Re: [PATCH 1/2, v2] PM / Runtime: Rework the "runtime idle" helper routine

From: Lan Tianyu
Date: Tue Jun 04 2013 - 03:15:17 EST


2013/6/3 Rafael J. Wysocki <rjw@xxxxxxx>:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> The "runtime idle" helper routine, rpm_idle(), currently ignores
> return values from .runtime_idle() callbacks executed by it.
> However, it turns out that many subsystems use
> pm_generic_runtime_idle() which checks the return value of the
> driver's callback and executes pm_runtime_suspend() for the device
> unless that value is not 0. If that logic is moved to rpm_idle()
> instead, pm_generic_runtime_idle() can be dropped and its users
> will not need any .runtime_idle() callbacks any more.
>
> Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
> routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
> ata_port_runtime_idle(), respectively, as well as a few drivers'
> ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
> been returned by the .runtime_idle() callback executed by it.
>
> To reduce overall code bloat, make the changes described above.
>
Usb runtime pm works normally with this patch.
Tested-by: Lan Tianyu <tianyu.lan@xxxxxxxxx>

> Tested-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Tested-by: Kevin Hilman <khilman@xxxxxxxxxx>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> Acked-by: Kevin Hilman <khilman@xxxxxxxxxx>
> Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> ---
> Documentation/power/runtime_pm.txt | 5 -----
> arch/arm/mach-omap2/omap_device.c | 7 +------
> drivers/acpi/device_pm.c | 1 -
> drivers/amba/bus.c | 2 +-
> drivers/ata/libata-core.c | 2 +-
> drivers/base/platform.c | 1 -
> drivers/base/power/domain.c | 1 -
> drivers/base/power/generic_ops.c | 23 -----------------------
> drivers/base/power/runtime.c | 12 +++++-------
> drivers/dma/intel_mid_dma.c | 2 +-
> drivers/gpio/gpio-langwell.c | 6 +-----
> drivers/i2c/i2c-core.c | 2 +-
> drivers/mfd/ab8500-gpadc.c | 8 +-------
> drivers/mmc/core/bus.c | 2 +-
> drivers/mmc/core/sdio_bus.c | 2 +-
> drivers/pci/pci-driver.c | 14 +++++---------
> drivers/scsi/scsi_pm.c | 11 +++--------
> drivers/sh/pm_runtime.c | 2 +-
> drivers/spi/spi.c | 2 +-
> drivers/tty/serial/mfd.c | 9 ++-------
> drivers/usb/core/driver.c | 3 ++-
> drivers/usb/core/port.c | 1 -
> include/linux/pm_runtime.h | 2 --
> 23 files changed, 28 insertions(+), 92 deletions(-)
>
> Index: linux-pm/drivers/base/power/runtime.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/runtime.c
> +++ linux-pm/drivers/base/power/runtime.c
> @@ -293,11 +293,8 @@ static int rpm_idle(struct device *dev,
> /* Pending requests need to be canceled. */
> dev->power.request = RPM_REQ_NONE;
>
> - if (dev->power.no_callbacks) {
> - /* Assume ->runtime_idle() callback would have suspended. */
> - retval = rpm_suspend(dev, rpmflags);
> + if (dev->power.no_callbacks)
> goto out;
> - }
>
> /* Carry out an asynchronous or a synchronous idle notification. */
> if (rpmflags & RPM_ASYNC) {
> @@ -306,7 +303,8 @@ static int rpm_idle(struct device *dev,
> dev->power.request_pending = true;
> queue_work(pm_wq, &dev->power.work);
> }
> - goto out;
> + trace_rpm_return_int(dev, _THIS_IP_, 0);
> + return 0;
> }
>
> dev->power.idle_notification = true;
> @@ -326,14 +324,14 @@ static int rpm_idle(struct device *dev,
> callback = dev->driver->pm->runtime_idle;
>
> if (callback)
> - __rpm_callback(callback, dev);
> + retval = __rpm_callback(callback, dev);
>
> dev->power.idle_notification = false;
> wake_up_all(&dev->power.wait_queue);
>
> out:
> trace_rpm_return_int(dev, _THIS_IP_, retval);
> - return retval;
> + return retval ? retval : rpm_suspend(dev, rpmflags);
> }
>
> /**
> Index: linux-pm/drivers/base/power/generic_ops.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/generic_ops.c
> +++ linux-pm/drivers/base/power/generic_ops.c
> @@ -12,29 +12,6 @@
>
> #ifdef CONFIG_PM_RUNTIME
> /**
> - * pm_generic_runtime_idle - Generic runtime idle callback for subsystems.
