Hi, On 3/31/21 5:03 PM, andrew-sh.cheng wrote: > On Thu, 2021-03-25 at 17:14 +0900, Chanwoo Choi wrote: >> Hi, >> >> You are missing to add these patches to linux-pm mailing list. >> Need to send them to linu-pm ML. >> >> Also, before received this series, I tried to clean-up these patches >> on testing branch[1]. So that I add my comment with my clean-up case. >> [1] https://urldefense.com/v3/__https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/log/?h=devfreq-testing-passive-gov__;!!CTRNKA9wMg0ARbw!zIrzeDp9vPnm1_SDzVPuzqdHn3zWie9DnfBXaA-j9-CSrVc6aR9_rJQQiw81_CgAPh9XRRs$ >> >> And 'Saravana Kannan <skannan@xxxxxxxxxxxxxx>' is wrong email address. >> Please update the email or drop this email. > > Hi Chanwoo, > > Thank you for the advices. > I will resend patch v9 (add to linux-pm ML), remove this patch, and note > that my patch set base on > https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/log/?h=devfreq-testing-passive-gov I has not yet test this patch[1] on devfreq-testing-passive-gov branch. So that if possible, I'd like you to test your patches with this patch[1] and then if there is no problem, could you send the next patches with patch[1]? [1]https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/commit/?h=devfreq-testing-passive-gov&id=39c80d11a8f42dd63ecea1e0df595a0ceb83b454 > > >> >> >> On 3/23/21 8:33 PM, Andrew-sh.Cheng wrote: >>> From: Saravana Kannan <skannan@xxxxxxxxxxxxxx> >>> >>> Many CPU architectures have caches that can scale independent of the >>> CPUs. Frequency scaling of the caches is necessary to make sure that the >>> cache is not a performance bottleneck that leads to poor performance and >>> power. The same idea applies for RAM/DDR. >>> >>> To achieve this, this patch adds support for cpu based scaling to the >>> passive governor. This is accomplished by taking the current frequency >>> of each CPU frequency domain and then adjust the frequency of the cache >>> (or any devfreq device) based on the frequency of the CPUs. It listens >>> to CPU frequency transition notifiers to keep itself up to date on the >>> current CPU frequency. >>> >>> To decide the frequency of the device, the governor does one of the >>> following: >>> * Derives the optimal devfreq device opp from required-opps property of >>> the parent cpu opp_table. >>> >>> * Scales the device frequency in proportion to the CPU frequency. So, if >>> the CPUs are running at their max frequency, the device runs at its >>> max frequency. If the CPUs are running at their min frequency, the >>> device runs at its min frequency. It is interpolated for frequencies >>> in between. >>> >>> Andrew-sh.Cheng change >>> dev_pm_opp_xlate_opp to dev_pm_opp_xlate_required_opp devfreq->max_freq >>> to devfreq->user_min_freq_req.data.freq.qos->min_freq.target_value >>> after kernel-5.7 >>> Don't return -EINVAL in devfreq_passive_event_handler() >>> since it doesn't handle DEVFREQ_GOV_SUSPEND DEVFREQ_GOV_RESUME cases. >>> >>> Signed-off-by: Saravana Kannan <skannan@xxxxxxxxxxxxxx> >>> [Sibi: Integrated cpu-freqmap governor into passive_governor] >>> Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx> >>> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@xxxxxxxxxxxx> >>> --- >>> drivers/devfreq/Kconfig | 2 + >>> drivers/devfreq/governor_passive.c | 329 +++++++++++++++++++++++++++++++++++-- >>> include/linux/devfreq.h | 29 +++- >>> 3 files changed, 342 insertions(+), 18 deletions(-) >>> >>> diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig >>> index 00704efe6398..f56132b0ae64 100644 >>> --- a/drivers/devfreq/Kconfig >>> +++ b/drivers/devfreq/Kconfig >>> @@ -73,6 +73,8 @@ config DEVFREQ_GOV_PASSIVE >>> device. This governor does not change the frequency by itself >>> through sysfs entries. The passive governor recommends that >>> devfreq device uses the OPP table to get the frequency/voltage. >>> + Alternatively the governor can also be chosen to scale based on >>> + the online CPUs current frequency. >>> >>> comment "DEVFREQ Drivers" >>> >>> diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c >>> index b094132bd20b..9cc57b083839 100644 >>> --- a/drivers/devfreq/governor_passive.c >>> +++ b/drivers/devfreq/governor_passive.c >>> @@ -8,11 +8,103 @@ >>> */ >>> >>> #include <linux/module.h> >>> +#include <linux/cpu.h> >>> +#include <linux/cpufreq.h> >>> +#include <linux/cpumask.h> >>> #include <linux/device.h> >>> #include <linux/devfreq.h> >>> +#include <linux/slab.h> >>> #include "governor.h" >>> >>> -static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>> +struct devfreq_cpu_state { >>> + unsigned int curr_freq; >>> + unsigned int min_freq; >>> + unsigned int max_freq; >>> + unsigned int first_cpu; >>> + struct device *cpu_dev; >>> + struct opp_table *opp_table; >>> +}; >> >> As I knew, the previous version has the description of structure >> as following: I wan to add the description like below. >> >> And if you have no any objection, I'd like you to order >> the variables as following and use 'dev' instead of 'cpu_dev' >> because this patch use the 'cpu_state->cpu_dev' at the multiple points. >> I think that 'cpu_state->dev' is better than 'cpu_state->cpu_dev'. >> Also, I prefer to use 'cur_freq' instead of 'curr_freq' >> because devfreq subsystem uses 'cur_freq' for expressing the 'current frequency'. >> >> /** >> * struct devfreq_cpu_state - Hold the per-cpu data >> * @dev: reference to cpu device. >> * @first_cpu: the cpumask of the first cpu of a policy. >> * @opp_table: reference to cpu opp table. >> * @cur_freq: the current frequency of the cpu. >> * @min_freq: the min frequency of the cpu. >> * @max_freq: the max frequency of the cpu. >> * >> * This structure stores the required cpu_data of a cpu. >> * This is auto-populated by the governor. >> */ >> struct devfreq_cpu_state { >> struct device *dev; >> unsigned int first_cpu; >> >> struct opp_table *opp_table; >> unsigned int cur_freq; >> unsigned int min_freq; >> unsigned int max_freq; >> }; >> >> >>> + >>> +static unsigned long xlate_cpufreq_to_devfreq(struct devfreq_passive_data *data, >>> + unsigned int cpu) >>> +{ >>> + unsigned int cpu_min_freq, cpu_max_freq, cpu_curr_freq_khz, cpu_percent; >>> + unsigned long dev_min_freq, dev_max_freq, dev_max_state; >>> + >>> + struct devfreq_cpu_state *cpu_state = data->cpu_state[cpu]; >>> + struct devfreq *devfreq = (struct devfreq *)data->this; >>> + unsigned long *dev_freq_table = devfreq->profile->freq_table; >>> + struct dev_pm_opp *opp = NULL, *p_opp = NULL; >>> + unsigned long cpu_curr_freq, freq; >>> + >>> + if (!cpu_state || cpu_state->first_cpu != cpu || >>> + !cpu_state->opp_table || !devfreq->opp_table) >>> + return 0; >>> + >>> + cpu_curr_freq = cpu_state->curr_freq * 1000; >>> + p_opp = devfreq_recommended_opp(cpu_state->cpu_dev, &cpu_curr_freq, 0); >>> + if (IS_ERR(p_opp)) >>> + return 0; >>> + >>> + opp = dev_pm_opp_xlate_required_opp(cpu_state->opp_table, >>> + devfreq->opp_table, p_opp); >>> + dev_pm_opp_put(p_opp); >>> + >>> + if (!IS_ERR(opp)) { >>> + freq = dev_pm_opp_get_freq(opp); >>> + dev_pm_opp_put(opp); >>> + goto out; >>> + } >>> + >>> + /* Use Interpolation if required opps is not available */ >>> + cpu_min_freq = cpu_state->min_freq; >>> + cpu_max_freq = cpu_state->max_freq; >>> + cpu_curr_freq_khz = cpu_state->curr_freq; >>> + >>> + if (dev_freq_table) { >>> + /* Get minimum frequency according to sorting order */ >>> + dev_max_state = dev_freq_table[devfreq->profile->max_state - 1]; >>> + if (dev_freq_table[0] < dev_max_state) { >>> + dev_min_freq = dev_freq_table[0]; >>> + dev_max_freq = dev_max_state; >>> + } else { >>> + dev_min_freq = dev_max_state; >>> + dev_max_freq = dev_freq_table[0]; >>> + } >>> + } else { >>> + dev_min_freq = dev_pm_qos_read_value(devfreq->dev.parent, >>> + DEV_PM_QOS_MIN_FREQUENCY); >>> + dev_max_freq = dev_pm_qos_read_value(devfreq->dev.parent, >>> + DEV_PM_QOS_MAX_FREQUENCY); >>> + >>> + if (dev_max_freq <= dev_min_freq) >>> + return 0; >>> + } >>> + cpu_percent = ((cpu_curr_freq_khz - cpu_min_freq) * 100) / cpu_max_freq - cpu_min_freq; >>> + freq = dev_min_freq + mult_frac(dev_max_freq - dev_min_freq, cpu_percent, 100); >>> + >>> +out: >>> + return freq; >>> +} >>> + >>> +static int get_target_freq_with_cpufreq(struct devfreq *devfreq, >>> + unsigned long *freq) >>> +{ >>> + struct devfreq_passive_data *p_data = >>> + (struct devfreq_passive_data *)devfreq->data; >>> + unsigned int cpu; >>> + unsigned long target_freq = 0; >>> + >>> + for_each_online_cpu(cpu) >>> + target_freq = max(target_freq, >>> + xlate_cpufreq_to_devfreq(p_data, cpu)); >>> + >>> + *freq = target_freq; >>> + >>> + return 0; >>> +} >> >> As you knew, governor_passive.c was already used >> both 'dev_pm_opp_xlate_required_opp' and 'devfreq_recommended_opp' >> to get the target from OPP. So, I wan to make the common function >> like 'get_taget_freq_by_required_opp' as following: >> If define 'get_taget_freq_by_required_opp' as following, >> it will be used for get_target_freq_with_devfreq(). >> After finisied the review of this patch, I'll send the patch[2]. >> [2] https://urldefense.com/v3/__https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/commit/?h=devfreq-testing-passive-gov&id=101c5a087586ab2b5cf3370166a7e39227ca83cf__;!!CTRNKA9wMg0ARbw!zIrzeDp9vPnm1_SDzVPuzqdHn3zWie9DnfBXaA-j9-CSrVc6aR9_rJQQiw81_CgA6mp3Yqo$ >> >> For example but this code is not tested, >> static unsigned long get_taget_freq_by_required_opp(struct device *p_dev, >> struct opp_table *p_opp_table, >> struct opp_table *opp_table, >> unsigned long freq) >> { >> struct dev_pm_opp *opp = NULL, *p_opp = NULL; >> >> if (!p_dev || !p_opp_table || !opp_table || !freq) >> return 0; >> >> p_opp = devfreq_recommended_opp(p_dev, &freq, 0); >> if (IS_ERR(p_opp)) >> return 0; >> >> opp = dev_pm_opp_xlate_required_opp(p_opp_table, opp_table, p_opp); >> dev_pm_opp_put(p_opp); >> >> if (IS_ERR(opp)) >> return 0; >> >> freq = dev_pm_opp_get_freq(opp); >> dev_pm_opp_put(opp); >> >> return freq; >> } >> >> static int get_target_freq_with_cpufreq(struct devfreq *devfreq, >> unsigned long *target_freq) >> { >> struct devfreq_passive_data *p_data = >> (struct devfreq_passive_data *)devfreq->data; >> struct devfreq_cpu_data *cpu_data; >> unsigned long cpu, cpu_cur, cpu_min, cpu_max, cpu_percent; >> unsigned long dev_min, dev_max; >> unsigned long freq = 0; >> >> for_each_online_cpu(cpu) { >> cpu_data = p_data->cpu_data[cpu]; >> if (!cpu_data || cpu_data->first_cpu != cpu) >> continue; >> >> /* Get target freq via required opps */ >> cpu_cur = cpu_data->cur_freq * HZ_PER_KHZ; >> freq = get_taget_freq_by_required_opp(cpu_data->dev, >> cpu_data->opp_table, >> devfreq->opp_table, cpu_cur); >> if (freq) { >> *target_freq = max(freq, *target_freq); >> continue; >> } >> >> /* Use Interpolation if required opps is not available */ >> devfreq_get_freq_range(devfreq, &dev_min, &dev_max); >> >> cpu_min = cpu_data->min_freq; >> cpu_max = cpu_data->max_freq; >> cpu_cur = cpu_data->cur_freq; >> >> cpu_percent = ((cpu_cur - cpu_min) * 100) / cpu_max - cpu_min; >> freq = dev_min + mult_frac(dev_max - dev_min, cpu_percent, 100); >> >> *target_freq = max(freq, *target_freq); >> } >> >> return 0; >> } >> >>> + >>> +static int get_target_freq_with_devfreq(struct devfreq *devfreq, >>> unsigned long *freq) >>> { >>> struct devfreq_passive_data *p_data >>> @@ -23,14 +115,6 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>> int i, count; >>> >>> /* >>> - * If the devfreq device with passive governor has the specific method >>> - * to determine the next frequency, should use the get_target_freq() >>> - * of struct devfreq_passive_data. >>> - */ >>> - if (p_data->get_target_freq) >>> - return p_data->get_target_freq(devfreq, freq); >>> - >>> - /* >>> * If the parent and passive devfreq device uses the OPP table, >>> * get the next frequency by using the OPP table. >>> */ >>> @@ -98,6 +182,37 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>> return 0; >>> } >>> >>> +static int devfreq_passive_get_target_freq(struct devfreq *devfreq, >>> + unsigned long *freq) >>> +{ >>> + struct devfreq_passive_data *p_data = >>> + (struct devfreq_passive_data *)devfreq->data; >>> + int ret; >>> + >>> + /* >>> + * If the devfreq device with passive governor has the specific method >>> + * to determine the next frequency, should use the get_target_freq() >>> + * of struct devfreq_passive_data. >>> + */ >>> + if (p_data->get_target_freq) >>> + return p_data->get_target_freq(devfreq, freq); >>> + >>> + switch (p_data->parent_type) { >>> + case DEVFREQ_PARENT_DEV: >>> + ret = get_target_freq_with_devfreq(devfreq, freq); >>> + break; >>> + case CPUFREQ_PARENT_DEV: >>> + ret = get_target_freq_with_cpufreq(devfreq, freq); >>> + break; >>> + default: >>> + ret = -EINVAL; >>> + dev_err(&devfreq->dev, "Invalid parent type\n"); >>> + break; >>> + } >>> + >>> + return ret; >>> +} >>> + >>> static int devfreq_passive_notifier_call(struct notifier_block *nb, >>> unsigned long event, void *ptr) >>> { >>> @@ -130,16 +245,200 @@ static int devfreq_passive_notifier_call(struct notifier_block *nb, >>> return NOTIFY_DONE; >>> } >>> >>> +static int cpufreq_passive_notifier_call(struct notifier_block *nb, >>> + unsigned long event, void *ptr) >>> +{ >>> + struct