Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-devel

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-devel: (62 commits)
  sched: build fix
  sched: better rt-group documentation
  sched: features fix
  sched: /debug/sched_features
  sched: add SCHED_FEAT_DEADLINE
  sched: debug: show a weight tree
  sched: fair: weight calculations
  sched: fair-group: de-couple load-balancing from the rb-trees
  sched: fair-group scheduling vs latency
  sched: rt-group: optimize dequeue_rt_stack
  sched: debug: add some debug code to handle the full hierarchy
  sched: fair-group: SMP-nice for group scheduling
  sched, cpuset: customize sched domains, core
  sched, cpuset: customize sched domains, docs
  sched: prepatory code movement
  sched: rt: multi level group constraints
  sched: task_group hierarchy
  sched: fix the task_group hierarchy for UID grouping
  sched: allow the group scheduler to have multiple levels
  sched: mix tasks and groups
  ...

15 files changed, 144 insertions, 78 deletions

diff --git a/include/asm-alpha/topology.h b/include/asm-alpha/topology.h
index 420ccde6b916..149532e162c4 100644
--- a/include/asm-alpha/topology.h
+++ b/include/asm-alpha/topology.h
@@ -41,8 +41,7 @@ static inline cpumask_t node_to_cpumask(int node)
 
 #define pcibus_to_cpumask(bus)  (cpu_online_map)
 
-#else /* CONFIG_NUMA */
-# include <asm-generic/topology.h>
 #endif /* !CONFIG_NUMA */
+# include <asm-generic/topology.h>
 
 #endif /* _ASM_ALPHA_TOPOLOGY_H */
diff --git a/include/asm-frv/topology.h b/include/asm-frv/topology.h
index abe7298742ac..942724352705 100644
--- a/include/asm-frv/topology.h
+++ b/include/asm-frv/topology.h
@@ -5,10 +5,8 @@
 
 #error NUMA not supported yet
 
-#else /* !CONFIG_NUMA */
+#endif /* CONFIG_NUMA */
 
 #include <asm-generic/topology.h>
 
-#endif /* CONFIG_NUMA */
-
 #endif /* _ASM_TOPOLOGY_H */
diff --git a/include/asm-generic/topology.h b/include/asm-generic/topology.h
index 342a2a0105c4..a6aea79bca4f 100644
--- a/include/asm-generic/topology.h
+++ b/include/asm-generic/topology.h
@@ -27,6 +27,8 @@
 #ifndef _ASM_GENERIC_TOPOLOGY_H
 #define _ASM_GENERIC_TOPOLOGY_H
 
+#ifndef CONFIG_NUMA
+
 /* Other architectures wishing to use this simple topology API should fill
    in the below functions as appropriate in their own <asm/topology.h> file. */
 #ifndef cpu_to_node
@@ -52,4 +54,16 @@
                                 )
 #endif
 
+#endif  /* CONFIG_NUMA */
+
+/* returns pointer to cpumask for specified node */
+#ifndef node_to_cpumask_ptr
+
+#define node_to_cpumask_ptr(v, node)                                    \
+                cpumask_t _##v = node_to_cpumask(node), *v = &_##v
+
+#define node_to_cpumask_ptr_next(v, node)                               \
+                          _##v = node_to_cpumask(node)
+#endif
+
 #endif /* _ASM_GENERIC_TOPOLOGY_H */
diff --git a/include/asm-ia64/topology.h b/include/asm-ia64/topology.h
index 2d67b72b18d0..f2f72ef2a897 100644
--- a/include/asm-ia64/topology.h
+++ b/include/asm-ia64/topology.h
@@ -93,7 +93,7 @@ void build_cpu_to_node_map(void);
         .cache_nice_tries       = 2,                    \
         .busy_idx               = 3,                    \
         .idle_idx               = 2,                    \
-        .newidle_idx            = 0, /* unused */       \
+        .newidle_idx            = 2,                    \
         .wake_idx               = 1,                    \
         .forkexec_idx           = 1,                    \
         .flags                  = SD_LOAD_BALANCE       \
@@ -116,6 +116,11 @@ void build_cpu_to_node_map(void);
 #define smt_capable()                           (smp_num_siblings > 1)
 #endif
 
