include/linux/sched/topology.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_SCHED_TOPOLOGY_H
   3 #define _LINUX_SCHED_TOPOLOGY_H
   4
   5 #include <linux/topology.h>
   6
   7 #include <linux/sched/idle.h>
   8
   9 /*
  10  * sched-domains (multiprocessor balancing) declarations:
  11  */
  12 #ifdef CONFIG_SMP
  13
  14 #define SD_LOAD_BALANCE         0x0001  /* Do load balancing on this domain. */
  15 #define SD_BALANCE_NEWIDLE      0x0002  /* Balance when about to become idle */
  16 #define SD_BALANCE_EXEC         0x0004  /* Balance on exec */
  17 #define SD_BALANCE_FORK         0x0008  /* Balance on fork, clone */
  18 #define SD_BALANCE_WAKE         0x0010  /* Balance on wakeup */
  19 #define SD_WAKE_AFFINE          0x0020  /* Wake task to waking CPU */
  20 #define SD_ASYM_CPUCAPACITY     0x0040  /* Domain members have different CPU capacities */
  21 #define SD_SHARE_CPUCAPACITY    0x0080  /* Domain members share CPU capacity */
  22 #define SD_SHARE_POWERDOMAIN    0x0100  /* Domain members share power domain */
  23 #define SD_SHARE_PKG_RESOURCES  0x0200  /* Domain members share CPU pkg resources */
  24 #define SD_SERIALIZE            0x0400  /* Only a single load balancing instance */
  25 #define SD_ASYM_PACKING         0x0800  /* Place busy groups earlier in the domain */
  26 #define SD_PREFER_SIBLING       0x1000  /* Prefer to place tasks in a sibling domain */
  27 #define SD_OVERLAP              0x2000  /* sched_domains of this level overlap */
  28 #define SD_NUMA                 0x4000  /* cross-node balancing */
  29
  30 #ifdef CONFIG_SCHED_SMT
  31 static inline int cpu_smt_flags(void)
  32 {
  33         return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
  34 }
  35 #endif
  36
  37 #ifdef CONFIG_SCHED_MC
  38 static inline int cpu_core_flags(void)
  39 {
  40         return SD_SHARE_PKG_RESOURCES;
  41 }
  42 #endif
  43
  44 #ifdef CONFIG_NUMA
  45 static inline int cpu_numa_flags(void)
  46 {
  47         return SD_NUMA;
  48 }
  49 #endif
  50
  51 extern int arch_asym_cpu_priority(int cpu);
  52
  53 struct sched_domain_attr {
  54         int relax_domain_level;
  55 };
  56
  57 #define SD_ATTR_INIT    (struct sched_domain_attr) {    \
  58         .relax_domain_level = -1,                       \
  59 }
  60
  61 extern int sched_domain_level_max;
  62
  63 struct sched_group;
  64
  65 struct sched_domain_shared {
  66         atomic_t        ref;
  67         atomic_t        nr_busy_cpus;
  68         int             has_idle_cores;
  69 };
  70
  71 struct sched_domain {
  72         /* These fields must be setup */
  73         struct sched_domain __rcu *parent;      /* top domain must be null terminated */
  74         struct sched_domain __rcu *child;       /* bottom domain must be null terminated */
  75         struct sched_group *groups;     /* the balancing groups of the domain */
  76         unsigned long min_interval;     /* Minimum balance interval ms */
  77         unsigned long max_interval;     /* Maximum balance interval ms */
  78         unsigned int busy_factor;       /* less balancing by factor if busy */
  79         unsigned int imbalance_pct;     /* No balance until over watermark */
  80         unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
  81
  82         int nohz_idle;                  /* NOHZ IDLE status */
  83         int flags;                      /* See SD_* */
  84         int level;
  85
  86         /* Runtime fields. */
  87         unsigned long last_balance;     /* init to jiffies. units in jiffies */
  88         unsigned int balance_interval;  /* initialise to 1. units in ms. */
  89         unsigned int nr_balance_failed; /* initialise to 0 */
  90
  91         /* idle_balance() stats */
  92         u64 max_newidle_lb_cost;
  93         unsigned long next_decay_max_lb_cost;
  94
  95         u64 avg_scan_cost;              /* select_idle_sibling */
  96
  97 #ifdef CONFIG_SCHEDSTATS
  98         /* load_balance() stats */
  99         unsigned int lb_count[CPU_MAX_IDLE_TYPES];
 100         unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
 101         unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
 102         unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
