/**
* tick_nohz_idle_exit - restart the idle tick from the idle task
*
* Restart the idle tick when the CPU is woken up from idle
* This also exit the RCU extended quiescent state. The CPU
* can use RCU again after this function is called.
*/
void tick_nohz_idle_exit(void)
{
int cpu = smp_processor_id();
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
unsigned long ticks;
#endif
ktime_t now;
local_irq_disable();
WARN_ON_ONCE(!ts->inidle);
ts->inidle = 0;
if (ts->idle_active || ts->tick_stopped)
now = ktime_get();
if (ts->idle_active)
tick_nohz_stop_idle(cpu, now);
if (!ts->tick_stopped) {
local_irq_enable();
return;
}
/* Update jiffies first */
select_nohz_load_balancer(0);
tick_do_update_jiffies64(now);
#ifdef CONFIG_MTK_SCHED_CMP
update_cpu_load_nohz();
#endif
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
/*
* We stopped the tick in idle. Update process times would miss the
* time we slept as update_process_times does only a 1 tick
* accounting. Enforce that this is accounted to idle !
*/
ticks = jiffies - ts->idle_jiffies;
/*
* We might be one off. Do not randomly account a huge number of ticks!
*/
if (ticks && ticks < LONG_MAX)
account_idle_ticks(ticks);
#endif
calc_load_exit_idle();
touch_softlockup_watchdog();
/*
* Cancel the scheduled timer and restore the tick
*/
ts->tick_stopped = 0;
ts->idle_exittime = now;
tick_nohz_restart(ts, now);
local_irq_enable();
}
void tick_nohz_idle_exit(void)
{
int cpu = smp_processor_id();
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
unsigned long ticks;
#endif
ktime_t now;
local_irq_disable();
WARN_ON_ONCE(!ts->inidle);
ts->inidle = 0;
/* Cancel the timer because CPU already waken up from the C-states*/
menu_hrtimer_cancel();
if (ts->idle_active || ts->tick_stopped)
now = ktime_get();
if (ts->idle_active)
tick_nohz_stop_idle(cpu, now);
if (!ts->tick_stopped) {
local_irq_enable();
return;
}
select_nohz_load_balancer(0);
tick_do_update_jiffies64(now);
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
ticks = jiffies - ts->idle_jiffies;
if (ticks && ticks < LONG_MAX)
account_idle_ticks(ticks);
#endif
calc_load_exit_idle();
touch_softlockup_watchdog();
ts->tick_stopped = 0;
ts->idle_exittime = now;
tick_nohz_restart(ts, now);
local_irq_enable();
}
static void tick_nohz_account_idle_ticks(struct tick_sched *ts)
{
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
unsigned long ticks;
/*
* We stopped the tick in idle. Update process times would miss the
* time we slept as update_process_times does only a 1 tick
* accounting. Enforce that this is accounted to idle !
*/
ticks = jiffies - ts->idle_jiffies;
/*
* We might be one off. Do not randomly account a huge number of ticks!
*/
if (ticks && ticks < LONG_MAX)
account_idle_ticks(ticks);
#endif
}
static void do_stolen_accounting(void)
{
struct vcpu_runstate_info state;
struct vcpu_runstate_info *snap;
s64 blocked, runnable, offline, stolen;
cputime_t ticks;
get_runstate_snapshot(&state);
WARN_ON(state.state != RUNSTATE_running);
snap = &__get_cpu_var(xen_runstate_snapshot);
/* work out how much time the VCPU has not been runn*ing* */
blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked];
runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable];
offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline];
*snap = state;
/* Add the appropriate number of ticks of stolen time,
including any left-overs from last time. */
stolen = runnable + offline + __this_cpu_read(xen_residual_stolen);
if (stolen < 0)
stolen = 0;
ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen);
__this_cpu_write(xen_residual_stolen, stolen);
account_steal_ticks(ticks);
/* Add the appropriate number of ticks of blocked time,
including any left-overs from last time. */
blocked += __this_cpu_read(xen_residual_blocked);
if (blocked < 0)
blocked = 0;
ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked);
__this_cpu_write(xen_residual_blocked, blocked);
account_idle_ticks(ticks);
}
static void do_stolen_accounting(void)
{
struct vcpu_runstate_info state;
struct vcpu_runstate_info *snap;
s64 blocked, runnable, offline, stolen;
cputime_t ticks;
get_runstate_snapshot(&state);
WARN_ON(state.state != RUNSTATE_running);
snap = &__get_cpu_var(xen_runstate_snapshot);
blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked];
runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable];
offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline];
*snap = state;
stolen = runnable + offline + __this_cpu_read(xen_residual_stolen);
if (stolen < 0)
stolen = 0;
ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen);
__this_cpu_write(xen_residual_stolen, stolen);
account_steal_ticks(ticks);
blocked += __this_cpu_read(xen_residual_blocked);
if (blocked < 0)
blocked = 0;
ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked);
__this_cpu_write(xen_residual_blocked, blocked);
account_idle_ticks(ticks);
}
static unsigned long
consider_steal_time(unsigned long new_itm)
{
unsigned long stolen, blocked;
unsigned long delta_itm = 0, stolentick = 0;
int cpu = smp_processor_id();
struct vcpu_runstate_info runstate;
struct task_struct *p = current;
get_runstate_snapshot(&runstate);
/*
* Check for vcpu migration effect
* In this case, itc value is reversed.
