Re: [PATCH v2] power: new trace event to print device suspend andresume time

From: Joe Perches
Date: Wed Jul 17 2013 - 12:08:52 EST


On Wed, 2013-07-17 at 09:57 -0600, Shuah Khan wrote:
> A new trace event is added to pm events to print time it takes to suspend and
> resume a device. It generates trace message that includes device, driver,
> parent information in addition to the type of pm ops invoked as well as the
> pm event and error status from the pm ops. Example trace below:
>
> bash-2484 [001] .... 907.330148: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=freeze ops=class usecs=0 err=0
>
> bash-2484 [001] .... 909.906743: device_pm_report_time: backlight acpi_video0 parent=0000:00:02.0 state=restore ops=class usecs=0 err=0

Hi again Shuah.

A few things:

> diff --git a/include/trace/events/power.h b/include/trace/events/power.h
[]
> + TP_printk("%s %s parent=%s state=%s ops=%s usecs=%lld err=%d\n",

As I wrote before, do not end a TP_printk with "\n",

All TP_printks are self-contained and are not possible
to use a thing like pr_cont so no newline is ever used.

Use:

TP_printk("%s %s parent=%s state=%s ops=%s usecs=%lld err=%d",

Given the data is in nsecs, why use usecs for the time?
I think full resolution would be better.

Why are there two spaces after "ops=class"? One would be more normal.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/