// SPDX-License-Identifier: GPL-2.0
|
/*
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* Scheduler topology setup/handling methods
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*/
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#include "sched.h"
|
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DEFINE_MUTEX(sched_domains_mutex);
|
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/* Protected by sched_domains_mutex: */
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cpumask_var_t sched_domains_tmpmask;
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cpumask_var_t sched_domains_tmpmask2;
|
|
#ifdef CONFIG_SCHED_DEBUG
|
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static int __init sched_debug_setup(char *str)
|
{
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sched_debug_enabled = true;
|
|
return 0;
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}
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early_param("sched_debug", sched_debug_setup);
|
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static inline bool sched_debug(void)
|
{
|
return sched_debug_enabled;
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}
|
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static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
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struct cpumask *groupmask)
|
{
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struct sched_group *group = sd->groups;
|
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cpumask_clear(groupmask);
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printk(KERN_DEBUG "%*s domain-%d: ", level, "", level);
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if (!(sd->flags & SD_LOAD_BALANCE)) {
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printk("does not load-balance\n");
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if (sd->parent)
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printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain has parent");
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return -1;
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}
|
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printk(KERN_CONT "span=%*pbl level=%s\n",
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cpumask_pr_args(sched_domain_span(sd)), sd->name);
|
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if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) {
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printk(KERN_ERR "ERROR: domain->span does not contain CPU%d\n", cpu);
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}
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if (group && !cpumask_test_cpu(cpu, sched_group_span(group))) {
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printk(KERN_ERR "ERROR: domain->groups does not contain CPU%d\n", cpu);
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}
|
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printk(KERN_DEBUG "%*s groups:", level + 1, "");
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do {
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if (!group) {
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printk("\n");
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printk(KERN_ERR "ERROR: group is NULL\n");
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break;
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}
|
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if (!cpumask_weight(sched_group_span(group))) {
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printk(KERN_CONT "\n");
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printk(KERN_ERR "ERROR: empty group\n");
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break;
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}
|
|
if (!(sd->flags & SD_OVERLAP) &&
|
cpumask_intersects(groupmask, sched_group_span(group))) {
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printk(KERN_CONT "\n");
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printk(KERN_ERR "ERROR: repeated CPUs\n");
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break;
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}
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cpumask_or(groupmask, groupmask, sched_group_span(group));
|
|
printk(KERN_CONT " %d:{ span=%*pbl",
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group->sgc->id,
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cpumask_pr_args(sched_group_span(group)));
|
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if ((sd->flags & SD_OVERLAP) &&
|
!cpumask_equal(group_balance_mask(group), sched_group_span(group))) {
|
printk(KERN_CONT " mask=%*pbl",
|
cpumask_pr_args(group_balance_mask(group)));
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}
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if (group->sgc->capacity != SCHED_CAPACITY_SCALE)
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printk(KERN_CONT " cap=%lu", group->sgc->capacity);
|
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if (group == sd->groups && sd->child &&
