[lkml]   [2012]   [Jan]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: smp: Start up non-boot CPUs asynchronously

    * Arjan van de Ven <> wrote:

    > On Tue, 31 Jan 2012 13:52:32 +0100
    > Ingo Molnar <> wrote:
    > >
    > > The real fix would be to make the init code depend less on each
    > > other, i.e. have less hotplug lock dependencies. Or, if it's
    > > such a hot lock for a good reason, why does spinning on it slow
    > > down the boot process? It really shouldnt.
    > by inspection, anything that calls
    > get_online_cpus()/put_online_cpus() will block while a CPU is
    > coming up. This is used in things like kmem_cache_create()...
    > which is used about everywhere. (there's various other
    > places... more or less it's a requirement for using the
    > for_each_online_cpu() api correctly)

    Still magic delays are not acceptable - we want to face any
    remaining performance problems head on, we want to understand
    and fix them correctly.



     \ /
      Last update: 2012-01-31 15:33    [W:0.022 / U:0.360 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site