+#define pcibus_to_cpumask(bus)  (pcibus_to_node(bus) == -1 ? \
+                                        CPU_MASK_ALL : \
+                                        node_to_cpumask(pcibus_to_node(bus)) \
+                                )
+
 #include <asm-generic/topology.h>
 
 #endif /* _ASM_IA64_TOPOLOGY_H */
diff --git a/include/asm-powerpc/topology.h b/include/asm-powerpc/topology.h
index ca23b681ad05..100c6fbfc587 100644
--- a/include/asm-powerpc/topology.h
+++ b/include/asm-powerpc/topology.h
@@ -96,11 +96,10 @@ static inline void sysfs_remove_device_from_node(struct sys_device *dev,
 {
 }
 
+#endif /* CONFIG_NUMA */
 
 #include <asm-generic/topology.h>
 
-#endif /* CONFIG_NUMA */
-
 #ifdef CONFIG_SMP
 #include <asm/cputable.h>
 #define smt_capable()           (cpu_has_feature(CPU_FTR_SMT))
diff --git a/include/asm-sh/topology.h b/include/asm-sh/topology.h
index f402a3b1cfa4..34cdb28e8f44 100644
--- a/include/asm-sh/topology.h
+++ b/include/asm-sh/topology.h
@@ -16,7 +16,7 @@
         .cache_nice_tries       = 2,                    \
         .busy_idx               = 3,                    \
         .idle_idx               = 2,                    \
-        .newidle_idx            = 0,                    \
+        .newidle_idx            = 2,                    \
         .wake_idx               = 1,                    \
         .forkexec_idx           = 1,                    \
         .flags                  = SD_LOAD_BALANCE       \
diff --git a/include/asm-x86/topology.h b/include/asm-x86/topology.h
index 81a29eb08ac4..22073268b481 100644
--- a/include/asm-x86/topology.h
+++ b/include/asm-x86/topology.h
@@ -88,6 +88,17 @@ static inline int cpu_to_node(int cpu)
 #endif
         return per_cpu(x86_cpu_to_node_map, cpu);
 }
+
+#ifdef  CONFIG_NUMA
+
+/* Returns a pointer to the cpumask of CPUs on Node 'node'. */
+#define node_to_cpumask_ptr(v, node)            \
+                cpumask_t *v = &(node_to_cpumask_map[node])
+
+#define node_to_cpumask_ptr_next(v, node)       \
+                           v = &(node_to_cpumask_map[node])
+#endif
+
 #endif /* CONFIG_X86_64 */
 
 /*
@@ -136,17 +147,13 @@ extern unsigned long node_remap_size[];
 
 # define SD_CACHE_NICE_TRIES    2
 # define SD_IDLE_IDX            2
-# define SD_NEWIDLE_IDX         0
+# define SD_NEWIDLE_IDX         2
 # define SD_FORKEXEC_IDX        1
 
 #endif
 
 /* sched_domains SD_NODE_INIT for NUMAQ machines */
 #define SD_NODE_INIT (struct sched_domain) {            \
-        .span                   = CPU_MASK_NONE,        \
-        .parent                 = NULL,                 \
-        .child                  = NULL,                 \
-        .groups                 = NULL,                 \
         .min_interval           = 8,                    \
         .max_interval           = 32,                   \
         .busy_factor            = 32,                   \
@@ -164,7 +171,6 @@ extern unsigned long node_remap_size[];
                                 | SD_WAKE_BALANCE,      \
         .last_balance           = jiffies,              \
         .balance_interval       = 1,                    \
-        .nr_balance_failed      = 0,                    \
 }
 
 #ifdef CONFIG_X86_64_ACPI_NUMA
@@ -174,10 +180,10 @@ extern int __node_distance(int, int);
 
 #else /* CONFIG_NUMA */
 
-#include <asm-generic/topology.h>
-
 #endif
 
+#include <asm-generic/topology.h>
+
 extern cpumask_t cpu_coregroup_map(int cpu);
 