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!cpumask_equal(sched_domain_span(sd->child),
|
sched_group_span(group))) {
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printk(KERN_ERR "ERROR: domain->groups does not match domain->child\n");
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}
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printk(KERN_CONT " }");
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group = group->next;
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if (group != sd->groups)
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printk(KERN_CONT ",");
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} while (group != sd->groups);
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printk(KERN_CONT "\n");
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if (!cpumask_equal(sched_domain_span(sd), groupmask))
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printk(KERN_ERR "ERROR: groups don't span domain->span\n");
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if (sd->parent &&
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!cpumask_subset(groupmask, sched_domain_span(sd->parent)))
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printk(KERN_ERR "ERROR: parent span is not a superset of domain->span\n");
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return 0;
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}
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static void sched_domain_debug(struct sched_domain *sd, int cpu)
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{
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int level = 0;
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if (!sched_debug_enabled)
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return;
|
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if (!sd) {
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printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
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return;
|
}
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printk(KERN_DEBUG "CPU%d attaching sched-domain(s):\n", cpu);
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for (;;) {
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if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask))
|
break;
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level++;
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sd = sd->parent;
|
if (!sd)
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break;
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}
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}
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#else /* !CONFIG_SCHED_DEBUG */
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# define sched_debug_enabled 0
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# define sched_domain_debug(sd, cpu) do { } while (0)
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static inline bool sched_debug(void)
|
{
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return false;
|
}
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#endif /* CONFIG_SCHED_DEBUG */
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static int sd_degenerate(struct sched_domain *sd)
|
{
|
if (cpumask_weight(sched_domain_span(sd)) == 1)
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return 1;
|
|
/* Following flags need at least 2 groups */
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if (sd->flags & (SD_LOAD_BALANCE |
|
SD_BALANCE_NEWIDLE |
|
SD_BALANCE_FORK |
|
SD_BALANCE_EXEC |
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SD_SHARE_CPUCAPACITY |
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SD_ASYM_CPUCAPACITY |
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SD_SHARE_PKG_RESOURCES |
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SD_SHARE_POWERDOMAIN)) {
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if (sd->groups != sd->groups->next)
|
return 0;
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}
|
|
/* Following flags don't use groups */
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if (sd->flags & (SD_WAKE_AFFINE))
|
return 0;
|
|
return 1;
|
}
|
|
static int
|
sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
|
{
|
unsigned long cflags = sd->flags, pflags = parent->flags;
|
|
if (sd_degenerate(parent))
|
return 1;
|
|
if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent)))
|
return 0;
|
|
/* Flags needing groups don't count if only 1 group in parent */
|
if (parent->groups == parent->groups->next) {
|
pflags &= ~(SD_LOAD_BALANCE |
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SD_BALANCE_NEWIDLE |
|
SD_BALANCE_FORK |
|
SD_BALANCE_EXEC |
|
SD_ASYM_CPUCAPACITY |
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SD_SHARE_CPUCAPACITY |
|
SD_SHARE_PKG_RESOURCES |
|
SD_PREFER_SIBLING |
|
SD_SHARE_POWERDOMAIN);
|
if (nr_node_ids == 1)
|
pflags &= ~SD_SERIALIZE;
|
}
|
if (~cflags & pflags)
|
return 0;
|
|
return 1;
|
}
|
|
DEFINE_STATIC_KEY_FALSE(sched_energy_present);
