x86: reduce memory and stack usage in intel_cacheinfo

* Change the following static arrays sized by NR_CPUS to
  per_cpu data variables:

	_cpuid4_info *cpuid4_info[NR_CPUS];
	_index_kobject *index_kobject[NR_CPUS];
	kobject * cache_kobject[NR_CPUS];

* Remove the local NR_CPUS array with a kmalloc'd region in
  show_shared_cpu_map().

Also some minor complaints from checkpatch.pl fixed.

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 40 insertions, 30 deletions

diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 1b889860eb73..2e8b323b34e4 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -129,7 +129,7 @@ struct _cpuid4_info {
         union _cpuid4_leaf_ebx ebx;
         union _cpuid4_leaf_ecx ecx;
         unsigned long size;
-        cpumask_t shared_cpu_map;
+        cpumask_t shared_cpu_map;       /* future?: only cpus/node is needed */
 };
 
 unsigned short                  num_cache_leaves;
@@ -451,8 +451,8 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
 }
 
 /* pointer to _cpuid4_info array (for each cache leaf) */
-static struct _cpuid4_info *cpuid4_info[NR_CPUS];
-#define CPUID4_INFO_IDX(x,y)    (&((cpuid4_info[x])[y]))
+static DEFINE_PER_CPU(struct _cpuid4_info *, cpuid4_info);
+#define CPUID4_INFO_IDX(x, y)    (&((per_cpu(cpuid4_info, x))[y]))
 
 #ifdef CONFIG_SMP
 static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
@@ -474,7 +474,7 @@ static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
                         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])  {
+                                if (i != cpu && per_cpu(cpuid4_info, i))  {
                                         sibling_leaf = CPUID4_INFO_IDX(i, index);
                                         cpu_set(cpu, sibling_leaf->shared_cpu_map);
                                 }
@@ -505,8 +505,8 @@ static void __cpuinit free_cache_attributes(unsigned int cpu)
         for (i = 0; i < num_cache_leaves; i++)
                 cache_remove_shared_cpu_map(cpu, i);
 
-        kfree(cpuid4_info[cpu]);
-        cpuid4_info[cpu] = NULL;
+        kfree(per_cpu(cpuid4_info, cpu));
+        per_cpu(cpuid4_info, cpu) = NULL;
 }
 
 static int __cpuinit detect_cache_attributes(unsigned int cpu)
@@ -519,9 +519,9 @@ static int __cpuinit detect_cache_attributes(unsigned int cpu)
         if (num_cache_leaves == 0)
                 return -ENOENT;
 
-        cpuid4_info[cpu] = kzalloc(
+        per_cpu(cpuid4_info, cpu) = kzalloc(
             sizeof(struct _cpuid4_info) * num_cache_leaves, GFP_KERNEL);
-        if (cpuid4_info[cpu] == NULL)
+        if (per_cpu(cpuid4_info, cpu) == NULL)
                 return -ENOMEM;
 
         oldmask = current->cpus_allowed;
@@ -546,8 +546,8 @@ static int __cpuinit detect_cache_attributes(unsigned int cpu)
 
 out:
         if (retval) {
-                kfree(cpuid4_info[cpu]);
-                cpuid4_info[cpu] = NULL;
+                kfree(per_cpu(cpuid4_info, cpu));
+                per_cpu(cpuid4_info, cpu) = NULL;
         }
 
         return retval;
@@ -561,7 +561,7 @@ out:
 extern struct sysdev_class cpu_sysdev_class; /* from drivers/base/cpu.c */
 
 /* pointer to kobject for cpuX/cache */
-static struct kobject * cache_kobject[NR_CPUS];
+static DEFINE_PER_CPU(struct kobject *, cache_kobject);
 
 struct _index_kobject {
         struct kobject kobj;
@@ -570,8 +570,8 @@ struct _index_kobject {
 };
 
 /* pointer to array of kobjects for cpuX/cache/indexY */
-static struct _index_kobject *index_kobject[NR_CPUS];
-#define INDEX_KOBJECT_PTR(x,y)    (&((index_kobject[x])[y]))
+static DEFINE_PER_CPU(struct _index_kobject *, index_kobject);
+#define INDEX_KOBJECT_PTR(x, y)    (&((per_cpu(index_kobject, x))[y]))
 
