lkml.org 
[lkml]   [2007]   [Jun]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: "upping" a semaphore from interrupt context?
    On Sat, 23 Jun 2007, Arnd Bergmann wrote:

    > On Saturday 23 June 2007, Robert P. J. Day wrote:
    > > On Fri, 22 Jun 2007, Arnd Bergmann wrote:
    > > >
    > > > yes, but you should not. The use of semaphores is not
    > > > recommended for new code, it should be replaced with either a
    > > > mutex or a completion.
    > >
    > > can you clarify this?  it sounds like you're saying that the
    > > current implementation of semaphores is entirely superfluous.  but
    > > surely it isn't possible to replace all semaphores with either
    > > mutexes or completions, is it?
    >
    > No, not all of them, but the vast majority. There are multiple
    > differences, the most important one being the 'counting' in
    > semaphores.

    right, that was exactly the feature i was thinking of. ok, i'm clear
    on this now -- while the *majority* of semaphores can be more properly
    replaced by mutexes or completions, there will always be a need for a
    general-purpose counting semaphore.

    rday
    --
    ========================================================================
    Robert P. J. Day
    Linux Consulting, Training and Annoying Kernel Pedantry
    Waterloo, Ontario, CANADA

    http://fsdev.net/wiki/index.php?title=Main_Page
    ========================================================================
    \
     
     \ /
      Last update: 2007-06-23 14:13    [W:0.021 / U:0.408 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site