|
|
#ifdef CONFIG_ENERGY_MODEL
|
#if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
|
unsigned int sysctl_sched_energy_aware = 1;
|
DEFINE_MUTEX(sched_energy_mutex);
|
bool sched_energy_update;
|
|
#ifdef CONFIG_PROC_SYSCTL
|
int sched_energy_aware_handler(struct ctl_table *table, int write,
|
void __user *buffer, size_t *lenp, loff_t *ppos)
|
{
|
int ret, state;
|
|
if (write && !capable(CAP_SYS_ADMIN))
|
return -EPERM;
|
|
ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
|
if (!ret && write) {
|
state = static_branch_unlikely(&sched_energy_present);
|
if (state != sysctl_sched_energy_aware) {
|
mutex_lock(&sched_energy_mutex);
|
sched_energy_update = 1;
|
rebuild_sched_domains();
|
sched_energy_update = 0;
|
mutex_unlock(&sched_energy_mutex);
|
}
|
}
|
|
return ret;
|
}
|
#endif
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#endif /* defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
|
|
static void free_pd(struct perf_domain *pd)
|
{
|
struct perf_domain *tmp;
|
|
while (pd) {
|
tmp = pd->next;
|
kfree(pd);
|
pd = tmp;
|
}
|
}
|
|
static struct perf_domain *find_pd(struct perf_domain *pd, int cpu)
|
{
|
while (pd) {
|
if (cpumask_test_cpu(cpu, perf_domain_span(pd)))
|
return pd;
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pd = pd->next;
|
}
|
|
return NULL;
|
}
|
|
static struct perf_domain *pd_init(int cpu)
|
{
|
struct em_perf_domain *obj = em_cpu_get(cpu);
|
struct perf_domain *pd;
|
|
if (!obj) {
|
if (sched_debug())
|
pr_info("%s: no EM found for CPU%d\n", __func__, cpu);
|
return NULL;
|
}
|
|
pd = kzalloc(sizeof(*pd), GFP_KERNEL);
|
if (!pd)
|
return NULL;
|
pd->em_pd = obj;
|
|
return pd;
|
}
|
|
static void perf_domain_debug(const struct cpumask *cpu_map,
|
struct perf_domain *pd)
|
{
|
if (!sched_debug() || !pd)
|
return;
|
|
printk(KERN_DEBUG "root_domain %*pbl:", cpumask_pr_args(cpu_map));
|
|
while (pd) {
|
printk(KERN_CONT " pd%d:{ cpus=%*pbl nr_cstate=%d }",
|
cpumask_first(perf_domain_span(pd)),
|
cpumask_pr_args(perf_domain_span(pd)),
|
em_pd_nr_cap_states(pd->em_pd));
|
pd = pd->next;
|
}
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|
printk(KERN_CONT "\n");
|
}
|
|
static void destroy_perf_domain_rcu(struct rcu_head *rp)
|
{
|
struct perf_domain *pd;
|
|
pd = container_of(rp, struct perf_domain, rcu);
|
free_pd(pd);
|
}
|
|
static void sched_energy_set(bool has_eas)
|
{
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if (!has_eas && static_branch_unlikely(&sched_energy_present)) {
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if (sched_debug())
|
pr_info("%s: stopping EAS\n", __func__);
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static_branch_disable_cpuslocked(&sched_energy_present);
|
} else if (has_eas && !static_branch_unlikely(&sched_energy_present)) {
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if (sched_debug())
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pr_info("%s: starting EAS\n", __func__);
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static_branch_enable_cpuslocked(&sched_energy_present);
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}
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}
|
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/*
|
* EAS can be used on a root domain if it meets all the following conditions:
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* 1. an Energy Model (EM) is available;
|
* 2. the SD_ASYM_CPUCAPACITY flag is set in the sched_domain hierarchy.
|
* 3. the EM complexity is low enough to keep scheduling overheads low;
|
*
|
* The complexity of the Energy Model is defined as:
|
*
|
* C = nr_pd * (nr_cpus + nr_cs)
|
*
|
* with parameters defined as:
|
* - nr_pd: the number of performance domains
|
* - nr_cpus: the number of CPUs
|
* - nr_cs: the sum of the number of capacity states of all performance
|
* domains (for example, on a system with 2 performance domains,
|
* with 10 capacity states each, nr_cs = 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 capacity states each, for example.
|
*/
|
#define EM_MAX_COMPLEXITY 2048
|
|
static bool build_perf_domains(const struct cpumask *cpu_map)
|
{
|
int i, nr_pd = 0, nr_cs = 0, nr_cpus = cpumask_weight(cpu_map);
|
struct perf_domain *pd = NULL, *tmp;
|
int cpu = cpumask_first(cpu_map);
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struct root_domain *rd = cpu_rq(cpu)->rd;
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|
#if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
|
if (!sysctl_sched_energy_aware)
|
goto free;
|
#endif
|
|
/* EAS is enabled for asymmetric CPU capacity topologies. */
|
if (!per_cpu(sd_asym_cpucapacity, cpu)) {
|
if (sched_debug()) {
|
pr_info("rd %*pbl: CPUs do not have asymmetric capacities\n",
|
cpumask_pr_args(cpu_map));
|
}
|
goto free;
|
}
|
|
for_each_cpu(i, cpu_map) {
|
/* Skip already covered CPUs. */
|
if (find_pd(pd, i))
|
continue;
|
|
/* Create the new pd and add it to the local list. */
|
tmp = pd_init(i);
|
if (!tmp)
|
goto free;
|
tmp->next = pd;
|
pd = tmp;
|
|
/*
|
* Count performance domains and capacity states for the
|
* complexity check.
