В Thu, 18 Jul 2019 19:17:17 +0900 Chanwoo Choi <[email protected]> пишет:
> On 19. 7. 8. 오전 7:32, Dmitry Osipenko wrote: > > The current implementation is inaccurate and results in very > > intensive interrupt activity, which neglects the whole idea of > > polling offload to hardware. The reason of the shortcoming is that > > watermarks are not set up correctly and this results in ACTMON > > constantly asking to change freq and then these requests are > > ignored. The end result of this patch is that there are few > > hundreds of ACTMON's interrupts instead of tens thousands after few > > minutes of a working devfreq, meanwhile the transitions activity > > stays about the same and governor becomes more reactive. > > > > Since watermarks are set precisely correct now, the boosting logic > > is changed a tad to accommodate the change. The "average sustain > > coefficient" multiplier is gone now since there is no need to > > compensate the improper watermarks and EMC frequency-bump happens > > once boosting hits the upper watermark enough times, depending on > > the per-device boosting threshold. > > > > Signed-off-by: Dmitry Osipenko <[email protected]> > > --- > > drivers/devfreq/tegra30-devfreq.c | 293 > > +++++++++++++++++++++--------- 1 file changed, 209 insertions(+), > > 84 deletions(-) > > > > diff --git a/drivers/devfreq/tegra30-devfreq.c > > b/drivers/devfreq/tegra30-devfreq.c index > > 4be7858c33bc..16f7e6cf3b99 100644 --- > > a/drivers/devfreq/tegra30-devfreq.c +++ > > b/drivers/devfreq/tegra30-devfreq.c @@ -47,6 +47,8 @@ > > > > #define ACTMON_DEV_INTR_CONSECUTIVE_UPPER > > BIT(31) #define > > ACTMON_DEV_INTR_CONSECUTIVE_LOWER BIT(30) > > +#define > > ACTMON_DEV_INTR_AVG_BELOW_WMARK > > BIT(25) +#define > > ACTMON_DEV_INTR_AVG_ABOVE_WMARK > > BIT(24) #define > > ACTMON_ABOVE_WMARK_WINDOW 1 #define > > ACTMON_BELOW_WMARK_WINDOW 3 @@ -63,9 > > +65,8 @@ > > * ACTMON_AVERAGE_WINDOW_LOG2: default value for @DEV_CTRL_K_VAL, > > which > > * translates to 2 ^ (K_VAL + 1). ex: 2 ^ (6 + 1) = 128 > > */ > > -#define ACTMON_AVERAGE_WINDOW_LOG2 6 > > -#define ACTMON_SAMPLING_PERIOD > > 12 /* ms */ -#define > > ACTMON_DEFAULT_AVG_BAND 6 /* 1/10 > > of % */ +#define > > ACTMON_AVERAGE_WINDOW_LOG2 6 > > +#define > > ACTMON_SAMPLING_PERIOD 12 /* > > ms */ #define > > KHZ 1000 @@ > > -142,9 +143,6 @@ struct tegra_devfreq_device { > > * watermark breaches. > > */ > > unsigned long boost_freq; > > - > > - /* Optimal frequency calculated from the stats for this > > device */ > > - unsigned long target_freq; > > }; > > > > struct tegra_devfreq { > > @@ -156,7 +154,6 @@ struct tegra_devfreq { > > > > struct clk *emc_clock; > > unsigned long max_freq; > > - unsigned long cur_freq; > > struct notifier_block rate_change_nb; > > > > struct tegra_devfreq_device > > devices[ARRAY_SIZE(actmon_device_configs)]; @@ -205,42 +202,182 @@ > > static 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) +{ > > + 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++) { > > + if (cpu_freq >= ratio->cpu_freq) { > > + if (ratio->emc_freq >= tegra->max_freq) > > + return tegra->max_freq; > > + else > > + return ratio->emc_freq; > > + } > > + } > > + > > + return 0; > > +} > > + > > +static unsigned long > > +tegra_actmon_account_cpu_freq(struct tegra_devfreq *tegra, > > + struct tegra_devfreq_device *dev, > > + unsigned long target_freq) > > +{ > > + unsigned long static_cpu_emc_freq; > > + > > + if (dev->config->avg_dependency_threshold && > > + dev->config->avg_dependency_threshold < > > dev->avg_count) { > > + static_cpu_emc_freq = > > actmon_cpu_to_emc_rate(tegra); > > + target_freq = max(target_freq, > > static_cpu_emc_freq); > > + } > > + > > + return