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  /* Groups have different max 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 /*
  31  * Increase resolution of cpu_capacity calculations
  32  */
  33 #define SCHED_CAPACITY_SHIFT    SCHED_FIXEDPOINT_SHIFT
  34 #define SCHED_CAPACITY_SCALE    (1L << SCHED_CAPACITY_SHIFT)
  35
  36 #ifdef CONFIG_SCHED_SMT
  37 static inline int cpu_smt_flags(void)
  38 {
  39         return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
  40 }
  41 #endif
  42
  43 #ifdef CONFIG_SCHED_MC
  44 static inline int cpu_core_flags(void)
  45 {
  46         return SD_SHARE_PKG_RESOURCES;
  47 }
  48 #endif
  49
  50 #ifdef CONFIG_NUMA
  51 static inline int cpu_numa_flags(void)
  52 {
  53         return SD_NUMA;
  54 }
  55 #endif
  56
  57 extern int arch_asym_cpu_priority(int cpu);
  58
  59 struct sched_domain_attr {
  60         int relax_domain_level;
  61 };
  62
  63 #define SD_ATTR_INIT    (struct sched_domain_attr) {    \
  64         .relax_domain_level = -1,                       \
  65 }
  66
  67 extern int sched_domain_level_max;
  68
  69 struct sched_group;
  70
  71 struct sched_domain_shared {
  72         atomic_t        ref;
  73         atomic_t        nr_busy_cpus;
  74         int             has_idle_cores;
  75 };
  76
  77 struct sched_domain {
  78         /* These fields must be setup */
  79         struct sched_domain *parent;    /* top domain must be null terminated */
  80         struct sched_domain *child;     /* bottom domain must be null terminated */
  81         struct sched_group *groups;     /* the balancing groups of the domain */
  82         unsigned long min_interval;     /* Minimum balance interval ms */
  83         unsigned long max_interval;     /* Maximum balance interval ms */
  84         unsigned int busy_factor;       /* less balancing by factor if busy */
  85         unsigned int imbalance_pct;     /* No balance until over watermark */
  86         unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
  87         unsigned int busy_idx;
  88         unsigned int idle_idx;
  89         unsigned int newidle_idx;
  90         unsigned int wake_idx;
  91         unsigned int forkexec_idx;
  92         unsigned int smt_gain;
  93
  94         int nohz_idle;                  /* NOHZ IDLE status */
  95         int flags;                      /* See SD_* */
  96         int level;
  97
  98         /* Runtime fields. */
  99         unsigned long last_balance;     /* init to jiffies. units in jiffies */
 100         unsigned int balance_interval;  /* initialise to 1. units in ms. */
 101         unsigned int nr_balance_failed; /* initialise to 0 */
 102
 103         /* idle_balance() stats */
 104         u64 max_newidle_lb_cost;
 105         unsigned long next_decay_max_lb_cost;
 106
 107         u64 avg_scan_cost;              /* select_idle_sibling */
 108
 109 #ifdef CONFIG_SCHEDSTATS
 110         /* load_balance() stats */
 111         unsigned int lb_count[CPU_MAX_IDLE_TYPES];
 112         unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
 113         unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
 114         unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
 115         unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
 116         unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
 117         unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
 118         unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
 119
 120         /* Active load balancing */
 121         unsigned int alb_count;
 122         unsigned int alb_failed;
 123         unsigned int alb_pushed;
 124
 125         /* SD_BALANCE_EXEC stats */
 126         unsigned int sbe_count;
 127         unsigned int sbe_balanced;
 128         unsigned int sbe_pushed;
 129
 130         /* SD_BALANCE_FORK stats */
 131         unsigned int sbf_count;
 132         unsigned int sbf_balanced;
 133         unsigned int sbf_pushed;
 134
 135         /* try_to_wake_up() stats */
 136         unsigned int ttwu_wake_remote;
 137         unsigned int ttwu_move_affine;
 138         unsigned int ttwu_move_balance;
 139 #endif
 140 #ifdef CONFIG_SCHED_DEBUG
 141         char *name;
 142 #endif
 143         union {
 144                 void *private;          /* used during construction */
 145                 struct rcu_head rcu;    /* used during destruction */
 146         };
 147         struct sched_domain_shared *shared;
 148
 149         unsigned int span_weight;
 150         /*
 151          * Span of all CPUs in this domain.
 152          *
 153          * NOTE: this field is variable length. (Allocated dynamically
 154          * by attaching extra space to the end of the structure,
 155          * depending on how many CPUs the kernel has booted up with)
 156          */
 157         unsigned long span[0];
 158 };
 159
 160 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
 161 {
 162         return to_cpumask(sd->span);
 163 }
 164
 165 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
 166                                     struct sched_domain_attr *dattr_new);
 167
 168 /* Allocate an array of sched domains, for partition_sched_domains(). */
 169 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
 170 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
 171
 172 bool cpus_share_cache(int this_cpu, int that_cpu);
 173
 174 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
 175 typedef int (*sched_domain_flags_f)(void);
 176
 177 #define SDTL_OVERLAP    0x01
 178
 179 struct sd_data {
 180         struct sched_domain **__percpu sd;
 181         struct sched_domain_shared **__percpu sds;
 182         struct sched_group **__percpu sg;
 183         struct sched_group_capacity **__percpu sgc;
 184 };
 185
 186 struct sched_domain_topology_level {
 187         sched_domain_mask_f mask;
 188         sched_domain_flags_f sd_flags;
 189         int                 flags;
 190         int                 numa_level;
 191         struct sd_data      data;
 192 #ifdef CONFIG_SCHED_DEBUG
 193         char                *name;
 194 #endif
 195 };
 196
 197 extern void set_sched_topology(struct sched_domain_topology_level *tl);
 198
 199 #ifdef CONFIG_SCHED_DEBUG
 200 # define SD_INIT_NAME(type)             .name = #type
 201 #else
 202 # define SD_INIT_NAME(type)
 203 #endif
 204
 205 #else /* CONFIG_SMP */
 206
 207 struct sched_domain_attr;
 208
 209 static inline void
 210 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
 211                         struct sched_domain_attr *dattr_new)
 212 {
 213 }
 214
 215 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
 216 {
 217         return true;
 218 }
 219
 220 #endif  /* !CONFIG_SMP */
 221
 222 static inline int task_node(const struct task_struct *p)
 223 {
 224         return cpu_to_node(task_cpu(p));
 225 }
 226
 227 #endif /* _LINUX_SCHED_TOPOLOGY_H */