static int snooze_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
unsigned long in_purr;
int cpu = dev->cpu;
idle_loop_prolog(&in_purr);
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
while ((!need_resched()) && cpu_online(cpu)) {
ppc64_runlatch_off();
HMT_low();
HMT_very_low();
}
HMT_medium();
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
idle_loop_epilog(in_purr);
return index;
}
static void iseries_shared_idle(void)
{
while (1) {
tick_nohz_stop_sched_tick(1);
while (!need_resched() && !hvlpevent_is_pending()) {
local_irq_disable();
ppc64_runlatch_off();
/* Recheck with irqs off */
if (!need_resched() && !hvlpevent_is_pending())
yield_shared_processor();
HMT_medium();
local_irq_enable();
}
ppc64_runlatch_on();
tick_nohz_restart_sched_tick();
if (hvlpevent_is_pending())
process_iSeries_events();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
static void iseries_dedicated_idle(void)
{
set_thread_flag(TIF_POLLING_NRFLAG);
while (1) {
tick_nohz_stop_sched_tick(1);
if (!need_resched()) {
while (!need_resched()) {
ppc64_runlatch_off();
HMT_low();
if (hvlpevent_is_pending()) {
HMT_medium();
ppc64_runlatch_on();
process_iSeries_events();
}
}
HMT_medium();
}
ppc64_runlatch_on();
tick_nohz_restart_sched_tick();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
/*
* The body of the idle task.
*/
void cpu_idle(void)
{
if (ppc_md.idle_loop)
ppc_md.idle_loop(); /* doesn't return */
set_thread_flag(TIF_POLLING_NRFLAG);
while (1) {
tick_nohz_idle_enter();
rcu_idle_enter();
while (!need_resched() && !cpu_should_die()) {
ppc64_runlatch_off();
if (ppc_md.power_save) {
clear_thread_flag(TIF_POLLING_NRFLAG);
/*
* smp_mb is so clearing of TIF_POLLING_NRFLAG
* is ordered w.r.t. need_resched() test.
*/
smp_mb();
local_irq_disable();
/* Don't trace irqs off for idle */
stop_critical_timings();
/* check again after disabling irqs */
if (!need_resched() && !cpu_should_die())
ppc_md.power_save();
start_critical_timings();
/* Some power_save functions return with
* interrupts enabled, some don't.
*/
if (irqs_disabled())
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
} else {
/*
* Go into low thread priority and possibly
* low power mode.
*/
HMT_low();
HMT_very_low();
}
}
HMT_medium();
ppc64_runlatch_on();
rcu_idle_exit();
tick_nohz_idle_exit();
if (cpu_should_die()) {
sched_preempt_enable_no_resched();
cpu_die();
}
schedule_preempt_disabled();
}
}
/*
* The body of the idle task.
*/
void cpu_idle(void)
{
if (ppc_md.idle_loop)
ppc_md.idle_loop(); /* doesn't return */
set_thread_flag(TIF_POLLING_NRFLAG);
while (1) {
hrtimer_stop_sched_tick();
while (!need_resched() && !need_resched_delayed() &&
!cpu_should_die()) {
ppc64_runlatch_off();
/*
*
* We have irqs disabled here, so stop latency tracing
* at this point and restart it after we return:
*/
stop_critical_timing();
if (ppc_md.power_save) {
clear_thread_flag(TIF_POLLING_NRFLAG);
/*
* smp_mb is so clearing of TIF_POLLING_NRFLAG
* is ordered w.r.t. need_resched() test.
*/
smp_mb();
local_irq_disable();
/* check again after disabling irqs */
if (!need_resched() && !cpu_should_die())
ppc_md.power_save();
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
} else {
/*
* Go into low thread priority and possibly
* low power mode.
