000000000000b080 d cpu_loops_p| 000000000000b040 d cpu_loops_
...
Signed-off-by: Alex Shi <alex.shi@intel.com>
Cc: asit.k.mallick@intel.com
Link: http://lkml.kernel.org/r/1330774047-18597-1-git-send-email-alex.shi@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/Kconfig.cpu | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu index 3c57033e2211..6443c6f038e8 100644 --- a/arch/x86/Kconfig.cpu +++ b/arch/x86/Kconfig.cpu @@ -303,7 +303,6 @@ config X86_GENERIC config X86_INTERNODE_CACHE_SHIFT int default "12" if X86_VSMP - default "7" if NUMA default X86_L1_CACHE_SHIFT config X86_CMPXCHG |