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    SubjectRe: [PATCH 02/39] x86, PCI: have own version for pcibios_bus_to_resource
    On Wed, Feb 29, 2012 at 4:33 PM, Yinghai Lu <yinghai@kernel.org> wrote:
    > On Wed, Feb 29, 2012 at 3:20 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
    >> On Wed, Feb 29, 2012 at 4:07 PM, Yinghai Lu <yinghai@kernel.org> wrote:
    >>> x86 does not need to offset the address. So we can skip that costing offset
    >>> searching.
    >>
    >> I tried to start a discussion about this patch (and others), but I
    >> don't think you responded:
    >> http://marc.info/?l=linux-pci&m=133036414506921&w=2
    >
    > this patch does reduce some not needed ops.
    >
    > and it does not affects your effects,

    It does affect my efforts in that this patch adds back x86 complexity
    that I don't think is necessary.

    And this patch makes it so the pci_add_resource_offset() interface
    exists and appears to work on x86, but if somebody tries to use it, it
    *doesn't* work. I don't like to write code like that. I think it's
    poor style.

    > and it just make x86 not get punished.

    What punishment are you worried about? I really don't think you'll be
    able to measure any performance impact.

    I agree that the x86 code you add *is* simpler than the generic
    version. But I think the *overall* complexity is higher because now
    you have to look at two versions (generic and x86) and convince
    yourself that it's safe to use the x86 version.

    Bjorn


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