 #ifdef ENABLE_TOPO_DEFINES
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index acad1105d942..1dbe074f1c64 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -108,6 +108,7 @@ extern int __bitmap_weight(const unsigned long *bitmap, int bits);
 
 extern int bitmap_scnprintf(char *buf, unsigned int len,
                         const unsigned long *src, int nbits);
+extern int bitmap_scnprintf_len(unsigned int len);
 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
                         unsigned long *dst, int nbits);
 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index 7047f58306a7..259c8051155d 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -222,8 +222,13 @@ int __next_cpu(int n, const cpumask_t *srcp);
 #define next_cpu(n, src)        ({ (void)(src); 1; })
 #endif
 
+#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
+extern cpumask_t *cpumask_of_cpu_map;
+#define cpumask_of_cpu(cpu)    (cpumask_of_cpu_map[cpu])
+
+#else
 #define cpumask_of_cpu(cpu)                                             \
-({                                                                      \
+(*({                                                                    \
         typeof(_unused_cpumask_arg_) m;                                 \
         if (sizeof(m) == sizeof(unsigned long)) {                       \
                 m.bits[0] = 1UL<<(cpu);                                 \
@@ -231,8 +236,9 @@ int __next_cpu(int n, const cpumask_t *srcp);
                 cpus_clear(m);                                          \
                 cpu_set((cpu), m);                                      \
         }                                                               \
-        m;                                                              \
-})
+        &m;                                                             \
+}))
+#endif
 
 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
 
@@ -243,6 +249,8 @@ int __next_cpu(int n, const cpumask_t *srcp);
         [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD                 \
 } }
 
+#define CPU_MASK_ALL_PTR        (&CPU_MASK_ALL)
+
 #else
 
 #define CPU_MASK_ALL                                                    \
@@ -251,6 +259,10 @@ int __next_cpu(int n, const cpumask_t *srcp);
         [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD                 \
 } }
 
+/* cpu_mask_all is in init/main.c */
+extern cpumask_t cpu_mask_all;
+#define CPU_MASK_ALL_PTR        (&cpu_mask_all)
+
 #endif
 
 #define CPU_MASK_NONE                                                   \
@@ -273,6 +285,13 @@ static inline int __cpumask_scnprintf(char *buf, int len,
         return bitmap_scnprintf(buf, len, srcp->bits, nbits);
 }
 
+#define cpumask_scnprintf_len(len) \
+                        __cpumask_scnprintf_len((len))
+static inline int __cpumask_scnprintf_len(int len)
+{
+        return bitmap_scnprintf_len(len);
+}
+
 #define cpumask_parse_user(ubuf, ulen, dst) \
                         __cpumask_parse_user((ubuf), (ulen), &(dst), NR_CPUS)
 static inline int __cpumask_parse_user(const char __user *buf, int len,
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 0a26be353cb3..726761e24003 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -20,8 +20,8 @@ extern int number_of_cpusets;	/* How many cpusets are defined in system? */
 extern int cpuset_init_early(void);
 extern int cpuset_init(void);
 extern void cpuset_init_smp(void);
-extern cpumask_t cpuset_cpus_allowed(struct task_struct *p);
-extern cpumask_t cpuset_cpus_allowed_locked(struct task_struct *p);
+extern void cpuset_cpus_allowed(struct task_struct *p, cpumask_t *mask);
+extern void cpuset_cpus_allowed_locked(struct task_struct *p, cpumask_t *mask);
 extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
 #define cpuset_current_mems_allowed (current->mems_allowed)
 void cpuset_init_current_mems_allowed(void);
@@ -84,13 +84,14 @@ static inline int cpuset_init_early(void) { return 0; }
 static inline int cpuset_init(void) { return 0; }
 static inline void cpuset_init_smp(void) {}
 