|
*/
|
nr_pd++;
|
nr_cs += em_pd_nr_cap_states(pd->em_pd);
|
}
|
|
/* Bail out if the Energy Model complexity is too high. */
|
if (nr_pd * (nr_cs + 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);
|
|
/* Attach the new list of performance domains to the root domain. */
|
tmp = rd->pd;
|
rcu_assign_pointer(rd->pd, pd);
|
if (tmp)
|
call_rcu(&tmp->rcu, destroy_perf_domain_rcu);
|
|
return !!pd;
|
|
free:
|
free_pd(pd);
|
tmp = rd->pd;
|
rcu_assign_pointer(rd->pd, NULL);
|
if (tmp)
|
call_rcu(&tmp->rcu, destroy_perf_domain_rcu);
|
|
return false;
|
}
|
#else
|
static void free_pd(struct perf_domain *pd) { }
|
#endif /* CONFIG_ENERGY_MODEL */
|
|
static void free_rootdomain(struct rcu_head *rcu)
|
{
|
struct root_domain *rd = container_of(rcu, struct root_domain, rcu);
|
|
cpupri_cleanup(&rd->cpupri);
|
cpudl_cleanup(&rd->cpudl);
|
free_cpumask_var(rd->dlo_mask);
|
free_cpumask_var(rd->rto_mask);
|
free_cpumask_var(rd->online);
|
free_cpumask_var(rd->span);
|
free_pd(rd->pd);
|
kfree(rd);
|
}
|
|
void rq_attach_root(struct rq *rq, struct root_domain *rd)
|
{
|
struct root_domain *old_rd = NULL;
|
unsigned long flags;
|
|
raw_spin_lock_irqsave(&rq->lock, flags);
|
|
if (rq->rd) {
|
old_rd = rq->rd;
|
|
if (cpumask_test_cpu(rq->cpu, old_rd->online))
|
set_rq_offline(rq);
|
|
cpumask_clear_cpu(rq->cpu, old_rd->span);
|
|
/*
|
* If we dont want to free the old_rd yet then
|
* set old_rd to NULL to skip the freeing later
|
* in this function:
|
*/
|
if (!atomic_dec_and_test(&old_rd->refcount))
|
old_rd = NULL;
|
}
|
|
atomic_inc(&rd->refcount);
|
rq->rd = rd;
|
|
cpumask_set_cpu(rq->cpu, rd->span);
|
if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
|
set_rq_online(rq);
|
|
raw_spin_unlock_irqrestore(&rq->lock, flags);
|
|
if (old_rd)
|
call_rcu_sched(&old_rd->rcu, free_rootdomain);
|
}
|
|
void sched_get_rd(struct root_domain *rd)
|
{
|
atomic_inc(&rd->refcount);
|
}
|
|
void sched_put_rd(struct root_domain *rd)
|
{
|
if (!atomic_dec_and_test(&rd->refcount))
|
return;
|
|
call_rcu_sched(&rd->rcu, free_rootdomain);
|
}
|
|
static int init_rootdomain(struct root_domain *rd)
|
{
|
if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL))
|
goto out;
|
if (!zalloc_cpumask_var(&rd->online, GFP_KERNEL))
|
goto free_span;
|
if (!zalloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
|
goto free_online;
|
if (!zalloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
|
goto free_dlo_mask;
|
|
#ifdef HAVE_RT_PUSH_IPI
|
rd->rto_cpu = -1;
|
raw_spin_lock_init(&rd->rto_lock);
|
init_irq_work(&rd->rto_push_work, rto_push_irq_work_func);
|
rd->rto_push_work.flags |= IRQ_WORK_HARD_IRQ;
|
#endif
|
|
init_dl_bw(&rd->dl_bw);
|
if (cpudl_init(&rd->cpudl) != 0)
|
goto free_rto_mask;
|
|
if (cpupri_init(&rd->cpupri) != 0)
|
goto free_cpudl;
|
|
init_max_cpu_capacity(&rd->max_cpu_capacity);
|
|
return 0;
|
|
free_cpudl:
|
cpudl_cleanup(&rd->cpudl);
|
free_rto_mask:
|
free_cpumask_var(rd->rto_mask);
|
free_dlo_mask:
|
free_cpumask_var(rd->dlo_mask);
|
free_online:
|
free_cpumask_var(rd->online);
|
free_span:
|
free_cpumask_var(rd->span);
|
out:
|
return -ENOMEM;
|
}
|
|
/*
|
* By default the system creates a single root-domain with all CPUs as
|
* members (mimicking the global state we have today).
