[PATCH] x86_64: Remove unused AMD K8 C stepping flag

X86_FEATURE_K8_C was a synthetic Linux CPUID flag that was used for some
code optimizations in Opteron C stepping or later. But support for pre C
stepping optimizations has been removed, so this isn't needed anymore.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/x86_64/kernel/setup.c

@@ -879,7 +879,6 @@ static void __init amd_detect_cmp(struct cpuinfo_x86 *c)
 static int __init init_amd(struct cpuinfo_x86 *c)
 {
 	int r;
-	int level;
 
 #ifdef CONFIG_SMP
 	unsigned long value;
@@ -902,11 +901,6 @@ static int __init init_amd(struct cpuinfo_x86 *c)
 	   3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway */
 	clear_bit(0*32+31, &c->x86_capability);
 	
-	/* C-stepping K8? */
-	level = cpuid_eax(1);
-	if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
-		set_bit(X86_FEATURE_K8_C, &c->x86_capability);
-
 	r = get_model_name(c);
 	if (!r) { 
 		switch (c->x86) { 

include/asm-x86_64/cpufeature.h

@@ -61,7 +61,7 @@
 #define X86_FEATURE_K6_MTRR	(3*32+ 1) /* AMD K6 nonstandard MTRRs */
 #define X86_FEATURE_CYRIX_ARR	(3*32+ 2) /* Cyrix ARRs (= MTRRs) */
 #define X86_FEATURE_CENTAUR_MCR	(3*32+ 3) /* Centaur MCRs (= MTRRs) */
-#define X86_FEATURE_K8_C	(3*32+ 4) /* C stepping K8 */
+/* 4 free */
 #define X86_FEATURE_CONSTANT_TSC (3*32+5) /* TSC runs at constant rate */
 #define X86_FEATURE_SYNC_RDTSC  (3*32+6)  /* RDTSC syncs CPU core */