> - * @dev: Device to handle.
> - *
> - * If PM operations are defined for the @dev's driver and they include
> - * ->runtime_idle(), execute it and return its error code, if nonzero.
> - * Otherwise, execute pm_runtime_suspend() for the device and return 0.
> - */
> -int pm_generic_runtime_idle(struct device *dev)
> -{
> - const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
> -
> - if (pm && pm->runtime_idle) {
> - int ret = pm->runtime_idle(dev);
> - if (ret)
> - return ret;
> - }
> -
> - pm_runtime_suspend(dev);
> - return 0;
> -}
> -EXPORT_SYMBOL_GPL(pm_generic_runtime_idle);
> -
> -/**
> * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems.
> * @dev: Device to suspend.
> *
> Index: linux-pm/include/linux/pm_runtime.h
> ===================================================================
> --- linux-pm.orig/include/linux/pm_runtime.h
> +++ linux-pm/include/linux/pm_runtime.h
> @@ -37,7 +37,6 @@ extern void pm_runtime_enable(struct dev
> extern void __pm_runtime_disable(struct device *dev, bool check_resume);
> extern void pm_runtime_allow(struct device *dev);
> extern void pm_runtime_forbid(struct device *dev);
> -extern int pm_generic_runtime_idle(struct device *dev);
> extern int pm_generic_runtime_suspend(struct device *dev);
> extern int pm_generic_runtime_resume(struct device *dev);
> extern void pm_runtime_no_callbacks(struct device *dev);
> @@ -143,7 +142,6 @@ static inline bool pm_runtime_active(str
> static inline bool pm_runtime_status_suspended(struct device *dev) { return false; }
> static inline bool pm_runtime_enabled(struct device *dev) { return false; }
>
> -static inline int pm_generic_runtime_idle(struct device *dev) { return 0; }
> static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; }
> static inline int pm_generic_runtime_resume(struct device *dev) { return 0; }
> static inline void pm_runtime_no_callbacks(struct device *dev) {}
> Index: linux-pm/arch/arm/mach-omap2/omap_device.c
> ===================================================================
> --- linux-pm.orig/arch/arm/mach-omap2/omap_device.c
> +++ linux-pm/arch/arm/mach-omap2/omap_device.c
> @@ -591,11 +591,6 @@ static int _od_runtime_suspend(struct de
> return ret;
> }
>
> -static int _od_runtime_idle(struct device *dev)
> -{
> - return pm_generic_runtime_idle(dev);
> -}
> -
> static int _od_runtime_resume(struct device *dev)
> {
> struct platform_device *pdev = to_platform_device(dev);
> @@ -653,7 +648,7 @@ static int _od_resume_noirq(struct devic
> struct dev_pm_domain omap_device_pm_domain = {
> .ops = {
> SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
> - _od_runtime_idle)
> + NULL)
> USE_PLATFORM_PM_SLEEP_OPS
> .suspend_noirq = _od_suspend_noirq,
> .resume_noirq = _od_resume_noirq,
> Index: linux-pm/drivers/acpi/device_pm.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/device_pm.c
> +++ linux-pm/drivers/acpi/device_pm.c
> @@ -886,7 +886,6 @@ static struct dev_pm_domain acpi_general
> #ifdef CONFIG_PM_RUNTIME
> .runtime_suspend = acpi_subsys_runtime_suspend,
> .runtime_resume = acpi_subsys_runtime_resume,
> - .runtime_idle = pm_generic_runtime_idle,
> #endif
> #ifdef CONFIG_PM_SLEEP
> .prepare = acpi_subsys_prepare,
> Index: linux-pm/drivers/amba/bus.c
