diff options
| author | Dietmar Eggemann <dietmar.eggemann@arm.com> | 2015-01-26 19:47:28 +0000 |
|---|---|---|
| committer | Leo Yan <leo.yan@linaro.org> | 2016-05-10 16:49:49 +0800 |
| commit | cda2bd333be6e5e8c38fa072c9c4c296312dfd8d (patch) | |
| tree | 8707e66be01c969ea77d0281b95bce399821234e /kernel/sched/fair.c | |
| parent | 8a5c0339bb7b7eedd2e75b62ebe4144a195f7ef3 (diff) | |
sched: Enable idle balance to pull single task towards cpu with higher capacity
We do not want to miss out on the ability to pull a single remaining
task from a potential source cpu towards an idle destination cpu. Add an
extra criteria to need_active_balance() to kick off active load balance
if the source cpu is over-utilized and has lower capacity than the
destination cpu.
cc: Ingo Molnar <mingo@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Diffstat (limited to 'kernel/sched/fair.c')
| -rw-r--r-- | kernel/sched/fair.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index bebc8367edee..fe40cdb8e640 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4779,6 +4779,11 @@ static inline bool task_fits_spare(struct task_struct *p, int cpu) return __task_fits(p, cpu, cpu_util(cpu)); } +static bool cpu_overutilized(int cpu) +{ + return (capacity_of(cpu) * 1024) < (cpu_util(cpu) * capacity_margin); +} + /* * find_idlest_group finds and returns the least busy CPU group within the * domain. @@ -6995,6 +7000,13 @@ static int need_active_balance(struct lb_env *env) return 1; } + if ((capacity_of(env->src_cpu) < capacity_of(env->dst_cpu)) && + env->src_rq->cfs.h_nr_running == 1 && + cpu_overutilized(env->src_cpu) && + !cpu_overutilized(env->dst_cpu)) { + return 1; + } + return unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2); } |