Date: Sun, 13 Aug 2017 16:54:37 +0200 (CEST)
From: Julia Lawall <julia.lawall@lip6.fr>
To: ruscur@russell.cc, 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
Subject: qustion about eeh_add_virt_device
Message-ID: <alpine.DEB.2.20.1708131648480.13565@hadrien>
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Hello,

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?

thanks,
julia