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    SubjectRe: MD-RAID: Use seq_putc() in three status functions?
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    On 10/17/2016 06:08 PM, SF Markus Elfring wrote:
    >>> * Would you really like to know under which circumstances data processing
    >>> will be faster for a single character instead of using a string pointer
    >>> and corresponding two characters?
    >>>
    >> It's not a problem of the interface, it's a problem of the resulting code
    >> (ie assembler output).
    >
    > How do you think about to discuss concrete generated code any further?
    >
    Sure. Show me the generated code and point out where the benefits are.

    >> We can discuss all we like, if the compiler decides to throw in
    >> an optimisation none of the arguments even apply.
    >
    > Would it make sense to clarify assembler output with optimisation switched off?
    >
    > Do you eventually care for code from non-optimising compilers?
    >
    No. This is the linux kernel. There is a very, _very_ limited benefit of
    trying to use a non-standard compiler.

    >
    >>> * Will it occasionally be useful to avoid the storage for another string literal?
    >>>
    >> Occasionally: yes.
    >> In this particular case: hardly.
    >
    > I am curious when such a software design aspect can become more relevant.
    > Would it be nice to get rid of three questionable string terminators (null bytes)
    > for example?
    >
    Again, all this does it trying to out-guess what the compiler might be
    doing during compilation. For which the easiest method is checking.
    So back to the original task for you: Show me in the generated output
    where the benefits are.

    Cheers,

    Hannes
    --
    Dr. Hannes Reinecke zSeries & Storage
    hare@suse.de +49 911 74053 688
    SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
    GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)

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