 #define show_one_plus(file_name, object, val)                           \
 static ssize_t show_##file_name                                         \
@@ -593,9 +593,16 @@ static ssize_t show_size(struct _cpuid4_info *this_leaf, char *buf)
 
 static ssize_t show_shared_cpu_map(struct _cpuid4_info *this_leaf, char *buf)
 {
-        char mask_str[NR_CPUS];
-        cpumask_scnprintf(mask_str, NR_CPUS, this_leaf->shared_cpu_map);
-        return sprintf(buf, "%s\n", mask_str);
+        int n = 0;
+        int len = cpumask_scnprintf_len(nr_cpu_ids);
+        char *mask_str = kmalloc(len, GFP_KERNEL);
+
+        if (mask_str) {
+                cpumask_scnprintf(mask_str, len, this_leaf->shared_cpu_map);
+                n = sprintf(buf, "%s\n", mask_str);
+                kfree(mask_str);
+        }
+        return n;
 }
 
 static ssize_t show_type(struct _cpuid4_info *this_leaf, char *buf) {
@@ -684,10 +691,10 @@ static struct kobj_type ktype_percpu_entry = {
 
 static void __cpuinit cpuid4_cache_sysfs_exit(unsigned int cpu)
 {
-        kfree(cache_kobject[cpu]);
-        kfree(index_kobject[cpu]);
-        cache_kobject[cpu] = NULL;
-        index_kobject[cpu] = NULL;
+        kfree(per_cpu(cache_kobject, cpu));
+        kfree(per_cpu(index_kobject, cpu));
+        per_cpu(cache_kobject, cpu) = NULL;
+        per_cpu(index_kobject, cpu) = NULL;
         free_cache_attributes(cpu);
 }
 
@@ -703,13 +710,14 @@ static int __cpuinit cpuid4_cache_sysfs_init(unsigned int cpu)
                 return err;
 
         /* Allocate all required memory */
-        cache_kobject[cpu] = kzalloc(sizeof(struct kobject), GFP_KERNEL);
-        if (unlikely(cache_kobject[cpu] == NULL))
+        per_cpu(cache_kobject, cpu) =
+                kzalloc(sizeof(struct kobject), GFP_KERNEL);
+        if (unlikely(per_cpu(cache_kobject, cpu) == NULL))
                 goto err_out;
 
-        index_kobject[cpu] = kzalloc(
+        per_cpu(index_kobject, cpu) = kzalloc(
             sizeof(struct _index_kobject ) * num_cache_leaves, GFP_KERNEL);
-        if (unlikely(index_kobject[cpu] == NULL))
+        if (unlikely(per_cpu(index_kobject, cpu) == NULL))
                 goto err_out;
 
         return 0;
@@ -733,7 +741,8 @@ static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
         if (unlikely(retval < 0))
                 return retval;
 
-        retval = kobject_init_and_add(cache_kobject[cpu], &ktype_percpu_entry,
+        retval = kobject_init_and_add(per_cpu(cache_kobject, cpu),
+                                      &ktype_percpu_entry,
                                       &sys_dev->kobj, "%s", "cache");
         if (retval < 0) {
                 cpuid4_cache_sysfs_exit(cpu);
@@ -745,13 +754,14 @@ static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
                 this_object->cpu = cpu;
                 this_object->index = i;
                 retval = kobject_init_and_add(&(this_object->kobj),
-                                              &ktype_cache, cache_kobject[cpu],
+                                              &ktype_cache,
+                                              per_cpu(cache_kobject, cpu),
                                               "index%1lu", i);
                 if (unlikely(retval)) {
                         for (j = 0; j < i; j++) {
                                 kobject_put(&(INDEX_KOBJECT_PTR(cpu,j)->kobj));
                         }
-                        kobject_put(cache_kobject[cpu]);
+                        kobject_put(per_cpu(cache_kobject, cpu));
                         cpuid4_cache_sysfs_exit(cpu);
                         break;
                 }
@@ -760,7 +770,7 @@ static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
         if (!retval)
                 cpu_set(cpu, cache_dev_map);
 
-        kobject_uevent(cache_kobject[cpu], KOBJ_ADD);
+        kobject_uevent(per_cpu(cache_kobject, cpu), KOBJ_ADD);
         return retval;
 }
 
@@ -769,7 +779,7 @@ static void __cpuinit cache_remove_dev(struct sys_device * sys_dev)
         unsigned int cpu = sys_dev->id;
         unsigned long i;
 
-        if (cpuid4_info[cpu] == NULL)
+        if (per_cpu(cpuid4_info, cpu) == NULL)
                 return;
         if (!cpu_isset(cpu, cache_dev_map))
                 return;
@@ -777,7 +787,7 @@ static void __cpuinit cache_remove_dev(struct sys_device * sys_dev)
 
         for (i = 0; i < num_cache_leaves; i++)
                 kobject_put(&(INDEX_KOBJECT_PTR(cpu,i)->kobj));
-        kobject_put(cache_kobject[cpu]);
+        kobject_put(per_cpu(cache_kobject, cpu));
         cpuid4_cache_sysfs_exit(cpu);
 }