lkml.org 
[lkml]   [2004]   [Nov]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH] [CPU-HOTPLUG] convert cpucontrol to be a rwsem
    From
    Date
    On Mon, 2004-11-01 at 13:04 -0500, Lee Revell wrote:
    > On Mon, 2004-11-01 at 07:00 -0700, Zwane Mwaikambo wrote:
    > > Agreed it makes a lot more sense, i think there could be some places where
    > > we use preempt_disable to protect against cpu offline which could
    > > converted, but that can come later.
    > >
    >
    > You know I picked up Robert Love's book the other day and was surprised
    > to read we are not supposed to be using preempt_disable, there is a
    > per_cpu interface for exactly this kind of thing. Which is currently
    > recommended?

    get_cpu() both ensures that this CPU won't go down, and ensures we won't
    get scheduled off it. It returns the current processor ID, as well.
    put_cpu() puts the CPU back.

    In my experience it's usually clearer than preempt_disable().

    Cheers,
    Rusty.
    --
    A bad analogy is like a leaky screwdriver -- Richard Braakman

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 14:07    [W:0.027 / U:117.184 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site