diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/topology.c | 39 |
1 files changed, 3 insertions, 36 deletions
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 1cc595907363..fcda3f066eec 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -348,32 +348,13 @@ static void sched_energy_set(bool has_eas) * 1. an Energy Model (EM) is available; * 2. the SD_ASYM_CPUCAPACITY flag is set in the sched_domain hierarchy. * 3. no SMT is detected. - * 4. the EM complexity is low enough to keep scheduling overheads low; - * 5. schedutil is driving the frequency of all CPUs of the rd; - * 6. frequency invariance support is present; - * - * The complexity of the Energy Model is defined as: - * - * C = nr_pd * (nr_cpus + nr_ps) - * - * with parameters defined as: - * - nr_pd: the number of performance domains - * - nr_cpus: the number of CPUs - * - nr_ps: the sum of the number of performance states of all performance - * domains (for example, on a system with 2 performance domains, - * with 10 performance states each, nr_ps = 2 * 10 = 20). - * - * It is generally not a good idea to use such a model in the wake-up path on - * very complex platforms because of the associated scheduling overheads. The - * arbitrary constraint below prevents that. It makes EAS usable up to 16 CPUs - * with per-CPU DVFS and less than 8 performance states each, for example. + * 4. schedutil is driving the frequency of all CPUs of the rd; + * 5. frequency invariance support is present; */ -#define EM_MAX_COMPLEXITY 2048 - extern struct cpufreq_governor schedutil_gov; static bool build_perf_domains(const struct cpumask *cpu_map) { - int i, nr_pd = 0, nr_ps = 0, nr_cpus = cpumask_weight(cpu_map); + int i; struct perf_domain *pd = NULL, *tmp; int cpu = cpumask_first(cpu_map); struct root_domain *rd = cpu_rq(cpu)->rd; @@ -431,20 +412,6 @@ static bool build_perf_domains(const struct cpumask *cpu_map) goto free; tmp->next = pd; pd = tmp; - - /* - * Count performance domains and performance states for the - * complexity check. - */ - nr_pd++; - nr_ps += em_pd_nr_perf_states(pd->em_pd); - } - - /* Bail out if the Energy Model complexity is too high. */ - if (nr_pd * (nr_ps + nr_cpus) > EM_MAX_COMPLEXITY) { - WARN(1, "rd %*pbl: Failed to start EAS, EM complexity is too high\n", - cpumask_pr_args(cpu_map)); - goto free; } perf_domain_debug(cpu_map, pd); |