-static inline cpumask_t cpuset_cpus_allowed(struct task_struct *p)
+static inline void cpuset_cpus_allowed(struct task_struct *p, cpumask_t *mask)
 {
-        return cpu_possible_map;
+        *mask = cpu_possible_map;
 }
-static inline cpumask_t cpuset_cpus_allowed_locked(struct task_struct *p)
+static inline void cpuset_cpus_allowed_locked(struct task_struct *p,
+                                                                cpumask_t *mask)
 {
-        return cpu_possible_map;
+        *mask = cpu_possible_map;
 }
 
 static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 1f74e1d7415f..37a6f5bc4a92 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -151,6 +151,9 @@ extern struct group_info init_groups;
         .cpus_allowed   = CPU_MASK_ALL,                                 \
         .mm             = NULL,                                         \
         .active_mm      = &init_mm,                                     \
+        .se             = {                                             \
+                .group_node     = LIST_HEAD_INIT(tsk.se.group_node),    \
+        },                                                              \
         .rt             = {                                             \
                 .run_list       = LIST_HEAD_INIT(tsk.rt.run_list),      \
                 .time_slice     = HZ,                                   \
diff --git a/include/linux/ktime.h b/include/linux/ktime.h
index 2cd7fa73d1af..ce5983225be4 100644
--- a/include/linux/ktime.h
+++ b/include/linux/ktime.h
@@ -327,4 +327,10 @@ extern void ktime_get_ts(struct timespec *ts);
 /* Get the real (wall-) time in timespec format: */
 #define ktime_get_real_ts(ts)   getnstimeofday(ts)
 
+static inline ktime_t ns_to_ktime(u64 ns)
+{
+        static const ktime_t ktime_zero = { .tv64 = 0 };
+        return ktime_add_ns(ktime_zero, ns);
+}
+
 #endif
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6a1e7afb099b..be6914014c70 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -704,6 +704,7 @@ enum cpu_idle_type {
 #define SD_POWERSAVINGS_BALANCE 256     /* Balance for power savings */
 #define SD_SHARE_PKG_RESOURCES  512     /* Domain members share cpu pkg resources */
 #define SD_SERIALIZE            1024    /* Only a single load balancing instance */
+#define SD_WAKE_IDLE_FAR        2048    /* Gain latency sacrificing cache hit */
 
 #define BALANCE_FOR_MC_POWER    \
         (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
@@ -733,12 +734,31 @@ struct sched_group {
         u32 reciprocal_cpu_power;
 };
 
+enum sched_domain_level {
+        SD_LV_NONE = 0,
+        SD_LV_SIBLING,
+        SD_LV_MC,
+        SD_LV_CPU,
+        SD_LV_NODE,
+        SD_LV_ALLNODES,
+        SD_LV_MAX
+};
+
+struct sched_domain_attr {
+        int relax_domain_level;
+};
+
+#define SD_ATTR_INIT    (struct sched_domain_attr) {    \
+        .relax_domain_level = -1,                       \
+}
+
 struct sched_domain {
         /* These fields must be setup */
         struct sched_domain *parent;    /* top domain must be null terminated */
         struct sched_domain *child;     /* bottom domain must be null terminated */
         struct sched_group *groups;     /* the balancing groups of the domain */
         cpumask_t span;                 /* span of all CPUs in this domain */
+        int first_cpu;                  /* cache of the first cpu in this domain */
         unsigned long min_interval;     /* Minimum balance interval ms */
         unsigned long max_interval;     /* Maximum balance interval ms */
         unsigned int busy_factor;       /* less balancing by factor if busy */
@@ -750,6 +770,7 @@ struct sched_domain {
         unsigned int wake_idx;
         unsigned int forkexec_idx;
         int flags;                      /* See SD_* */
+        enum sched_domain_level level;
 
         /* Runtime fields. */
         unsigned long last_balance;     /* init to jiffies. units in jiffies */
@@ -789,7 +810,8 @@ struct sched_domain {
 #endif
 };
 
-extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new);
+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);
 
