Date: Mon, 18 Mar 2013 19:37:43 -0700
From: Greg KH <gregkh@linuxfoundation.org>
To: "Li, Fei" <fei.li@intel.com>
Cc: "rjw@sisk.pl" <rjw@sisk.pl>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "ldewangan@nvidia.com" <ldewangan@nvidia.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Liu, Chuansheng" <chuansheng.liu@intel.com>
Subject: Re: [PATCH] pm: print the name of failed suspend function for
 platform device
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On Tue, Mar 19, 2013 at 02:05:02AM +0000, Li, Fei wrote:
> > > Print more info when platform device suspend function failed.
> > > Without this patch, we can not get the real platform device suspend
> > > API info.
> > >
> > > Example without this patch:
> > > pm_op(): platform_pm_suspend+0x0/0x50 returns -11
> > > PM: Device power.0 failed to suspend: error -11
> > >
> > > And with this patch:
> > > platform_pm_suspend(): power_suspend+0x0/0x30 returns -11
> > > pm_op(): platform_pm_suspend+0x0/0x80 returns -11
> > > PM: Device power.0 failed to suspend: error -11
> > 
> > How does that help someone out?  One extra line?  What is that going to
> > allow a user to now do?
> >
> Thanks for your comments.
> 
> The intention is to print relatively complete call path for convenience of
> debugging in case of error. With this, we can know the exact name of
> the concrete failed function.

And what was the failed function here, and what would that enable you to
do?

> Besides, currently such information is printed with level KERN_ERR,
> and can be tuned through console_loglevel to avoid the possible impact
> to end user.

Huh?  End users see KERN_ERR.

> Do you think it make sense?

no.  But this is Rafael's file, so I'll defer to him.

greg k-h

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