*/
HMT_low();
HMT_very_low();
}
touch_critical_timing();
}
HMT_medium();
ppc64_runlatch_on();
if (cpu_should_die())
cpu_die();
hrtimer_restart_sched_tick();
__preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
static int nap_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
ppc64_runlatch_off();
power7_idle();
ppc64_runlatch_on();
return index;
}
static inline void idle_loop_prolog(unsigned long *in_purr)
{
ppc64_runlatch_off();
*in_purr = mfspr(SPRN_PURR);
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
get_lppaca()->idle = 1;
}
static int pseries_dedicated_idle(void)
{
long oldval;
struct paca_struct *lpaca = get_paca();
unsigned int cpu = smp_processor_id();
unsigned long start_snooze;
unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay);
while (1) {
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
lpaca->lppaca.idle = 1;
oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
if (!oldval) {
set_thread_flag(TIF_POLLING_NRFLAG);
start_snooze = __get_tb() +
*smt_snooze_delay * tb_ticks_per_usec;
while (!need_resched() && !cpu_is_offline(cpu)) {
ppc64_runlatch_off();
/*
* Go into low thread priority and possibly
* low power mode.
*/
HMT_low();
HMT_very_low();
if (*smt_snooze_delay != 0 &&
__get_tb() > start_snooze) {
HMT_medium();
dedicated_idle_sleep(cpu);
}
}
HMT_medium();
clear_thread_flag(TIF_POLLING_NRFLAG);
} else {
set_need_resched();
}
lpaca->lppaca.idle = 0;
ppc64_runlatch_on();
schedule();
if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
cpu_die();
}
}
static void pseries_dedicated_idle_sleep(void)
{
unsigned int cpu = smp_processor_id();
unsigned long start_snooze;
unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay);
unsigned long in_purr, out_purr;
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
get_lppaca()->idle = 1;
get_lppaca()->cpuctls_task_attrs = 1;
in_purr = mfspr(SPRN_PURR);
/*
* We come in with interrupts disabled, and need_resched()
* has been checked recently. If we should poll for a little
* while, do so.
*/
if (*smt_snooze_delay) {
start_snooze = get_tb() +
*smt_snooze_delay * tb_ticks_per_usec;
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
while (get_tb() < start_snooze) {
if (need_resched() || cpu_is_offline(cpu))
goto out;
ppc64_runlatch_off();
HMT_low();
HMT_very_low();
}
HMT_medium();
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
local_irq_disable();
if (need_resched() || cpu_is_offline(cpu))
goto out;
}
cede_processor();
out:
HMT_medium();
get_lppaca()->cpuctls_task_attrs = 0;
out_purr = mfspr(SPRN_PURR);
get_lppaca()->wait_state_cycles += out_purr - in_purr;
get_lppaca()->idle = 0;
}
void cpu_idle(void)
{
if (ppc_md.idle_loop)
ppc_md.idle_loop();
set_thread_flag(TIF_POLLING_NRFLAG);
while (1) {
tick_nohz_idle_enter();
rcu_idle_enter();
while (!need_resched() && !cpu_should_die()) {
ppc64_runlatch_off();
if (ppc_md.power_save) {
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
local_irq_disable();
stop_critical_timings();
if (!need_resched() && !cpu_should_die())
ppc_md.power_save();
start_critical_timings();
if (irqs_disabled())
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
} else {
HMT_low();
HMT_very_low();
}
}
HMT_medium();
ppc64_runlatch_on();
rcu_idle_exit();
tick_nohz_idle_exit();
if (cpu_should_die()) {
sched_preempt_enable_no_resched();
cpu_die();
}
schedule_preempt_disabled();
}
}
/*
* The body of the idle task.
*/
void cpu_idle(void)
{
if (ppc_md.idle_loop)
ppc_md.idle_loop(); /* doesn't return */
set_thread_flag(TIF_POLLING_NRFLAG);
while (1) {
tick_nohz_stop_sched_tick();
while (!need_resched() && !cpu_should_die()) {
ppc64_runlatch_off();
if (ppc_md.power_save) {
clear_thread_flag(TIF_POLLING_NRFLAG);
/*
* smp_mb is so clearing of TIF_POLLING_NRFLAG
* is ordered w.r.t. need_resched() test.
*/
smp_mb();
local_irq_disable();
/* check again after disabling irqs */
if (!need_resched() && !cpu_should_die())
ppc_md.power_save();
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
} else {
/*
* Go into low thread priority and possibly
* low power mode.
