x86: convert cpuinfo_x86 array to a per_cpu array

cpu_data is currently an array defined using NR_CPUS.  This means that
we overallocate since we will rarely really use maximum configured cpus.
When NR_CPU count is raised to 4096 the size of cpu_data becomes
3,145,728 bytes.

These changes were adopted from the sparc64 (and ia64) code.  An
additional field was added to cpuinfo_x86 to be a non-ambiguous cpu
index.  This corresponds to the index into a cpumask_t as well as the
per_cpu index.  It's used in various places like show_cpuinfo().

cpu_data is defined to be the boot_cpu_data structure for the NON-SMP
case.

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c

@@ -77,7 +77,7 @@ static unsigned int acpi_pstate_strict;
 
 static int check_est_cpu(unsigned int cpuid)
 {
-	struct cpuinfo_x86 *cpu = &cpu_data[cpuid];
+	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 
 	if (cpu->x86_vendor != X86_VENDOR_INTEL ||
 	    !cpu_has(cpu, X86_FEATURE_EST))
@@ -560,7 +560,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	unsigned int cpu = policy->cpu;
 	struct acpi_cpufreq_data *data;
 	unsigned int result = 0;
-	struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
+	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 	struct acpi_processor_performance *perf;
 
 	dprintk("acpi_cpufreq_cpu_init\n");

arch/x86/kernel/cpu/cpufreq/e_powersaver.c

@@ -305,7 +305,7 @@ static struct cpufreq_driver eps_driver = {
 
 static int __init eps_init(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	/* This driver will work only on Centaur C7 processors with
 	 * Enhanced SpeedStep/PowerSaver registers */

arch/x86/kernel/cpu/cpufreq/elanfreq.c

@@ -199,7 +199,7 @@ static int elanfreq_target (struct cpufreq_policy *policy,
 
 static int elanfreq_cpu_init(struct cpufreq_policy *policy)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	unsigned int i;
 	int result;
 
@@ -280,7 +280,7 @@ static struct cpufreq_driver elanfreq_driver = {
 
 static int __init elanfreq_init(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	/* Test if we have the right hardware */
 	if ((c->x86_vendor != X86_VENDOR_AMD) ||

arch/x86/kernel/cpu/cpufreq/longhaul.c

@@ -780,7 +780,7 @@ static int longhaul_setup_southbridge(void)
 
 static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	char *cpuname=NULL;
 	int ret;
 	u32 lo, hi;
@@ -959,7 +959,7 @@ static struct cpufreq_driver longhaul_driver = {
 
 static int __init longhaul_init(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	if (c->x86_vendor != X86_VENDOR_CENTAUR || c->x86 != 6)
 		return -ENODEV;

arch/x86/kernel/cpu/cpufreq/longrun.c

@@ -172,7 +172,7 @@ static unsigned int __init longrun_determine_freqs(unsigned int *low_freq,
 	u32 save_lo, save_hi;
 	u32 eax, ebx, ecx, edx;
 	u32 try_hi;
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	if (!low_freq || !high_freq)
 		return -EINVAL;
@@ -298,7 +298,7 @@ static struct cpufreq_driver longrun_driver = {
  */
 static int __init longrun_init(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	if (c->x86_vendor != X86_VENDOR_TRANSMETA ||
 	    !cpu_has(c, X86_FEATURE_LONGRUN))

arch/x86/kernel/cpu/cpufreq/p4-clockmod.c

@@ -195,7 +195,7 @@ static unsigned int cpufreq_p4_get_frequency(struct cpuinfo_x86 *c)
 
 static int cpufreq_p4_cpu_init(struct cpufreq_policy *policy)
 {
-	struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
+	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 	int cpuid = 0;
 	unsigned int i;
 
@@ -279,7 +279,7 @@ static struct cpufreq_driver p4clockmod_driver = {
 
 static int __init cpufreq_p4_init(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	int ret;
 
 	/*

arch/x86/kernel/cpu/cpufreq/powernow-k6.c

@@ -215,7 +215,7 @@ static struct cpufreq_driver powernow_k6_driver = {
  */
 static int __init powernow_k6_init(void)
 {
-	struct cpuinfo_x86      *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 != 5) ||
 		((c->x86_model != 12) && (c->x86_model != 13)))

arch/x86/kernel/cpu/cpufreq/powernow-k7.c

@@ -114,7 +114,7 @@ static int check_fsb(unsigned int fsbspeed)
 
 static int check_powernow(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	unsigned int maxei, eax, ebx, ecx, edx;
 
 	if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 !=6)) {

arch/x86/kernel/cpu/cpufreq/sc520_freq.c

@@ -102,7 +102,7 @@ static int sc520_freq_target (struct cpufreq_policy *policy,
 
 static int sc520_freq_cpu_init(struct cpufreq_policy *policy)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	int result;
 
