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-rw-r--r--kernel/cpu/idle.c147
-rw-r--r--kernel/sched/idle.c17
2 files changed, 10 insertions, 154 deletions
diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c
deleted file mode 100644
index b7976a127178..000000000000
--- a/kernel/cpu/idle.c
+++ /dev/null
@@ -1,147 +0,0 @@
1/*
2 * Generic entry point for the idle threads
3 */
4#include <linux/sched.h>
5#include <linux/cpu.h>
6#include <linux/cpuidle.h>
7#include <linux/tick.h>
8#include <linux/mm.h>
9#include <linux/stackprotector.h>
10
11#include <asm/tlb.h>
12
13#include <trace/events/power.h>
14
15static int __read_mostly cpu_idle_force_poll;
16
17void cpu_idle_poll_ctrl(bool enable)
18{
19 if (enable) {
20 cpu_idle_force_poll++;
21 } else {
22 cpu_idle_force_poll--;
23 WARN_ON_ONCE(cpu_idle_force_poll < 0);
24 }
25}
26
27#ifdef CONFIG_GENERIC_IDLE_POLL_SETUP
28static int __init cpu_idle_poll_setup(char *__unused)
29{
30 cpu_idle_force_poll = 1;
31 return 1;
32}
33__setup("nohlt", cpu_idle_poll_setup);
34
35static int __init cpu_idle_nopoll_setup(char *__unused)
36{
37 cpu_idle_force_poll = 0;
38 return 1;
39}
40__setup("hlt", cpu_idle_nopoll_setup);
41#endif
42
43static inline int cpu_idle_poll(void)
44{
45 rcu_idle_enter();
46 trace_cpu_idle_rcuidle(0, smp_processor_id());
47 local_irq_enable();
48 while (!tif_need_resched())
49 cpu_relax();
50 trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
51 rcu_idle_exit();
52 return 1;
53}
54
55/* Weak implementations for optional arch specific functions */
56void __weak arch_cpu_idle_prepare(void) { }
57void __weak arch_cpu_idle_enter(void) { }
58void __weak arch_cpu_idle_exit(void) { }
59void __weak arch_cpu_idle_dead(void) { }
60void __weak arch_cpu_idle(void)
61{
62 cpu_idle_force_poll = 1;
63 local_irq_enable();
64}
65
66/*
67 * Generic idle loop implementation
68 */
69static void cpu_idle_loop(void)
70{
71 while (1) {
72 tick_nohz_idle_enter();
73
74 while (!need_resched()) {
75 check_pgt_cache();
76 rmb();
77
78 if (cpu_is_offline(smp_processor_id()))
79 arch_cpu_idle_dead();
80
81 local_irq_disable();
82 arch_cpu_idle_enter();
83
84 /*
85 * In poll mode we reenable interrupts and spin.
86 *
87 * Also if we detected in the wakeup from idle
88 * path that the tick broadcast device expired
89 * for us, we don't want to go deep idle as we
90 * know that the IPI is going to arrive right
91 * away
92 */
93 if (cpu_idle_force_poll || tick_check_broadcast_expired()) {
94 cpu_idle_poll();
95 } else {
96 if (!current_clr_polling_and_test()) {
97 stop_critical_timings();
98 rcu_idle_enter();
99 if (cpuidle_idle_call())
100 arch_cpu_idle();
101 if (WARN_ON_ONCE(irqs_disabled()))
102 local_irq_enable();
103 rcu_idle_exit();
104 start_critical_timings();
105 } else {
106 local_irq_enable();
107 }
108 __current_set_polling();
109 }
110 arch_cpu_idle_exit();
111 }
112
113 /*
114 * Since we fell out of the loop above, we know
115 * TIF_NEED_RESCHED must be set, propagate it into
116 * PREEMPT_NEED_RESCHED.
117 *
118 * This is required because for polling idle loops we will
119 * not have had an IPI to fold the state for us.
120 */
121 preempt_set_need_resched();
122 tick_nohz_idle_exit();
123 schedule_preempt_disabled();
124 }
125}
126
127void cpu_startup_entry(enum cpuhp_state state)
128{
129 /*
130 * This #ifdef needs to die, but it's too late in the cycle to
131 * make this generic (arm and sh have never invoked the canary
132 * init for the non boot cpus!). Will be fixed in 3.11
133 */
134#ifdef CONFIG_X86
135 /*
136 * If we're the non-boot CPU, nothing set the stack canary up
137 * for us. The boot CPU already has it initialized but no harm
138 * in doing it again. This is a good place for updating it, as
139 * we wont ever return from this function (so the invalid
140 * canaries already on the stack wont ever trigger).
141 */
142 boot_init_stack_canary();
143#endif
144 __current_set_polling();
145 arch_cpu_idle_prepare();
146 cpu_idle_loop();
147}
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 14ca43430aee..b7976a127178 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -108,14 +108,17 @@ static void cpu_idle_loop(void)
108 __current_set_polling(); 108 __current_set_polling();
109 } 109 }
110 arch_cpu_idle_exit(); 110 arch_cpu_idle_exit();
111 /*
112 * We need to test and propagate the TIF_NEED_RESCHED
113 * bit here because we might not have send the
114 * reschedule IPI to idle tasks.
115 */
116 if (tif_need_resched())
117 set_preempt_need_resched();
118 } 111 }
112
113 /*
114 * Since we fell out of the loop above, we know
115 * TIF_NEED_RESCHED must be set, propagate it into
116 * PREEMPT_NEED_RESCHED.
117 *
118 * This is required because for polling idle loops we will
119 * not have had an IPI to fold the state for us.
120 */
121 preempt_set_need_resched();
119 tick_nohz_idle_exit(); 122 tick_nohz_idle_exit();
120 schedule_preempt_disabled(); 123 schedule_preempt_disabled();
121 } 124 }
generated by cgit v1.2.2 (git 2.25.0) at 2025-02-25 04:03:39 -0500