On 26.11.2019 23:01, Matthias Kaehlcke wrote:
> On Tue, Nov 26, 2019 at 05:17:13PM +0200, Leonard Crestez wrote:
>> Support for adding per-device frequency limits was removed in
>> commit 2aac8bdf7a0f ("PM: QoS: Drop frequency QoS types from device PM QoS")
>> after cpufreq switched to use a new "freq_constraints" construct.
>>
>> Restore support for per-device freq limits but base this upon
>> freq_constraints. This is primarily meant to be used by the devfreq
>> subsystem.
>>
>> This removes the "static" marking on freq_qos_apply but does not export
>> it for modules.
>>
>> Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
>> ---
>> drivers/base/power/qos.c | 73 ++++++++++++++++++++++++++++++++++++----
>> include/linux/pm_qos.h | 12 +++++++
>> kernel/power/qos.c | 4 ++-
>> 3 files changed, 82 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
>> index 350dcafd751f..8e93167f1783 100644
>> --- a/drivers/base/power/qos.c
>> +++ b/drivers/base/power/qos.c
>> @@ -113,14 +113,24 @@ s32 dev_pm_qos_read_value(struct device *dev, enum dev_pm_qos_req_type type)
>> unsigned long flags;
>> s32 ret;
>>
>> spin_lock_irqsave(&dev->power.lock, flags);
>>
>> - if (type == DEV_PM_QOS_RESUME_LATENCY) {
>> + switch (type) {
>> + case DEV_PM_QOS_RESUME_LATENCY:
>> ret = IS_ERR_OR_NULL(qos) ? PM_QOS_RESUME_LATENCY_NO_CONSTRAINT
>> : pm_qos_read_value(&qos->resume_latency);
>> - } else {
>> + break;
>> + case DEV_PM_QOS_MIN_FREQUENCY:
>> + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE
>> + : freq_qos_read_value(&qos->freq, FREQ_QOS_MIN);
>> + break;
>> + case DEV_PM_QOS_MAX_FREQUENCY:
>> + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE
>> + : freq_qos_read_value(&qos->freq, FREQ_QOS_MAX);
>> + break;
>> + default:
>> WARN_ON(1);
>> ret = 0;
>> }
>>
>> spin_unlock_irqrestore(&dev->power.lock, flags);
>> @@ -157,10 +167,14 @@ static int apply_constraint(struct dev_pm_qos_request *req,
>> if (ret) {
>> value = pm_qos_read_value(&qos->latency_tolerance);
>> req->dev->power.set_latency_tolerance(req->dev, value);
>> }
>> break;
>> + case DEV_PM_QOS_MIN_FREQUENCY:
>> + case DEV_PM_QOS_MAX_FREQUENCY:
>> + ret = freq_qos_apply(&req->data.freq, action, value);
>> + break;
>> case DEV_PM_QOS_FLAGS:
>> ret = pm_qos_update_flags(&qos->flags, &req->data.flr,
>> action, value);
>> break;
>> default:
>> @@ -207,10 +221,12 @@ static int dev_pm_qos_constraints_allocate(struct device *dev)
>> c->target_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE;
>> c->default_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE;
>> c->no_constraint_value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
>> c->type = PM_QOS_MIN;
>>
>> + freq_constraints_init(&qos->freq);
>> +
>> INIT_LIST_HEAD(&qos->flags.list);
>>
>> spin_lock_irq(&dev->power.lock);
>> dev->power.qos = qos;
>> spin_unlock_irq(&dev->power.lock);
>> @@ -267,10 +283,24 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
>> plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) {
>> apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
>> memset(req, 0, sizeof(*req));
>> }
>>
>> + c = &qos->freq.min_freq;
>> + plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) {
>> + apply_constraint(req, PM_QOS_REMOVE_REQ,
>> + PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE);
>> + memset(req, 0, sizeof(*req));
>> + }
>> +
>> + c = &qos->freq.max_freq;
>> + plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) {
>> + apply_constraint(req, PM_QOS_REMOVE_REQ,
>> + PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE);
>> + memset(req, 0, sizeof(*req));
>> + }
>> +
>
> nit: these loops look a bit redundant, might be worth to encapsulate them in a
> macro.