> ===================================================================
> --- linux-pm.orig/drivers/amba/bus.c
> +++ linux-pm/drivers/amba/bus.c
> @@ -284,7 +284,7 @@ static const struct dev_pm_ops amba_pm =
> SET_RUNTIME_PM_OPS(
> amba_pm_runtime_suspend,
> amba_pm_runtime_resume,
> - pm_generic_runtime_idle
> + NULL
> )
> };
>
> Index: linux-pm/drivers/base/power/domain.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/domain.c
> +++ linux-pm/drivers/base/power/domain.c
> @@ -2143,7 +2143,6 @@ void pm_genpd_init(struct generic_pm_dom
> genpd->max_off_time_changed = true;
> genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
> genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
> - genpd->domain.ops.runtime_idle = pm_generic_runtime_idle;
> genpd->domain.ops.prepare = pm_genpd_prepare;
> genpd->domain.ops.suspend = pm_genpd_suspend;
> genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
> Index: linux-pm/drivers/base/platform.c
> ===================================================================
> --- linux-pm.orig/drivers/base/platform.c
> +++ linux-pm/drivers/base/platform.c
> @@ -888,7 +888,6 @@ int platform_pm_restore(struct device *d
> static const struct dev_pm_ops platform_dev_pm_ops = {
> .runtime_suspend = pm_generic_runtime_suspend,
> .runtime_resume = pm_generic_runtime_resume,
> - .runtime_idle = pm_generic_runtime_idle,
> USE_PLATFORM_PM_SLEEP_OPS
> };
>
> Index: linux-pm/drivers/i2c/i2c-core.c
> ===================================================================
> --- linux-pm.orig/drivers/i2c/i2c-core.c
> +++ linux-pm/drivers/i2c/i2c-core.c
> @@ -435,7 +435,7 @@ static const struct dev_pm_ops i2c_devic
> SET_RUNTIME_PM_OPS(
> pm_generic_runtime_suspend,
> pm_generic_runtime_resume,
> - pm_generic_runtime_idle
> + NULL
> )
> };
>
> Index: linux-pm/drivers/mmc/core/sdio_bus.c
> ===================================================================
> --- linux-pm.orig/drivers/mmc/core/sdio_bus.c
> +++ linux-pm/drivers/mmc/core/sdio_bus.c
> @@ -211,7 +211,7 @@ static const struct dev_pm_ops sdio_bus_
> SET_RUNTIME_PM_OPS(
> pm_generic_runtime_suspend,
> pm_generic_runtime_resume,
> - pm_generic_runtime_idle
> + NULL
> )
> };
>
> Index: linux-pm/drivers/spi/spi.c
> ===================================================================
> --- linux-pm.orig/drivers/spi/spi.c
> +++ linux-pm/drivers/spi/spi.c
> @@ -223,7 +223,7 @@ static const struct dev_pm_ops spi_pm =
> SET_RUNTIME_PM_OPS(
> pm_generic_runtime_suspend,
> pm_generic_runtime_resume,
> - pm_generic_runtime_idle
> + NULL
> )
> };
>
> Index: linux-pm/drivers/usb/core/port.c
> ===================================================================
> --- linux-pm.orig/drivers/usb/core/port.c
> +++ linux-pm/drivers/usb/core/port.c
> @@ -141,7 +141,6 @@ static const struct dev_pm_ops usb_port_
> #ifdef CONFIG_PM_RUNTIME
> .runtime_suspend = usb_port_runtime_suspend,
> .runtime_resume = usb_port_runtime_resume,
> - .runtime_idle = pm_generic_runtime_idle,
> #endif
> };
>
> Index: linux-pm/Documentation/power/runtime_pm.txt
> ===================================================================
> --- linux-pm.orig/Documentation/power/runtime_pm.txt
> +++ linux-pm/Documentation/power/runtime_pm.txt
> @@ -660,11 +660,6 @@ Subsystems may wish to conserve code spa
