diff options
Diffstat (limited to 'drivers/cpuidle')
| -rw-r--r-- | drivers/cpuidle/coupled.c | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-powernv.c | 102 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 3 | ||||
| -rw-r--r-- | drivers/cpuidle/driver.c | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 75 |
5 files changed, 140 insertions, 44 deletions
diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c index e952936418d..cb6654bfad7 100644 --- a/drivers/cpuidle/coupled.c +++ b/drivers/cpuidle/coupled.c @@ -323,7 +323,7 @@ static void cpuidle_coupled_poke(int cpu) struct call_single_data *csd = &per_cpu(cpuidle_coupled_poke_cb, cpu); if (!cpumask_test_and_set_cpu(cpu, &cpuidle_coupled_poke_pending)) - __smp_call_function_single(cpu, csd, 0); + smp_call_function_single_async(cpu, csd); } /** diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index f48607cd254..719f6fb5b1c 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -11,11 +11,19 @@ #include <linux/cpuidle.h> #include <linux/cpu.h> #include <linux/notifier.h> +#include <linux/clockchips.h> +#include <linux/of.h> #include <asm/machdep.h> #include <asm/firmware.h> #include <asm/runlatch.h> +/* Flags and constants used in PowerNV platform */ + +#define MAX_POWERNV_IDLE_STATES 8 +#define IDLE_USE_INST_NAP 0x00010000 /* Use nap instruction */ +#define IDLE_USE_INST_SLEEP 0x00020000 /* Use sleep instruction */ + struct cpuidle_driver powernv_idle_driver = { .name = "powernv_idle", .owner = THIS_MODULE, @@ -54,10 +62,36 @@ static int nap_loop(struct cpuidle_device *dev, return index; } +static int fastsleep_loop(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + unsigned long old_lpcr = mfspr(SPRN_LPCR); + unsigned long new_lpcr; + + if (unlikely(system_state < SYSTEM_RUNNING)) + return index; + + new_lpcr = old_lpcr; + new_lpcr &= ~(LPCR_MER | LPCR_PECE); /* lpcr[mer] must be 0 */ + + /* exit powersave upon external interrupt, but not decrementer + * interrupt. + */ + new_lpcr |= LPCR_PECE0; + + mtspr(SPRN_LPCR, new_lpcr); + power7_sleep(); + + mtspr(SPRN_LPCR, old_lpcr); + + return index; +} + /* * States for dedicated partition case. */ -static struct cpuidle_state powernv_states[] = { +static struct cpuidle_state powernv_states[MAX_POWERNV_IDLE_STATES] = { { /* Snooze */ .name = "snooze", .desc = "snooze", @@ -65,13 +99,6 @@ static struct cpuidle_state powernv_states[] = { .exit_latency = 0, .target_residency = 0, .enter = &snooze_loop }, - { /* NAP */ - .name = "NAP", - .desc = "NAP", - .flags = CPUIDLE_FLAG_TIME_VALID, - .exit_latency = 10, - .target_residency = 100, - .enter = &nap_loop }, }; static int powernv_cpuidle_add_cpu_notifier(struct notifier_block *n, @@ -132,19 +159,74 @@ static int powernv_cpuidle_driver_init(void) return 0; } +static int powernv_add_idle_states(void) +{ + struct device_node *power_mgt; + struct property *prop; + int nr_idle_states = 1; /* Snooze */ + int dt_idle_states; + u32 *flags; + int i; + + /* Currently we have snooze statically defined */ + + power_mgt = of_find_node_by_path("/ibm,opal/power-mgt"); + if (!power_mgt) { + pr_warn("opal: PowerMgmt Node not found\n"); + return nr_idle_states; + } + + prop = of_find_property(power_mgt, "ibm,cpu-idle-state-flags", NULL); + if (!prop) { + pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n"); + return nr_idle_states; + } + + dt_idle_states = prop->length / sizeof(u32); + flags = (u32 *) prop->value; + + for (i = 0; i < dt_idle_states; i++) { + + if (flags[i] & IDLE_USE_INST_NAP) { + /* Add NAP state */ + strcpy(powernv_states[nr_idle_states].name, "Nap"); + strcpy(powernv_states[nr_idle_states].desc, "Nap"); + powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIME_VALID; + powernv_states[nr_idle_states].exit_latency = 