x86/cpu: Track legacy CPU model data only on 32-bit kernels

struct cpu_dev's c_models is only ever set inside CONFIG_X86_32
conditionals (or code that's being built for 32-bit only), so
there's no use of reserving the (empty) space for the model
names in a 64-bit kernel.

Similarly, c_size_cache is only used in the #else of a
CONFIG_X86_64 conditional, so reserving space for (and in one
case even initializing) that field is pointless for 64-bit
kernels too.

While moving both fields to the end of the structure, I also
noticed that:

 - the c_models array size was one too small, potentially causing
   table_lookup_model() to return garbage on Intel CPUs (intel.c's
   instance was lacking the sentinel with family being zero), so the
   patch bumps that by one,

 - c_models' vendor sub-field was unused (and anyway redundant
   with the base structure's c_x86_vendor field), so the patch deletes it.

Also rename the legacy fields so that their legacy nature stands out
and comment their declarations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/5265036802000078000FC4DB@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 2793d1f095a2..9ada0b37ae07 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -346,7 +346,8 @@ static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
 /* Look up CPU names by table lookup. */
 static const char *table_lookup_model(struct cpuinfo_x86 *c)
 {
-	const struct cpu_model_info *info;
+#ifdef CONFIG_X86_32
+	const struct legacy_cpu_model_info *info;
 
 	if (c->x86_model >= 16)
 		return NULL;	/* Range check */
@@ -354,13 +355,14 @@ static const char *table_lookup_model(struct cpuinfo_x86 *c)
 	if (!this_cpu)
 		return NULL;
 
-	info = this_cpu->c_models;
+	info = this_cpu->legacy_models;
 
-	while (info && info->family) {
+	while (info->family) {
 		if (info->family == c->x86)
 			return info->model_names[c->x86_model];
 		info++;
 	}
+#endif
 	return NULL;		/* Not found */
 }
 
@@ -450,8 +452,8 @@ void cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
 	c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
 #else
 	/* do processor-specific cache resizing */
-	if (this_cpu->c_size_cache)
-		l2size = this_cpu->c_size_cache(c, l2size);
+	if (this_cpu->legacy_cache_size)
+		l2size = this_cpu->legacy_cache_size(c, l2size);
 
 	/* Allow user to override all this if necessary. */
 	if (cachesize_override != -1)