target_freq; > > +} > > + > > +static unsigned long tegra_actmon_lower_freq(struct tegra_devfreq > > *tegra, > > + unsigned long > > target_freq) +{ > > + unsigned long lower = target_freq; > > + struct dev_pm_opp *opp; > > + > > + opp = > > dev_pm_opp_find_freq_floor(tegra->devfreq->dev.parent, &lower); > > + if (IS_ERR(opp)) > > + lower = 0; > > + else > > + dev_pm_opp_put(opp); > > + > > + return lower; > > +} > > + > > +static unsigned long tegra_actmon_upper_freq(struct tegra_devfreq > > *tegra, > > + unsigned long > > target_freq) +{ > > + unsigned long upper = target_freq + 1; > > + struct dev_pm_opp *opp; > > + > > + opp = > > dev_pm_opp_find_freq_ceil(tegra->devfreq->dev.parent, &upper); > > + if (IS_ERR(opp)) > > + upper = ULONG_MAX; > > + else > > + dev_pm_opp_put(opp); > > + > > + return upper; > > +} > > + > > +static void tegra_actmon_get_lower_upper(struct tegra_devfreq > > *tegra, > > + struct > > tegra_devfreq_device *dev, > > + unsigned long target_freq, > > + unsigned long *lower, > > + unsigned long *upper) > > +{ > > + /* > > + * Memory frequencies are guaranteed to have 1MHz > > granularity > > + * and thus we need this rounding down to get a proper > > watermarks > > + * range in a case where target_freq falls into a range of > > + * next_possible_opp_freq - 1MHz. > > + */ > > + target_freq = round_down(target_freq, 1000000); > > + > > + /* watermarks are set at the borders of the corresponding > > OPPs */ > > + *lower = tegra_actmon_lower_freq(tegra, target_freq); > > + *upper = tegra_actmon_upper_freq(tegra, target_freq); > > + > > + *lower /= KHZ; > > + *upper /= KHZ; > > + > > + /* > > + * The upper watermark should take into account CPU's > > frequency > > + * because cpu_to_emc_rate() may override the target_freq > > with > > + * a higher value and thus upper watermark need to be set > > up > > + * accordingly to avoid parasitic upper-events. > > + */ > > + *upper = tegra_actmon_account_cpu_freq(tegra, dev, *upper); > > + > > + *lower *= ACTMON_SAMPLING_PERIOD; > > + *upper *= ACTMON_SAMPLING_PERIOD; > > +} > > + > > static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq > > *tegra, struct tegra_devfreq_device *dev) > > { > > - u32 avg = dev->avg_count; > > - u32 avg_band_freq = tegra->max_freq * > > ACTMON_DEFAULT_AVG_BAND / KHZ; > > - u32 band = avg_band_freq * ACTMON_SAMPLING_PERIOD; > > + unsigned long lower, upper, freq; > > > > - device_writel(dev, avg + band, ACTMON_DEV_AVG_UPPER_WMARK); > > + freq = dev->avg_count / ACTMON_SAMPLING_PERIOD * KHZ; > > + tegra_actmon_get_lower_upper(tegra, dev, freq, &lower, > > &upper); > > - avg = max(dev->avg_count, band); > > - device_writel(dev, avg - band, ACTMON_DEV_AVG_LOWER_WMARK); > > + /* > > + * We want to get interrupts when MCCPU client crosses the > > + * dependency threshold in order to take into / out of > > account > > + * the CPU's freq. > > + */ > > + if (lower < dev->config->avg_dependency_threshold && > > + upper > dev->config->avg_dependency_threshold) { > > + if (dev->avg_count < > > dev->config->avg_dependency_threshold) > > + upper = > > dev->config->avg_dependency_threshold; > > + else > > + lower = > > dev->config->avg_dependency_threshold; > > + } > > + > > + device_writel(dev, lower, ACTMON_DEV_AVG_LOWER_WMARK); > > + device_writel(dev, upper, ACTMON_DEV_AVG_UPPER_WMARK); > > } > > > > static void tegra_devfreq_update_wmark(struct tegra_devfreq *tegra, > > - struct tegra_devfreq_device > > *dev) > > + struct tegra_devfreq_device > > *dev, > > + unsigned long freq) > > { > > - u32 val = tegra->cur_freq * ACTMON_SAMPLING_PERIOD; > > + unsigned long lower, upper, delta; > > + > > + /* > > + * Boosting logic kicks-in once lower / upper