sched: get rid of boutique sched.c allocations, use cpumask_var_t.

Impact: use new general API

Using lots of allocs rather than one big alloc is less efficient, but
who cares for this setup function?

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 55 insertions, 84 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index e59978eead17..0dc9d5752d68 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -7263,48 +7263,6 @@ SD_INIT_FUNC(CPU)
  SD_INIT_FUNC(MC)
 #endif
 
-/*
- * To minimize stack usage kmalloc room for cpumasks and share the
- * space as the usage in build_sched_domains() dictates.  Used only
- * if the amount of space is significant.
- */
-struct allmasks {
-        cpumask_t tmpmask;                      /* make this one first */
-        union {
-                cpumask_t nodemask;
-                cpumask_t this_sibling_map;
-                cpumask_t this_core_map;
-        };
-        cpumask_t send_covered;
-
-#ifdef CONFIG_NUMA
-        cpumask_t domainspan;
-        cpumask_t covered;
-        cpumask_t notcovered;
-#endif
-};
-
-#if     NR_CPUS > 128
-#define SCHED_CPUMASK_DECLARE(v)        struct allmasks *v
-static inline void sched_cpumask_alloc(struct allmasks **masks)
-{
-        *masks = kmalloc(sizeof(**masks), GFP_KERNEL);
-}
-static inline void sched_cpumask_free(struct allmasks *masks)
-{
-        kfree(masks);
-}
-#else
-#define SCHED_CPUMASK_DECLARE(v)        struct allmasks _v, *v = &_v
-static inline void sched_cpumask_alloc(struct allmasks **masks)
-{ }
-static inline void sched_cpumask_free(struct allmasks *masks)
-{ }
-#endif
-
-#define SCHED_CPUMASK_VAR(v, a)         cpumask_t *v = (cpumask_t *) \
-                        ((unsigned long)(a) + offsetof(struct allmasks, v))
-
 static int default_relax_domain_level = -1;
 
 static int __init setup_relax_domain_level(char *str)
@@ -7347,14 +7305,35 @@ static void set_domain_attribute(struct sched_domain *sd,
 static int __build_sched_domains(const cpumask_t *cpu_map,
                                  struct sched_domain_attr *attr)
 {
-        int i;
+        int i, err = -ENOMEM;
         struct root_domain *rd;
-        SCHED_CPUMASK_DECLARE(allmasks);
-        cpumask_t *tmpmask;
+        cpumask_var_t nodemask, this_sibling_map, this_core_map, send_covered,
+                tmpmask;
 #ifdef CONFIG_NUMA
+        cpumask_var_t domainspan, covered, notcovered;
         struct sched_group **sched_group_nodes = NULL;
         int sd_allnodes = 0;
 
+        if (!alloc_cpumask_var(&domainspan, GFP_KERNEL))
+                goto out;
+        if (!alloc_cpumask_var(&covered, GFP_KERNEL))
+                goto free_domainspan;
+        if (!alloc_cpumask_var(&notcovered, GFP_KERNEL))
+                goto free_covered;
+#endif
+
+        if (!alloc_cpumask_var(&nodemask, GFP_KERNEL))
+                goto free_notcovered;
+        if (!alloc_cpumask_var(&this_sibling_map, GFP_KERNEL))
+                goto free_nodemask;
+        if (!alloc_cpumask_var(&this_core_map, GFP_KERNEL))
+                goto free_this_sibling_map;
+        if (!alloc_cpumask_var(&send_covered, GFP_KERNEL))
+                goto free_this_core_map;
+        if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
+                goto free_send_covered;
+
+#ifdef CONFIG_NUMA
         /*
          * Allocate the per-node list of sched groups
          */
@@ -7362,33 +7341,16 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                                     GFP_KERNEL);
         if (!sched_group_nodes) {
                 printk(KERN_WARNING "Can not alloc sched group node list\n");
-                return -ENOMEM;
+                goto free_tmpmask;
         }
 #endif
 
         rd = alloc_rootdomain();
         if (!rd) {
                 printk(KERN_WARNING "Cannot alloc root domain\n");
-#ifdef CONFIG_NUMA
-                kfree(sched_group_nodes);
-#endif
-                return -ENOMEM;
+                goto free_sched_groups;
         }
 