devfreq_passive_data *data = >>> + container_of(nb, struct devfreq_passive_data, nb); >>> + struct devfreq *devfreq = (struct devfreq *)data->this; >>> + struct devfreq_cpu_state *cpu_state; >>> + struct cpufreq_freqs *cpu_freq = ptr; >> >> Use 'freqs' variable name. I prefer to use the same variable name >> for both devfreq_freqs and cpufreq_freqs instance. >> >>> + unsigned int curr_freq; >> >> As I commented above, better to use 'cur_frq' instead of 'curr_freq' >> if there is no any special reason. >> >>> + int ret; >>> + >>> + if (event != CPUFREQ_POSTCHANGE || !cpu_freq || >>> + !data->cpu_state[cpu_freq->policy->cpu]) >>> + return 0; >>> + >>> + cpu_state = data->cpu_state[cpu_freq->policy->cpu]; >>> + if (cpu_state->curr_freq == cpu_freq->new) >>> + return 0; >>> + >>> + /* Backup current freq and pre-update cpu state freq*/ >> >> I think that this commnet is not critial. So, please drop this comment. >> >>> + curr_freq = cpu_state->curr_freq; >>> + cpu_state->curr_freq = cpu_freq->new; >>> + >>> + mutex_lock(&devfreq->lock); >>> + ret = update_devfreq(devfreq); >> >> I recommend to use 'devfreq_update_target' instead of 'update_devfreq' >> as following: >> devfreq_update_target(devfreq, freqs->new); >> >>> + mutex_unlock(&devfreq->lock); >>> + if (ret) { >>> + cpu_state->curr_freq = curr_freq; >>> + dev_err(&devfreq->dev, "Couldn't update the frequency.\n"); >>> + return ret; >>> + } >>> + >>> + return 0; >>> +} >>> + >>> +static int cpufreq_passive_register(struct devfreq_passive_data **p_data) >> >> In order to keep the consistent style of function name, >> please change the name as following because devfreq defines >> the function name as 'devfreq_regiter_notifier' >> - cpufreq_passive_register -> cpufreq_passive_register_notifier >> >>> +{ >>> + struct devfreq_passive_data *data = *p_data; >>> + struct devfreq *devfreq = (struct devfreq *)data->this; >>> + struct device *dev = devfreq->dev.parent; >>> + struct opp_table *opp_table = NULL; >>> + struct devfreq_cpu_state *cpu_state; >>> + struct cpufreq_policy *policy; >>> + struct device *cpu_dev; >>> + unsigned int cpu; >>> + int ret; >>> + >>> + get_online_cpus(); >>> + >>> + data->nb.notifier_call = cpufreq_passive_notifier_call; >>> + ret = cpufreq_register_notifier(&data->nb, >>> + CPUFREQ_TRANSITION_NOTIFIER); >>> + if (ret) { >>> + dev_err(dev, "Couldn't register cpufreq notifier.\n"); >>> + data->nb.notifier_call = NULL; >>> + goto out; >>> + } >>> + >>> + /* Populate devfreq_cpu_state */ >> >> Don't need this comment. Please drop it. >> >>> + for_each_online_cpu(cpu) { >>> + if (data->cpu_state[cpu]) >>> + continue; >>> + >>> + policy = cpufreq_cpu_get(cpu); >>> + if (!policy) { >>> + ret = -EINVAL; >>> + goto out; >>> + } else if (PTR_ERR(policy) == -EPROBE_DEFER) { >>> + ret = -EPROBE_DEFER; >>> + goto out; >>> + } else if (IS_ERR(policy)) { >>> + ret = PTR_ERR(policy); >>> + dev_err(dev, "Couldn't get the cpufreq_poliy.\n"); >>> + goto out; >>> + } >> >> Use dev_err_probe() funciotn to handle hte EPROBE_DEFER. >> It make code more simple. >> >>> + >>> + cpu_state = kzalloc(sizeof(*cpu_state), GFP_KERNEL); >>> + if (!cpu_state) { >>> + ret = -ENOMEM; >>> + goto out; >>> + } >>> + >>> + cpu_dev = get_cpu_device(cpu); >>> + if (!cpu_dev) { >>> + dev_err(dev, "Couldn't get cpu device.