On Tue, Sep 04, 2007 at 07:35:21PM -0400, Chuck Ebbert wrote:
> On 08/28/2007 06:27 PM, Siddha, Suresh B wrote:
> > Try to fix MC/HT scheduler optimization breakage again, with out breaking
> > the FUZZ logic.
> >
> > First fix the check
> > if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task)
> > with this
> > if (*imbalance < busiest_load_per_task)
> >
> > As the current check is always false for nice 0 tasks (as
> > SCHED_LOAD_SCALE_FUZZ
> > is same as busiest_load_per_task for nice 0 tasks).
> >
> > With the above change, imbalance was getting reset to 0 in the corner case
> > condition, making the FUZZ logic fail. Fix it by not corrupting the
> > imbalance and change the imbalance, only when it finds that the
> > HT/MC optimization is needed.
> >
> > Signed-off-by: Suresh Siddha <[EMAIL PROTECTED]>
> > ---
> >
> > diff --git a/kernel/sched.c b/kernel/sched.c
> > index 9fe473a..03e5e8d 100644
> > --- a/kernel/sched.c
> > +++ b/kernel/sched.c
> > @@ -2511,7 +2511,7 @@ group_next:
> > * a think about bumping its value to force at least one task to be
> > * moved
> > */
> > - if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task) {
> > + if (*imbalance < busiest_load_per_task) {
> > unsigned long tmp, pwr_now, pwr_move;
> > unsigned int imbn;
> >
> > @@ -2563,10 +2563,8 @@ small_imbalance:
> > pwr_move /= SCHED_LOAD_SCALE;
> >
> > /* Move if we gain throughput */
> > - if (pwr_move <= pwr_now)
> > - goto out_balanced;
> > -
> > - *imbalance = busiest_load_per_task;
> > + if (pwr_move > pwr_now)
> > + *imbalance = busiest_load_per_task;
> > }
> >
> > return busiest;
>
> Seems this didn't get merged? Latest git as of today still has the code
> as it was before this patch.
This is must fix for .23 and Ingo previously mentioned that he will push it
for .23
Ingo?
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