> management callbacks provided by the PM core, defined in
> driver/base/power/generic_ops.c:
>
> - int pm_generic_runtime_idle(struct device *dev);
> - - invoke the ->runtime_idle() callback provided by the driver of this
> - device, if defined, and call pm_runtime_suspend() for this device if the
> - return value is 0 or the callback is not defined
> -
> int pm_generic_runtime_suspend(struct device *dev);
> - invoke the ->runtime_suspend() callback provided by the driver of this
> device and return its result, or return -EINVAL if not defined
> Index: linux-pm/drivers/usb/core/driver.c
> ===================================================================
> --- linux-pm.orig/drivers/usb/core/driver.c
> +++ linux-pm/drivers/usb/core/driver.c
> @@ -1765,7 +1765,8 @@ int usb_runtime_idle(struct device *dev)
> */
> if (autosuspend_check(udev) == 0)
> pm_runtime_autosuspend(dev);
> - return 0;
> + /* Tell the core not to suspend it, though. */
> + return -EBUSY;
> }
>
> int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
> Index: linux-pm/drivers/pci/pci-driver.c
> ===================================================================
> --- linux-pm.orig/drivers/pci/pci-driver.c
> +++ linux-pm/drivers/pci/pci-driver.c
> @@ -1050,26 +1050,22 @@ static int pci_pm_runtime_idle(struct de
> {
> struct pci_dev *pci_dev = to_pci_dev(dev);
> const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
> + int ret = 0;
>
> /*
> * If pci_dev->driver is not set (unbound), the device should
> * always remain in D0 regardless of the runtime PM status
> */
> if (!pci_dev->driver)
> - goto out;
> + return 0;
>
> if (!pm)
> return -ENOSYS;
>
> - if (pm->runtime_idle) {
> - int ret = pm->runtime_idle(dev);
> - if (ret)
> - return ret;
> - }
> + if (pm->runtime_idle)
> + ret = pm->runtime_idle(dev);
>
> -out:
> - pm_runtime_suspend(dev);
> - return 0;
> + return ret;
> }
>
> #else /* !CONFIG_PM_RUNTIME */
> Index: linux-pm/drivers/ata/libata-core.c
> ===================================================================
> --- linux-pm.orig/drivers/ata/libata-core.c
> +++ linux-pm/drivers/ata/libata-core.c
> @@ -5430,7 +5430,7 @@ static int ata_port_runtime_idle(struct
> return -EBUSY;
> }
>
> - return pm_runtime_suspend(dev);
> + return 0;
> }
>
> static int ata_port_runtime_suspend(struct device *dev)
> Index: linux-pm/drivers/dma/intel_mid_dma.c
> ===================================================================
> --- linux-pm.orig/drivers/dma/intel_mid_dma.c
> +++ linux-pm/drivers/dma/intel_mid_dma.c
> @@ -1405,7 +1405,7 @@ static int dma_runtime_idle(struct devic
> return -EAGAIN;
> }
>
> - return pm_schedule_suspend(dev, 0);
> + return 0;
> }
>
> /******************************************************************************
> Index: linux-pm/drivers/gpio/gpio-langwell.c
> ===================================================================
> --- linux-pm.orig/drivers/gpio/gpio-langwell.c
> +++ linux-pm/drivers/gpio/gpio-langwell.c
> @@ -305,11 +305,7 @@ static const struct irq_domain_ops lnw_g
>
> static int lnw_gpio_runtime_idle(struct device *dev)
> {
> - int err = pm_schedule_suspend(dev, 500);
> -
> - if (!err)
> - return 0;
> -
> + pm_schedule_suspend(dev, 500);
> return -EBUSY;
> }
>
