projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blame
| Commit | Line | Data |
|---|---|---|
| a1a04ec3 TG |
1 | /* |
| 2 | * Generic entry point for the idle threads | |
| 3 | */ | |
| 4 | #include <linux/sched.h> | |
| 5 | #include <linux/cpu.h> | |
| d1669912 TG |
6 | #include <linux/tick.h> |
| 7 | #include <linux/mm.h> | |
| a1a04ec3 | 8 | |
| d1669912 TG |
9 | #include <asm/tlb.h> |
| 10 | ||
| 11 | #include <trace/events/power.h> | |
| 12 | ||
| d1669912 TG |
13 | static int __read_mostly cpu_idle_force_poll; |
| 14 | ||
| 15 | void cpu_idle_poll_ctrl(bool enable) | |
| 16 | { | |
| 17 | if (enable) { | |
| 18 | cpu_idle_force_poll++; | |
| 19 | } else { | |
| 20 | cpu_idle_force_poll--; | |
| 21 | WARN_ON_ONCE(cpu_idle_force_poll < 0); | |
| 22 | } | |
| 23 | } | |
| 24 | ||
| 25 | #ifdef CONFIG_GENERIC_IDLE_POLL_SETUP | |
| 26 | static int __init cpu_idle_poll_setup(char *__unused) | |
| 27 | { | |
| 28 | cpu_idle_force_poll = 1; | |
| 29 | return 1; | |
| 30 | } | |
| 31 | __setup("nohlt", cpu_idle_poll_setup); | |
| 32 | ||
| 33 | static int __init cpu_idle_nopoll_setup(char *__unused) | |
| 34 | { | |
| 35 | cpu_idle_force_poll = 0; | |
| 36 | return 1; | |
| 37 | } | |
| 38 | __setup("hlt", cpu_idle_nopoll_setup); | |
| 39 | #endif | |
| 40 | ||
| 41 | static inline int cpu_idle_poll(void) | |
| 42 | { | |
| 43 | trace_cpu_idle_rcuidle(0, smp_processor_id()); | |
| 44 | local_irq_enable(); | |
| 45 | while (!need_resched()) | |
| 46 | cpu_relax(); | |
| 47 | trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); | |
| 48 | return 1; | |
| 49 | } | |
| 50 | ||
| 51 | /* Weak implementations for optional arch specific functions */ | |
| 52 | void __weak arch_cpu_idle_prepare(void) { } | |
| 53 | void __weak arch_cpu_idle_enter(void) { } | |
| 54 | void __weak arch_cpu_idle_exit(void) { } | |
| 55 | void __weak arch_cpu_idle_dead(void) { } | |
| 56 | void __weak arch_cpu_idle(void) | |
| 57 | { | |
| 58 | cpu_idle_force_poll = 1; | |
| 59 | } | |
| 60 | ||
| 61 | /* | |
| 62 | * Generic idle loop implementation | |
| 63 | */ | |
| 64 | static void cpu_idle_loop(void) | |
| 65 | { | |
| 66 | while (1) { | |
| 67 | tick_nohz_idle_enter(); | |
| 68 | ||
| 69 | while (!need_resched()) { | |
| 70 | check_pgt_cache(); | |
| 71 | rmb(); | |
| 72 | ||
| 73 | if (cpu_is_offline(smp_processor_id())) | |
| 74 | arch_cpu_idle_dead(); | |
| 75 | ||
| 76 | local_irq_disable(); | |
| 77 | arch_cpu_idle_enter(); | |
| 78 | ||
| ab86e974 LT |
79 | /* |
| 80 | * In poll mode we reenable interrupts and spin. | |
| 81 | * | |
| 82 | * Also if we detected in the wakeup from idle | |
| 83 | * path that the tick broadcast device expired | |
| 84 | * for us, we don't want to go deep idle as we | |
| 85 | * know that the IPI is going to arrive right | |
| 86 | * away | |
| 87 | */ | |
| 88 | if (cpu_idle_force_poll || tick_check_broadcast_expired()) { | |
| d1669912 TG |
89 | cpu_idle_poll(); |
| 90 | } else { | |
| 91 | current_clr_polling(); | |
| 92 | if (!need_resched()) { | |
| 93 | stop_critical_timings(); | |
| 94 | rcu_idle_enter(); | |
| 95 | arch_cpu_idle(); | |
| 96 | WARN_ON_ONCE(irqs_disabled()); | |
| 97 | rcu_idle_exit(); | |
| 98 | start_critical_timings(); | |
| 99 | } else { | |
| 100 | local_irq_enable(); | |
| 101 | } | |
| 102 | current_set_polling(); | |
| 103 | } | |
| 104 | arch_cpu_idle_exit(); | |
| 105 | } | |
| 106 | tick_nohz_idle_exit(); | |
| 107 | schedule_preempt_disabled(); | |
| 108 | } | |
| 109 | } | |
| 110 | ||
| 111 | void cpu_startup_entry(enum cpuhp_state state) | |
| 112 | { | |
| 113 | current_set_polling(); | |
| 114 | arch_cpu_idle_prepare(); | |
| 115 | cpu_idle_loop(); | |
| 116 | } |