From: Sakari Ailus Date: Mon, 16 Jun 2025 06:12:08 +0000 (+0300) Subject: PM: runtime: Mark last busy stamp in pm_runtime_put_autosuspend() X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b3db492e8335417dfd66c1fa2ea08e1d2f7b6736;p=thirdparty%2Fkernel%2Fstable.git PM: runtime: Mark last busy stamp in pm_runtime_put_autosuspend() Set device's last busy timestamp to current time in pm_runtime_put_autosuspend(). Callers wishing not to do that will need to use __pm_runtime_put_autosuspend(). Signed-off-by: Sakari Ailus Reviewed-by: Laurent Pinchart Link: https://patch.msgid.link/20250616061212.2286741-3-sakari.ailus@linux.intel.com Signed-off-by: Rafael J. Wysocki --- diff --git a/Documentation/power/runtime_pm.rst b/Documentation/power/runtime_pm.rst index 63344bea83936..e7bbdc66d64cc 100644 --- a/Documentation/power/runtime_pm.rst +++ b/Documentation/power/runtime_pm.rst @@ -411,8 +411,9 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: pm_request_idle(dev) and return its result `int pm_runtime_put_autosuspend(struct device *dev);` - - does the same as __pm_runtime_put_autosuspend() for now, but in the - future, will also call pm_runtime_mark_last_busy() as well, DO NOT USE! + - set the power.last_busy field to the current time and decrement the + device's usage counter; if the result is 0 then run + pm_request_autosuspend(dev) and return its result `int __pm_runtime_put_autosuspend(struct device *dev);` - decrement the device's usage counter; if the result is 0 then run @@ -870,11 +871,9 @@ device is automatically suspended (the subsystem or driver still has to call the appropriate PM routines); rather it means that runtime suspends will automatically be delayed until the desired period of inactivity has elapsed. -Inactivity is determined based on the power.last_busy field. Drivers should -call pm_runtime_mark_last_busy() to update this field after carrying out I/O, -typically just before calling __pm_runtime_put_autosuspend(). The desired -length of the inactivity period is a matter of policy. Subsystems can set this -length initially by calling pm_runtime_set_autosuspend_delay(), but after device +Inactivity is determined based on the power.last_busy field. The desired length +of the inactivity period is a matter of policy. Subsystems can set this length +initially by calling pm_runtime_set_autosuspend_delay(), but after device registration the length should be controlled by user space, using the /sys/devices/.../power/autosuspend_delay_ms attribute. @@ -885,7 +884,7 @@ instead of the non-autosuspend counterparts:: Instead of: pm_runtime_suspend use: pm_runtime_autosuspend; Instead of: pm_schedule_suspend use: pm_request_autosuspend; - Instead of: pm_runtime_put use: __pm_runtime_put_autosuspend; + Instead of: pm_runtime_put use: pm_runtime_put_autosuspend; Instead of: pm_runtime_put_sync use: pm_runtime_put_sync_autosuspend. Drivers may also continue to use the non-autosuspend helper functions; they @@ -922,12 +921,10 @@ Here is a schematic pseudo-code example:: foo_io_completion(struct foo_priv *foo, void *req) { lock(&foo->private_lock); - if (--foo->num_pending_requests == 0) { - pm_runtime_mark_last_busy(&foo->dev); - __pm_runtime_put_autosuspend(&foo->dev); - } else { + if (--foo->num_pending_requests == 0) + pm_runtime_put_autosuspend(&foo->dev); + else foo_process_next_request(foo); - } unlock(&foo->private_lock); /* Send req result back to the user ... */ } diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index 9dd2e4031a27b..14ca7be96686c 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -568,11 +568,13 @@ static inline int __pm_runtime_put_autosuspend(struct device *dev) } /** - * pm_runtime_put_autosuspend - Drop device usage counter and queue autosuspend if 0. + * pm_runtime_put_autosuspend - Update the last access time of a device, drop + * its usage counter and queue autosuspend if the usage counter becomes 0. * @dev: Target device. * - * Decrement the runtime PM usage counter of @dev and if it turns out to be - * equal to 0, queue up a work item for @dev like in pm_request_autosuspend(). + * Update the last access time of @dev, decrement runtime PM usage counter of + * @dev and if it turns out to be equal to 0, queue up a work item for @dev like + * in pm_request_autosuspend(). * * Return: * * 0: Success. @@ -587,8 +589,8 @@ static inline int __pm_runtime_put_autosuspend(struct device *dev) */ static inline int pm_runtime_put_autosuspend(struct device *dev) { - return __pm_runtime_suspend(dev, - RPM_GET_PUT | RPM_ASYNC | RPM_AUTO); + pm_runtime_mark_last_busy(dev); + return __pm_runtime_put_autosuspend(dev); } /**