10; + powernv_states[nr_idle_states].target_residency = 100; + powernv_states[nr_idle_states].enter = &nap_loop; + nr_idle_states++; + } + + if (flags[i] & IDLE_USE_INST_SLEEP) { + /* Add FASTSLEEP state */ + strcpy(powernv_states[nr_idle_states].name, "FastSleep"); + strcpy(powernv_states[nr_idle_states].desc, "FastSleep"); + powernv_states[nr_idle_states].flags = + CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TIMER_STOP; + powernv_states[nr_idle_states].exit_latency = 300; + powernv_states[nr_idle_states].target_residency = 1000000; + powernv_states[nr_idle_states].enter = &fastsleep_loop; + nr_idle_states++; + } + } + + return nr_idle_states; +} + /* * powernv_idle_probe() * Choose state table for shared versus dedicated partition */ static int powernv_idle_probe(void) { - if (cpuidle_disable != IDLE_NO_OVERRIDE) return -ENODEV; if (firmware_has_feature(FW_FEATURE_OPALv3)) { cpuidle_state_table = powernv_states; - max_idle_state = ARRAY_SIZE(powernv_states); + /* Device tree can indicate more idle states */ + max_idle_state = powernv_add_idle_states(); } else return -ENODEV; diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 166a7322a2b..8236746e46b 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -105,7 +105,8 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, time_end = ktime_get(); - local_irq_enable(); + if (!cpuidle_state_is_coupled(dev, drv, entered_state)) + local_irq_enable(); diff = ktime_to_us(ktime_sub(time_end, time_start)); if (diff > INT_MAX) diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c index 06dbe7c8619..136d6a283e0 100644 --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -209,7 +209,7 @@ static void poll_idle_init(struct cpuidle_driver *drv) state->exit_latency = 0; state->target_residency = 0; state->power_usage = -1; - state->flags = 0; + state->flags = CPUIDLE_FLAG_TIME_VALID; state->enter = poll_idle; state->disabled = false; } diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index cf7f2f0e4ef..71b52329335 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -122,9 +122,8 @@ struct menu_device { int last_state_idx; int needs_update; - unsigned int expected_us; + unsigned int next_timer_us; unsigned int predicted_us; - unsigned int exit_us; unsigned int bucket; unsigned int correction_factor[BUCKETS]; unsigned int intervals[INTERVALS]; @@ -257,7 +256,7 @@ again: stddev = int_sqrt(stddev); if (((avg > stddev * 6) && (divisor * 4 >= INTERVALS * 3)) || stddev <= 20) { - if (data->expected_us > avg) + if (data->next_timer_us > avg) data->predicted_us = avg; return; } @@ -289,7 +288,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) struct menu_device *data = &__get_cpu_var(menu_devices); int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); int i; - int multiplier; + unsigned int interactivity_req; struct timespec t; if (data->needs_update) { @@ -298,7 +297,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) } data->last_state_idx = 0; - data->exit_us = 0; /* Special case when user has set very strict latency requirement */ if (unlikely(latency_req == 0)) @@ -306,13 +304,11 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) /* determine the expected residency time, round up */ t = ktime_to_timespec(tick_nohz_get_sleep_length()); - data->expected_us = + data->next_timer_us = t.tv_sec * USEC_PER_SEC + t.tv_nsec / NSEC_PER_USEC; - data->bucket = which_bucket(data->expected_us); - - multiplier = performance_multiplier(); + data->bucket = which_bucket(data->next_timer_us); /* * if the correction factor is 0 (eg first time init or cpu hotplug @@ -326,17 +322,26 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) * operands are 32 bits. * Make sure to round up for half microseconds. */ - data->predicted_us = div_round64((uint64_t)data->expected_us * + data->predicted_us = div_round64((uint64_t)data->next_timer_us * data->correction_factor[data->bucket], RESOLUTION * DECAY); get_typical_interval(data); /* + * Performance multiplier defines a minimum predicted idle + * duration / latency ratio. Adjust the latency limit if + * necessary. + */ + interactivity_req = data->predicted_us / performance_multiplier(); + if (latency_req > interactivity_req) + latency_req = interactivity_req; + + /* * We want to default to C1 (hlt), not to busy polling * unless the timer is happening really really soon. */ - if (data->expected_us > 5 && + if (data->next_timer_us > 5 && !drv->states[CPUIDLE_DRIVER_STATE_START].disabled && dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable == 0) data->last_state_idx = CPUIDLE_DRIVER_STATE_START; @@ -355,11 +360,8 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) continue; if (s->exit_latency > latency_req) continue; - if (s->exit_latency * multiplier > data->predicted_us) - continue; data->last_state_idx = i; - data->exit_us = s->exit_latency; } return data->last_state_idx; @@ -390,36 +392,47 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct menu_device *data = &__get_cpu_var(menu_devices); int last_idx = data->last_state_idx; - unsigned int last_idle_us = cpuidle_get_last_residency(dev); struct cpuidle_state *target = &drv->states[last_idx]; unsigned int measured_us; unsigned int new_factor; /* - * Ugh, this idle state doesn't support residency measurements, so we - * are basically lost in the dark. As a compromise, assume we slept - * for the whole expected time. + * Try to figure out how much time passed between entry to low + * power state and occurrence of the wakeup event. + * + * If the entered idle state didn't support residency measurements, + * we are basically lost in the dark how much time passed. + * As a compromise, assume we slept for the whole expected time. + * + * Any measured amount of time will include the exit latency. + * Since we are interested in when the wakeup begun, not when it + * was completed, we must substract the exit latency. However, if + * the measured amount of time is less than the exit latency, + * assume the state was never reached and the exit latency is 0. */ - if (unlikely(!(target->flags & CPUIDLE_FLAG_TIME_VALID))) - last_idle_us = data->expected_us; + if (unlikely(!(target->flags & CPUIDLE_FLAG_TIME_VALID))) { + /* Use timer value as is */ + measured_us = data->next_timer_us; + } else { + /* Use measured value */ + measured_us = cpuidle_get_last_residency(dev); - measured_us = last_idle_us; - - /* - * We correct for the exit latency; we are assuming here that the - * exit latency happens after the event that we're interested in. - */ - if (measured_us > data->exit_us) - measured_us -= data->exit_us; + /* Deduct exit latency */ + if (measured_us > target->exit_latency) + measured_us -= target->exit_latency; + /* Make sure our coefficients do not exceed unity */ + if (measured_us > data->next_timer_us) + measured_us = data->next_timer_us; + } /* Update our correction ratio */ new_factor = data->correction_factor[data->bucket]; new_factor -= new_factor / DECAY; - if (data->expected_us > 0 && measured_us < MAX_INTERESTING) - new_factor += RESOLUTION * measured_us / data->expected_us; + if (data->next_timer_us > 0 && measured_us < MAX_INTERESTING) + new_factor += RESOLUTION * measured_us / data->next_timer_us; else /* * we were idle so long that we count it as a perfect @@ -439,7 +452,7 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev) data->correction_factor[data->bucket] = new_factor; /* update the repeating-pattern data */ - data->intervals[data->interval_ptr++] = last_idle_us; + data->intervals[data->interval_ptr++] = measured_us; if (data->interval_ptr >= INTERVALS) data->interval_ptr = 0; } |