Re: [PATCH 1/5] PM: Make the initcall_debug style timing forsuspend/resume complete

From: Alan Stern
Date: Mon Dec 21 2009 - 16:15:57 EST


On Mon, 21 Dec 2009, Rafael J. Wysocki wrote:

> From: Rafael J. Wysocki <rjw@xxxxxxx>
>
> Commit f2511774863487e61b56a97da07ebf8dd61d7836
> (PM: Add initcall_debug style timing for suspend/resume) introduced
> basic timing instrumentation, needed for a scritps/bootgraph.pl
> equivalent or humans, but it missed the fact that bus types and
> device classes which haven't been switched to using struct dev_pm_ops
> objects yet need special handling. As a result, the suspend/resume
> timing information is only available for devices whose bus types or
> device classes use struct dev_pm_ops objects, so the majority of
> devices is not covered.
>
> Fix this by adding basic suspend/resume timing instrumentation for
> devices whose bus types and device classes still don't use struct
> dev_pm_ops objects for power management. To reduce code duplication
> move the timing code to helper functions.

A minor complaint...

> +/**
> * device_resume - Execute "resume" callbacks for given device.
> * @dev: Device to handle.
> * @state: PM transition of the system being carried out.
> @@ -427,7 +465,7 @@ static int device_resume(struct device *
> error = pm_op(dev, dev->bus->pm, state);
> } else if (dev->bus->resume) {
> pm_dev_dbg(dev, state, "legacy ");
> - error = dev->bus->resume(dev);
> + error = legacy_resume(dev, dev->bus->resume);
> }
> if (error)
> goto End;
> @@ -448,7 +486,7 @@ static int device_resume(struct device *
> error = pm_op(dev, dev->class->pm, state);
> } else if (dev->class->resume) {
> pm_dev_dbg(dev, state, "legacy class ");
> - error = dev->class->resume(dev);
> + error = legacy_resume(dev, dev->class->resume);
> }
> }

If none of the method callbacks are non-NULL, this won't print
anything. The same is true for device_suspend().

Now maybe you don't _want_ to print anything in that case, but for
debugging purposes it could be useful.

Alan Stern

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