[NET]: Disable NET_SCH_CLK_CPU for SMP x86 hosts
Opterons with frequency scaling have fully unsynchronized TSCs running at different frequencies, so using TSCs there is not a good idea. Also some other x86 boxes have this problem. gettimeofday should be good enough, so just disable it. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
c8923c6b85
commit
34cb711ba9
|
@ -72,9 +72,11 @@ config NET_SCH_CLK_GETTIMEOFDAY
|
||||||
Choose this if you need a high resolution clock source but can't use
|
Choose this if you need a high resolution clock source but can't use
|
||||||
the CPU's cycle counter.
|
the CPU's cycle counter.
|
||||||
|
|
||||||
|
# don't allow on SMP x86 because they can have unsynchronized TSCs.
|
||||||
|
# gettimeofday is a good alternative
|
||||||
config NET_SCH_CLK_CPU
|
config NET_SCH_CLK_CPU
|
||||||
bool "CPU cycle counter"
|
bool "CPU cycle counter"
|
||||||
depends on X86_TSC || X86_64 || ALPHA || SPARC64 || PPC64 || IA64
|
depends on ((X86_TSC || X86_64) && !SMP) || ALPHA || SPARC64 || PPC64 || IA64
|
||||||
help
|
help
|
||||||
Say Y here if you want to use the CPU's cycle counter as clock source.
|
Say Y here if you want to use the CPU's cycle counter as clock source.
|
||||||
This is a cheap and high resolution clock source, but on some
|
This is a cheap and high resolution clock source, but on some
|
||||||
|
|
Loading…
Reference in New Issue