Re: [PATCH 03/11] PM QoS: support the dynamic devices insertion and removal

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Rafael,

2011/7/2 Rafael J. Wysocki <rjw@xxxxxxx>:
> Hi,
>
> On Thursday, June 30, 2011, jean.pihet@xxxxxxxxxxxxxx wrote:
>> From: Jean Pihet <j-pihet@xxxxxx>
>>
>> The devices wake-up latency constraints class of PM QoS is
>> storing the constraints list using the device pm_info struct.
>>
>> This patch adds the init and de-init of the per-device constraints
>> list in order to support the dynamic insertion and removal
>> of the devices in the system.
>>
>> Signed-off-by: Jean Pihet <j-pihet@xxxxxx>
>
> The number of times this patch special cases PM_QOS_DEV_WAKEUP_LATENCY with
> respect to the other PM QoS classes indicates a design issue, which kind of
> corresponds with my comments on [3/11].
Do you mean 02/11? Indeed the special cases changes are introduced by
02/11. Re-designing 02/11 will solve those special cases issues.

Thanks,
Jean

>
> Thanks,
> Rafael
>
>
>> ---
>>  drivers/base/power/main.c     |    8 +++--
>>  include/linux/pm.h            |    1 +
>>  include/linux/pm_qos_params.h |    2 +
>>  kernel/pm_qos_params.c        |   70 ++++++++++++++++++++++++++++++++--------
>>  4 files changed, 64 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
>> index b1fd96b..51f5526 100644
>> --- a/drivers/base/power/main.c
>> +++ b/drivers/base/power/main.c
>> @@ -27,6 +27,7 @@
>>  #include <linux/sched.h>
>>  #include <linux/async.h>
>>  #include <linux/suspend.h>
>> +#include <linux/pm_qos_params.h>
>>
>>  #include "../base.h"
>>  #include "power.h"
>> @@ -96,8 +97,8 @@ void device_pm_add(struct device *dev)
>>                       dev_name(dev->parent));
>>       list_add_tail(&dev->power.entry, &dpm_list);
>>       mutex_unlock(&dpm_list_mtx);
>> -     /* ToDo: call PM QoS to init the per-device wakeup latency constraints */
>> -     plist_head_init(&dev->power.wakeup_lat_plist_head, &dev->power.lock);
>> +     /* Call PM QoS to init the per-device wakeup latency constraints */
>> +     pm_qos_dev_wakeup_lat_init(dev);
>>  }
>>
>>  /**
>> @@ -108,7 +109,8 @@ void device_pm_remove(struct device *dev)
>>  {
>>       pr_debug("PM: Removing info for %s:%s\n",
>>                dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
>> -     /* ToDo: call PM QoS to de-init the per-device wakeup latency constraints */
>> +     /* Call PM QoS to de-init the per-device wakeup latency constraints */
>> +     pm_qos_dev_wakeup_lat_deinit(dev);
>>       complete_all(&dev->power.completion);
>>       mutex_lock(&dpm_list_mtx);
>>       list_del_init(&dev->power.entry);
>> diff --git a/include/linux/pm.h b/include/linux/pm.h
>> index 35fe682..d9b6092 100644
>> --- a/include/linux/pm.h
>> +++ b/include/linux/pm.h
>> @@ -464,6 +464,7 @@ struct dev_pm_info {
>>       void                    *subsys_data;  /* Owned by the subsystem. */
>>  #endif
>>       struct plist_head       wakeup_lat_plist_head;
>> +     int                     wakeup_lat_init;
>>  };
>>
>>  extern void update_pm_runtime_accounting(struct device *dev);
>> diff --git a/include/linux/pm_qos_params.h b/include/linux/pm_qos_params.h
>> index e6e16cb..5b6707a 100644
>> --- a/include/linux/pm_qos_params.h
>> +++ b/include/linux/pm_qos_params.h
>> @@ -45,4 +45,6 @@ int pm_qos_add_notifier(int class, struct notifier_block *notifier);
>>  int pm_qos_remove_notifier(int class, struct notifier_block *notifier);
>>  int pm_qos_request_active(struct pm_qos_request_list *req);
>>
>> +void pm_qos_dev_wakeup_lat_init(struct device *dev);
>> +void pm_qos_dev_wakeup_lat_deinit(struct device *dev);
>>  #endif
>> diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
>> index d61c8e5..6f25ccb 100644
>> --- a/kernel/pm_qos_params.c
>> +++ b/kernel/pm_qos_params.c
>> @@ -275,11 +275,21 @@ void pm_qos_add_request(struct pm_qos_request_list *pm_qos_req,
>>       struct pm_qos_object *o =  pm_qos_array[pm_qos_params->class];
>>       int new_value;
>>
>> -     if ((pm_qos_params->class != PM_QOS_DEV_WAKEUP_LATENCY) &&
>> -         (pm_qos_request_active(pm_qos_req))) {
