x86: reduce stack usage in init_intel_cacheinfo

Impact: reduce stack usage.

init_intel_cacheinfo() does not use the cpumask so define a subset
of struct _cpuid4_info (_cpuid4_info_regs) that can be used instead.

Signed-off-by: Mike Travis <travis@sgi.com>

1 files changed, 44 insertions, 19 deletions

diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 48533d77be78..58527a9fc404 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -132,7 +132,16 @@ struct _cpuid4_info {
         union _cpuid4_leaf_ecx ecx;
         unsigned long size;
         unsigned long can_disable;
-        cpumask_t shared_cpu_map;       /* future?: only cpus/node is needed */
+        DECLARE_BITMAP(shared_cpu_map, NR_CPUS);
+};
+
+/* subset of above _cpuid4_info w/o shared_cpu_map */
+struct _cpuid4_info_regs {
+        union _cpuid4_leaf_eax eax;
+        union _cpuid4_leaf_ebx ebx;
+        union _cpuid4_leaf_ecx ecx;
+        unsigned long size;
+        unsigned long can_disable;
 };
 
 #ifdef CONFIG_PCI
@@ -263,7 +272,7 @@ amd_cpuid4(int leaf, union _cpuid4_leaf_eax *eax,
 }
 
 static void __cpuinit
-amd_check_l3_disable(int index, struct _cpuid4_info *this_leaf)
+amd_check_l3_disable(int index, struct _cpuid4_info_regs *this_leaf)
 {
         if (index < 3)
                 return;
@@ -271,7 +280,8 @@ amd_check_l3_disable(int index, struct _cpuid4_info *this_leaf)
 }
 
 static int
-__cpuinit cpuid4_cache_lookup(int index, struct _cpuid4_info *this_leaf)
+__cpuinit cpuid4_cache_lookup_regs(int index,
+                                   struct _cpuid4_info_regs *this_leaf)
 {
         union _cpuid4_leaf_eax  eax;
         union _cpuid4_leaf_ebx  ebx;
@@ -299,6 +309,15 @@ __cpuinit cpuid4_cache_lookup(int index, struct _cpuid4_info *this_leaf)
         return 0;
 }
 
+static int
+__cpuinit cpuid4_cache_lookup(int index, struct _cpuid4_info *this_leaf)
+{
+        struct _cpuid4_info_regs *leaf_regs =
+                (struct _cpuid4_info_regs *)this_leaf;
+
+        return cpuid4_cache_lookup_regs(index, leaf_regs);
+}
+
 static int __cpuinit find_num_cache_leaves(void)
 {
         unsigned int            eax, ebx, ecx, edx;
@@ -338,11 +357,10 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
                  * parameters cpuid leaf to find the cache details
                  */
                 for (i = 0; i < num_cache_leaves; i++) {
-                        struct _cpuid4_info this_leaf;
-
+                        struct _cpuid4_info_regs this_leaf;
                         int retval;
 
-                        retval = cpuid4_cache_lookup(i, &this_leaf);
+                        retval = cpuid4_cache_lookup_regs(i, &this_leaf);
                         if (retval >= 0) {
                                 switch(this_leaf.eax.split.level) {
                                     case 1:
@@ -491,17 +509,20 @@ static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
         num_threads_sharing = 1 + this_leaf->eax.split.num_threads_sharing;
 
         if (num_threads_sharing == 1)
-                cpu_set(cpu, this_leaf->shared_cpu_map);
+                cpumask_set_cpu(cpu, to_cpumask(this_leaf->shared_cpu_map));
         else {
                 index_msb = get_count_order(num_threads_sharing);
 