* This causes huge stolen value.
* This function just checks and reject this effect.
*/
if (!time_after_eq(runstate.time[RUNSTATE_blocked],
per_cpu(xen_blocked_time, cpu)))
blocked = 0;
if (!time_after_eq(runstate.time[RUNSTATE_runnable] +
runstate.time[RUNSTATE_offline],
per_cpu(xen_stolen_time, cpu)))
stolen = 0;
if (!time_after(delta_itm + new_itm, ia64_get_itc()))
stolentick = ia64_get_itc() - new_itm;
do_div(stolentick, NS_PER_TICK);
stolentick++;
do_div(stolen, NS_PER_TICK);
if (stolen > stolentick)
stolen = stolentick;
stolentick -= stolen;
do_div(blocked, NS_PER_TICK);
if (blocked > stolentick)
blocked = stolentick;
if (stolen > 0 || blocked > 0) {
account_steal_ticks(stolen);
account_idle_ticks(blocked);
run_local_timers();
rcu_check_callbacks(cpu, user_mode(get_irq_regs()));
scheduler_tick();
run_posix_cpu_timers(p);
delta_itm += local_cpu_data->itm_delta * (stolen + blocked);
if (cpu == time_keeper_id)
xtime_update(stolen + blocked);
local_cpu_data->itm_next = delta_itm + new_itm;
per_cpu(xen_stolen_time, cpu) += NS_PER_TICK * stolen;
per_cpu(xen_blocked_time, cpu) += NS_PER_TICK * blocked;
}
return delta_itm;
}
void tick_nohz_restart_sched_tick(void)
#endif
{
int cpu = smp_processor_id();
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
unsigned long ticks;
#endif
ktime_t now;
local_irq_disable();
if (ts->idle_active || (ts->inidle && ts->tick_stopped))
now = ktime_get();
if (ts->idle_active)
tick_nohz_stop_idle(cpu, now);
if (!ts->inidle || !ts->tick_stopped) {
ts->inidle = 0;
#ifdef CONFIG_DATAPLANE
if (!user_idle)
#endif
local_irq_enable();
return;
}
ts->inidle = 0;
rcu_exit_nohz();
/* Update jiffies first */
select_nohz_load_balancer(0);
tick_do_update_jiffies64(now);
cpumask_clear_cpu(cpu, nohz_cpu_mask);
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
/*
* We stopped the tick in idle. Update process times would miss the
* time we slept as update_process_times does only a 1 tick
* accounting. Enforce that this is accounted to idle !
*/
ticks = jiffies - ts->idle_jiffies;
/*
* We might be one off. Do not randomly account a huge number of ticks!
*/
if (ticks && ticks < LONG_MAX)
#ifdef CONFIG_DATAPLANE
{
if (user_idle) {
cputime_t cpu_time = jiffies_to_cputime(ticks);
account_user_time(current, cpu_time,
cputime_to_scaled(cpu_time));
} else {
account_idle_ticks(ticks);
}
}
#else
account_idle_ticks(ticks);
#endif
#endif
touch_softlockup_watchdog();
/*
* Cancel the scheduled timer and restore the tick
*/
ts->tick_stopped = 0;
ts->idle_exittime = now;
tick_nohz_restart(ts, now);
#ifdef CONFIG_DATAPLANE
if (!user_idle)
#endif
local_irq_enable();
}
