lkml.org 
[lkml]   [2009]   [Feb]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH v2] NOHZ: fix nohz on cpu unplug
    Date
    Am Tuesday 03 February 2009 00:57:03 schrieb Suresh Siddha:
    > Does this patch fix the issue? Thanks.

    I fixed up a compile error. (See below). After that, the patch does indeed fix
    the problem.

    Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>


    > diff --git a/kernel/sched.c b/kernel/sched.c
    > index 96439a4..8a0419b 100644
    > --- a/kernel/sched.c
    > +++ b/kernel/sched.c
    > @@ -4026,19 +4026,24 @@ int select_nohz_load_balancer(int stop_tick)
    > int cpu = smp_processor_id();
    >
    > if (stop_tick) {
    > - cpumask_set_cpu(cpu, nohz.cpu_mask);
    > cpu_rq(cpu)->in_nohz_recently = 1;
    >
    > - /*
    > - * If we are going offline and still the leader, give up!
    > - */
    > - if (!cpu_active(cpu) &&
    > - atomic_read(&nohz.load_balancer) == cpu) {
    > + if (!cpu_active(cpu) {

    That does not compile...I used the following:
    if (!cpu_active(cpu)) {

    > + if (atomic_read(&nohz.load_balancer) != cpu)
    > + return 0;
    > +
    > + /*
    > + * If we are going offline and still the leader,
    > + * give up!
    > + */
    > if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
    > BUG();
    > +
    > return 0;
    > }
    >
    > + cpumask_set_cpu(cpu, nohz.cpu_mask);
    > +
    > /* time for ilb owner also to sleep */
    > if (cpumask_weight(nohz.cpu_mask) == num_online_cpus()) {
    > if (atomic_read(&nohz.load_balancer) == cpu)




    \
     
     \ /
      Last update: 2009-02-03 09:51    [W:0.021 / U:0.360 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site