|
*/
|
struct root_domain def_root_domain;
|
|
void init_defrootdomain(void)
|
{
|
init_rootdomain(&def_root_domain);
|
|
atomic_set(&def_root_domain.refcount, 1);
|
}
|
|
static struct root_domain *alloc_rootdomain(void)
|
{
|
struct root_domain *rd;
|
|
rd = kzalloc(sizeof(*rd), GFP_KERNEL);
|
if (!rd)
|
return NULL;
|
|
if (init_rootdomain(rd) != 0) {
|
kfree(rd);
|
return NULL;
|
}
|
|
return rd;
|
}
|
|
static void free_sched_groups(struct sched_group *sg, int free_sgc)
|
{
|
struct sched_group *tmp, *first;
|
|
if (!sg)
|
return;
|
|
first = sg;
|
do {
|
tmp = sg->next;
|
|
if (free_sgc && atomic_dec_and_test(&sg->sgc->ref))
|
kfree(sg->sgc);
|
|
if (atomic_dec_and_test(&sg->ref))
|
kfree(sg);
|
sg = tmp;
|
} while (sg != first);
|
}
|
|
static void destroy_sched_domain(struct sched_domain *sd)
|
{
|
/*
|
* A normal sched domain may have multiple group references, an
|
* overlapping domain, having private groups, only one. Iterate,
|
* dropping group/capacity references, freeing where none remain.
|
*/
|
free_sched_groups(sd->groups, 1);
|
|
if (sd->shared && atomic_dec_and_test(&sd->shared->ref))
|
kfree(sd->shared);
|
kfree(sd);
|
}
|
|
static void destroy_sched_domains_rcu(struct rcu_head *rcu)
|
{
|
struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu);
|
|
while (sd) {
|
struct sched_domain *parent = sd->parent;
|
destroy_sched_domain(sd);
|
sd = parent;
|
}
|
}
|
|
static void destroy_sched_domains(struct sched_domain *sd)
|
{
|
if (sd)
|
call_rcu(&sd->rcu, destroy_sched_domains_rcu);
|
}
|
|
/*
|
* Keep a special pointer to the highest sched_domain that has
|
* SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this
|
* allows us to avoid some pointer chasing select_idle_sibling().
|
*
|
* Also keep a unique ID per domain (we use the first CPU number in
|
* the cpumask of the domain), this allows us to quickly tell if
|
* two CPUs are in the same cache domain, see cpus_share_cache().