>> -             WARN(1, KERN_ERR "pm_qos_add_request() called for already "
>> -                  "added request\n");
>> -             return;
>> +     if (pm_qos_params->class == PM_QOS_DEV_WAKEUP_LATENCY) {
>> +             if (!pm_qos_params->dev) {
>> +                     WARN(1, KERN_ERR "pm_qos_add_request() called for "
>> +                             "invalid device\n");
>> +                     return;
>> +             }
>> +             /* Silently return if the device is being released */
>> +             if (!pm_qos_params->dev->power.wakeup_lat_init)
>> +                     return;
>> +     } else {
>> +             if (pm_qos_request_active(pm_qos_req)) {
>> +                     WARN(1, KERN_ERR "pm_qos_add_request() called for "
>> +                             "already added request\n");
>> +                     return;
>> +             }
>>       }
>>
>>       if (pm_qos_params->value == PM_QOS_DEFAULT_VALUE)
>> @@ -312,11 +322,16 @@ void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req,
>>       if (!pm_qos_req) /*guard against callers passing in null */
>>               return;
>>
>> -     if ((pm_qos_req->class != PM_QOS_DEV_WAKEUP_LATENCY) &&
>> -         (!pm_qos_request_active(pm_qos_req))) {
>> -             WARN(1, KERN_ERR "pm_qos_update_request() called for unknown "
>> -                  "object\n");
>> -             return;
>> +     if (pm_qos_req->class == PM_QOS_DEV_WAKEUP_LATENCY) {
>> +             /* Silently return if the device is being released */
>> +             if (!pm_qos_req->dev->power.wakeup_lat_init)
>> +                     return;
>> +     } else {
>> +             if (!pm_qos_request_active(pm_qos_req)) {
>> +                     WARN(1, KERN_ERR "pm_qos_update_request() called "
>> +                             "for unknown object\n");
>> +                     return;
>> +             }
>>       }
>>
>>       if (new_value == PM_QOS_DEFAULT_VALUE)
>> @@ -343,11 +358,16 @@ void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req)
>>               return;
>>               /* silent return to keep pcm code cleaner */
>>
>> -     if ((pm_qos_req->class != PM_QOS_DEV_WAKEUP_LATENCY) &&
>> -         (!pm_qos_request_active(pm_qos_req))) {
>> -             WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown "
>> -                  "object\n");
>> +     if (pm_qos_req->class == PM_QOS_DEV_WAKEUP_LATENCY) {
>> +             /* Silently return if the device is being released */
>> +             if (!pm_qos_req->dev->power.wakeup_lat_init)
>> +                     return;
>> +     } else {
>> +             if (!pm_qos_request_active(pm_qos_req)) {
>> +                     WARN(1, KERN_ERR "pm_qos_remove_request() called "
>> +                             "for unknown object\n");
>>               return;
>> +             }
>>       }
>>
>>       update_target(pm_qos_req, 1, PM_QOS_DEFAULT_VALUE);
>> @@ -393,6 +413,28 @@ int pm_qos_remove_notifier(int class, struct notifier_block *notifier)
>>  }
>>  EXPORT_SYMBOL_GPL(pm_qos_remove_notifier);
>>
>> +/* Called from the device PM subsystem at device init */
>> +void pm_qos_dev_wakeup_lat_init(struct device *dev)
>> +{
>> +     plist_head_init(&dev->power.wakeup_lat_plist_head, &dev->power.lock);
>> +     dev->power.wakeup_lat_init = 1;
>> +}
>> +
>> +/* Called from the device PM subsystem at device release */
>> +void pm_qos_dev_wakeup_lat_deinit(struct device *dev)
>> +{
>> +     struct pm_qos_request_list *req, *tmp;
>> +
>> +     dev->power.wakeup_lat_init = 0;
>> +
>> +     /* Flush the constraints list for the device */
>> +     plist_for_each_entry_safe(req, tmp,
>> +                               &dev->power.wakeup_lat_plist_head,
>> +                               list)
>> +             update_target(req, 1, PM_QOS_DEFAULT_VALUE);
>> +     plist_head_init(&dev->power.wakeup_lat_plist_head, &dev->power.lock);
>> +}
>> +
>>  static int pm_qos_power_open(struct inode *inode, struct file *filp)
>>  {
>>       struct pm_qos_parameters pm_qos_params;
>>
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux