Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754124Ab2JJDda (ORCPT ); Tue, 9 Oct 2012 23:33:30 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:51938 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752619Ab2JJDd0 (ORCPT ); Tue, 9 Oct 2012 23:33:26 -0400 Date: Tue, 9 Oct 2012 20:33:23 -0700 From: mark gross To: "Rafael J. Wysocki" Cc: Linux PM list , ACPI Devel Mailing List , Alan Stern , Huang Ying , Sarah Sharp , Lan Tianyu , Aaron Lu , Jean Pihet , linux-pci@vger.kernel.org, Greg Kroah-Hartman , mark gross , LKML Subject: Re: [PATCH 5/7] PM / QoS: Make it possible to expose PM QoS device flags to user space Message-ID: <20121010033323.GC21067@MGROSS-X220VM> Reply-To: markgross@thegnar.org References: <201209282351.10663.rjw@sisk.pl> <1413438.1MkXj8vjQK@vostro.rjw.lan> <5925717.MuPWJfgSgk@vostro.rjw.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5925717.MuPWJfgSgk@vostro.rjw.lan> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 17984 Lines: 542 On Mon, Oct 08, 2012 at 10:07:58AM +0200, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > Define two device PM QoS flags, PM_QOS_FLAG_NO_POWER_OFF > and PM_QOS_FLAG_REMOTE_WAKEUP, and introduce routines > dev_pm_qos_expose_flags() and dev_pm_qos_hide_flags() allowing the > caller to expose those two flags to user space or to hide them > from it, respectively. > > After the flags have been exposed, user space will see two > additional sysfs attributes, pm_qos_no_power_off and > pm_qos_remote_wakeup, under the device's /sys/devices/.../power/ > directory. Then, writing 1 to one of them will update the > PM QoS flags request owned by user space so that the corresponding > flag is requested to be set. In turn, writing 0 to one of them > will cause the corresponding flag in the user space's request to > be cleared (however, the owners of the other PM QoS flags requests > for the same device may still request the flag to be set and it > may be effectively set even if user space doesn't request that). > > Signed-off-by: Rafael J. Wysocki > Reviewed-by: Jean Pihet > --- > Documentation/ABI/testing/sysfs-devices-power | 31 ++++ > drivers/base/power/power.h | 6 > drivers/base/power/qos.c | 167 ++++++++++++++++++++------ > drivers/base/power/sysfs.c | 95 +++++++++++++- > include/linux/pm.h | 1 > include/linux/pm_qos.h | 26 ++++ > 6 files changed, 278 insertions(+), 48 deletions(-) > > Index: linux/include/linux/pm_qos.h > =================================================================== > --- linux.orig/include/linux/pm_qos.h > +++ linux/include/linux/pm_qos.h > @@ -34,6 +34,9 @@ enum pm_qos_flags_status { > #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0 > #define PM_QOS_DEV_LAT_DEFAULT_VALUE 0 > > +#define PM_QOS_FLAG_NO_POWER_OFF (1 << 0) > +#define PM_QOS_FLAG_REMOTE_WAKEUP (1 << 1) > + > struct pm_qos_request { > struct plist_node node; > int pm_qos_class; > @@ -86,6 +89,8 @@ struct pm_qos_flags { > struct dev_pm_qos { > struct pm_qos_constraints latency; > struct pm_qos_flags flags; > + struct dev_pm_qos_request *latency_req; > + struct dev_pm_qos_request *flags_req; I think I'm getting it now. if someday we have per device throughput you would have us add a pm_qos_constraints throughput; and a dev_pm_qos_request *throughput_req; > }; > > /* Action requested to pm_qos_update_target */ > @@ -187,10 +192,31 @@ static inline int dev_pm_qos_add_ancesto > #ifdef CONFIG_PM_RUNTIME > int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value); > void dev_pm_qos_hide_latency_limit(struct device *dev); > +int dev_pm_qos_expose_flags(struct device *dev, s32 value); > +void dev_pm_qos_hide_flags(struct device *dev); > +int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set); > + > +static inline s32 dev_pm_qos_requested_latency(struct device *dev) > +{ > + return dev->power.qos->latency_req->data.pnode.prio; > +} > + > +static inline s32 dev_pm_qos_requested_flags(struct device *dev) > +{ > + return dev->power.qos->flags_req->data.flr.flags; > +} > #else > static inline int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) > { return 0; } > static inline void dev_pm_qos_hide_latency_limit(struct device *dev) {} > +static inline int dev_pm_qos_expose_flags(struct device *dev, s32 value) > + { return 0; } > +static inline void dev_pm_qos_hide_flags(struct device *dev) {} > +static inline int dev_pm_qos_update_flags(struct device *dev, s32 m, bool set) > + { return 0; } > + > +static inline s32 dev_pm_qos_requested_latency(struct device *dev) { return 0; } > +static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; } > #endif > > #endif > Index: linux/include/linux/pm.h > =================================================================== > --- linux.orig/include/linux/pm.h > +++ linux/include/linux/pm.h > @@ -548,7 +548,6 @@ struct dev_pm_info { > unsigned long active_jiffies; > unsigned long suspended_jiffies; > unsigned long accounting_timestamp; > - struct dev_pm_qos_request *pq_req; > #endif > struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */ > struct dev_pm_qos *qos; > Index: linux/drivers/base/power/qos.c > =================================================================== > --- linux.orig/drivers/base/power/qos.c > +++ linux/drivers/base/power/qos.c > @@ -40,6 +40,7 @@ > #include > #include > #include > +#include > > #include "power.h" > > @@ -322,6 +323,36 @@ int dev_pm_qos_add_request(struct device > EXPORT_SYMBOL_GPL(dev_pm_qos_add_request); > > /** > + * __dev_pm_qos_update_request - Modify an existing device PM QoS request. > + * @req : PM QoS request to modify. > + * @new_value: New value to request. > + */ > +int __dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value) > +{ > + s32 curr_value; > + int ret = 0; > + > + if (!req->dev->power.qos) > + return -ENODEV; > + > + switch(req->type) { > + case DEV_PM_QOS_LATENCY: > + curr_value = req->data.pnode.prio; > + break; > + case DEV_PM_QOS_FLAGS: > + curr_value = req->data.flr.flags; > + break; > + default: > + return -EINVAL; > + } > + > + if (curr_value != new_value) > + ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value); > + > + return ret; > +} > + > +/** > * dev_pm_qos_update_request - modifies an existing qos request > * @req : handle to list element holding a dev_pm_qos request to use > * @new_value: defines the qos request > @@ -336,11 +367,9 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_add_request > * -EINVAL in case of wrong parameters, -ENODEV if the device has been > * removed from the system > */ > -int dev_pm_qos_update_request(struct dev_pm_qos_request *req, > - s32 new_value) > +int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value) > { > - s32 curr_value; > - int ret = 0; > + int ret; > > if (!req) /*guard against callers passing in null */ > return -EINVAL; > @@ -350,29 +379,9 @@ int dev_pm_qos_update_request(struct dev > return -EINVAL; > > mutex_lock(&dev_pm_qos_mtx); > - > - if (!req->dev->power.qos) { > - ret = -ENODEV; > - goto out; > - } > - > - switch(req->type) { > - case DEV_PM_QOS_LATENCY: > - curr_value = req->data.pnode.prio; > - break; > - case DEV_PM_QOS_FLAGS: > - curr_value = req->data.flr.flags; > - break; > - default: > - ret = -EINVAL; > - goto out; > - } > - > - if (curr_value != new_value) > - ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value); > - > - out: > + __dev_pm_qos_update_request(req, new_value); > mutex_unlock(&dev_pm_qos_mtx); > + > return ret; > } > EXPORT_SYMBOL_GPL(dev_pm_qos_update_request); > @@ -533,10 +542,19 @@ int dev_pm_qos_add_ancestor_request(stru > EXPORT_SYMBOL_GPL(dev_pm_qos_add_ancestor_request); > > #ifdef CONFIG_PM_RUNTIME > -static void __dev_pm_qos_drop_user_request(struct device *dev) > +static void __dev_pm_qos_drop_user_request(struct device *dev, > + enum dev_pm_qos_req_type type) > { > - dev_pm_qos_remove_request(dev->power.pq_req); > - dev->power.pq_req = NULL; > + switch(type) { > + case DEV_PM_QOS_LATENCY: > + dev_pm_qos_remove_request(dev->power.qos->latency_req); > + dev->power.qos->latency_req = NULL; > + break; > + case DEV_PM_QOS_FLAGS: > + dev_pm_qos_remove_request(dev->power.qos->flags_req); > + dev->power.qos->flags_req = NULL; > + break; > + } > } > > /** > @@ -552,7 +570,7 @@ int dev_pm_qos_expose_latency_limit(stru > if (!device_is_registered(dev) || value < 0) > return -EINVAL; > > - if (dev->power.pq_req) > + if (dev->power.qos && dev->power.qos->latency_req) > return -EEXIST; > > req = kzalloc(sizeof(*req), GFP_KERNEL); > @@ -563,10 +581,10 @@ int dev_pm_qos_expose_latency_limit(stru > if (ret < 0) > return ret; > > - dev->power.pq_req = req; > - ret = pm_qos_sysfs_add(dev); > + dev->power.qos->latency_req = req; > + ret = pm_qos_sysfs_add_latency(dev); > if (ret) > - __dev_pm_qos_drop_user_request(dev); > + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY); > > return ret; > } > @@ -578,10 +596,87 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_expose_late > */ > void dev_pm_qos_hide_latency_limit(struct device *dev) > { > - if (dev->power.pq_req) { > - pm_qos_sysfs_remove(dev); > - __dev_pm_qos_drop_user_request(dev); > + if (dev->power.qos && dev->power.qos->latency_req) { > + pm_qos_sysfs_remove_latency(dev); > + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY); > } > } > EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_limit); > + > +/** > + * dev_pm_qos_expose_flags - Expose PM QoS flags of a device to user space. > + * @dev: Device whose PM QoS flags are to be exposed to user space. > + * @val: Initial values of the flags. > + */ > +int dev_pm_qos_expose_flags(struct device *dev, s32 val) > +{ > + struct dev_pm_qos_request *req; > + int ret; > + > + if (!device_is_registered(dev)) > + return -EINVAL; > + > + if (dev->power.qos && dev->power.qos->flags_req) > + return -EEXIST; > + > + req = kzalloc(sizeof(*req), GFP_KERNEL); > + if (!req) > + return -ENOMEM; > + > + ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_FLAGS, val); > + if (ret < 0) > + return ret; > + > + dev->power.qos->flags_req = req; > + ret = pm_qos_sysfs_add_flags(dev); > + if (ret) > + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(dev_pm_qos_expose_flags); > + > +/** > + * dev_pm_qos_hide_flags - Hide PM QoS flags of a device from user space. > + * @dev: Device whose PM QoS flags are to be hidden from user space. > + */ > +void dev_pm_qos_hide_flags(struct device *dev) > +{ > + if (dev->power.qos && dev->power.qos->flags_req) { > + pm_qos_sysfs_remove_flags(dev); > + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); > + } > +} > +EXPORT_SYMBOL_GPL(dev_pm_qos_hide_flags); > + > +/** > + * dev_pm_qos_update_flags - Update PM QoS flags request owned by user space. > + * @dev: Device to update the PM QoS flags request for. > + * @mask: Flags to set/clear. > + * @set: Whether to set or clear the flags (true means set). > + */ > +int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set) > +{ > + s32 value; > + int ret; > + > + if (!dev->power.qos || !dev->power.qos->flags_req) > + return -EINVAL; > + > + pm_runtime_get_sync(dev); > + mutex_lock(&dev_pm_qos_mtx); > + > + value = dev_pm_qos_requested_flags(dev); > + if (set) > + value |= mask; > + else > + value &= ~mask; > + > + ret = __dev_pm_qos_update_request(dev->power.qos->flags_req, value); > + > + mutex_unlock(&dev_pm_qos_mtx); > + pm_runtime_put(dev); > + > + return ret; > +} > #endif /* CONFIG_PM_RUNTIME */ > Index: linux/drivers/base/power/power.h > =================================================================== > --- linux.orig/drivers/base/power/power.h > +++ linux/drivers/base/power/power.h > @@ -93,8 +93,10 @@ extern void dpm_sysfs_remove(struct devi > extern void rpm_sysfs_remove(struct device *dev); > extern int wakeup_sysfs_add(struct device *dev); > extern void wakeup_sysfs_remove(struct device *dev); > -extern int pm_qos_sysfs_add(struct device *dev); > -extern void pm_qos_sysfs_remove(struct device *dev); > +extern int pm_qos_sysfs_add_latency(struct device *dev); > +extern void pm_qos_sysfs_remove_latency(struct device *dev); > +extern int pm_qos_sysfs_add_flags(struct device *dev); > +extern void pm_qos_sysfs_remove_flags(struct device *dev); > > #else /* CONFIG_PM */ > > Index: linux/drivers/base/power/sysfs.c > =================================================================== > --- linux.orig/drivers/base/power/sysfs.c > +++ linux/drivers/base/power/sysfs.c > @@ -221,7 +221,7 @@ static DEVICE_ATTR(autosuspend_delay_ms, > static ssize_t pm_qos_latency_show(struct device *dev, > struct device_attribute *attr, char *buf) > { > - return sprintf(buf, "%d\n", dev->power.pq_req->data.pnode.prio); > + return sprintf(buf, "%d\n", dev_pm_qos_requested_latency(dev)); > } > > static ssize_t pm_qos_latency_store(struct device *dev, > @@ -237,12 +237,67 @@ static ssize_t pm_qos_latency_store(stru > if (value < 0) > return -EINVAL; > > - ret = dev_pm_qos_update_request(dev->power.pq_req, value); > + ret = dev_pm_qos_update_request(dev->power.qos->latency_req, value); > return ret < 0 ? ret : n; > } > > static DEVICE_ATTR(pm_qos_resume_latency_us, 0644, > pm_qos_latency_show, pm_qos_latency_store); > + > +static ssize_t pm_qos_no_power_off_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev) > + & PM_QOS_FLAG_NO_POWER_OFF)); > +} > + > +static ssize_t pm_qos_no_power_off_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t n) > +{ > + int ret; > + > + if (kstrtoint(buf, 0, &ret)) > + return -EINVAL; > + > + if (ret != 0 && ret != 1) > + return -EINVAL; > + > + ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret); > + return ret < 0 ? ret : n; > +} > + > +static DEVICE_ATTR(pm_qos_no_power_off, 0644, > + pm_qos_no_power_off_show, pm_qos_no_power_off_store); > + > +static ssize_t pm_qos_remote_wakeup_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev) > + & PM_QOS_FLAG_REMOTE_WAKEUP)); > +} > + > +static ssize_t pm_qos_remote_wakeup_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t n) > +{ > + s32 value; > + int ret; > + > + if (kstrtoint(buf, 0, &ret)) > + return -EINVAL; > + > + if (ret != 0 && ret != 1) > + return -EINVAL; > + > + ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP, ret); > + return ret < 0 ? ret : n; > +} > + > +static DEVICE_ATTR(pm_qos_remote_wakeup, 