There are only 2 identical loops though? Other requests to be cleared
are enumerated in slightly different ways.
A pm_qos_for_each_request macro could be added but it would only be used
in a handful of places.
>> f = &qos->flags;
>> list_for_each_entry_safe(req, tmp, &f->list, data.flr.node) {
>> apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
>> memset(req, 0, sizeof(*req));
>> }
>> @@ -312,15 +342,26 @@ static int __dev_pm_qos_add_request(struct device *dev,
>> ret = -ENODEV;
>> else if (!dev->power.qos)
>> ret = dev_pm_qos_constraints_allocate(dev);
>>
>> trace_dev_pm_qos_add_request(dev_name(dev), type, value);
>> - if (!ret) {
>> - req->dev = dev;
>> - req->type = type;
>> + if (ret)
>> + return ret;
>> +
>> + req->dev = dev;
>> + req->type = type;
>> + if (req->type == DEV_PM_QOS_MIN_FREQUENCY)
>> + ret = freq_qos_add_request(&dev->power.qos->freq,
>> + &req->data.freq,
>> + FREQ_QOS_MIN, value);
>> + else if (req->type == DEV_PM_QOS_MAX_FREQUENCY)
>> + ret = freq_qos_add_request(&dev->power.qos->freq,
>> + &req->data.freq,
>> + FREQ_QOS_MAX, value);
>> + else
>> ret = apply_constraint(req, PM_QOS_ADD_REQ, value);
>> - }
>> +
>> return ret;
>> }
>>
>> /**
>> * dev_pm_qos_add_request - inserts new qos request into the list
>> @@ -380,10 +421,14 @@ static int __dev_pm_qos_update_request(struct dev_pm_qos_request *req,
>> switch(req->type) {
>> case DEV_PM_QOS_RESUME_LATENCY:
>> case DEV_PM_QOS_LATENCY_TOLERANCE:
>> curr_value = req->data.pnode.prio;
>> break;
>> + case DEV_PM_QOS_MIN_FREQUENCY:
>> + case DEV_PM_QOS_MAX_FREQUENCY:
>> + curr_value = req->data.freq.pnode.prio;
>> + break;
>> case DEV_PM_QOS_FLAGS:
>> curr_value = req->data.flr.flags;
>> break;
>> default:
>> return -EINVAL;
>> @@ -505,10 +550,18 @@ int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier,
>> switch (type) {
>> case DEV_PM_QOS_RESUME_LATENCY:
>> ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers,
>> notifier);
>> break;
>> + case DEV_PM_QOS_MIN_FREQUENCY:
>> + ret = freq_qos_add_notifier(&dev->power.qos->freq,
>> + FREQ_QOS_MIN, notifier);
>> + break;
>> + case DEV_PM_QOS_MAX_FREQUENCY:
>> + ret = freq_qos_add_notifier(&dev->power.qos->freq,
>> + FREQ_QOS_MAX, notifier);
>> + break;
>> default:
>> WARN_ON(1);
>> ret = -EINVAL;
>> }
>>
>> @@ -544,10 +597,18 @@ int dev_pm_qos_remove_notifier(struct device *dev,
>> switch (type) {
>> case DEV_PM_QOS_RESUME_LATENCY:
>> ret = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers,
>> notifier);
>> break;
>> + case DEV_PM_QOS_MIN_FREQUENCY:
>> + ret = freq_qos_remove_notifier(&dev->power.qos->freq,
>> + FREQ_QOS_MIN, notifier);
>> + break;
>> + case DEV_PM_QOS_MAX_FREQUENCY:
>> + ret = freq_qos_remove_notifier(&dev->power.qos->freq,
>> + FREQ_QOS_MAX, notifier);
>> + break;
>> default:
>> WARN_ON(1);
>> ret = -EINVAL;
>> }
>>
>> diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
>> index 678fec6da5b9..19eafca5680e 100644
>> --- a/include/linux/pm_qos.h
>> +++ b/include/linux/pm_qos.h
>> @@ -32,10 +32,12 @@ enum pm_qos_flags_status {
>> #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC)
>> #define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE PM_QOS_LATENCY_ANY
>> #define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT PM_QOS_LATENCY_ANY
