From 0605f407b95f3811588e4532a6dae272c7fa1d8d Mon Sep 17 00:00:00 2001 From: Dietmar Eggemann Date: Fri, 14 Nov 2014 16:20:20 +0000 Subject: [PATCH] sched: Initialize energy data structures The sched_group_energy (sge) pointer of the first sched_group (sg) in the sched_domain (sd) is initialized to point to the appropriate (in terms of sd level and cpu) sge data defined in the arch and so to the correct part of the Energy Model (EM). Energy-aware scheduling allows that a system has only EM data up to a certain sd level (so called highest energy aware balancing sd level). A check in init_sched_energy() enforces that all sd's below this sd level contain EM data. The 'int cpu' parameter of sched_domain_energy_f requires that check_sched_energy_data() makes sure that all cpus spanned by a sg are provisioned with the same EM data. This patch has also been tested with feature FORCE_SD_OVERLAP enabled. cc: Ingo Molnar cc: Peter Zijlstra Signed-off-by: Dietmar Eggemann --- kernel/sched/core.c | 65 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 64 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 8bf755697230..e4be7f09d46b 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6308,6 +6308,66 @@ static void init_sched_groups_capacity(int cpu, struct sched_domain *sd) atomic_set(&sg->sgc->nr_busy_cpus, sg->group_weight); } +/* + * Check that the per-cpu provided sd energy data is consistent for all cpus + * within the mask. + */ +static inline void check_sched_energy_data(int cpu, sched_domain_energy_f fn, + const struct cpumask *cpumask) +{ + const struct sched_group_energy * const sge = fn(cpu); + struct cpumask mask; + int i; + + if (cpumask_weight(cpumask) <= 1) + return; + + cpumask_xor(&mask, cpumask, get_cpu_mask(cpu)); + + for_each_cpu(i, &mask) { + const struct sched_group_energy * const e = fn(i); + int y; + + BUG_ON(e->nr_idle_states != sge->nr_idle_states); + + for (y = 0; y < (e->nr_idle_states); y++) { + BUG_ON(e->idle_states[y].power != + sge->idle_states[y].power); + } + + BUG_ON(e->nr_cap_states != sge->nr_cap_states); + + for (y = 0; y < (e->nr_cap_states); y++) { + BUG_ON(e->cap_states[y].cap != sge->cap_states[y].cap); + BUG_ON(e->cap_states[y].power != + sge->cap_states[y].power); + } + } +} + +static void init_sched_energy(int cpu, struct sched_domain *sd, + sched_domain_energy_f fn) +{ + if (!(fn && fn(cpu))) + return; + + if (cpu != group_balance_cpu(sd->groups)) + return; + + if (sd->child && !sd->child->groups->sge) { + pr_err("BUG: EAS setup broken for CPU%d\n", cpu); +#ifdef CONFIG_SCHED_DEBUG + pr_err(" energy data on %s but not on %s domain\n", + sd->name, sd->child->name); +#endif + return; + } + + check_sched_energy_data(cpu, fn, sched_group_cpus(sd->groups)); + + sd->groups->sge = fn(cpu); +} + /* * Initializers for schedule domains * Non-inlined to reduce accumulated stack pressure in build_sched_domains() @@ -7014,10 +7074,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, /* Calculate CPU capacity for physical packages and nodes */ for (i = nr_cpumask_bits-1; i >= 0; i--) { + struct sched_domain_topology_level *tl = sched_domain_topology; + if (!cpumask_test_cpu(i, cpu_map)) continue; - for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent, tl++) { + init_sched_energy(i, sd, tl->energy); claim_allocations(i, sd); init_sched_groups_capacity(i, sd); } -- 2.34.1