                 for_each_online_cpu(i) {
                         if (cpu_data(i).apicid >> index_msb ==
                             c->apicid >> index_msb) {
-                                cpu_set(i, this_leaf->shared_cpu_map);
+                                cpumask_set_cpu(i,
+                                        to_cpumask(this_leaf->shared_cpu_map));
                                 if (i != cpu && per_cpu(cpuid4_info, i))  {
-                                        sibling_leaf = CPUID4_INFO_IDX(i, index);
-                                        cpu_set(cpu, sibling_leaf->shared_cpu_map);
+                                        sibling_leaf =
+                                                CPUID4_INFO_IDX(i, index);
+                                        cpumask_set_cpu(cpu, to_cpumask(
+                                                sibling_leaf->shared_cpu_map));
                                 }
                         }
                 }
@@ -513,9 +534,10 @@ static void __cpuinit cache_remove_shared_cpu_map(unsigned int cpu, int index)
         int sibling;
 
         this_leaf = CPUID4_INFO_IDX(cpu, index);
-        for_each_cpu_mask_nr(sibling, this_leaf->shared_cpu_map) {
+        for_each_cpu(sibling, to_cpumask(this_leaf->shared_cpu_map)) {
                 sibling_leaf = CPUID4_INFO_IDX(sibling, index);
-                cpu_clear(cpu, sibling_leaf->shared_cpu_map);
+                cpumask_clear_cpu(cpu,
+                                  to_cpumask(sibling_leaf->shared_cpu_map));
         }
 }
 #else
@@ -620,8 +642,9 @@ static ssize_t show_shared_cpu_map_func(struct _cpuid4_info *this_leaf,
         int n = 0;
 
         if (len > 1) {
-                cpumask_t *mask = &this_leaf->shared_cpu_map;
+                const struct cpumask *mask;
 
+                mask = to_cpumask(this_leaf->shared_cpu_map);
                 n = type?
                         cpulist_scnprintf(buf, len-2, mask) :
                         cpumask_scnprintf(buf, len-2, mask);
@@ -684,7 +707,8 @@ static struct pci_dev *get_k8_northbridge(int node)
 
 static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf)
 {
-        int node = cpu_to_node(first_cpu(this_leaf->shared_cpu_map));
+        const struct cpumask *mask = to_cpumask(this_leaf->shared_cpu_map);
+        int node = cpu_to_node(cpumask_first(mask));
         struct pci_dev *dev = NULL;
         ssize_t ret = 0;
         int i;
@@ -718,7 +742,8 @@ static ssize_t
 store_cache_disable(struct _cpuid4_info *this_leaf, const char *buf,
                     size_t count)
 {
-        int node = cpu_to_node(first_cpu(this_leaf->shared_cpu_map));
+        const struct cpumask *mask = to_cpumask(this_leaf->shared_cpu_map);
+        int node = cpu_to_node(cpumask_first(mask));
         struct pci_dev *dev = NULL;
         unsigned int ret, index, val;
 
@@ -863,7 +888,7 @@ err_out:
         return -ENOMEM;
 }
 
-static cpumask_t cache_dev_map = CPU_MASK_NONE;
+static DECLARE_BITMAP(cache_dev_map, NR_CPUS);
 
 /* Add/Remove cache interface for CPU device */
 static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
@@ -903,7 +928,7 @@ static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
                 }
                 kobject_uevent(&(this_object->kobj), KOBJ_ADD);
         }
-        cpu_set(cpu, cache_dev_map);
+        cpumask_set_cpu(cpu, to_cpumask(cache_dev_map));
 
         kobject_uevent(per_cpu(cache_kobject, cpu), KOBJ_ADD);
         return 0;
@@ -916,9 +941,9 @@ static void __cpuinit cache_remove_dev(struct sys_device * sys_dev)
 
         if (per_cpu(cpuid4_info, cpu) == NULL)
                 return;
-        if (!cpu_isset(cpu, cache_dev_map))
+        if (!cpumask_test_cpu(cpu, to_cpumask(cache_dev_map)))
                 return;
-        cpu_clear(cpu, cache_dev_map);
+        cpumask_clear_cpu(cpu, to_cpumask(cache_dev_map));
 
         for (i = 0; i < num_cache_leaves; i++)
                 kobject_put(&(INDEX_KOBJECT_PTR(cpu,i)->kobj));