В Thu, 18 Jul 2019 18:48:42 +0900 Chanwoo Choi <[email protected]> пишет:
> On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: > > When CPU's memory activity is low or memory activity is high such > > that CPU's frequency contribution to the boosting is not taken into > > account, then there is no need to schedule devfreq's update. This > > eliminates unnecessary CPU activity during of idling caused by the > > scheduled work. > > > > Signed-off-by: Dmitry Osipenko <[email protected]> > > --- > > drivers/devfreq/tegra30-devfreq.c | 73 > > +++++++++++++++++++++++++++---- 1 file changed, 64 insertions(+), 9 > > deletions(-) > > Patch4 add the 'cpufreq notifier' and this patch optimize the cpufreq > notifier. I think t hat you can combine two patches. I'd prefer to keep them separate for a sake of git bisection. > > > > diff --git a/drivers/devfreq/tegra30-devfreq.c > > b/drivers/devfreq/tegra30-devfreq.c index > > 43c9c5fbfe91..8d6bf6e9f1ae 100644 --- > > a/drivers/devfreq/tegra30-devfreq.c +++ > > b/drivers/devfreq/tegra30-devfreq.c @@ -216,10 +216,10 @@ static > > inline unsigned long do_percent(unsigned long val, unsigned int > > pct) return val * pct / 100; } > > > > -static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq > > *tegra) +static unsigned long actmon_cpu_to_emc_rate(struct > > tegra_devfreq *tegra, > > + unsigned int cpu_freq) > > { > > const struct tegra_actmon_emc_ratio *ratio = > > actmon_emc_ratios; > > - unsigned int cpu_freq = cpufreq_get(0); > > unsigned int i; > > > > for (i = 0; i < ARRAY_SIZE(actmon_emc_ratios); i++, > > ratio++) { @@ -239,15 +239,15 @@ > > tegra_actmon_account_cpu_freq(struct tegra_devfreq *tegra, struct > > tegra_devfreq_device *dev, unsigned long target_freq) > > { > > - unsigned long static_cpu_emc_freq; > > + unsigned long cpu_emc_freq = 0; > > > > - if (dev->config->avg_dependency_threshold && > > - dev->config->avg_dependency_threshold < dev->avg_freq) > > { > > - static_cpu_emc_freq = > > actmon_cpu_to_emc_rate(tegra); > > - target_freq = max(target_freq, > > static_cpu_emc_freq); > > - } > > + if (!dev->config->avg_dependency_threshold) > > + return target_freq; > > > > - return target_freq; > > + if (dev->avg_freq > dev->config->avg_dependency_threshold) > > + cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, > > cpufreq_get(0)); + > > + return max(target_freq, cpu_emc_freq); > > } > > > > static unsigned long tegra_actmon_lower_freq(struct tegra_devfreq > > *tegra, @@ -531,16 +531,71 @@ static void > > tegra_actmon_delayed_update(struct work_struct *work) > > mutex_unlock(&tegra->devfreq->lock); } > > > > +static unsigned long > > +tegra_actmon_cpufreq_contribution(struct tegra_devfreq *tegra, > > + unsigned int cpu_freq) > > +{ > > + unsigned long freq, static_cpu_emc_freq; > > + > > + /* check whether CPU's freq is taken into account at all */ > > + if (tegra->devices[MCCPU].avg_freq <= > > + tegra->devices[MCCPU].config->avg_dependency_threshold) > > + return 0; > > + > > + static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, > > cpu_freq); + > > + /* compare static CPU-EMC freq with MCALL */ > > + freq = tegra->devices[MCALL].avg_freq + > > + tegra->devices[MCALL].boost_freq; > > + > > + freq = tegra_actmon_upper_freq(tegra, freq); > > + > > + if (freq == tegra->max_freq || freq >= static_cpu_emc_freq) > > + return 0; > > + > > + /* compare static CPU-EMC freq with MCCPU */ > > + freq = tegra->devices[MCCPU].avg_freq + > > + tegra->devices[MCCPU].boost_freq; > > + > > + freq = tegra_actmon_upper_freq(tegra, freq); > > + > > + if (freq == tegra->max_freq || freq >= static_cpu_emc_freq) > > + return 0; > > + > > + return static_cpu_emc_freq; > > +} > > + > > static int tegra_actmon_cpu_notify_cb(struct notifier_block *nb, > > unsigned long action, void > > *ptr) { > > + struct cpufreq_freqs *freqs = ptr; > > struct tegra_devfreq *tegra; > > + unsigned long old, new; > > > > if (action != CPUFREQ_POSTCHANGE) > > return NOTIFY_OK; > > > > tegra = container_of(nb, struct tegra_devfreq, > > cpu_rate_change_nb); > > + /* > > + * Quickly check whether CPU frequency should be taken > > into account > > + * at all, without blocking CPUFreq's core. > > + */ > > + if (mutex_trylock(&tegra->devfreq->lock)) { > > + old = tegra_actmon_cpufreq_contribution(tegra, > > freqs->old); > > + new = tegra_actmon_cpufreq_contribution(tegra, > > freqs->new); > > + mutex_unlock(&tegra->devfreq->lock); > > + > > + /* > > + * If CPU's frequency shouldn't be taken into > > account at > > + * the moment, then there is no need to update the > > devfreq's > > + * state because ISR will re-check CPU's frequency > > on the > > + * next interrupt. > > + */ > > + if (old == new) > > + return NOTIFY_OK; > > + } > > + > > /* > > * CPUFreq driver should support > > CPUFREQ_ASYNC_NOTIFICATION in order > > * to allow asynchronous notifications. This means we > > can't block > >