watermark is > > hit. > > + * The watermarks are based on the updated EMC rate and the > > + * average activity. > > + * > > + * The higher watermark is set in accordance to the EMC > > rate > > + * because we want to set it to the highest mark here and > > EMC rate > > + * represents that mark. The consecutive-upper interrupts > > are > > + * always enabled and we don't want to receive them if > > they won't > > + * do anything useful, hence the upper watermark is capped > > to maximum. > > + * Note that the EMC rate is changed once boosting pushed > > the rate > > + * too high, in that case boosting-up will be stopped > > because > > + * upper watermark is much higher now and it is > > *important* to > > + * stop the unwanted interrupts. > > + */ > > + tegra_actmon_get_lower_upper(tegra, dev, freq - 1, &lower, > > &upper); + > > + delta = do_percent(upper - lower, > > dev->config->boost_up_threshold); > > + device_writel(dev, lower + delta, ACTMON_DEV_UPPER_WMARK); > > > > - device_writel(dev, do_percent(val, > > dev->config->boost_up_threshold), > > - ACTMON_DEV_UPPER_WMARK); > > + /* > > + * Meanwhile the lower mark is based on the average value > > + * because it is the lowest possible consecutive-mark for > > this > > + * device. Once that mark is hit and boosting is stopped, > > the > > + * interrupt is disabled by ISR. > > + */ > > + freq = dev->avg_count / ACTMON_SAMPLING_PERIOD * KHZ; > > + tegra_actmon_get_lower_upper(tegra, dev, freq, &lower, > > &upper); > > - device_writel(dev, do_percent(val, > > dev->config->boost_down_threshold), > > - ACTMON_DEV_LOWER_WMARK); > > + delta = do_percent(upper - lower, > > dev->config->boost_down_threshold); > > + device_writel(dev, lower + delta, ACTMON_DEV_LOWER_WMARK); > > } > > > > static void actmon_isr_device(struct tegra_devfreq *tegra, > > struct tegra_devfreq_device *dev) > > { > > - u32 intr_status, dev_ctrl; > > + u32 intr_status, dev_ctrl, avg_intr_mask; > > > > dev->avg_count = device_readl(dev, ACTMON_DEV_AVG_COUNT); > > - tegra_devfreq_update_avg_wmark(tegra, dev); > > - > > intr_status = device_readl(dev, ACTMON_DEV_INTR_STATUS); > > dev_ctrl = device_readl(dev, ACTMON_DEV_CTRL); > > > > + avg_intr_mask = ACTMON_DEV_INTR_AVG_BELOW_WMARK | > > + ACTMON_DEV_INTR_AVG_ABOVE_WMARK; > > + > > + if (intr_status & avg_intr_mask) > > + tegra_devfreq_update_avg_wmark(tegra, dev); > > + > > if (intr_status & ACTMON_DEV_INTR_CONSECUTIVE_UPPER) { > > /* > > * new_boost = min(old_boost * up_coef + step, > > max_freq) @@ -253,8 +390,6 @@ static void actmon_isr_device(struct > > tegra_devfreq *tegra, > > if (dev->boost_freq >= tegra->max_freq) > > dev->boost_freq = tegra->max_freq; > > - else > > - dev_ctrl |= > > ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN; } else if (intr_status > > & ACTMON_DEV_INTR_CONSECUTIVE_LOWER) { /* > > * new_boost = old_boost * down_coef > > @@ -263,63 +398,37 @@ static void actmon_isr_device(struct > > tegra_devfreq *tegra, dev->boost_freq = do_percent(dev->boost_freq, > > dev->config->boost_down_coeff); > > > > - dev_ctrl |= > > ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN; - > > if (dev->boost_freq < (ACTMON_BOOST_FREQ_STEP >> > > 1)) dev->boost_freq = 0; > > - else > > - dev_ctrl |= > > ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN; } > > > > - if (dev->config->avg_dependency_threshold) { > > - if (dev->avg_count >= > > dev->config->avg_dependency_threshold) > > - dev_ctrl |= > > ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN; > > - else if (dev->boost_freq == 0) > > - dev_ctrl &= > > ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN; > > + if (intr_status & avg_intr_mask) { > > + /* > > + * Once average watermark is