-        /* get space for all scratch cpumask variables */
-        sched_cpumask_alloc(&allmasks);
-        if (!allmasks) {
-                printk(KERN_WARNING "Cannot alloc cpumask array\n");
-                kfree(rd);
-#ifdef CONFIG_NUMA
-                kfree(sched_group_nodes);
-#endif
-                return -ENOMEM;
-        }
-
-        tmpmask = (cpumask_t *)allmasks;
-
-
 #ifdef CONFIG_NUMA
         sched_group_nodes_bycpu[first_cpu(*cpu_map)] = sched_group_nodes;
 #endif
@@ -7398,7 +7360,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
          */
         for_each_cpu(i, cpu_map) {
                 struct sched_domain *sd = NULL, *p;
-                SCHED_CPUMASK_VAR(nodemask, allmasks);
 
                 *nodemask = node_to_cpumask(cpu_to_node(i));
                 cpus_and(*nodemask, *nodemask, *cpu_map);
@@ -7464,9 +7425,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
 #ifdef CONFIG_SCHED_SMT
         /* Set up CPU (sibling) groups */
         for_each_cpu(i, cpu_map) {
-                SCHED_CPUMASK_VAR(this_sibling_map, allmasks);
-                SCHED_CPUMASK_VAR(send_covered, allmasks);
-
                 *this_sibling_map = per_cpu(cpu_sibling_map, i);
                 cpus_and(*this_sibling_map, *this_sibling_map, *cpu_map);
                 if (i != first_cpu(*this_sibling_map))
@@ -7481,9 +7439,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
 #ifdef CONFIG_SCHED_MC
         /* Set up multi-core groups */
         for_each_cpu(i, cpu_map) {
-                SCHED_CPUMASK_VAR(this_core_map, allmasks);
-                SCHED_CPUMASK_VAR(send_covered, allmasks);
-
                 *this_core_map = cpu_coregroup_map(i);
                 cpus_and(*this_core_map, *this_core_map, *cpu_map);
                 if (i != first_cpu(*this_core_map))
@@ -7497,9 +7452,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
 
         /* Set up physical groups */
         for (i = 0; i < nr_node_ids; i++) {
-                SCHED_CPUMASK_VAR(nodemask, allmasks);
-                SCHED_CPUMASK_VAR(send_covered, allmasks);
-
                 *nodemask = node_to_cpumask(i);
                 cpus_and(*nodemask, *nodemask, *cpu_map);
                 if (cpus_empty(*nodemask))
@@ -7513,8 +7465,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
 #ifdef CONFIG_NUMA
         /* Set up node groups */
         if (sd_allnodes) {
-                SCHED_CPUMASK_VAR(send_covered, allmasks);
-
                 init_sched_build_groups(cpu_map, cpu_map,
                                         &cpu_to_allnodes_group,
                                         send_covered, tmpmask);
@@ -7523,9 +7473,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
         for (i = 0; i < nr_node_ids; i++) {
                 /* Set up node groups */
                 struct sched_group *sg, *prev;
-                SCHED_CPUMASK_VAR(nodemask, allmasks);
-                SCHED_CPUMASK_VAR(domainspan, allmasks);
-                SCHED_CPUMASK_VAR(covered, allmasks);
                 int j;
 
                 *nodemask = node_to_cpumask(i);
@@ -7560,7 +7507,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                 prev = sg;
 
                 for (j = 0; j < nr_node_ids; j++) {
-                        SCHED_CPUMASK_VAR(notcovered, allmasks);
                         int n = (i + j) % nr_node_ids;
                         node_to_cpumask_ptr(pnodemask, n);
 
@@ -7639,15 +7585,40 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                 cpu_attach_domain(sd, rd, i);
         }
 
-        sched_cpumask_free(allmasks);
-        return 0;
+        err = 0;
+
+free_tmpmask:
+        free_cpumask_var(tmpmask);
+free_send_covered:
+        free_cpumask_var(send_covered);
+free_this_core_map:
+        free_cpumask_var(this_core_map);
+free_this_sibling_map:
+        free_cpumask_var(this_sibling_map);
+free_nodemask:
+        free_cpumask_var(nodemask);
+free_notcovered:
+#ifdef CONFIG_NUMA
+        free_cpumask_var(notcovered);
+free_covered:
+        free_cpumask_var(covered);
+free_domainspan:
+        free_cpumask_var(domainspan);
+out:
+#endif
+        return err;
+
+free_sched_groups:
+#ifdef CONFIG_NUMA
+        kfree(sched_group_nodes);
+#endif
+        goto free_tmpmask;
 
 #ifdef CONFIG_NUMA
 error:
         free_sched_groups(cpu_map, tmpmask);
-        sched_cpumask_free(allmasks);
         kfree(rd);
-        return -ENOMEM;
+        goto free_tmpmask;
 #endif
 }