From 89b1f0af2394edaa1675092a0d9f1cc30cba4d72 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 27 Nov 2011 13:12:25 +0100 Subject: [PATCH] PM / Domains: Automatically update overoptimistic latency information Measure the time of execution of the .stop(), .start(), .save_state() and .restore_state() PM domain device callbacks and if the result is greater than the corresponding latency value stored in the device's struct generic_pm_domain_data object, replace the inaccurate value with the measured time. Do analogously for the PM domains' .power_off() and .power_off() callbacks. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 43 +++++++++++++++++++++++++++++++++---- 1 file changed, 39 insertions(+), 4 deletions(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 91896194e76b..5a8d67d51f0e 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -33,6 +33,20 @@ __ret; \ }) +#define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name) \ +({ \ + ktime_t __start = ktime_get(); \ + type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \ + s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \ + struct generic_pm_domain_data *__gpd_data = dev_gpd_data(dev); \ + if (__elapsed > __gpd_data->td.field) { \ + __gpd_data->td.field = __elapsed; \ + dev_warn(dev, name " latency exceeded, new value %lld ns\n", \ + __elapsed); \ + } \ + __retval; \ +}) + static LIST_HEAD(gpd_list); static DEFINE_MUTEX(gpd_list_lock); @@ -48,22 +62,27 @@ struct generic_pm_domain *dev_to_genpd(struct device *dev) static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, stop, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev, + stop_latency_ns, "stop"); } static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, start, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev, + start_latency_ns, "start"); } static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, save_state, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev, + save_state_latency_ns, "state save"); } static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev, + restore_state_latency_ns, + "state restore"); } static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd) @@ -182,9 +201,16 @@ int __pm_genpd_poweron(struct generic_pm_domain *genpd) } if (genpd->power_on) { + ktime_t time_start = ktime_get(); + s64 elapsed_ns; + ret = genpd->power_on(genpd); if (ret) goto err; + + elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); + if (elapsed_ns > genpd->power_on_latency_ns) + genpd->power_on_latency_ns = elapsed_ns; } genpd_set_active(genpd); @@ -377,11 +403,16 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) } if (genpd->power_off) { + ktime_t time_start; + s64 elapsed_ns; + if (atomic_read(&genpd->sd_count) > 0) { ret = -EBUSY; goto out; } + time_start = ktime_get(); + /* * If sd_count > 0 at this point, one of the subdomains hasn't * managed to call pm_genpd_poweron() for the master yet after @@ -395,6 +426,10 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) genpd_set_active(genpd); goto out; } + + elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); + if (elapsed_ns > genpd->power_off_latency_ns) + genpd->power_off_latency_ns = elapsed_ns; } genpd->status = GPD_STATE_POWER_OFF; -- 2.39.5