 	/* capability check */
@@ -151,7 +151,7 @@ static struct cpufreq_driver sc520_freq_driver = {
 
 static int __init sc520_freq_init(void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	int err;
 
 	/* Test if we have the right hardware */

arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c

@@ -230,7 +230,7 @@ static struct cpu_model models[] =
 
 static int centrino_cpu_init_table(struct cpufreq_policy *policy)
 {
-	struct cpuinfo_x86 *cpu = &cpu_data[policy->cpu];
+	struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu);
 	struct cpu_model *model;
 
 	for(model = models; model->cpu_id != NULL; model++)
@@ -340,7 +340,7 @@ static unsigned int get_cur_freq(unsigned int cpu)
 
 static int centrino_cpu_init(struct cpufreq_policy *policy)
 {
-	struct cpuinfo_x86 *cpu = &cpu_data[policy->cpu];
+	struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu);
 	unsigned freq;
 	unsigned l, h;
 	int ret;
@@ -612,7 +612,7 @@ static struct cpufreq_driver centrino_driver = {
  */
 static int __init centrino_init(void)
 {
-	struct cpuinfo_x86 *cpu = cpu_data;
+	struct cpuinfo_x86 *cpu = &cpu_data(0);
 
 	if (!cpu_has(cpu, X86_FEATURE_EST))
 		return -ENODEV;

arch/x86/kernel/cpu/cpufreq/speedstep-lib.c

@@ -228,7 +228,7 @@ EXPORT_SYMBOL_GPL(speedstep_get_processor_frequency);
 
 unsigned int speedstep_detect_processor (void)
 {
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 	u32 ebx, msr_lo, msr_hi;
 
 	dprintk("x86: %x, model: %x\n", c->x86, c->x86_model);

arch/x86/kernel/cpu/intel_cacheinfo.c

@@ -295,7 +295,7 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
 	unsigned int new_l2 = 0, new_l3 = 0, i; /* Cache sizes from cpuid(4) */
 	unsigned int l2_id = 0, l3_id = 0, num_threads_sharing, index_msb;
 #ifdef CONFIG_X86_HT
-	unsigned int cpu = (c == &boot_cpu_data) ? 0 : (c - cpu_data);
+	unsigned int cpu = c->cpu_index;
 #endif
 
 	if (c->cpuid_level > 3) {
@@ -459,7 +459,7 @@ static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
 	struct _cpuid4_info	*this_leaf, *sibling_leaf;
 	unsigned long num_threads_sharing;
 	int index_msb, i;
-	struct cpuinfo_x86 *c = cpu_data;
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
 
 	this_leaf = CPUID4_INFO_IDX(cpu, index);
 	num_threads_sharing = 1 + this_leaf->eax.split.num_threads_sharing;
@@ -470,8 +470,8 @@ static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
 		index_msb = get_count_order(num_threads_sharing);
 
 		for_each_online_cpu(i) {
-			if (c[i].apicid >> index_msb ==
-			    c[cpu].apicid >> index_msb) {
+			if (cpu_data(i).apicid >> index_msb ==
+			    c->apicid >> index_msb) {
 				cpu_set(i, this_leaf->shared_cpu_map);
 				if (i != cpu && cpuid4_info[i])  {
 					sibling_leaf = CPUID4_INFO_IDX(i, index);

arch/x86/kernel/cpu/proc.c

@@ -85,12 +85,13 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		/* nothing */
 	};
 	struct cpuinfo_x86 *c = v;
-	int i, n = c - cpu_data;
+	int i, n = 0;
 	int fpu_exception;
 
 #ifdef CONFIG_SMP
 	if (!cpu_online(n))
 		return 0;
+	n = c->cpu_index;
 #endif
 	seq_printf(m, "processor\t: %d\n"
 		"vendor_id\t: %s\n"
@@ -175,11 +176,15 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 
 static void *c_start(struct seq_file *m, loff_t *pos)
 {
-	return *pos < NR_CPUS ? cpu_data + *pos : NULL;
+	if (*pos == 0)	/* just in case, cpu 0 is not the first */
+		*pos = first_cpu(cpu_possible_map);
+	if ((*pos) < NR_CPUS && cpu_possible(*pos))
+		return &cpu_data(*pos);
+	return NULL;
 }
 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	++*pos;
+	*pos = next_cpu(*pos, cpu_possible_map);
 	return c_start(m, pos);
 }
 static void c_stop(struct seq_file *m, void *v)