|
*/
|
DEFINE_PER_CPU(struct sched_domain *, sd_llc);
|
DEFINE_PER_CPU(int, sd_llc_size);
|
DEFINE_PER_CPU(int, sd_llc_id);
|
DEFINE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
|
DEFINE_PER_CPU(struct sched_domain *, sd_numa);
|
DEFINE_PER_CPU(struct sched_domain *, sd_asym_packing);
|
DEFINE_PER_CPU(struct sched_domain *, sd_asym_cpucapacity);
|
DEFINE_STATIC_KEY_FALSE(sched_asym_cpucapacity);
|
|
static void update_top_cache_domain(int cpu)
|
{
|
struct sched_domain_shared *sds = NULL;
|
struct sched_domain *sd;
|
int id = cpu;
|
int size = 1;
|
|
sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES);
|
if (sd) {
|
id = cpumask_first(sched_domain_span(sd));
|
size = cpumask_weight(sched_domain_span(sd));
|
sds = sd->shared;
|
}
|
|
rcu_assign_pointer(per_cpu(sd_llc, cpu), sd);
|
per_cpu(sd_llc_size, cpu) = size;
|
per_cpu(sd_llc_id, cpu) = id;
|
rcu_assign_pointer(per_cpu(sd_llc_shared, cpu), sds);
|
|
sd = lowest_flag_domain(cpu, SD_NUMA);
|
rcu_assign_pointer(per_cpu(sd_numa, cpu), sd);
|
|
sd = highest_flag_domain(cpu, SD_ASYM_PACKING);
|
rcu_assign_pointer(per_cpu(sd_asym_packing, cpu), sd);
|
|
sd = lowest_flag_domain(cpu, SD_ASYM_CPUCAPACITY);
|
rcu_assign_pointer(per_cpu(sd_asym_cpucapacity, cpu), sd);
|
}
|
|
/*
|
* Attach the domain 'sd' to 'cpu' as its base domain. Callers must
|
* hold the hotplug lock.
|
*/
|
static void
|
cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
|
{
|
struct rq *rq = cpu_rq(cpu);
|
struct sched_domain *tmp;
|
|
/* Remove the sched domains which do not contribute to scheduling. */
|
for (tmp = sd; tmp; ) {
|
struct sched_domain *parent = tmp->parent;
|
if (!parent)
|
break;
|
|
if (sd_parent_degenerate(tmp, parent)) {
|
tmp->parent = parent->parent;
|
if (parent->parent)
|
parent->parent->child = tmp;
|
/*
|
* Transfer SD_PREFER_SIBLING down in case of a
|
* degenerate parent; the spans match for this
|
* so the property transfers.
|
*/
|
if (parent->flags & SD_PREFER_SIBLING)
|
tmp->flags |= SD_PREFER_SIBLING;
|
destroy_sched_domain(parent);
|
} else
|
tmp = tmp->parent;
|
}
|
|
if (sd && sd_degenerate(sd)) {
|
tmp = sd;
|
sd = sd->parent;
|
destroy_sched_domain(tmp);
|
if (sd)
|
sd->child = NULL;
|
}
|
|
sched_domain_debug(sd, cpu);
|
|
rq_attach_root(rq, rd);
|
tmp = rq->sd;
|
rcu_assign_pointer(rq->sd, sd);
|
dirty_sched_domain_sysctl(cpu);
|
destroy_sched_domains(tmp);
|
|
update_top_cache_domain(cpu);
|
}
|
|
struct s_data {
|
struct sched_domain * __percpu *sd;
|
struct root_domain *rd;
|
};
|
|
enum s_alloc {
|
sa_rootdomain,
|
sa_sd,
|
sa_sd_storage,
|
sa_none,
|
};
|
|
/*
|
* Return the canonical balance CPU for this group, this is the first CPU
|
* of this group that's also in the balance mask.
|
*
|
* The balance mask are all those CPUs that could actually end up at this
|
* group. See build_balance_mask().
|
*
|
* Also see should_we_balance().
|
*/
|
int group_balance_cpu(struct sched_group *sg)
|
{
|
return cpumask_first(group_balance_mask(sg));
|
}
|
|
|
/*
|
* NUMA topology (first read the regular topology blurb below)
|
*
|
* Given a node-distance table, for example:
|
*
|
* node 0 1 2 3
|
* 0: 10 20 30 20
|
* 1: 20 10 20 30
|
* 2: 30 20 10 20
|
* 3: 20 30 20 10
|
*
|
* which represents a 4 node ring topology like:
|
*
|
* 0 ----- 1
|
* | |
|
* | |
|
* | |
|
* 3 ----- 2
|
*
|
* We want to construct domains and groups to represent this. The way we go
|
* about doing this is to build the domains on 'hops'. For each NUMA level we
|
* construct the mask of all nodes reachable in @level hops.
