diff options
| -rw-r--r-- | kernel/sched/fair.c | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0ef7e0a67089..a78d2e3b9d49 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6868,9 +6868,8 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) { struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_rq_mask); unsigned long prev_delta = ULONG_MAX, best_delta = ULONG_MAX; - int cpu, best_energy_cpu = prev_cpu, target = -1; struct root_domain *rd = this_rq()->rd; - unsigned long base_energy = 0; + int cpu, best_energy_cpu, target = -1; struct sched_domain *sd; struct perf_domain *pd; struct energy_env eenv; @@ -6902,8 +6901,8 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) unsigned long cpu_cap, cpu_thermal_cap, util; unsigned long cur_delta, max_spare_cap = 0; bool compute_prev_delta = false; - unsigned long base_energy_pd; int max_spare_cap_cpu = -1; + unsigned long base_energy; cpumask_and(cpus, perf_domain_span(pd), cpu_online_mask); @@ -6961,17 +6960,16 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) eenv_pd_busy_time(&eenv, cpus, p); /* Compute the 'base' energy of the pd, without @p */ - base_energy_pd = compute_energy(&eenv, pd, cpus, p, -1); - base_energy += base_energy_pd; + base_energy = compute_energy(&eenv, pd, cpus, p, -1); /* Evaluate the energy impact of using prev_cpu. */ if (compute_prev_delta) { prev_delta = compute_energy(&eenv, pd, cpus, p, prev_cpu); /* CPU utilization has changed */ - if (prev_delta < base_energy_pd) + if (prev_delta < base_energy) goto unlock; - prev_delta -= base_energy_pd; + prev_delta -= base_energy; best_delta = min(best_delta, prev_delta); } @@ -6980,9 +6978,9 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) cur_delta = compute_energy(&eenv, pd, cpus, p, max_spare_cap_cpu); /* CPU utilization has changed */ - if (cur_delta < base_energy_pd) + if (cur_delta < base_energy) goto unlock; - cur_delta -= base_energy_pd; + cur_delta -= base_energy; if (cur_delta < best_delta) { best_delta = cur_delta; best_energy_cpu = max_spare_cap_cpu; @@ -6991,12 +6989,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) } rcu_read_unlock(); - /* - * Pick the best CPU if prev_cpu cannot be used, or if it saves at - * least 6% of the energy used by prev_cpu. - */ - if ((prev_delta == ULONG_MAX) || - (prev_delta - best_delta) > ((prev_delta + base_energy) >> 4)) + if (best_delta < prev_delta) target = best_energy_cpu; return target; |