sched: wrap sched_group and sched_domain cpumask accesses.

Impact: trivial wrap of member accesses

This eases the transition in the next patch.

We also get rid of a temporary cpumask in find_idlest_cpu() thanks to
for_each_cpu_and, and sched_balance_self() due to getting weight before
setting sd to NULL.

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

5 files changed, 73 insertions, 67 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4ce5c603c51..2b95aa9f779 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -786,6 +786,11 @@ struct sched_group {
         u32 reciprocal_cpu_power;
 };
 
+static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
+{
+        return &sg->cpumask;
+}
+
 enum sched_domain_level {
         SD_LV_NONE = 0,
         SD_LV_SIBLING,
@@ -866,6 +871,11 @@ struct sched_domain {
 #endif
 };
 
+static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
+{
+        return &sd->span;
+}
+
 extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
                                     struct sched_domain_attr *dattr_new);
 extern int arch_reinit_sched_domains(void);
diff --git a/kernel/sched.c b/kernel/sched.c
index a2de33d0534..575f38acf4d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1501,7 +1501,7 @@ static int tg_shares_up(struct task_group *tg, void *data)
         struct sched_domain *sd = data;
         int i;
 
-        for_each_cpu_mask(i, sd->span) {
+        for_each_cpu(i, sched_domain_span(sd)) {
                 /*
                  * If there are currently no tasks on the cpu pretend there
                  * is one of average load so that when a new task gets to
@@ -1522,7 +1522,7 @@ static int tg_shares_up(struct task_group *tg, void *data)
         if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE))
                 shares = tg->shares;
 
-        for_each_cpu_mask(i, sd->span)
+        for_each_cpu(i, sched_domain_span(sd))
                 update_group_shares_cpu(tg, i, shares, rq_weight);
 
         return 0;
@@ -2053,15 +2053,17 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p, int this_cpu)
                 int i;
 
                 /* Skip over this group if it has no CPUs allowed */
-                if (!cpus_intersects(group->cpumask, p->cpus_allowed))
+                if (!cpumask_intersects(sched_group_cpus(group),
+                                        &p->cpus_allowed))
                         continue;
 
-                local_group = cpu_isset(this_cpu, group->cpumask);
+                local_group = cpumask_test_cpu(this_cpu,
+                                               sched_group_cpus(group));
 
                 /* Tally up the load of all CPUs in the group */
                 avg_load = 0;
 
-                for_each_cpu(i, &group->cpumask) {
+                for_each_cpu(i, sched_group_cpus(group)) {
                         /* Bias balancing toward cpus of our domain */
                         if (local_group)
                                 load = source_load(i, load_idx);
@@ -2093,17 +2095,14 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p, int this_cpu)
  * find_idlest_cpu - find the idlest cpu among the cpus in group.
  */
 static int
-find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu,
-                cpumask_t *tmp)
+find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
 {
         unsigned long load, min_load = ULONG_MAX;
         int idlest = -1;
         int i;
 
         /* Traverse only the allowed CPUs */
-        cpus_and(*tmp, group->cpumask, p->cpus_allowed);
-
-        for_each_cpu(i, tmp) {
+        for_each_cpu_and(i, sched_group_cpus(group), &p->cpus_allowed) {
                 load = weighted_cpuload(i);
 
                 if (load < min_load || (load == min_load && i == this_cpu)) {
@@ -2145,7 +2144,6 @@ static int sched_balance_self(int cpu, int flag)
                 update_shares(sd);
 
         while (sd) {
-                cpumask_t span, tmpmask;
                 struct sched_group *group;
                 int new_cpu, weight;
 
@@ -2154,14 +2152,13 @@ static int sched_balance_self(int cpu, int flag)
                         continue;
                 }
 
-                span = sd->span;
                 group = find_idlest_group(sd, t, cpu);
                 if (!group) {
                         sd = sd->child;
                         continue;
                 }
 
-                new_cpu = find_idlest_cpu(group, t, cpu, &tmpmask);
+                new_cpu = find_idlest_cpu(group, t, cpu);
                 if (new_cpu == -1 || new_cpu == cpu) {
                         /* Now try balancing at a lower domain level of cpu */
                         sd = sd->child;
@@ -2170,10 +2167,10 @@ static int sched_balance_self(int cpu, int flag)
 
