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    SubjectRe: [PATCH 00/15] trivial: Drop unlikely before IS_ERR(_OR_NULL)
    On 31-07-15, 11:41, Vlastimil Babka wrote:
    > [+CC Steven Rostedt]
    >
    > Any idea what the compiler does in the case of
    > "if (likely(IS_ERR(...)))"? There are apparently such cases in the source.
    >
    > does the "likely" somehow override the "unlikely" of IS_ERR, or is
    > the resulting code a mess?

    Good point. While fixing all the sites, I saw some code like that. Then before
    posting the series, I tried to look at what compilers do to such codes and they
    generated exactly same code for:

    likely(unlikely(x)) and unlikely(x).

    So, either those call sites should drop the likely bits or we supply them with
    another raw version of the macro :)

    Or if my tests were wrong, then please lemme know.

    --
    viresh


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