*/
HMT_low();
HMT_very_low();
}
}
HMT_medium();
ppc64_runlatch_on();
tick_nohz_restart_sched_tick();
if (cpu_should_die())
cpu_die();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
static int pseries_shared_idle(void)
{
struct paca_struct *lpaca = get_paca();
unsigned int cpu = smp_processor_id();
while (1) {
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
lpaca->lppaca.idle = 1;
while (!need_resched() && !cpu_is_offline(cpu)) {
local_irq_disable();
ppc64_runlatch_off();
/*
* Yield the processor to the hypervisor. We return if
* an external interrupt occurs (which are driven prior
* to returning here) or if a prod occurs from another
* processor. When returning here, external interrupts
* are enabled.
*
* Check need_resched() again with interrupts disabled
* to avoid a race.
*/
if (!need_resched())
cede_processor();
else
local_irq_enable();
HMT_medium();
}
lpaca->lppaca.idle = 0;
ppc64_runlatch_on();
schedule();
if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
cpu_die();
}
return 0;
}
static int dedicated_cede_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
unsigned long in_purr;
ktime_t kt_before;
idle_loop_prolog(&in_purr, &kt_before);
get_lppaca()->donate_dedicated_cpu = 1;
ppc64_runlatch_off();
HMT_medium();
check_and_cede_processor();
get_lppaca()->donate_dedicated_cpu = 0;
dev->last_residency =
(int)idle_loop_epilog(in_purr, kt_before);
return index;
}
static int snooze_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
ppc64_runlatch_off();
while (!need_resched()) {
HMT_low();
HMT_very_low();
}
HMT_medium();
ppc64_runlatch_on();
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
return index;
}
static int dedicated_cede_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
unsigned long in_purr;
idle_loop_prolog(&in_purr);
get_lppaca()->donate_dedicated_cpu = 1;
ppc64_runlatch_off();
HMT_medium();
check_and_cede_processor();
get_lppaca()->donate_dedicated_cpu = 0;
idle_loop_epilog(in_purr);
return index;
}
static int snooze_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
u64 snooze_exit_time;
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
snooze_exit_time = get_tb() + snooze_timeout;
ppc64_runlatch_off();
while (!need_resched()) {
HMT_low();
HMT_very_low();
if (snooze_timeout_en && get_tb() > snooze_exit_time)
break;
}
HMT_medium();
ppc64_runlatch_on();
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
return index;
}
static int snooze_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
unsigned long in_purr;
ktime_t kt_before;
unsigned long start_snooze;
long snooze = drv->states[0].target_residency;
idle_loop_prolog(&in_purr, &kt_before);
if (snooze) {
start_snooze = get_tb() + snooze * tb_ticks_per_usec;
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
while ((snooze < 0) || (get_tb() < start_snooze)) {
if (need_resched() || cpu_is_offline(dev->cpu))
goto out;
ppc64_runlatch_off();
HMT_low();
HMT_very_low();
}
HMT_medium();
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb();
local_irq_disable();
}
out:
HMT_medium();
dev->last_residency =
(int)idle_loop_epilog(in_purr, kt_before);
return index;
}
static void pnv_smp_cpu_kill_self(void)
{
unsigned int cpu;
/* Standard hot unplug procedure */
local_irq_disable();
idle_task_exit();
current->active_mm = NULL; /* for sanity */
cpu = smp_processor_id();
DBG("CPU%d offline\n", cpu);
generic_set_cpu_dead(cpu);
smp_wmb();
/* We don't want to take decrementer interrupts while we are offline,
* so clear LPCR:PECE1. We keep PECE2 enabled.
*/
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
while (!generic_check_cpu_restart(cpu)) {
ppc64_runlatch_off();
power7_nap(1);
ppc64_runlatch_on();
/* Reenable IRQs briefly to clear the IPI that woke us */
local_irq_enable();
local_irq_disable();
mb();
if (cpu_core_split_required())
continue;
if (!generic_check_cpu_restart(cpu))
DBG("CPU%d Unexpected exit while offline !\n", cpu);
}
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);
DBG("CPU%d coming online...\n", cpu);
}