                 /* Now try balancing at a lower domain level of new_cpu */
                 cpu = new_cpu;
+                weight = cpumask_weight(sched_domain_span(sd));
                 sd = NULL;
-                weight = cpus_weight(span);
                 for_each_domain(cpu, tmp) {
-                        if (weight <= cpus_weight(tmp->span))
+                        if (weight <= cpumask_weight(sched_domain_span(tmp)))
                                 break;
                         if (tmp->flags & flag)
                                 sd = tmp;
@@ -2218,7 +2215,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
                 cpu = task_cpu(p);
 
                 for_each_domain(this_cpu, sd) {
-                        if (cpu_isset(cpu, sd->span)) {
+                        if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
                                 update_shares(sd);
                                 break;
                         }
@@ -2266,7 +2263,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
         else {
                 struct sched_domain *sd;
                 for_each_domain(this_cpu, sd) {
-                        if (cpu_isset(cpu, sd->span)) {
+                        if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
                                 schedstat_inc(sd, ttwu_wake_remote);
                                 break;
                         }
@@ -3109,10 +3106,11 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
                 unsigned long sum_avg_load_per_task;
                 unsigned long avg_load_per_task;
 
-                local_group = cpu_isset(this_cpu, group->cpumask);
+                local_group = cpumask_test_cpu(this_cpu,
+                                               sched_group_cpus(group));
 
                 if (local_group)
-                        balance_cpu = first_cpu(group->cpumask);
+                        balance_cpu = cpumask_first(sched_group_cpus(group));
 
                 /* Tally up the load of all CPUs in the group */
                 sum_weighted_load = sum_nr_running = avg_load = 0;
@@ -3121,13 +3119,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
                 max_cpu_load = 0;
                 min_cpu_load = ~0UL;
 
-                for_each_cpu(i, &group->cpumask) {
-                        struct rq *rq;
-
-                        if (!cpu_isset(i, *cpus))
-                                continue;
-
-                        rq = cpu_rq(i);
+                for_each_cpu_and(i, sched_group_cpus(group), cpus) {
+                        struct rq *rq = cpu_rq(i);
 
                         if (*sd_idle && rq->nr_running)
                                 *sd_idle = 0;
@@ -3238,8 +3231,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
                  */
                 if ((sum_nr_running < min_nr_running) ||
                     (sum_nr_running == min_nr_running &&
-                     first_cpu(group->cpumask) <
-                     first_cpu(group_min->cpumask))) {
+                     cpumask_first(sched_group_cpus(group)) <
+                     cpumask_first(sched_group_cpus(group_min)))) {
                         group_min = group;
                         min_nr_running = sum_nr_running;
                         min_load_per_task = sum_weighted_load /
@@ -3254,8 +3247,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
                 if (sum_nr_running <= group_capacity - 1) {
                         if (sum_nr_running > leader_nr_running ||
                             (sum_nr_running == leader_nr_running &&
-                             first_cpu(group->cpumask) >
-                              first_cpu(group_leader->cpumask))) {
+                             cpumask_first(sched_group_cpus(group)) >
+                             cpumask_first(sched_group_cpus(group_leader)))) {
                                 group_leader = group;
                                 leader_nr_running = sum_nr_running;
                         }
@@ -3400,7 +3393,7 @@ find_busiest_queue(struct sched_group *group, enum cpu_idle_type idle,
         unsigned long max_load = 0;
         int i;
 
-        for_each_cpu(i, &group->cpumask) {
+        for_each_cpu(i, sched_group_cpus(group)) {
                 unsigned long wl;
 
                 if (!cpu_isset(i, *cpus))
@@ -3746,7 +3739,7 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
         /* Search for an sd spanning us and the target CPU. */
         for_each_domain(target_cpu, sd) {
                 if ((sd->flags & SD_LOAD_BALANCE) &&
-                    cpu_isset(busiest_cpu, sd->span))
+                    cpumask_test_cpu(busiest_cpu, sched_domain_span(sd)))
                                 break;
         }
 
@@ -6618,7 +6611,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
         struct sched_group *group = sd->groups;
         char str[256];
 
-        cpulist_scnprintf(str, sizeof(str), sd->span);
+        cpulist_scnprintf(str, sizeof(str), *sched_domain_span(sd));
         cpus_clear(*groupmask);
 
         printk(KERN_DEBUG "%*s domain %d: ", level, "", level);
@@ -6633,11 +6626,11 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
 
         printk(KERN_CONT "span %s level %s\n", str, sd->name);
 
-        if (!cpu_isset(cpu, sd->span)) {
+        if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) {
                 printk(KERN_ERR "ERROR: domain->span does not contain "
                                 "CPU%d\n", cpu);
         }
-        if (!cpu_isset(cpu, group->cpumask)) {
+        if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) {
                 printk(KERN_ERR "ERROR: domain->groups does not contain"
                                 " CPU%d\n", cpu);
         }
@@ -6657,31 +6650,32 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
                         break;
                 }
 
-                if (!cpus_weight(group->cpumask)) {
+                if (!cpumask_weight(sched_group_cpus(group))) {
                         printk(KERN_CONT "\n");
                         printk(KERN_ERR "ERROR: empty group\n");
                         break;
                 }
 
