x86: change the default cache size to 64 bytes

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@elte.hu>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
This commit is contained in:
Ingo Molnar 2009-01-12 23:37:16 +01:00
parent 09b3ec7315
commit 0a2a18b721

View File

@ -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