diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2018-06-06 00:57:38 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-08-15 18:12:52 +0200 |
| commit | 63f2c9b0d42f7afcdd698025885dd48bc73a8a5b (patch) | |
| tree | 890fa8e7b22b5f91b9746a2935cf7475313d1307 | |
| parent | 35c67d5baad3e2ab745393cbfeb6c6cc9ac6a334 (diff) | |
x86/cpu/AMD: Evaluate smp_num_siblings early
commit 1e1d7e25fd759eddf96d8ab39d0a90a1979b2d8c upstream
To support force disabling of SMT it's required to know the number of
thread siblings early. amd_get_topology() cannot be called before the APIC
driver is selected, so split out the part which initializes
smp_num_siblings and invoke it from amd_early_init().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index f9b3011a3575..bac32d178fd2 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -315,6 +315,17 @@ static void legacy_fixup_core_id(struct cpuinfo_x86 *c) c->cpu_core_id %= cus_per_node; } + +static void amd_get_topology_early(struct cpuinfo_x86 *c) +{ + if (boot_cpu_has(X86_FEATURE_TOPOEXT)) { + u32 eax, ebx, ecx, edx; + + cpuid(0x8000001e, &eax, &ebx, &ecx, &edx); + smp_num_siblings = ((ebx >> 8) & 0xff) + 1; + } +} + /* * Fixup core topology information for * (1) AMD multi-node processors @@ -668,6 +679,8 @@ static void early_init_amd(struct cpuinfo_x86 *c) clear_cpu_cap(c, X86_FEATURE_SME); } } + + amd_get_topology_early(c); } static void init_amd_k8(struct cpuinfo_x86 *c) |