cpufreq: schedutil: Avoid reducing frequency of busy CPUs prematurely
[linux-2.6/btrfs-unstable.git] / include / linux / tick.h
blobfe01e68bf520c792f8c06989dd3e811baf8e98b5
1 /*
2 * Tick related global functions
3 */
4 #ifndef _LINUX_TICK_H
5 #define _LINUX_TICK_H
7 #include <linux/clockchips.h>
8 #include <linux/irqflags.h>
9 #include <linux/percpu.h>
10 #include <linux/context_tracking_state.h>
11 #include <linux/cpumask.h>
12 #include <linux/sched.h>
14 #ifdef CONFIG_GENERIC_CLOCKEVENTS
15 extern void __init tick_init(void);
16 /* Should be core only, but ARM BL switcher requires it */
17 extern void tick_suspend_local(void);
18 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
19 extern void tick_resume_local(void);
20 extern void tick_handover_do_timer(void);
21 extern void tick_cleanup_dead_cpu(int cpu);
22 #else /* CONFIG_GENERIC_CLOCKEVENTS */
23 static inline void tick_init(void) { }
24 static inline void tick_suspend_local(void) { }
25 static inline void tick_resume_local(void) { }
26 static inline void tick_handover_do_timer(void) { }
27 static inline void tick_cleanup_dead_cpu(int cpu) { }
28 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
30 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
31 extern void tick_freeze(void);
32 extern void tick_unfreeze(void);
33 #else
34 static inline void tick_freeze(void) { }
35 static inline void tick_unfreeze(void) { }
36 #endif
38 #ifdef CONFIG_TICK_ONESHOT
39 extern void tick_irq_enter(void);
40 # ifndef arch_needs_cpu
41 # define arch_needs_cpu() (0)
42 # endif
43 # else
44 static inline void tick_irq_enter(void) { }
45 #endif
47 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
48 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
49 #else
50 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
51 #endif
53 enum tick_broadcast_mode {
54 TICK_BROADCAST_OFF,
55 TICK_BROADCAST_ON,
56 TICK_BROADCAST_FORCE,
59 enum tick_broadcast_state {
60 TICK_BROADCAST_EXIT,
61 TICK_BROADCAST_ENTER,
64 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
65 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
66 #else
67 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
68 #endif /* BROADCAST */
70 #ifdef CONFIG_GENERIC_CLOCKEVENTS
71 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
72 #else
73 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
75 return 0;
77 #endif
79 static inline void tick_broadcast_enable(void)
81 tick_broadcast_control(TICK_BROADCAST_ON);
83 static inline void tick_broadcast_disable(void)
85 tick_broadcast_control(TICK_BROADCAST_OFF);
87 static inline void tick_broadcast_force(void)
89 tick_broadcast_control(TICK_BROADCAST_FORCE);
91 static inline int tick_broadcast_enter(void)
93 return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
95 static inline void tick_broadcast_exit(void)
97 tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
100 enum tick_dep_bits {
101 TICK_DEP_BIT_POSIX_TIMER = 0,
102 TICK_DEP_BIT_PERF_EVENTS = 1,
103 TICK_DEP_BIT_SCHED = 2,
104 TICK_DEP_BIT_CLOCK_UNSTABLE = 3
107 #define TICK_DEP_MASK_NONE 0
108 #define TICK_DEP_MASK_POSIX_TIMER (1 << TICK_DEP_BIT_POSIX_TIMER)
109 #define TICK_DEP_MASK_PERF_EVENTS (1 << TICK_DEP_BIT_PERF_EVENTS)
110 #define TICK_DEP_MASK_SCHED (1 << TICK_DEP_BIT_SCHED)
111 #define TICK_DEP_MASK_CLOCK_UNSTABLE (1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
113 #ifdef CONFIG_NO_HZ_COMMON
114 extern bool tick_nohz_enabled;
115 extern int tick_nohz_tick_stopped(void);
116 extern void tick_nohz_idle_enter(void);
117 extern void tick_nohz_idle_exit(void);
118 extern void tick_nohz_irq_exit(void);
119 extern ktime_t tick_nohz_get_sleep_length(void);
120 extern unsigned long tick_nohz_get_idle_calls(void);
121 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
122 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
123 #else /* !CONFIG_NO_HZ_COMMON */
124 #define tick_nohz_enabled (0)
125 static inline int tick_nohz_tick_stopped(void) { return 0; }
126 static inline void tick_nohz_idle_enter(void) { }
127 static inline void tick_nohz_idle_exit(void) { }
129 static inline ktime_t tick_nohz_get_sleep_length(void)
131 return NSEC_PER_SEC / HZ;
133 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
134 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
135 #endif /* !CONFIG_NO_HZ_COMMON */
137 #ifdef CONFIG_NO_HZ_FULL
138 extern bool tick_nohz_full_running;
139 extern cpumask_var_t tick_nohz_full_mask;
140 extern cpumask_var_t housekeeping_mask;
142 static inline bool tick_nohz_full_enabled(void)
144 if (!context_tracking_is_enabled())
145 return false;
147 return tick_nohz_full_running;
150 static inline bool tick_nohz_full_cpu(int cpu)
152 if (!tick_nohz_full_enabled())
153 return false;
155 return cpumask_test_cpu(cpu, tick_nohz_full_mask);
158 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
160 if (tick_nohz_full_enabled())
161 cpumask_or(mask, mask, tick_nohz_full_mask);
164 static inline int housekeeping_any_cpu(void)
166 return cpumask_any_and(housekeeping_mask, cpu_online_mask);
169 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
170 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
171 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
172 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
173 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
174 enum tick_dep_bits bit);
175 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
176 enum tick_dep_bits bit);
177 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
178 enum tick_dep_bits bit);
179 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
180 enum tick_dep_bits bit);
183 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
184 * on top of static keys.