 #endif  /* CONFIG_SMP */
@@ -889,7 +911,8 @@ struct sched_class {
         void (*set_curr_task) (struct rq *rq);
         void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
         void (*task_new) (struct rq *rq, struct task_struct *p);
-        void (*set_cpus_allowed)(struct task_struct *p, cpumask_t *newmask);
+        void (*set_cpus_allowed)(struct task_struct *p,
+                                 const cpumask_t *newmask);
 
         void (*join_domain)(struct rq *rq);
         void (*leave_domain)(struct rq *rq);
@@ -923,6 +946,7 @@ struct load_weight {
 struct sched_entity {
         struct load_weight      load;           /* for load-balancing */
         struct rb_node          run_node;
+        struct list_head        group_node;
         unsigned int            on_rq;
 
         u64                     exec_start;
@@ -982,6 +1006,7 @@ struct sched_rt_entity {
         unsigned long timeout;
         int nr_cpus_allowed;
 
+        struct sched_rt_entity *back;
 #ifdef CONFIG_RT_GROUP_SCHED
         struct sched_rt_entity  *parent;
         /* rq on which this entity is (to be) queued: */
@@ -1502,15 +1527,21 @@ static inline void put_task_struct(struct task_struct *t)
 #define used_math() tsk_used_math(current)
 
 #ifdef CONFIG_SMP
-extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
+extern int set_cpus_allowed_ptr(struct task_struct *p,
+                                const cpumask_t *new_mask);
 #else
-static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
+static inline int set_cpus_allowed_ptr(struct task_struct *p,
+                                       const cpumask_t *new_mask)
 {
-        if (!cpu_isset(0, new_mask))
+        if (!cpu_isset(0, *new_mask))
                 return -EINVAL;
         return 0;
 }
 #endif
+static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
+{
+        return set_cpus_allowed_ptr(p, &new_mask);
+}
 
 extern unsigned long long sched_clock(void);
 
@@ -1551,7 +1582,6 @@ static inline void wake_up_idle_cpu(int cpu) { }
 extern unsigned int sysctl_sched_latency;
 extern unsigned int sysctl_sched_min_granularity;
 extern unsigned int sysctl_sched_wakeup_granularity;
-extern unsigned int sysctl_sched_batch_wakeup_granularity;
 extern unsigned int sysctl_sched_child_runs_first;
 extern unsigned int sysctl_sched_features;
 extern unsigned int sysctl_sched_migration_cost;
@@ -1564,6 +1594,10 @@ int sched_nr_latency_handler(struct ctl_table *table, int write,
 extern unsigned int sysctl_sched_rt_period;
 extern int sysctl_sched_rt_runtime;
 
+int sched_rt_handler(struct ctl_table *table, int write,
+                struct file *filp, void __user *buffer, size_t *lenp,
+                loff_t *ppos);
+
 extern unsigned int sysctl_sched_compat_yield;
 
 #ifdef CONFIG_RT_MUTEXES
@@ -2031,7 +2065,7 @@ static inline void arch_pick_mmap_layout(struct mm_struct *mm)
 }
 #endif
 
-extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
+extern long sched_setaffinity(pid_t pid, const cpumask_t *new_mask);
 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
 
 extern int sched_mc_power_savings, sched_smt_power_savings;
@@ -2041,8 +2075,11 @@ extern void normalize_rt_tasks(void);
 #ifdef CONFIG_GROUP_SCHED
 
 extern struct task_group init_task_group;
+#ifdef CONFIG_USER_SCHED
+extern struct task_group root_task_group;
+#endif
 
-extern struct task_group *sched_create_group(void);
+extern struct task_group *sched_create_group(struct task_group *parent);
 extern void sched_destroy_group(struct task_group *tg);
 extern void sched_move_task(struct task_struct *tsk);
 #ifdef CONFIG_FAIR_GROUP_SCHED
@@ -2053,6 +2090,9 @@ extern unsigned long sched_group_shares(struct task_group *tg);
 extern int sched_group_set_rt_runtime(struct task_group *tg,
                                       long rt_runtime_us);
 extern long sched_group_rt_runtime(struct task_group *tg);
+extern int sched_group_set_rt_period(struct task_group *tg,
+                                      long rt_period_us);
+extern long sched_group_rt_period(struct task_group *tg);
 #endif
 #endif
 
diff --git a/include/linux/sysdev.h b/include/linux/sysdev.h
index f752e73bf977..f2767bc6b735 100644
--- a/include/linux/sysdev.h
+++ b/include/linux/sysdev.h
@@ -45,12 +45,16 @@ struct sysdev_class_attribute {
         ssize_t (*store)(struct sysdev_class *, const char *, size_t);
 };
 