hit, it means that > > the memory > > + * activity changed significantly and thus > > boosting-up shall > > + * be reset because EMC clock rate will be changed > > and > > + * boosting will restart in this case. > > + */ > > + dev->boost_freq = 0; > > } > > > > - device_writel(dev, dev_ctrl, ACTMON_DEV_CTRL); > > + /* no boosting => no need for consecutive-down interrupt */ > > + if (dev->boost_freq == 0) > > + dev_ctrl &= > > ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN; > > + device_writel(dev, dev_ctrl, ACTMON_DEV_CTRL); > > device_writel(dev, ACTMON_INTR_STATUS_CLEAR, > > ACTMON_DEV_INTR_STATUS); } > > > > -static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq > > *tegra, > > - unsigned long cpu_freq) > > -{ > > - unsigned int i; > > - struct tegra_actmon_emc_ratio *ratio = actmon_emc_ratios; > > - > > - for (i = 0; i < ARRAY_SIZE(actmon_emc_ratios); i++, > > ratio++) { > > - if (cpu_freq >= ratio->cpu_freq) { > > - if (ratio->emc_freq >= tegra->max_freq) > > - return tegra->max_freq; > > - else > > - return ratio->emc_freq; > > - } > > - } > > - > > - return 0; > > -} > > - > > -static void actmon_update_target(struct tegra_devfreq *tegra, > > - struct tegra_devfreq_device *dev) > > +static unsigned long actmon_update_target(struct tegra_devfreq > > *tegra, > > + struct > > tegra_devfreq_device *dev) { > > - unsigned long cpu_freq = 0; > > - unsigned long static_cpu_emc_freq = 0; > > - unsigned int avg_sustain_coef; > > - > > - if (dev->config->avg_dependency_threshold) { > > - cpu_freq = cpufreq_get(0); > > - static_cpu_emc_freq = > > actmon_cpu_to_emc_rate(tegra, cpu_freq); > > - } > > + unsigned long target_freq; > > > > - dev->target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD; > > - avg_sustain_coef = 100 * 100 / > > dev->config->boost_up_threshold; > > - dev->target_freq = do_percent(dev->target_freq, > > avg_sustain_coef); > > - dev->target_freq += dev->boost_freq; > > + target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD + > > dev->boost_freq; > > + target_freq = tegra_actmon_account_cpu_freq(tegra, dev, > > target_freq); > > - if (dev->avg_count >= > > dev->config->avg_dependency_threshold) > > - dev->target_freq = max(dev->target_freq, > > static_cpu_emc_freq); > > + return target_freq; > > } > > > > static irqreturn_t actmon_thread_isr(int irq, void *data) > > @@ -351,8 +460,8 @@ static int tegra_actmon_rate_notify_cb(struct > > notifier_block *nb, unsigned long action, void *ptr) > > { > > struct clk_notifier_data *data = ptr; > > - struct tegra_devfreq *tegra; > > struct tegra_devfreq_device *dev; > > + struct tegra_devfreq *tegra; > > unsigned int i; > > > > if (action != POST_RATE_CHANGE) > > @@ -360,12 +469,28 @@ static int tegra_actmon_rate_notify_cb(struct > > notifier_block *nb, > > tegra = container_of(nb, struct tegra_devfreq, > > rate_change_nb); > > - tegra->cur_freq = data->new_rate / KHZ; > > - > > + /* > > + * EMC rate could change due to three reasons: > > + * > > + * 1. Average watermark hit > > + * 2. Boosting overflow > > + * 3. CPU freq change > > + * > > + * Once rate is changed, the consecutive watermarks need > > to be > > + * updated in order for boosting to work properly and to > > avoid > > + * unnecessary interrupts. Note that the consecutive range > > is set for > > + * all of devices using the same rate, hence if CPU is > > doing much > > + * less than the other memory clients, then its upper > > watermark will > > + * be very high in comparison to the actual activity > > (lower watermark) > > + * and thus unnecessary upper-interrupts will be > > suppressed. > > + * > > + * The average watermarks also should be updated because > > of 3. > > + */ > > for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) { > > dev = &tegra->devices[i]; > > > > - tegra_devfreq_update_wmark(tegra, dev); > > + tegra_devfreq_update_avg_wmark(tegra, dev); > > + tegra_devfreq_update_wmark(tegra, dev, > > data->new_rate); } > > > > return NOTIFY_OK; > > @@ -374,15 +499,14 @@ static int tegra_actmon_rate_notify_cb(struct > > notifier_block *nb, static void > > tegra_actmon_configure_device(struct tegra_devfreq *tegra, struct > > tegra_devfreq_device *dev) { > > - u32 val = 0; > > - > > - dev->target_freq = tegra->cur_freq; > > + u32 val = 0, target_freq; > > > > - dev->avg_count = tegra->cur_freq * ACTMON_SAMPLING_PERIOD; > > + target_freq = clk_get_rate(tegra->emc_clock) / KHZ; > > + dev->avg_count = target_freq * ACTMON_SAMPLING_PERIOD; > > device_writel(dev, dev->avg_count, ACTMON_DEV_INIT_AVG); > > > > tegra_devfreq_update_avg_wmark(tegra, dev); > > - tegra_devfreq_update_wmark(tegra, dev); > > + tegra_devfreq_update_wmark(tegra, dev, target_freq); > > > > device_writel(dev, ACTMON_COUNT_WEIGHT, > > ACTMON_DEV_COUNT_WEIGHT); device_writel(dev, > > ACTMON_INTR_STATUS_CLEAR, ACTMON_DEV_INTR_STATUS); @@ -469,13 > > +593,13 @@ static int tegra_devfreq_get_dev_status(struct device > > *dev, struct tegra_devfreq_device *actmon_dev; unsigned long > > cur_freq; > > - cur_freq = READ_ONCE(tegra->cur_freq); > > + cur_freq = clk_get_rate(tegra->emc_clock); > > > > /* To be used by the tegra governor */ > > stat->private_data = tegra; > > > > /* The below are to be used by the other governors */ > > - stat->current_frequency = cur_freq * KHZ; > > + stat->current_frequency = cur_freq; > > > > actmon_dev = &tegra->devices[MCALL]; > > > > @@ -486,7 +610,7 @@ static int tegra_devfreq_get_dev_status(struct > > device *dev, stat->busy_time *= 100 / BUS_SATURATION_RATIO; > > > > /* Number of cycles in a sampling period */ > > - stat->total_time = ACTMON_SAMPLING_PERIOD * cur_freq; > > + stat->total_time = cur_freq / KHZ * ACTMON_SAMPLING_PERIOD; > > > > stat->busy_time = min(stat->busy_time, stat->total_time); > > > > @@ -505,6 +629,7 @@ static int tegra_governor_get_target(struct > > devfreq *devfreq, struct devfreq_dev_status *stat; > > struct tegra_devfreq *tegra; > > struct tegra_devfreq_device *dev; > > + unsigned long dev_target_freq; > > unsigned long target_freq = 0; > > unsigned int i; > > int err; > > @@ -520,9 +645,9 @@ static int tegra_governor_get_target(struct > > devfreq *devfreq, for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) { > > dev = &tegra->devices[i]; > > > > - actmon_update_target(tegra, dev); > > + dev_target_freq = actmon_update_target(tegra, dev); > > > > - target_freq = max(target_freq, dev->target_freq); > > + target_freq = max(target_freq, dev_target_freq); > > } > > > > *freq = target_freq * KHZ; > > @@ -642,7 +767,6 @@ static int tegra_devfreq_probe(struct > > platform_device *pdev) return rate; > > } > > > > - tegra->cur_freq = clk_get_rate(tegra->emc_clock) / KHZ; > > tegra->max_freq = rate / KHZ; > > > > for (i = 0; i < ARRAY_SIZE(actmon_device_configs); i++) { > > @@ -671,7 +795,8 @@ static int tegra_devfreq_probe(struct > > platform_device *pdev) platform_set_drvdata(pdev, tegra); > > > > tegra->rate_change_nb.notifier_call = > > tegra_actmon_rate_notify_cb; > > - err = clk_notifier_register(tegra->emc_clock, > > &tegra->rate_change_nb); > > + err = clk_notifier_register(tegra->emc_clock, > > + &tegra->rate_change_nb); > > if (err) { > > dev_err(&pdev->dev, > > "Failed to register rate change > > notifier\n"); > > > Maybe, it is possible to merge patch4/patch19/patch20 to one patch. All these three patches are completely separate changes, thus they should be kept separate.