186 static inline void tick_dep_set(enum tick_dep_bits bit)
188 if (tick_nohz_full_enabled())
189 tick_nohz_dep_set(bit);
192 static inline void tick_dep_clear(enum tick_dep_bits bit)
194 if (tick_nohz_full_enabled())
195 tick_nohz_dep_clear(bit);
198 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
200 if (tick_nohz_full_cpu(cpu))
201 tick_nohz_dep_set_cpu(cpu, bit);
204 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
206 if (tick_nohz_full_cpu(cpu))
207 tick_nohz_dep_clear_cpu(cpu, bit);
210 static inline void tick_dep_set_task(struct task_struct *tsk,
211 enum tick_dep_bits bit)
213 if (tick_nohz_full_enabled())
214 tick_nohz_dep_set_task(tsk, bit);
216 static inline void tick_dep_clear_task(struct task_struct *tsk,
217 enum tick_dep_bits bit)
219 if (tick_nohz_full_enabled())
220 tick_nohz_dep_clear_task(tsk, bit);
222 static inline void tick_dep_set_signal(struct signal_struct *signal,
223 enum tick_dep_bits bit)
225 if (tick_nohz_full_enabled())
226 tick_nohz_dep_set_signal(signal, bit);
228 static inline void tick_dep_clear_signal(struct signal_struct *signal,
229 enum tick_dep_bits bit)
231 if (tick_nohz_full_enabled())
232 tick_nohz_dep_clear_signal(signal, bit);
235 extern void tick_nohz_full_kick_cpu(int cpu);
236 extern void __tick_nohz_task_switch(void);
237 #else
238 static inline int housekeeping_any_cpu(void)
240 return smp_processor_id();
242 static inline bool tick_nohz_full_enabled(void) { return false; }
243 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
244 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
246 static inline void tick_dep_set(enum tick_dep_bits bit) { }
247 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
248 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
249 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
250 static inline void tick_dep_set_task(struct task_struct *tsk,
251 enum tick_dep_bits bit) { }
252 static inline void tick_dep_clear_task(struct task_struct *tsk,
253 enum tick_dep_bits bit) { }
254 static inline void tick_dep_set_signal(struct signal_struct *signal,
255 enum tick_dep_bits bit) { }
256 static inline void tick_dep_clear_signal(struct signal_struct *signal,
257 enum tick_dep_bits bit) { }
259 static inline void tick_nohz_full_kick_cpu(int cpu) { }
260 static inline void __tick_nohz_task_switch(void) { }
261 #endif
263 static inline const struct cpumask *housekeeping_cpumask(void)
265 #ifdef CONFIG_NO_HZ_FULL
266 if (tick_nohz_full_enabled())
267 return housekeeping_mask;
268 #endif
269 return cpu_possible_mask;
272 static inline bool is_housekeeping_cpu(int cpu)
274 #ifdef CONFIG_NO_HZ_FULL
275 if (tick_nohz_full_enabled())
276 return cpumask_test_cpu(cpu, housekeeping_mask);
277 #endif
278 return true;
281 static inline void housekeeping_affine(struct task_struct *t)
283 #ifdef CONFIG_NO_HZ_FULL
284 if (tick_nohz_full_enabled())
285 set_cpus_allowed_ptr(t, housekeeping_mask);
287 #endif
290 static inline void tick_nohz_task_switch(void)
292 if (tick_nohz_full_enabled())
293 __tick_nohz_task_switch();
296 #endif