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    SubjectRe: [PATCH v3 00/27] kill devm_ioremap_nocache
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    Le 23/12/2017 à 16:57, Guenter Roeck a écrit :
    > On 12/23/2017 05:48 AM, Greg KH wrote:
    >> On Sat, Dec 23, 2017 at 06:55:25PM +0800, Yisheng Xie wrote:
    >>> Hi all,
    >>>
    >>> When I tried to use devm_ioremap function and review related code, I
    >>> found
    >>> devm_ioremap and devm_ioremap_nocache is almost the same with each
    >>> other,
    >>> except one use ioremap while the other use ioremap_nocache.
    >>
    >> For all arches?  Really?  Look at MIPS, and x86, they have different
    >> functions.
    >>
    >
    > Both mips and x86 end up mapping the same function, but other arches don't.
    > mn10300 is one where ioremap and ioremap_nocache are definitely different.

    alpha: identical
    arc: identical
    arm: identical
    arm64: identical
    cris: different <==
    frv: identical
    hexagone: identical
    ia64: different <==
    m32r: identical
    m68k: identical
    metag: identical
    microblaze: identical
    mips: identical
    mn10300: different <==
    nios: identical
    openrisc: different <==
    parisc: identical
    riscv: identical
    s390: identical
    sh: identical
    sparc: identical
    tile: identical
    um: rely on asm/generic
    unicore32: identical
    x86: identical
    asm/generic (no mmu): identical

    So 4 among all arches seems to have ioremap() and ioremap_nocache()
    being different.

    Could we have a define set by the 4 arches on which ioremap() and
    ioremap_nocache() are different, something like
    HAVE_DIFFERENT_IOREMAP_NOCACHE ?

    Christophe

    >
    > Guenter
    >
    >>> While ioremap's
    >>> default function is ioremap_nocache, so devm_ioremap_nocache also
    >>> have the
    >>> same function with devm_ioremap, which can just be killed to reduce
    >>> the size
    >>> of devres.o(from 20304 bytes to 18992 bytes in my compile environment).
    >>>
    >>> I have posted two versions, which use macro instead of function for
    >>> devm_ioremap_nocache[1] or devm_ioremap[2]. And Greg suggest me to kill
    >>> devm_ioremap_nocache for no need to keep a macro around for the
    >>> duplicate
    >>> thing. So here comes v3 and please help to review.
    >>
    >> I don't think this can be done, what am I missing?  These functions are
    >> not identical, sorry for missing that before.
    >>
    >> thanks,
    >>
    >> greg k-h
    >>
    >
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