forked from luck/tmp_suning_uos_patched
145 lines
3.3 KiB
C
145 lines
3.3 KiB
C
|
/*
|
||
|
* Generic entry point for the idle threads
|
||
|
*/
|
||
|
#include <linux/sched.h>
|
||
|
#include <linux/cpu.h>
|
||
|
#include <linux/cpuidle.h>
|
||
|
#include <linux/tick.h>
|
||
|
#include <linux/mm.h>
|
||
|
#include <linux/stackprotector.h>
|
||
|
|
||
|
#include <asm/tlb.h>
|
||
|
|
||
|
#include <trace/events/power.h>
|
||
|
|
||
|
static int __read_mostly cpu_idle_force_poll;
|
||
|
|
||
|
void cpu_idle_poll_ctrl(bool enable)
|
||
|
{
|
||
|
if (enable) {
|
||
|
cpu_idle_force_poll++;
|
||
|
} else {
|
||
|
cpu_idle_force_poll--;
|
||
|
WARN_ON_ONCE(cpu_idle_force_poll < 0);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_GENERIC_IDLE_POLL_SETUP
|
||
|
static int __init cpu_idle_poll_setup(char *__unused)
|
||
|
{
|
||
|
cpu_idle_force_poll = 1;
|
||
|
return 1;
|
||
|
}
|
||
|
__setup("nohlt", cpu_idle_poll_setup);
|
||
|
|
||
|
static int __init cpu_idle_nopoll_setup(char *__unused)
|
||
|
{
|
||
|
cpu_idle_force_poll = 0;
|
||
|
return 1;
|
||
|
}
|
||
|
__setup("hlt", cpu_idle_nopoll_setup);
|
||
|
#endif
|
||
|
|
||
|
static inline int cpu_idle_poll(void)
|
||
|
{
|
||
|
rcu_idle_enter();
|
||
|
trace_cpu_idle_rcuidle(0, smp_processor_id());
|
||
|
local_irq_enable();
|
||
|
while (!tif_need_resched())
|
||
|
cpu_relax();
|
||
|
trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
|
||
|
rcu_idle_exit();
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
/* Weak implementations for optional arch specific functions */
|
||
|
void __weak arch_cpu_idle_prepare(void) { }
|
||
|
void __weak arch_cpu_idle_enter(void) { }
|
||
|
void __weak arch_cpu_idle_exit(void) { }
|
||
|
void __weak arch_cpu_idle_dead(void) { }
|
||
|
void __weak arch_cpu_idle(void)
|
||
|
{
|
||
|
cpu_idle_force_poll = 1;
|
||
|
local_irq_enable();
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Generic idle loop implementation
|
||
|
*/
|
||
|
static void cpu_idle_loop(void)
|
||
|
{
|
||
|
while (1) {
|
||
|
tick_nohz_idle_enter();
|
||
|
|
||
|
while (!need_resched()) {
|
||
|
check_pgt_cache();
|
||
|
rmb();
|
||
|
|
||
|
if (cpu_is_offline(smp_processor_id()))
|
||
|
arch_cpu_idle_dead();
|
||
|
|
||
|
local_irq_disable();
|
||
|
arch_cpu_idle_enter();
|
||
|
|
||
|
/*
|
||
|
* In poll mode we reenable interrupts and spin.
|
||
|
*
|
||
|
* Also if we detected in the wakeup from idle
|
||
|
* path that the tick broadcast device expired
|
||
|
* for us, we don't want to go deep idle as we
|
||
|
* know that the IPI is going to arrive right
|
||
|
* away
|
||
|
*/
|
||
|
if (cpu_idle_force_poll || tick_check_broadcast_expired()) {
|
||
|
cpu_idle_poll();
|
||
|
} else {
|
||
|
if (!current_clr_polling_and_test()) {
|
||
|
stop_critical_timings();
|
||
|
rcu_idle_enter();
|
||
|
if (cpuidle_idle_call())
|
||
|
arch_cpu_idle();
|
||
|
if (WARN_ON_ONCE(irqs_disabled()))
|
||
|
local_irq_enable();
|
||
|
rcu_idle_exit();
|
||
|
start_critical_timings();
|
||
|
} else {
|
||
|
local_irq_enable();
|
||
|
}
|
||
|
__current_set_polling();
|
||
|
}
|
||
|
arch_cpu_idle_exit();
|
||
|
/*
|
||
|
* We need to test and propagate the TIF_NEED_RESCHED
|
||
|
* bit here because we might not have send the
|
||
|
* reschedule IPI to idle tasks.
|
||
|
*/
|
||
|
if (tif_need_resched())
|
||
|
set_preempt_need_resched();
|
||
|
}
|
||
|
tick_nohz_idle_exit();
|
||
|
schedule_preempt_disabled();
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void cpu_startup_entry(enum cpuhp_state state)
|
||
|
{
|
||
|
/*
|
||
|
* This #ifdef needs to die, but it's too late in the cycle to
|
||
|
* make this generic (arm and sh have never invoked the canary
|
||
|
* init for the non boot cpus!). Will be fixed in 3.11
|
||
|
*/
|
||
|
#ifdef CONFIG_X86
|
||
|
/*
|
||
|
* If we're the non-boot CPU, nothing set the stack canary up
|
||
|
* for us. The boot CPU already has it initialized but no harm
|
||
|
* in doing it again. This is a good place for updating it, as
|
||
|
* we wont ever return from this function (so the invalid
|
||
|
* canaries already on the stack wont ever trigger).
|
||
|
*/
|
||
|
boot_init_stack_canary();
|
||
|
#endif
|
||
|
__current_set_polling();
|
||
|
arch_cpu_idle_prepare();
|
||
|
cpu_idle_loop();
|
||
|
}
|