lkml.org 
[lkml]   [2007]   [May]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: 2.6.22-rc1: Broken suspend on SMP with tifm
    Date
    On Sunday, 13 May 2007 23:54, Oleg Nesterov wrote:
    > On 05/13, Rafael J. Wysocki wrote:
    > >
    > > On Sunday, 13 May 2007 23:34, Oleg Nesterov wrote:
    > > > On 05/13, Rafael J. Wysocki wrote:
    > > > >
    > > > > @@ -819,20 +843,31 @@ static int __devinit workqueue_cpu_callb
    > > > >
    > > > > +
    > > > > + case CPU_DEAD_FROZEN:
    > > > > + if (wq->freezeable) {
    > > > > + take_over_work(wq, cpu);
    > > > > + thaw_process(cwq->thread);
    > > >
    > > > Suppose that PF_NOFREEZE task T does flush_workqueue(), and CPU 1 has pending
    > > > works. T does flush_cpu_workqueue(0), CPU_DEAD_FROZEN moves works from CPU 1
    > > > to CPU 0, T does flush_cpu_workqueue(1) and finds nothing.
    > >
    > > I don't think this is possible, because we've acquired workqueue_mutex in
    > > _cpu_down().
    >
    > Yes, we did... but flush_workqueue() doesn't take it?

    I was looking at the 2.6.21 code, sorry.

    Hmm, I guess we could add an additional mutex that would only be taken in
    flush_workqueue() and in _cpu_down()/_cpu_up() via workqueue_cpu_callback()
    with CPU_LOCK_ACQUIRE?

    It doesn't seem to be a good idea to run flush_workqueue() while CPUs are being
    taken up and down anyway.

    Greetings,
    Rafael
    -
    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: 2007-05-14 00:19    [W:0.021 / U:1.400 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site