>> #define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS PM_QOS_LATENCY_ANY_NS
>> #define PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE 0
>> +#define PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE 0
>> +#define PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE FREQ_QOS_MAX_DEFAULT_VALUE
>> #define PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT (-1)
>>
>> #define PM_QOS_FLAG_NO_POWER_OFF (1 << 0)
>>
>> struct pm_qos_request {
>> @@ -99,25 +101,29 @@ struct freq_qos_request {
>>
>>
>> enum dev_pm_qos_req_type {
>> DEV_PM_QOS_RESUME_LATENCY = 1,
>> DEV_PM_QOS_LATENCY_TOLERANCE,
>> + DEV_PM_QOS_MIN_FREQUENCY,
>> + DEV_PM_QOS_MAX_FREQUENCY,
>> DEV_PM_QOS_FLAGS,
>> };
>>
>> struct dev_pm_qos_request {
>> enum dev_pm_qos_req_type type;
>> union {
>> struct plist_node pnode;
>> struct pm_qos_flags_request flr;
>> + struct freq_qos_request freq;
>> } data;
>> struct device *dev;
>> };
>>
>> struct dev_pm_qos {
>> struct pm_qos_constraints resume_latency;
>> struct pm_qos_constraints latency_tolerance;
>> + struct freq_constraints freq;
>> struct pm_qos_flags flags;
>> struct dev_pm_qos_request *resume_latency_req;
>> struct dev_pm_qos_request *latency_tolerance_req;
>> struct dev_pm_qos_request *flags_req;
>> };
>> @@ -212,10 +218,14 @@ static inline s32 dev_pm_qos_read_value(struct device *dev,
>> enum dev_pm_qos_req_type type)
>> {
>> switch (type) {
>> case DEV_PM_QOS_RESUME_LATENCY:
>> return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
>> + case DEV_PM_QOS_MIN_FREQUENCY:
>> + return PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE;
>> + case DEV_PM_QOS_MAX_FREQUENCY:
>> + return PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE;
>> default:
>> WARN_ON(1);
>> return 0;
>> }
>> }
>> @@ -291,10 +301,12 @@ s32 freq_qos_read_value(struct freq_constraints *qos,
>> int freq_qos_add_request(struct freq_constraints *qos,
>> struct freq_qos_request *req,
>> enum freq_qos_req_type type, s32 value);
>> int freq_qos_update_request(struct freq_qos_request *req, s32 new_value);
>> int freq_qos_remove_request(struct freq_qos_request *req);
>> +int freq_qos_apply(struct freq_qos_request *req,
>> + enum pm_qos_req_action action, s32 value);
>>
>> int freq_qos_add_notifier(struct freq_constraints *qos,
>> enum freq_qos_req_type type,
>> struct notifier_block *notifier);
>> int freq_qos_remove_notifier(struct freq_constraints *qos,
>> diff --git a/kernel/power/qos.c b/kernel/power/qos.c
>> index a45cba7df0ae..83edf8698118 100644
>> --- a/kernel/power/qos.c
>> +++ b/kernel/power/qos.c
>> @@ -712,12 +712,14 @@ s32 freq_qos_read_value(struct freq_constraints *qos,
>> /**
>> * freq_qos_apply - Add/modify/remove frequency QoS request.
>> * @req: Constraint request to apply.
>> * @action: Action to perform (add/update/remove).
>> * @value: Value to assign to the QoS request.
>> + *
>> + * This is only meant to be called from inside pm_qos, not drivers.
>> */
>> -static int freq_qos_apply(struct freq_qos_request *req,
>> +int freq_qos_apply(struct freq_qos_request *req,
>> enum pm_qos_req_action action, s32 value)
>> {
>> int ret;
>>
>> switch(req->type) {
>
> Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> Tested-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Thanks for taking the time to look into this.