|
*
|
* For the above NUMA topology that gives 3 levels:
|
*
|
* NUMA-2 0-3 0-3 0-3 0-3
|
* groups: {0-1,3},{1-3} {0-2},{0,2-3} {1-3},{0-1,3} {0,2-3},{0-2}
|
*
|
* NUMA-1 0-1,3 0-2 1-3 0,2-3
|
* groups: {0},{1},{3} {0},{1},{2} {1},{2},{3} {0},{2},{3}
|
*
|
* NUMA-0 0 1 2 3
|
*
|
*
|
* As can be seen; things don't nicely line up as with the regular topology.
|
* When we iterate a domain in child domain chunks some nodes can be
|
* represented multiple times -- hence the "overlap" naming for this part of
|
* the topology.
|
*
|
* In order to minimize this overlap, we only build enough groups to cover the
|
* domain. For instance Node-0 NUMA-2 would only get groups: 0-1,3 and 1-3.
|
*
|
* Because:
|
*
|
* - the first group of each domain is its child domain; this
|
* gets us the first 0-1,3
|
* - the only uncovered node is 2, who's child domain is 1-3.
|
*
|
* However, because of the overlap, computing a unique CPU for each group is
|
* more complicated. Consider for instance the groups of NODE-1 NUMA-2, both
|
* groups include the CPUs of Node-0, while those CPUs would not in fact ever
|
* end up at those groups (they would end up in group: 0-1,3).
|
*
|
* To correct this we have to introduce the group balance mask. This mask
|
* will contain those CPUs in the group that can reach this group given the
|
* (child) domain tree.
|
*
|
* With this we can once again compute balance_cpu and sched_group_capacity
|
* relations.
|
*
|
* XXX include words on how balance_cpu is unique and therefore can be
|
* used for sched_group_capacity links.
|
*
|
*
|
* Another 'interesting' topology is:
|
*
|
* node 0 1 2 3
|
* 0: 10 20 20 30
|
* 1: 20 10 20 20
|
* 2: 20 20 10 20
|
* 3: 30 20 20 10
|
*
|
* Which looks a little like:
|
*
|
* 0 ----- 1
|
* | / |
|
* | / |
|
* | / |
|
* 2 ----- 3
|
*
|
* This topology is asymmetric, nodes 1,2 are fully connected, but nodes 0,3
|
* are not.
|
*
|
* This leads to a few particularly weird cases where the sched_domain's are
|
* not of the same number for each CPU. Consider:
|
*
|
* NUMA-2 0-3 0-3
|
* groups: {0-2},{1-3} {1-3},{0-2}
|
*
|
* NUMA-1 0-2 0-3 0-3 1-3
|
*
|
* NUMA-0 0 1 2 3
|
*
|
*/
|
|
|
/*
|
* Build the balance mask; it contains only those CPUs that can arrive at this
|
* group and should be considered to continue balancing.
|
*
|
* We do this during the group creation pass, therefore the group information
|
* isn't complete yet, however since each group represents a (child) domain we
|
* can fully construct this using the sched_domain bits (which are already
|
* complete).
|
*/
|
static void
|
build_balance_mask(struct sched_domain *sd, struct sched_group *sg, struct cpumask *mask)
|
{
|
const struct cpumask *sg_span = sched_group_span(sg);
|
struct sd_data *sdd = sd->private;
|
struct sched_domain *sibling;
|
int i;
|
|
cpumask_clear(mask);
|
|
for_each_cpu(i, sg_span) {
|
sibling = *per_cpu_ptr(sdd->sd, i);
|
|
/*
|
* Can happen in the asymmetric case, where these siblings are
|
* unused. The mask will not be empty because those CPUs that
|
* do have the top domain _should_ span the domain.
