x86: Add cpu_has_topoext

Introduce cpu_has_topoext to check for AMD's CPUID topology extensions
support. It indicates support for
CPUID Fn8000_001D_EAX_x[N:0]-CPUID Fn8000_001E_EDX

See AMD's CPUID Specification, Publication # 25481
(as of Rev. 2.34 September 2010)
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/20121019085813.GD26718@alberichSigned-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/include/asm/cpufeature.h

@@ -311,6 +311,7 @@ extern const char * const x86_power_flags[32];
 #define cpu_has_cx8		boot_cpu_has(X86_FEATURE_CX8)
 #define cpu_has_cx16		boot_cpu_has(X86_FEATURE_CX16)
 #define cpu_has_eager_fpu	boot_cpu_has(X86_FEATURE_EAGER_FPU)
+#define cpu_has_topoext		boot_cpu_has(X86_FEATURE_TOPOEXT)
 
 #if defined(CONFIG_X86_INVLPG) || defined(CONFIG_X86_64)
 # define cpu_has_invlpg		1

arch/x86/kernel/cpu/amd.c

@@ -304,7 +304,7 @@ static void __cpuinit amd_get_topology(struct cpuinfo_x86 *c)
 	int cpu = smp_processor_id();
 
 	/* get information required for multi-node processors */
-	if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
+	if (cpu_has_topoext) {
 		u32 eax, ebx, ecx, edx;
 
 		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);

arch/x86/kernel/smpboot.c

@@ -313,7 +313,7 @@ do {									\
 
 static bool __cpuinit match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
 {
-	if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
+	if (cpu_has_topoext) {
 		int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
 
 		if (c->phys_proc_id == o->phys_proc_id &&