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Message-ID: <1503380692.7369.0.camel@russell.cc>
Subject: Re: qustion about eeh_add_virt_device
From: Russell Currey <ruscur@russell.cc>
To: Julia Lawall <julia.lawall@lip6.fr>, benh@kernel.crashing.org,
 paulus@samba.org, mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org,
 linux-kernel@vger.kernel.org
Cc: hch@infradead.org
Date: Tue, 22 Aug 2017 15:44:52 +1000
In-Reply-To: <alpine.DEB.2.20.1708131648480.13565@hadrien>
References: <alpine.DEB.2.20.1708131648480.13565@hadrien>
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On Sun, 2017-08-13 at 16:54 +0200, Julia Lawall wrote:
> Hello,

Hello, sorry for the delayed response.

> 
> At the suggestion of Christoph Hellwig, I am working on inlining the
> functions stored in the err_handler field of a pci_driver structure into
> the pci_driver structure itself.  A number of functions in the file
> arch/powerpc/kernel/eeh_driver.c have code like:
> 
>         if (!driver->err_handler ||
>             !driver->err_handler->error_detected) {
>                 eeh_pcid_put(dev);
>                 return NULL;
>         }
> 
> This I would just convert to:
> 
>         if (!driver->error_detected) {
>                 eeh_pcid_put(dev);
>                 return NULL;
>         }
> 
> But I am not sure what is best to do about eeh_add_virt_device, which
> contains:
> 
>                 if (driver->err_handler)
> 		        return NULL;
> 
> Should I try to find a subfield of the err_handler that is guaranteed to
> be there if anything is there?  Or could the test just be dropped, leaving
> a direct return NULL?

I believe the test can be dropped.

- Russell

> 
> thanks,
> julia