From 3b84bf3ce94dea82a9451a4c9c2cda37e334333c Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Wed, 11 May 2022 16:56:58 +0200 Subject: [PATCH] PM: domains: Measure suspend/resume latencies in genpd based on governor The QoS latency measurements for devices in genpd_runtime_suspend|resume() are superfluous, unless the corresponding genpd has a governor assigned to it, which would make use of the data. Therefore, let's improve the behaviour in genpd by making the measurements conditional, based upon if there's a governor assigned. Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 4c059a8..2cdfbe4 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -881,7 +881,7 @@ static int genpd_runtime_suspend(struct device *dev) struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev); struct gpd_timing_data *td = gpd_data->td; bool runtime_pm = pm_runtime_enabled(dev); - ktime_t time_start; + ktime_t time_start = 0; s64 elapsed_ns; int ret; @@ -902,8 +902,7 @@ static int genpd_runtime_suspend(struct device *dev) return -EBUSY; /* Measure suspend latency. */ - time_start = 0; - if (runtime_pm) + if (td && runtime_pm) time_start = ktime_get(); ret = __genpd_runtime_suspend(dev); @@ -917,9 +916,9 @@ static int genpd_runtime_suspend(struct device *dev) } /* Update suspend latency value if the measured time exceeds it. */ - if (runtime_pm) { + if (td && runtime_pm) { elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); - if (td && (elapsed_ns > td->suspend_latency_ns)) { + if (elapsed_ns > td->suspend_latency_ns) { td->suspend_latency_ns = elapsed_ns; dev_dbg(dev, "suspend latency exceeded, %lld ns\n", elapsed_ns); @@ -956,11 +955,10 @@ static int genpd_runtime_resume(struct device *dev) struct generic_pm_domain *genpd; struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev); struct gpd_timing_data *td = gpd_data->td; - bool runtime_pm = pm_runtime_enabled(dev); - ktime_t time_start; + bool timed = td && pm_runtime_enabled(dev); + ktime_t time_start = 0; s64 elapsed_ns; int ret; - bool timed = true; dev_dbg(dev, "%s()\n", __func__); @@ -988,8 +986,7 @@ static int genpd_runtime_resume(struct device *dev) out: /* Measure resume latency. */ - time_start = 0; - if (timed && runtime_pm) + if (timed) time_start = ktime_get(); ret = genpd_start_dev(genpd, dev); @@ -1001,9 +998,9 @@ static int genpd_runtime_resume(struct device *dev) goto err_stop; /* Update resume latency value if the measured time exceeds it. */ - if (timed && runtime_pm) { + if (timed) { elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); - if (td && (elapsed_ns > td->resume_latency_ns)) { + if (elapsed_ns > td->resume_latency_ns) { td->resume_latency_ns = elapsed_ns; dev_dbg(dev, "resume latency exceeded, %lld ns\n", elapsed_ns); -- 2.7.4