-                if (cpus_intersects(*groupmask, group->cpumask)) {
+                if (cpumask_intersects(groupmask, sched_group_cpus(group))) {
                         printk(KERN_CONT "\n");
                         printk(KERN_ERR "ERROR: repeated CPUs\n");
                         break;
                 }
 
-                cpus_or(*groupmask, *groupmask, group->cpumask);
+                cpumask_or(groupmask, groupmask, sched_group_cpus(group));
 
-                cpulist_scnprintf(str, sizeof(str), group->cpumask);
+                cpulist_scnprintf(str, sizeof(str), *sched_group_cpus(group));
                 printk(KERN_CONT " %s", str);
 
                 group = group->next;
         } while (group != sd->groups);
         printk(KERN_CONT "\n");
 
-        if (!cpus_equal(sd->span, *groupmask))
+        if (!cpumask_equal(sched_domain_span(sd), groupmask))
                 printk(KERN_ERR "ERROR: groups don't span domain->span\n");
 
-        if (sd->parent && !cpus_subset(*groupmask, sd->parent->span))
+        if (sd->parent &&
+            !cpumask_subset(groupmask, sched_domain_span(sd->parent)))
                 printk(KERN_ERR "ERROR: parent span is not a superset "
                         "of domain->span\n");
         return 0;
@@ -6721,7 +6715,7 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
 
 static int sd_degenerate(struct sched_domain *sd)
 {
-        if (cpus_weight(sd->span) == 1)
+        if (cpumask_weight(sched_domain_span(sd)) == 1)
                 return 1;
 
         /* Following flags need at least 2 groups */
@@ -6752,7 +6746,7 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
         if (sd_degenerate(parent))
                 return 1;
 
-        if (!cpus_equal(sd->span, parent->span))
+        if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent)))
                 return 0;
 
         /* Does parent contain flags not in child? */
@@ -6913,10 +6907,10 @@ init_sched_build_groups(const cpumask_t *span, const cpumask_t *cpu_map,
                 int group = group_fn(i, cpu_map, &sg, tmpmask);
                 int j;
 
-                if (cpu_isset(i, *covered))
+                if (cpumask_test_cpu(i, covered))
                         continue;
 
-                cpus_clear(sg->cpumask);
+                cpumask_clear(sched_group_cpus(sg));
                 sg->__cpu_power = 0;
 
                 for_each_cpu(j, span) {
@@ -6924,7 +6918,7 @@ init_sched_build_groups(const cpumask_t *span, const cpumask_t *cpu_map,
                                 continue;
 
                         cpu_set(j, *covered);
-                        cpu_set(j, sg->cpumask);
+                        cpumask_set_cpu(j, sched_group_cpus(sg));
                 }
                 if (!first)
                         first = sg;
@@ -7119,11 +7113,11 @@ static void init_numa_sched_groups_power(struct sched_group *group_head)
         if (!sg)
                 return;
         do {
-                for_each_cpu(j, &sg->cpumask) {
+                for_each_cpu(j, sched_group_cpus(sg)) {
                         struct sched_domain *sd;
 
                         sd = &per_cpu(phys_domains, j);
-                        if (j != first_cpu(sd->groups->cpumask)) {
+                        if (j != cpumask_first(sched_group_cpus(sd->groups))) {
                                 /*
                                  * Only add "power" once for each
                                  * physical package.
@@ -7200,7 +7194,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
 
         WARN_ON(!sd || !sd->groups);
 
-        if (cpu != first_cpu(sd->groups->cpumask))
+        if (cpu != cpumask_first(sched_group_cpus(sd->groups)))
                 return;
 
         child = sd->child;
@@ -7372,7 +7366,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                         sd = &per_cpu(allnodes_domains, i);
                         SD_INIT(sd, ALLNODES);
                         set_domain_attribute(sd, attr);
-                        sd->span = *cpu_map;
+                        cpumask_copy(sched_domain_span(sd), cpu_map);
                         cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask);
                         p = sd;
                         sd_allnodes = 1;
@@ -7382,18 +7376,19 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                 sd = &per_cpu(node_domains, i);
                 SD_INIT(sd, NODE);
                 set_domain_attribute(sd, attr);
-                sched_domain_node_span(cpu_to_node(i), &sd->span);
+                sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
                 sd->parent = p;
                 if (p)
                         p->child = sd;
-                cpus_and(sd->span, sd->span, *cpu_map);
+                cpumask_and(sched_domain_span(sd),
+                            sched_domain_span(sd), cpu_map);
 #endif
 