 103         unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
 104         unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
 105         unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
 106         unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
 107
 108         /* Active load balancing */
 109         unsigned int alb_count;
 110         unsigned int alb_failed;
 111         unsigned int alb_pushed;
 112
 113         /* SD_BALANCE_EXEC stats */
 114         unsigned int sbe_count;
 115         unsigned int sbe_balanced;
 116         unsigned int sbe_pushed;
 117
 118         /* SD_BALANCE_FORK stats */
 119         unsigned int sbf_count;
 120         unsigned int sbf_balanced;
 121         unsigned int sbf_pushed;
 122
 123         /* try_to_wake_up() stats */
 124         unsigned int ttwu_wake_remote;
 125         unsigned int ttwu_move_affine;
 126         unsigned int ttwu_move_balance;
 127 #endif
 128 #ifdef CONFIG_SCHED_DEBUG
 129         char *name;
 130 #endif
 131         union {
 132                 void *private;          /* used during construction */
 133                 struct rcu_head rcu;    /* used during destruction */
 134         };
 135         struct sched_domain_shared *shared;
 136
 137         unsigned int span_weight;
 138         /*
 139          * Span of all CPUs in this domain.
 140          *
 141          * NOTE: this field is variable length. (Allocated dynamically
 142          * by attaching extra space to the end of the structure,
 143          * depending on how many CPUs the kernel has booted up with)
 144          */
 145         unsigned long span[0];
 146 };
 147
 148 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
 149 {
 150         return to_cpumask(sd->span);
 151 }
 152
 153 extern void partition_sched_domains_locked(int ndoms_new,
 154                                            cpumask_var_t doms_new[],
 155                                            struct sched_domain_attr *dattr_new);
 156
 157 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
 158                                     struct sched_domain_attr *dattr_new);
 159
 160 /* Allocate an array of sched domains, for partition_sched_domains(). */
 161 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
 162 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
 163
 164 bool cpus_share_cache(int this_cpu, int that_cpu);
 165
 166 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
 167 typedef int (*sched_domain_flags_f)(void);
 168
 169 #define SDTL_OVERLAP    0x01
 170
 171 struct sd_data {
 172         struct sched_domain *__percpu *sd;
 173         struct sched_domain_shared *__percpu *sds;
 174         struct sched_group *__percpu *sg;
 175         struct sched_group_capacity *__percpu *sgc;
 176 };
 177
 178 struct sched_domain_topology_level {
 179         sched_domain_mask_f mask;
 180         sched_domain_flags_f sd_flags;
 181         int                 flags;
 182         int                 numa_level;
 183         struct sd_data      data;
 184 #ifdef CONFIG_SCHED_DEBUG
 185         char                *name;
 186 #endif
 187 };
 188
 189 extern void set_sched_topology(struct sched_domain_topology_level *tl);
 190
 191 #ifdef CONFIG_SCHED_DEBUG
 192 # define SD_INIT_NAME(type)             .name = #type
 193 #else
 194 # define SD_INIT_NAME(type)
 195 #endif
 196
 197 #else /* CONFIG_SMP */
 198
 199 struct sched_domain_attr;
 200
 201 static inline void
 202 partition_sched_domains_locked(int ndoms_new, cpumask_var_t doms_new[],
 203                                struct sched_domain_attr *dattr_new)
 204 {
 205 }
 206
 207 static inline void
 208 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
 209                         struct sched_domain_attr *dattr_new)
 210 {
 211 }
 212
 213 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
 214 {
 215         return true;
 216 }
 217
 218 #endif  /* !CONFIG_SMP */
 219
 220 #ifndef arch_scale_cpu_capacity
 221 static __always_inline
 222 unsigned long arch_scale_cpu_capacity(int cpu)
 223 {
 224         return SCHED_CAPACITY_SCALE;
 225 }
 226 #endif
 227
 228 static inline int task_node(const struct task_struct *p)
 229 {
 230         return cpu_to_node(task_cpu(p));
 231 }
 232
 233 #endif /* _LINUX_SCHED_TOPOLOGY_H */