\n"); >>> + ret = -ENODEV; >>> + goto out; >>> + } >>> + >>> + opp_table = dev_pm_opp_get_opp_table(cpu_dev); >>> + if (IS_ERR(devfreq->opp_table)) { >>> + ret = PTR_ERR(opp_table); >>> + goto out; >>> + } >>> + >>> + cpu_state->cpu_dev = cpu_dev; >>> + cpu_state->opp_table = opp_table; >>> + cpu_state->first_cpu = cpumask_first(policy->related_cpus); >>> + cpu_state->curr_freq = policy->cur; >>> + cpu_state->min_freq = policy->cpuinfo.min_freq; >>> + cpu_state->max_freq = policy->cpuinfo.max_freq; >>> + data->cpu_state[cpu] = cpu_state; >>> + >>> + cpufreq_cpu_put(policy); >>> + } >>> + >>> +out: >>> + put_online_cpus(); >>> + if (ret) >>> + return ret; >>> + >>> + /* Update devfreq */ >>> + mutex_lock(&devfreq->lock); >>> + ret = update_devfreq(devfreq); >> >>> + mutex_unlock(&devfreq->lock); >>> + if (ret) >>> + dev_err(dev, "Couldn't update the frequency.\n"); >>> + >>> + return ret; >>> +} >>> + >>> +static int cpufreq_passive_unregister(struct devfreq_passive_data **p_data) >> >> As I commented above, please change the name as following: >> - cpufreq_passive_unregister -> cpufreq_passive_unregister_notifier >> >>> +{ >>> + struct devfreq_passive_data *data = *p_data; >>> + struct devfreq_cpu_state *cpu_state; >>> + int cpu; >>> + >>> + if (data->nb.notifier_call) >>> + cpufreq_unregister_notifier(&data->nb, >>> + CPUFREQ_TRANSITION_NOTIFIER); >>> + >>> + for_each_possible_cpu(cpu) { >>> + cpu_state = data->cpu_state[cpu]; >>> + if (cpu_state) { >>> + if (cpu_state->opp_table) >>> + dev_pm_opp_put_opp_table(cpu_state->opp_table); >>> + kfree(cpu_state); >>> + cpu_state = NULL; >>> + } >>> + } >>> + >>> + return 0; >>> +} >>> + >>> +int register_parent_dev_notifier(struct devfreq_passive_data **p_data) >>> +{ >>> + struct notifier_block *nb = &(*p_data)->nb; >>> + int ret = 0; >>> + >>> + switch ((*p_data)->parent_type) { >>> + case DEVFREQ_PARENT_DEV: >>> + nb->notifier_call = devfreq_passive_notifier_call; >>> + ret = devfreq_register_notifier((struct devfreq *)(*p_data)->parent, nb, >>> + DEVFREQ_TRANSITION_NOTIFIER); >>> + break; >>> + case CPUFREQ_PARENT_DEV: >>> + ret = cpufreq_passive_register(p_data); >>> + break; >>> + default: >>> + ret = -EINVAL; >>> + break; >>> + } >>> + return ret; >>> +} >>> + >>> +int unregister_parent_dev_notifier(struct devfreq_passive_data **p_data) >>> +{ >>> + int ret = 0; >>> + >>> + switch ((*p_data)->parent_type) { >>> + case DEVFREQ_PARENT_DEV: >>> + WARN_ON(devfreq_unregister_notifier((struct devfreq *)(*p_data)->parent, >>> + &(*p_data)->nb, >>> + DEVFREQ_TRANSITION_NOTIFIER)); >>> + break; >>> + case CPUFREQ_PARENT_DEV: >>> + cpufreq_passive_unregister(p_data); >>> + break; >>> + default: >>> + ret = -EINVAL; >>> + break; >>> + } >>> + return ret; >>> +} >> >> I think that you don't need to define register_parent_dev_notifier >> and unregister_parent_dev_notifier as the separate functions. >> >> Instead of the separate functions, just add the code >> into devfreq_passive_event_handler. >> >> >>> + >>> static int devfreq_passive_event_handler(struct devfreq *devfreq, >>> unsigned int event, void *data) >>> { >>> struct devfreq_passive_data *p_data >>> = (struct devfreq_passive_data *)devfreq->data; >>> struct devfreq *parent = (struct devfreq *)p_data->parent; >>> - struct notifier_block *nb = &p_data->nb; >>> int