x86: convert cpu_llc_id to be a per cpu variable

Convert cpu_llc_id from a static array sized by NR_CPUS to a per_cpu
variable. This saves sizeof(cpu_llc_id) * NR unused cpus.  Access is
mostly from startup and CPU HOTPLUG functions.

Note there's an additional change of the type of cpu_llc_id from int to
u8 for ARCH i386 to correspond with the same type in ARCH x86_64.
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/cpu/intel_cacheinfo.c

@@ -417,14 +417,14 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
 	if (new_l2) {
 		l2 = new_l2;
 #ifdef CONFIG_X86_HT
-		cpu_llc_id[cpu] = l2_id;
+		per_cpu(cpu_llc_id, cpu) = l2_id;
 #endif
 	}
 
 	if (new_l3) {
 		l3 = new_l3;
 #ifdef CONFIG_X86_HT
-		cpu_llc_id[cpu] = l3_id;
+		per_cpu(cpu_llc_id, cpu) = l3_id;
 #endif
 	}
 

arch/x86/kernel/smpboot_32.c

@@ -67,7 +67,7 @@ int smp_num_siblings = 1;
 EXPORT_SYMBOL(smp_num_siblings);
 
 /* Last level cache ID of each logical CPU */
-int cpu_llc_id[NR_CPUS] __cpuinitdata = {[0 ... NR_CPUS-1] = BAD_APICID};
+DEFINE_PER_CPU(u8, cpu_llc_id) = BAD_APICID;
 
 /* representing HT siblings of each logical CPU */
 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map);
@@ -348,8 +348,8 @@ void __cpuinit set_cpu_sibling_map(int cpu)
 	}
 
 	for_each_cpu_mask(i, cpu_sibling_setup_map) {
-		if (cpu_llc_id[cpu] != BAD_APICID &&
-		    cpu_llc_id[cpu] == cpu_llc_id[i]) {
+		if (per_cpu(cpu_llc_id, cpu) != BAD_APICID &&
+		    per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i)) {
 			cpu_set(i, c[cpu].llc_shared_map);
 			cpu_set(cpu, c[i].llc_shared_map);
 		}

arch/x86/kernel/smpboot_64.c

@@ -65,7 +65,7 @@ int smp_num_siblings = 1;
 EXPORT_SYMBOL(smp_num_siblings);
 
 /* Last level cache ID of each logical CPU */
-u8 cpu_llc_id[NR_CPUS] __cpuinitdata  = {[0 ... NR_CPUS-1] = BAD_APICID};
+DEFINE_PER_CPU(u8, cpu_llc_id) = BAD_APICID;
 
 /* Bitmask of currently online CPUs */
 cpumask_t cpu_online_map __read_mostly;
@@ -283,8 +283,8 @@ static inline void set_cpu_sibling_map(int cpu)
 	}
 
 	for_each_cpu_mask(i, cpu_sibling_setup_map) {
-		if (cpu_llc_id[cpu] != BAD_APICID &&
-		    cpu_llc_id[cpu] == cpu_llc_id[i]) {
+		if (per_cpu(cpu_llc_id, cpu) != BAD_APICID &&
+		    per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i)) {
 			cpu_set(i, c[cpu].llc_shared_map);
 			cpu_set(cpu, c[i].llc_shared_map);
 		}

include/asm-x86/processor_32.h

@@ -110,7 +110,11 @@ extern struct cpuinfo_x86 cpu_data[];
 #define current_cpu_data boot_cpu_data
 #endif
 
-extern	int cpu_llc_id[NR_CPUS];
+/*
+ * the following now lives in the per cpu area:
+ * extern	int cpu_llc_id[NR_CPUS];
+ */
+DECLARE_PER_CPU(u8, cpu_llc_id);
 extern char ignore_fpu_irq;
 
 void __init cpu_detect(struct cpuinfo_x86 *c);

include/asm-x86/smp_64.h

@@ -49,7 +49,7 @@ extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *),
  */
 DECLARE_PER_CPU(cpumask_t, cpu_sibling_map);
 DECLARE_PER_CPU(cpumask_t, cpu_core_map);
-extern u8 cpu_llc_id[NR_CPUS];
+DECLARE_PER_CPU(u8, cpu_llc_id);
 
 #define SMP_TRAMPOLINE_BASE 0x6000
 
@@ -121,6 +121,7 @@ static __inline int logical_smp_processor_id(void)
 #ifdef CONFIG_SMP
 #define cpu_physical_id(cpu)		per_cpu(x86_cpu_to_apicid, cpu)
 #else
+extern unsigned int boot_cpu_id;
 #define cpu_physical_id(cpu)		boot_cpu_id
 #endif /* !CONFIG_SMP */
 #endif