                 p = sd;
                 sd = &per_cpu(phys_domains, i);
                 SD_INIT(sd, CPU);
                 set_domain_attribute(sd, attr);
-                sd->span = *nodemask;
+                cpumask_copy(sched_domain_span(sd), nodemask);
                 sd->parent = p;
                 if (p)
                         p->child = sd;
@@ -7404,8 +7399,9 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                 sd = &per_cpu(core_domains, i);
                 SD_INIT(sd, MC);
                 set_domain_attribute(sd, attr);
-                sd->span = cpu_coregroup_map(i);
-                cpus_and(sd->span, sd->span, *cpu_map);
+                *sched_domain_span(sd) = cpu_coregroup_map(i);
+                cpumask_and(sched_domain_span(sd),
+                            sched_domain_span(sd), cpu_map);
                 sd->parent = p;
                 p->child = sd;
                 cpu_to_core_group(i, cpu_map, &sd->groups, tmpmask);
@@ -7416,8 +7412,8 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                 sd = &per_cpu(cpu_domains, i);
                 SD_INIT(sd, SIBLING);
                 set_domain_attribute(sd, attr);
-                sd->span = per_cpu(cpu_sibling_map, i);
-                cpus_and(sd->span, sd->span, *cpu_map);
+                cpumask_and(sched_domain_span(sd),
+                            &per_cpu(cpu_sibling_map, i), cpu_map);
                 sd->parent = p;
                 p->child = sd;
                 cpu_to_cpu_group(i, cpu_map, &sd->groups, tmpmask);
@@ -7503,7 +7499,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                         sd->groups = sg;
                 }
                 sg->__cpu_power = 0;
-                sg->cpumask = *nodemask;
+                cpumask_copy(sched_group_cpus(sg), nodemask);
                 sg->next = sg;
                 cpus_or(*covered, *covered, *nodemask);
                 prev = sg;
@@ -7530,7 +7526,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
                                 goto error;
                         }
                         sg->__cpu_power = 0;
-                        sg->cpumask = *tmpmask;
+                        cpumask_copy(sched_group_cpus(sg), tmpmask);
                         sg->next = prev->next;
                         cpus_or(*covered, *covered, *tmpmask);
                         prev->next = sg;
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 98345e45b05..bba00402ed9 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1024,7 +1024,6 @@ static void yield_task_fair(struct rq *rq)
 #if defined(ARCH_HAS_SCHED_WAKE_IDLE)
 static int wake_idle(int cpu, struct task_struct *p)
 {
-        cpumask_t tmp;
         struct sched_domain *sd;
         int i;
 
@@ -1044,10 +1043,9 @@ static int wake_idle(int cpu, struct task_struct *p)
                 if ((sd->flags & SD_WAKE_IDLE)
                     || ((sd->flags & SD_WAKE_IDLE_FAR)
                         && !task_hot(p, task_rq(p)->clock, sd))) {
-                        cpus_and(tmp, sd->span, p->cpus_allowed);
-                        cpus_and(tmp, tmp, cpu_active_map);
-                        for_each_cpu_mask_nr(i, tmp) {
-                                if (idle_cpu(i)) {
+                        for_each_cpu_and(i, sched_domain_span(sd),
+                                         &p->cpus_allowed) {
+                                if (cpu_active(i) && idle_cpu(i)) {
                                         if (i != task_cpu(p)) {
                                                 schedstat_inc(p,
                                                        se.nr_wakeups_idle);
@@ -1240,7 +1238,7 @@ static int select_task_rq_fair(struct task_struct *p, int sync)
          * this_cpu and prev_cpu are present in:
          */
         for_each_domain(this_cpu, sd) {
-                if (cpu_isset(prev_cpu, sd->span)) {
+                if (cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) {
                         this_sd = sd;
                         break;
                 }
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 2bdd4442359..4cd813abc23 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1017,7 +1017,8 @@ static int find_lowest_rq(struct task_struct *task)
                         cpumask_t domain_mask;
                         int       best_cpu;
 
-                        cpus_and(domain_mask, sd->span, *lowest_mask);
+                        cpumask_and(&domain_mask, sched_domain_span(sd),
+                                    lowest_mask);
 
                         best_cpu = pick_optimal_cpu(this_cpu,
                                                     &domain_mask);
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index 7dbf72a2b02..ce340835d05 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -42,7 +42,8 @@ static int show_schedstat(struct seq_file *seq, void *v)
                 for_each_domain(cpu, sd) {
                         enum cpu_idle_type itype;
 
-                        cpumask_scnprintf(mask_str, mask_len, sd->span);
+                        cpumask_scnprintf(mask_str, mask_len,
+                                          *sched_domain_span(sd));
                         seq_printf(seq, "domain%d %s", dcount++, mask_str);
                         for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
                                         itype++) {