ret = 0; >>> >>> - if (!parent) >>> + if (p_data->parent_type == DEVFREQ_PARENT_DEV && !parent) >>> return -EPROBE_DEFER; >>> >>> switch (event) { >>> @@ -147,13 +446,11 @@ static int devfreq_passive_event_handler(struct devfreq *devfreq, >>> if (!p_data->this) >>> p_data->this = devfreq; >>> >>> - nb->notifier_call = devfreq_passive_notifier_call; >>> - ret = devfreq_register_notifier(parent, nb, >>> - DEVFREQ_TRANSITION_NOTIFIER); >>> + ret = register_parent_dev_notifier(&p_data); >>> break; >>> + >>> case DEVFREQ_GOV_STOP: >>> - WARN_ON(devfreq_unregister_notifier(parent, nb, >>> - DEVFREQ_TRANSITION_NOTIFIER)); >>> + ret = unregister_parent_dev_notifier(&p_data); >>> break; >>> default: >>> break; >>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h >>> index 26ea0850be9b..e0093b7c805c 100644 >>> --- a/include/linux/devfreq.h >>> +++ b/include/linux/devfreq.h >>> @@ -280,6 +280,25 @@ struct devfreq_simple_ondemand_data { >>> >>> #if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE) >>> /** >>> + * struct devfreq_cpu_state - holds the per-cpu state >>> + * @freq: the current frequency of the cpu. >>> + * @min_freq: the min frequency of the cpu. >>> + * @max_freq: the max frequency of the cpu. >>> + * @first_cpu: the cpumask of the first cpu of a policy. >>> + * @dev: reference to cpu device. >>> + * @opp_table: reference to cpu opp table. >>> + * >>> + * This structure stores the required cpu_state of a cpu. >>> + * This is auto-populated by the governor. >>> + */ >>> +struct devfreq_cpu_state; >>> + >>> +enum devfreq_parent_dev_type { >>> + DEVFREQ_PARENT_DEV, >>> + CPUFREQ_PARENT_DEV, >>> +}; >>> + >>> +/** >>> * struct devfreq_passive_data - ``void *data`` fed to struct devfreq >>> * and devfreq_add_device >>> * @parent: the devfreq instance of parent device. >>> @@ -290,13 +309,15 @@ struct devfreq_simple_ondemand_data { >>> * using governors except for passive governor. >>> * If the devfreq device has the specific method to decide >>> * the next frequency, should use this callback. >>> + * @parent_type: parent type of the device >>> * @this: the devfreq instance of own device. >>> * @nb: the notifier block for DEVFREQ_TRANSITION_NOTIFIER list >>> + * @cpu_state: the state min/max/current frequency of all online cpu's >>> * >>> * The devfreq_passive_data have to set the devfreq instance of parent >>> * device with governors except for the passive governor. But, don't need to >>> - * initialize the 'this' and 'nb' field because the devfreq core will handle >>> - * them. >>> + * initialize the 'this', 'nb' and 'cpu_state' field because the devfreq core >>> + * will handle them. >>> */ >>> struct devfreq_passive_data { >>> /* Should set the devfreq instance of parent device */ >>> @@ -305,9 +326,13 @@ struct devfreq_passive_data { >>> /* Optional callback to decide the next frequency of passvice device */ >>> int (*get_target_freq)(struct devfreq *this, unsigned long *freq); >>> >>> + /* Should set the type of parent device */ >>> + enum devfreq_parent_dev_type parent_type; >>> + >>> /* For passive governor's internal use. Don't need to set them */ >>> struct devfreq *this; >>> struct notifier_block nb; >>> + struct devfreq_cpu_state *cpu_state[NR_CPUS]; >>> }; >>> #endif >>> >>> >> > -- Best Regards, Chanwoo Choi Samsung Electronics
