On Wednesday, September 14, 2011 4:02:41 pm Andrew Boyer wrote:
On Sep 14, 2011, at 3:56 PM, Andriy Gapon wrote:
on 14/09/2011 20:59 Andrew Boyer said the following:
When FreeBSD examines the CPU topology using CPUID leaf 11 in
topo_probe_0xb(), it never sets hyperthreading_cpus. At
On Sep 16, 2011, at 8:07 AM, John Baldwin wrote:
I think the right way for an admin to disable HTT is to disable it in the
BIOS so that it doesn't show up in the MADT. Back when we were doing the
MPTABLE_FORCE_HTT hack having a separate tunable made sense (and it possibly
made some limited
When FreeBSD examines the CPU topology using CPUID leaf 11 in topo_probe_0xb(),
it never sets hyperthreading_cpus. At the end of topo_probe_0x4() it sets
hyperthreading_cpus = cpu_logical.
Adding that assignment to line 316 of sys/amd64/amd64/mp_machdep.c seems to do
the right thing on a
on 14/09/2011 20:59 Andrew Boyer said the following:
When FreeBSD examines the CPU topology using CPUID leaf 11 in
topo_probe_0xb(), it never sets hyperthreading_cpus. At the end of
topo_probe_0x4() it sets hyperthreading_cpus = cpu_logical.
Adding that assignment to line 316 of
On Sep 14, 2011, at 3:56 PM, Andriy Gapon wrote:
on 14/09/2011 20:59 Andrew Boyer said the following:
When FreeBSD examines the CPU topology using CPUID leaf 11 in
topo_probe_0xb(), it never sets hyperthreading_cpus. At the end of
topo_probe_0x4() it sets hyperthreading_cpus = cpu_logical.
on 14/09/2011 23:02 Andrew Boyer said the following:
Actually, it's not useless. If you don't set it to something other than zero
the machdep.hyperthreading_allowed tunable doesn't do anything, since it
can't tell which CPUs are actually HTT.
Ah, you are right.
That works correctly with my
