[lkml]   [1999]   [Nov]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: linux interrupt handling problem
    >    Date:   Tue, 9 Nov 1999 16:37:32 +0000 (GMT)
    > From: Alan Cox <>
    > Add an arch specific
    > spin_lockat_cli(lock, flags, pri)
    > Smells too much like spl(), which has in the past been deemed
    > evil by the king penguin.

    He can deem what he likes evil. The plain truth is simple. MacOS can do this,
    Linux can't. It is certainly not a generic solution thats why I said it
    belongs in arch code. It is really dropping an ultra-thin RT layer on
    Linux m68k, and pretty much all of Linus "here be deadlock" and other
    comments apply.

    However if you want to do 64Kbit sync off a MacII or 38,400 async you have
    to accept that the 85x30 series devices are a real time problem.

    You don't want to pollute the main code with irq levels but you do want to
    draw a line and say "below this IPL is linux" "above this IPL its party
    time". You define all the Linux locking to work by raising to the given IPL
    not the top IPL, and you play _very_ carefully in your 'real time' IRQ


    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 13:54    [W:0.020 / U:2.508 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site