0644, > + pm_qos_remote_wakeup_show, pm_qos_remote_wakeup_store); > #endif /* CONFIG_PM_RUNTIME */ > > #ifdef CONFIG_PM_SLEEP > @@ -564,15 +619,27 @@ static struct attribute_group pm_runtime > .attrs = runtime_attrs, > }; > > -static struct attribute *pm_qos_attrs[] = { > +static struct attribute *pm_qos_latency_attrs[] = { > #ifdef CONFIG_PM_RUNTIME > &dev_attr_pm_qos_resume_latency_us.attr, > #endif /* CONFIG_PM_RUNTIME */ > NULL, > }; > -static struct attribute_group pm_qos_attr_group = { > +static struct attribute_group pm_qos_latency_attr_group = { > + .name = power_group_name, > + .attrs = pm_qos_latency_attrs, > +}; > + > +static struct attribute *pm_qos_flags_attrs[] = { > +#ifdef CONFIG_PM_RUNTIME > + &dev_attr_pm_qos_no_power_off.attr, > + &dev_attr_pm_qos_remote_wakeup.attr, > +#endif /* CONFIG_PM_RUNTIME */ > + NULL, > +}; > +static struct attribute_group pm_qos_flags_attr_group = { > .name = power_group_name, > - .attrs = pm_qos_attrs, > + .attrs = pm_qos_flags_attrs, > }; > > int dpm_sysfs_add(struct device *dev) > @@ -615,14 +682,24 @@ void wakeup_sysfs_remove(struct device * > sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); > } > > -int pm_qos_sysfs_add(struct device *dev) > +int pm_qos_sysfs_add_latency(struct device *dev) > +{ > + return sysfs_merge_group(&dev->kobj, &pm_qos_latency_attr_group); > +} > + > +void pm_qos_sysfs_remove_latency(struct device *dev) > +{ > + sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_attr_group); > +} > + > +int pm_qos_sysfs_add_flags(struct device *dev) > { > - return sysfs_merge_group(&dev->kobj, &pm_qos_attr_group); > + return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group); > } > > -void pm_qos_sysfs_remove(struct device *dev) > +void pm_qos_sysfs_remove_flags(struct device *dev) > { > - sysfs_unmerge_group(&dev->kobj, &pm_qos_attr_group); > + sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group); > } > > void rpm_sysfs_remove(struct device *dev) > Index: linux/Documentation/ABI/testing/sysfs-devices-power > =================================================================== > --- linux.orig/Documentation/ABI/testing/sysfs-devices-power > +++ linux/Documentation/ABI/testing/sysfs-devices-power > @@ -204,3 +204,34 @@ Description: > > This attribute has no effect on system-wide suspend/resume and > hibernation. > + > +What: /sys/devices/.../power/pm_qos_no_power_off > +Date: September 2012 > +Contact: Rafael J. Wysocki > +Description: > + The /sys/devices/.../power/pm_qos_no_power_off attribute > + is used for manipulating the PM QoS "no power off" flag. If > + set, this flag indicates to the kernel that power should not > + be removed entirely from the device. > + > + Not all drivers support this attribute. If it isn't supported, > + it is not present. > + > + This attribute has no effect on system-wide suspend/resume and > + hibernation. > + > +What: /sys/devices/.../power/pm_qos_remote_wakeup > +Date: September 2012 > +Contact: Rafael J. Wysocki > +Description: > + The /sys/devices/.../power/pm_qos_remote_wakeup attribute > + is used for manipulating the PM QoS "remote wakeup required" > + flag. If set, this flag indicates to the kernel that the > + device is a source of user events that have to be signaled from > + its low-power states. > + > + Not all drivers support this attribute. If it isn't supported, > + it is not present. > + > + This attribute has no effect on system-wide suspend/resume and > + hibernation. > acked-by: mark gross -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/