-#define SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)             \
-struct sysdev_class_attribute attr_##_name = {                  \
+#define _SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)            \
+{                                                               \
         .attr = {.name = __stringify(_name), .mode = _mode },   \
         .show   = _show,                                        \
         .store  = _store,                                       \
-};
+}
+
+#define SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)             \
+        struct sysdev_class_attribute attr_##_name =            \
+                _SYSDEV_CLASS_ATTR(_name,_mode,_show,_store)
 
 
 extern int sysdev_class_register(struct sysdev_class *);
@@ -100,15 +104,16 @@ struct sysdev_attribute {
 };
 
 
-#define _SYSDEV_ATTR(_name,_mode,_show,_store)                  \
+#define _SYSDEV_ATTR(_name, _mode, _show, _store)               \
 {                                                               \
         .attr = { .name = __stringify(_name), .mode = _mode },  \
         .show   = _show,                                        \
         .store  = _store,                                       \
 }
 
-#define SYSDEV_ATTR(_name,_mode,_show,_store)           \
-struct sysdev_attribute attr_##_name = _SYSDEV_ATTR(_name,_mode,_show,_store);
+#define SYSDEV_ATTR(_name, _mode, _show, _store)                \
+        struct sysdev_attribute attr_##_name =                  \
+                _SYSDEV_ATTR(_name, _mode, _show, _store);
 
 extern int sysdev_create_file(struct sys_device *, struct sysdev_attribute *);
 extern void sysdev_remove_file(struct sys_device *, struct sysdev_attribute *);
diff --git a/include/linux/topology.h b/include/linux/topology.h
index bd14f8b30f09..4bb7074a2c3a 100644
--- a/include/linux/topology.h
+++ b/include/linux/topology.h
@@ -38,16 +38,15 @@
 #endif
 
 #ifndef nr_cpus_node
-#define nr_cpus_node(node)                                                      \
-        ({                                                                      \
-                cpumask_t __tmp__;                                              \
-                __tmp__ = node_to_cpumask(node);                                \
-                cpus_weight(__tmp__);                                           \
+#define nr_cpus_node(node)                              \
+        ({                                              \
+                node_to_cpumask_ptr(__tmp__, node);     \
+                cpus_weight(*__tmp__);                  \
         })
 #endif
 
-#define for_each_node_with_cpus(node)                                           \
-        for_each_online_node(node)                                              \
+#define for_each_node_with_cpus(node)                   \
+        for_each_online_node(node)                      \
                 if (nr_cpus_node(node))
 
 void arch_update_cpu_topology(void);
@@ -80,7 +79,9 @@ void arch_update_cpu_topology(void);
  * by defining their own arch-specific initializer in include/asm/topology.h.
  * A definition there will automagically override these default initializers
  * and allow arch-specific performance tuning of sched_domains.
+ * (Only non-zero and non-null fields need be specified.)
  */
+
 #ifdef CONFIG_SCHED_SMT
 /* MCD - Do we really need this?  It is always on if CONFIG_SCHED_SMT is,
  * so can't we drop this in favor of CONFIG_SCHED_SMT?
@@ -89,20 +90,10 @@ void arch_update_cpu_topology(void);
 /* Common values for SMT siblings */
 #ifndef SD_SIBLING_INIT
 #define SD_SIBLING_INIT (struct sched_domain) {         \
-        .span                   = CPU_MASK_NONE,        \
-        .parent                 = NULL,                 \
-        .child                  = NULL,                 \
-        .groups                 = NULL,                 \
         .min_interval           = 1,                    \
         .max_interval           = 2,                    \
         .busy_factor            = 64,                   \
         .imbalance_pct          = 110,                  \
-        .cache_nice_tries       = 0,                    \
-        .busy_idx               = 0,                    \
-        .idle_idx               = 0,                    \
-        .newidle_idx            = 0,                    \
-        .wake_idx               = 0,                    \
-        .forkexec_idx           = 0,                    \
         .flags                  = SD_LOAD_BALANCE       \
                                 | SD_BALANCE_NEWIDLE    \
                                 | SD_BALANCE_FORK       \
@@ -112,7 +103,6 @@ void arch_update_cpu_topology(void);
                                 | SD_SHARE_CPUPOWER,    \
         .last_balance           = jiffies,              \
         .balance_interval       = 1,                    \
-        .nr_balance_failed      = 0,                    \
 }
 #endif
 #endif /* CONFIG_SCHED_SMT */
@@ -121,18 +111,12 @@ void arch_update_cpu_topology(void);
 /* Common values for MC siblings. for now mostly derived from SD_CPU_INIT */
 #ifndef SD_MC_INIT
 #define SD_MC_INIT (struct sched_domain) {              \
-        .span                   = CPU_MASK_NONE,        \
-        .parent                 = NULL,                 \
-        .child                  = NULL,                 \
-        .groups                 = NULL,                 \
         .min_interval           = 1,                    \
         .max_interval           = 4,                    \
         .busy_factor            = 64,                   \
         .imbalance_pct          = 125,                  \
         .cache_nice_tries       = 1,                    \
         .busy_idx               = 2,                    \
-        .idle_idx               = 0,                    \
-        .newidle_idx            = 0,                    \
         .wake_idx               = 1,                    \
         .forkexec_idx           = 1,                    \
         .flags                  = SD_LOAD_BALANCE       \
@@ -144,7 +128,6 @@ void arch_update_cpu_topology(void);
                                 | BALANCE_FOR_MC_POWER, \
         .last_balance           = jiffies,              \
         .balance_interval       = 1,                    \
-        .nr_balance_failed      = 0,                    \
 }
 #endif
 #endif /* CONFIG_SCHED_MC */
@@ -152,10 +135,6 @@ void arch_update_cpu_topology(void);
 /* Common values for CPUs */
 #ifndef SD_CPU_INIT
 #define SD_CPU_INIT (struct sched_domain) {             \
-        .span                   = CPU_MASK_NONE,        \
-        .parent                 = NULL,                 \
-        .child                  = NULL,                 \
-        .groups                 = NULL,                 \
         .min_interval           = 1,                    \
         .max_interval           = 4,                    \
         .busy_factor            = 64,                   \
@@ -174,16 +153,11 @@ void arch_update_cpu_topology(void);
                                 | BALANCE_FOR_PKG_POWER,\
         .last_balance           = jiffies,              \
         .balance_interval       = 1,                    \
-        .nr_balance_failed      = 0,                    \
 }
 #endif
 
 /* sched_domains SD_ALLNODES_INIT for NUMA machines */
 #define SD_ALLNODES_INIT (struct sched_domain) {        \
-        .span                   = CPU_MASK_NONE,        \
-        .parent                 = NULL,                 \
-        .child                  = NULL,                 \
-        .groups                 = NULL,                 \
         .min_interval           = 64,                   \
         .max_interval           = 64*num_online_cpus(), \
         .busy_factor            = 128,                  \
@@ -191,14 +165,10 @@ void arch_update_cpu_topology(void);
         .cache_nice_tries       = 1,                    \
         .busy_idx               = 3,                    \
         .idle_idx               = 3,                    \
-        .newidle_idx            = 0, /* unused */       \
-        .wake_idx               = 0, /* unused */       \
-        .forkexec_idx           = 0, /* unused */       \
         .flags                  = SD_LOAD_BALANCE       \
                                 | SD_SERIALIZE, \
         .last_balance           = jiffies,              \
         .balance_interval       = 64,                   \
-        .nr_balance_failed      = 0,                    \
 }
 
 #ifdef CONFIG_NUMA