xref: /openbmc/linux/include/linux/sched/topology.h (revision a701d28e)
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 /* Generate SD flag indexes */
15 #define SD_FLAG(name, mflags) __##name,
16 enum {
17 	#include <linux/sched/sd_flags.h>
18 	__SD_FLAG_CNT,
19 };
20 #undef SD_FLAG
21 /* Generate SD flag bits */
22 #define SD_FLAG(name, mflags) name = 1 << __##name,
23 enum {
24 	#include <linux/sched/sd_flags.h>
25 };
26 #undef SD_FLAG
27 
28 #ifdef CONFIG_SCHED_DEBUG
29 
30 struct sd_flag_debug {
31 	unsigned int meta_flags;
32 	char *name;
33 };
34 extern const struct sd_flag_debug sd_flag_debug[];
35 
36 #endif
37 
38 #ifdef CONFIG_SCHED_SMT
39 static inline int cpu_smt_flags(void)
40 {
41 	return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
42 }
43 #endif
44 
45 #ifdef CONFIG_SCHED_MC
46 static inline int cpu_core_flags(void)
47 {
48 	return SD_SHARE_PKG_RESOURCES;
49 }
50 #endif
51 
52 #ifdef CONFIG_NUMA
53 static inline int cpu_numa_flags(void)
54 {
55 	return SD_NUMA;
56 }
57 #endif
58 
59 extern int arch_asym_cpu_priority(int cpu);
60 
61 struct sched_domain_attr {
62 	int relax_domain_level;
63 };
64 
65 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
66 	.relax_domain_level = -1,			\
67 }
68 
69 extern int sched_domain_level_max;
70 
71 struct sched_group;
72 
73 struct sched_domain_shared {
74 	atomic_t	ref;
75 	atomic_t	nr_busy_cpus;
76 	int		has_idle_cores;
77 };
78 
79 struct sched_domain {
80 	/* These fields must be setup */
81 	struct sched_domain __rcu *parent;	/* top domain must be null terminated */
82 	struct sched_domain __rcu *child;	/* bottom domain must be null terminated */
83 	struct sched_group *groups;	/* the balancing groups of the domain */
84 	unsigned long min_interval;	/* Minimum balance interval ms */
85 	unsigned long max_interval;	/* Maximum balance interval ms */
86 	unsigned int busy_factor;	/* less balancing by factor if busy */
87 	unsigned int imbalance_pct;	/* No balance until over watermark */
88 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
89 
90 	int nohz_idle;			/* NOHZ IDLE status */
91 	int flags;			/* See SD_* */
92 	int level;
93 
94 	/* Runtime fields. */
95 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
96 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
97 	unsigned int nr_balance_failed; /* initialise to 0 */
98 
99 	/* idle_balance() stats */
100 	u64 max_newidle_lb_cost;
101 	unsigned long next_decay_max_lb_cost;
102 
103 	u64 avg_scan_cost;		/* select_idle_sibling */
104 
105 #ifdef CONFIG_SCHEDSTATS
106 	/* load_balance() stats */
107 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
108 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
109 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
110 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
111 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
112 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
113 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
114 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
115 
116 	/* Active load balancing */
117 	unsigned int alb_count;
118 	unsigned int alb_failed;
119 	unsigned int alb_pushed;
120 
121 	/* SD_BALANCE_EXEC stats */
122 	unsigned int sbe_count;
123 	unsigned int sbe_balanced;
124 	unsigned int sbe_pushed;
125 
126 	/* SD_BALANCE_FORK stats */
127 	unsigned int sbf_count;
128 	unsigned int sbf_balanced;
129 	unsigned int sbf_pushed;
130 
131 	/* try_to_wake_up() stats */
132 	unsigned int ttwu_wake_remote;
133 	unsigned int ttwu_move_affine;
134 	unsigned int ttwu_move_balance;
135 #endif
136 #ifdef CONFIG_SCHED_DEBUG
137 	char *name;
138 #endif
139 	union {
140 		void *private;		/* used during construction */
141 		struct rcu_head rcu;	/* used during destruction */
142 	};
143 	struct sched_domain_shared *shared;
144 
145 	unsigned int span_weight;
146 	/*
147 	 * Span of all CPUs in this domain.
148 	 *
149 	 * NOTE: this field is variable length. (Allocated dynamically
150 	 * by attaching extra space to the end of the structure,
151 	 * depending on how many CPUs the kernel has booted up with)
152 	 */
153 	unsigned long span[];
154 };
155 
156 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
157 {
158 	return to_cpumask(sd->span);
159 }
160 
161 extern void partition_sched_domains_locked(int ndoms_new,
162 					   cpumask_var_t doms_new[],
163 					   struct sched_domain_attr *dattr_new);
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_locked(int ndoms_new, cpumask_var_t doms_new[],
211 			       struct sched_domain_attr *dattr_new)
212 {
213 }
214 
215 static inline void
216 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
217 			struct sched_domain_attr *dattr_new)
218 {
219 }
220 
221 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
222 {
223 	return true;
224 }
225 
226 #endif	/* !CONFIG_SMP */
227 
228 #ifndef arch_scale_cpu_capacity
229 /**
230  * arch_scale_cpu_capacity - get the capacity scale factor of a given CPU.
231  * @cpu: the CPU in question.
232  *
233  * Return: the CPU scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
234  *
235  *             max_perf(cpu)
236  *      ----------------------------- * SCHED_CAPACITY_SCALE
237  *      max(max_perf(c) : c \in CPUs)
238  */
239 static __always_inline
240 unsigned long arch_scale_cpu_capacity(int cpu)
241 {
242 	return SCHED_CAPACITY_SCALE;
243 }
244 #endif
245 
246 #ifndef arch_scale_thermal_pressure
247 static __always_inline
248 unsigned long arch_scale_thermal_pressure(int cpu)
249 {
250 	return 0;
251 }
252 #endif
253 
254 #ifndef arch_set_thermal_pressure
255 static __always_inline
256 void arch_set_thermal_pressure(const struct cpumask *cpus,
257 			       unsigned long th_pressure)
258 { }
259 #endif
260 
261 static inline int task_node(const struct task_struct *p)
262 {
263 	return cpu_to_node(task_cpu(p));
264 }
265 
266 #endif /* _LINUX_SCHED_TOPOLOGY_H */
267