> Index: linux-pm/drivers/mfd/ab8500-gpadc.c
> ===================================================================
> --- linux-pm.orig/drivers/mfd/ab8500-gpadc.c
> +++ linux-pm/drivers/mfd/ab8500-gpadc.c
> @@ -886,12 +886,6 @@ static int ab8500_gpadc_runtime_resume(s
> return ret;
> }
>
> -static int ab8500_gpadc_runtime_idle(struct device *dev)
> -{
> - pm_runtime_suspend(dev);
> - return 0;
> -}
> -
> static int ab8500_gpadc_suspend(struct device *dev)
> {
> struct ab8500_gpadc *gpadc = dev_get_drvdata(dev);
> @@ -1039,7 +1033,7 @@ static int ab8500_gpadc_remove(struct pl
> static const struct dev_pm_ops ab8500_gpadc_pm_ops = {
> SET_RUNTIME_PM_OPS(ab8500_gpadc_runtime_suspend,
> ab8500_gpadc_runtime_resume,
> - ab8500_gpadc_runtime_idle)
> + NULL)
> SET_SYSTEM_SLEEP_PM_OPS(ab8500_gpadc_suspend,
> ab8500_gpadc_resume)
>
> Index: linux-pm/drivers/mmc/core/bus.c
> ===================================================================
> --- linux-pm.orig/drivers/mmc/core/bus.c
> +++ linux-pm/drivers/mmc/core/bus.c
> @@ -164,7 +164,7 @@ static int mmc_runtime_resume(struct dev
>
> static int mmc_runtime_idle(struct device *dev)
> {
> - return pm_runtime_suspend(dev);
> + return 0;
> }
>
> #endif /* !CONFIG_PM_RUNTIME */
> Index: linux-pm/drivers/scsi/scsi_pm.c
> ===================================================================
> --- linux-pm.orig/drivers/scsi/scsi_pm.c
> +++ linux-pm/drivers/scsi/scsi_pm.c
> @@ -229,8 +229,6 @@ static int scsi_runtime_resume(struct de
>
> static int scsi_runtime_idle(struct device *dev)
> {
> - int err;
> -
> dev_dbg(dev, "scsi_runtime_idle\n");
>
> /* Insert hooks here for targets, hosts, and transport classes */
> @@ -240,14 +238,11 @@ static int scsi_runtime_idle(struct devi
>
> if (sdev->request_queue->dev) {
> pm_runtime_mark_last_busy(dev);
> - err = pm_runtime_autosuspend(dev);
> - } else {
> - err = pm_runtime_suspend(dev);
> + pm_runtime_autosuspend(dev);
> + return -EBUSY;
> }
> - } else {
> - err = pm_runtime_suspend(dev);
> }
> - return err;
> + return 0;
> }
>
> int scsi_autopm_get_device(struct scsi_device *sdev)
> Index: linux-pm/drivers/sh/pm_runtime.c
> ===================================================================
> --- linux-pm.orig/drivers/sh/pm_runtime.c
> +++ linux-pm/drivers/sh/pm_runtime.c
> @@ -25,7 +25,7 @@
> static int default_platform_runtime_idle(struct device *dev)
> {
> /* suspend synchronously to disable clocks immediately */
> - return pm_runtime_suspend(dev);
> + return 0;
> }
>
> static struct dev_pm_domain default_pm_domain = {
> Index: linux-pm/drivers/tty/serial/mfd.c
> ===================================================================
> --- linux-pm.orig/drivers/tty/serial/mfd.c
> +++ linux-pm/drivers/tty/serial/mfd.c
> @@ -1248,13 +1248,8 @@ static int serial_hsu_resume(struct pci_
> #ifdef CONFIG_PM_RUNTIME
> static int serial_hsu_runtime_idle(struct device *dev)
> {
> - int err;
> -
> - err = pm_schedule_suspend(dev, 500);
> - if (err)
> - return -EBUSY;
> -
> - return 0;
> + pm_schedule_suspend(dev, 500);
> + return -EBUSY;
> }
>
> static int serial_hsu_runtime_suspend(struct device *dev)
>
> --
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--
Best regards
Tianyu Lan
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