Messages in this thread | | | Subject | Re: [RFC PATCH] sched: Pass affine target cpu into wake_affine | From | Lin Ming <> | Date | Tue, 05 Jan 2010 10:48:06 +0800 |
| |
On Mon, 2010-01-04 at 17:03 +0800, Lin Ming wrote: > commit a03ecf08d7bbdd979d81163ea13d194fe21ad339 > Author: Lin Ming <ming.m.lin@intel.com> > Date: Mon Jan 4 14:14:50 2010 +0800 > > sched: Pass affine target cpu into wake_affine > > Since commit a1f84a3(sched: Check for an idle shared cache in select_task_rq_fair()), > the affine target maybe adjusted to any idle cpu in cache sharing domains > instead of current cpu. > But wake_affine still use current cpu to calculate load which is wrong. > > This patch passes affine cpu into wake_affine. > > Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Mike,
Any comment of this patch?
Thanks, Lin Ming
> --- > kernel/sched_fair.c | 29 ++++++++++++++--------------- > 1 files changed, 14 insertions(+), 15 deletions(-) > > diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c > index 42ac3c9..0a6fa39 100644 > --- a/kernel/sched_fair.c > +++ b/kernel/sched_fair.c > @@ -1237,11 +1237,11 @@ static inline unsigned long effective_load(struct task_group *tg, int cpu, > > #endif > > -static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) > +static int wake_affine(struct sched_domain *sd, struct task_struct *p, int affine_cpu, int sync) > { > struct task_struct *curr = current; > - unsigned long this_load, load; > - int idx, this_cpu, prev_cpu; > + unsigned long affine_load, load; > + int idx, prev_cpu; > unsigned long tl_per_task; > unsigned int imbalance; > struct task_group *tg; > @@ -1249,10 +1249,9 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) > int balanced; > > idx = sd->wake_idx; > - this_cpu = smp_processor_id(); > prev_cpu = task_cpu(p); > load = source_load(prev_cpu, idx); > - this_load = target_load(this_cpu, idx); > + affine_load = target_load(affine_cpu, idx); > > if (sync) { > if (sched_feat(SYNC_LESS) && > @@ -1275,7 +1274,7 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) > tg = task_group(current); > weight = current->se.load.weight; > > - this_load += effective_load(tg, this_cpu, -weight, -weight); > + affine_load += effective_load(tg, affine_cpu, -weight, -weight); > load += effective_load(tg, prev_cpu, 0, -weight); > } > > @@ -1285,16 +1284,16 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) > imbalance = 100 + (sd->imbalance_pct - 100) / 2; > > /* > - * In low-load situations, where prev_cpu is idle and this_cpu is idle > - * due to the sync cause above having dropped this_load to 0, we'll > + * In low-load situations, where prev_cpu is idle and affine_cpu is idle > + * due to the sync cause above having dropped affine_load to 0, we'll > * always have an imbalance, but there's really nothing you can do > * about that, so that's good too. > * > * Otherwise check if either cpus are near enough in load to allow this > - * task to be woken on this_cpu. > + * task to be woken on affine_cpu. > */ > - balanced = !this_load || > - 100*(this_load + effective_load(tg, this_cpu, weight, weight)) <= > + balanced = !affine_load || > + 100*(affine_load + effective_load(tg, affine_cpu, weight, weight)) <= > imbalance*(load + effective_load(tg, prev_cpu, 0, weight)); > > /* > @@ -1306,11 +1305,11 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) > return 1; > > schedstat_inc(p, se.nr_wakeups_affine_attempts); > - tl_per_task = cpu_avg_load_per_task(this_cpu); > + tl_per_task = cpu_avg_load_per_task(affine_cpu); > > if (balanced || > - (this_load <= load && > - this_load + target_load(prev_cpu, idx) <= tl_per_task)) { > + (affine_load <= load && > + affine_load + target_load(prev_cpu, idx) <= tl_per_task)) { > /* > * This domain has SD_WAKE_AFFINE and > * p is cache cold in this domain, and > @@ -1544,7 +1543,7 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag > update_shares(tmp); > } > > - if (affine_sd && wake_affine(affine_sd, p, sync)) > + if (affine_sd && wake_affine(affine_sd, p, cpu, sync)) > return cpu; > > while (sd) { >
| |