In order to prevent a pointless forward declaration, just move the function at the beginning of the file.
This patch does not change the behavior of the governor, it is just code reordering.
Signed-off-by: Daniel Lezcano daniel.lezcano@linaro.org --- drivers/cpuidle/governors/menu.c | 149 +++++++++++++++++++-------------------- 1 file changed, 74 insertions(+), 75 deletions(-)
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 6ae8390..0ac76b1 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -184,7 +184,6 @@ static inline int performance_multiplier(unsigned long nr_iowaiters, unsigned lo
static DEFINE_PER_CPU(struct menu_device, menu_devices);
-static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev);
/* This implements DIV_ROUND_CLOSEST but avoids 64 bit division */ static u64 div_round64(u64 dividend, u32 divisor) @@ -192,6 +191,80 @@ static u64 div_round64(u64 dividend, u32 divisor) return div_u64(dividend + (divisor / 2), divisor); }
+/** + * menu_update - attempts to guess what happened after entry + * @drv: cpuidle driver containing state data + * @dev: the CPU + */ +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; + struct cpuidle_state *target = &drv->states[last_idx]; + unsigned int measured_us; + unsigned int new_factor; + + /* + * 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 subtract 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))) { + /* Use timer value as is */ + measured_us = data->next_timer_us; + + } else { + /* Use measured value */ + measured_us = cpuidle_get_last_residency(dev); + + /* 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->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 + * prediction + */ + new_factor += RESOLUTION; + + /* + * We don't want 0 as factor; we always want at least + * a tiny bit of estimated time. Fortunately, due to rounding, + * new_factor will stay nonzero regardless of measured_us values + * and the compiler can eliminate this test as long as DECAY > 1. + */ + if (DECAY == 1 && unlikely(new_factor == 0)) + new_factor = 1; + + data->correction_factor[data->bucket] = new_factor; + + /* update the repeating-pattern data */ + data->intervals[data->interval_ptr++] = measured_us; + if (data->interval_ptr >= INTERVALS) + data->interval_ptr = 0; +} + /* * Try detecting repeating patterns by keeping track of the last 8 * intervals, and checking if the standard deviation of that set @@ -378,80 +451,6 @@ static void menu_reflect(struct cpuidle_device *dev, int index) }
/** - * menu_update - attempts to guess what happened after entry - * @drv: cpuidle driver containing state data - * @dev: the CPU - */ -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; - struct cpuidle_state *target = &drv->states[last_idx]; - unsigned int measured_us; - unsigned int new_factor; - - /* - * 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 subtract 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))) { - /* Use timer value as is */ - measured_us = data->next_timer_us; - - } else { - /* Use measured value */ - measured_us = cpuidle_get_last_residency(dev); - - /* 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->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 - * prediction - */ - new_factor += RESOLUTION; - - /* - * We don't want 0 as factor; we always want at least - * a tiny bit of estimated time. Fortunately, due to rounding, - * new_factor will stay nonzero regardless of measured_us values - * and the compiler can eliminate this test as long as DECAY > 1. - */ - if (DECAY == 1 && unlikely(new_factor == 0)) - new_factor = 1; - - data->correction_factor[data->bucket] = new_factor; - - /* update the repeating-pattern data */ - data->intervals[data->interval_ptr++] = measured_us; - if (data->interval_ptr >= INTERVALS) - data->interval_ptr = 0; -} - -/** * menu_enable_device - scans a CPU's states and does setup * @drv: cpuidle driver * @dev: the CPU