[lkml]   [1998]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: Today Linus redesigns the networking driver interface (was Re: tulip driver in ...)
    On Tue, 22 Sep 1998 17:27:36 +1000, 
    Richard Gooch <> wrote:
    >So a heuristic to avoid BH processing isn't really worthwhile, I now
    >think, nor is a return flag from interrupt handlers saying "please
    >don't process BH's now", since the (bh_active & bh_mask) test is good
    >The simple rule: "if you haven't registered/marked active a BH, then
    >you aren't going to trigger BH processing, so don't worry about it"
    >seems like the right thing.

    Something that has been puzzling me about all of this selective do or
    don't mark_bh(). If there is data to be processed then the BH must be
    run eventually. When does the interrupt handler finally decide to
    mark_bh()? The obvious way is on a later interrupt but what happens if
    no more interrupts arrive? Extremely unlikely but possible.

    The only other way to mark_bh() is something external to the interrupt
    handler, say a timer. But that just complicates the code - is it worth
    it? Does it really cost that much to run the BH mask?

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:44    [W:0.018 / U:17.872 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site