[PATCH] x86: change the default cache size to 64 bytes

From: Ingo Molnar
Date: Mon Jan 12 2009 - 17:37:16 EST


Right now the generic cacheline size is 128 bytes - that is wasteful
when structures are aligned, as all modern x86 CPUs have an (effective)
cacheline sizes of 64 bytes.

It was set to 128 bytes due to some cacheline aliasing problems on
older P4 systems, but those are many years old and we dont optimize
for them anymore. (They'll still get the 128 bytes cacheline size if
the kernel is specifically built for Pentium 4)

Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
arch/x86/Kconfig.cpu | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index 8078955..cdf4a96 100644
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -307,10 +307,10 @@ config X86_CMPXCHG

config X86_L1_CACHE_SHIFT
int
- default "7" if MPENTIUM4 || X86_GENERIC || GENERIC_CPU || MPSC
+ default "7" if MPENTIUM4 || MPSC
default "4" if X86_ELAN || M486 || M386 || MGEODEGX1
default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
- default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MVIAC7
+ default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MVIAC7 || X86_GENERIC || GENERIC_CPU

config X86_XADD
def_bool y
--
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