|
*/
|
if (!sibling->child)
|
continue;
|
|
/* If we would not end up here, we can't continue from here */
|
if (!cpumask_equal(sg_span, sched_domain_span(sibling->child)))
|
continue;
|
|
cpumask_set_cpu(i, mask);
|
}
|
|
/* We must not have empty masks here */
|
WARN_ON_ONCE(cpumask_empty(mask));
|
}
|
|
/*
|
* XXX: This creates per-node group entries; since the load-balancer will
|
* immediately access remote memory to construct this group's load-balance
|
* statistics having the groups node local is of dubious benefit.
|
*/
|
static struct sched_group *
|
build_group_from_child_sched_domain(struct sched_domain *sd, int cpu)
|
{
|
struct sched_group *sg;
|
struct cpumask *sg_span;
|
|
sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
|
GFP_KERNEL, cpu_to_node(cpu));
|
|
if (!sg)
|
return NULL;
|
|
sg_span = sched_group_span(sg);
|
if (sd->child)
|
cpumask_copy(sg_span, sched_domain_span(sd->child));
|
else
|
cpumask_copy(sg_span, sched_domain_span(sd));
|
|
atomic_inc(&sg->ref);
|
return sg;
|
}
|
|
static void init_overlap_sched_group(struct sched_domain *sd,
|
struct sched_group *sg)
|
{
|
struct cpumask *mask = sched_domains_tmpmask2;
|
struct sd_data *sdd = sd->private;
|
struct cpumask *sg_span;
|
int cpu;
|
|
build_balance_mask(sd, sg, mask);
|
cpu = cpumask_first_and(sched_group_span(sg), mask);
|
|
sg->sgc = *per_cpu_ptr(sdd->sgc, cpu);
|
if (atomic_inc_return(&sg->sgc->ref) == 1)
|
cpumask_copy(group_balance_mask(sg), mask);
|
else
|
WARN_ON_ONCE(!cpumask_equal(group_balance_mask(sg), mask));
|
|
/*
|
* Initialize sgc->capacity such that even if we mess up the
|
* domains and no possible iteration will get us here, we won't
|
* die on a /0 trap.
|
*/
|
sg_span = sched_group_span(sg);
|
sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span);
|
sg->sgc->min_capacity = SCHED_CAPACITY_SCALE;
|
sg->sgc->max_capacity = SCHED_CAPACITY_SCALE;
|
}
|
|
static int
|
build_overlap_sched_groups(struct sched_domain *sd, int cpu)
|
{
|
struct sched_group *first = NULL, *last = NULL, *sg;
|
const struct cpumask *span = sched_domain_span(sd);
|
struct cpumask *covered = sched_domains_tmpmask;
|
struct sd_data *sdd = sd->private;
|
struct sched_domain *sibling;
|
int i;
|
|
cpumask_clear(covered);
|
|
for_each_cpu_wrap(i, span, cpu) {
|
struct cpumask *sg_span;
|
|
if (cpumask_test_cpu(i, covered))
|
continue;
|
|
sibling = *per_cpu_ptr(sdd->sd, i);
|
|
/*
|
* Asymmetric node setups can result in situations where the
|
* domain tree is of unequal depth, make sure to skip domains
|
* that already cover the entire range.
|
*
|
* In that case build_sched_domains() will have terminated the
|
* iteration early and our sibling sd spans will be empty.
|
* Domains should always include the CPU they're built on, so
|
* check that.
|
*/
|
if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
|
continue;
|
|
sg = build_group_from_child_sched_domain(sibling, cpu);
|
if (!sg)
|
goto fail;
|
|
sg_span = sched_group_span(sg);
|
cpumask_or(covered, covered, sg_span);
|
|
init_overlap_sched_group(sd, sg);
|
|
if (!first)
|
first = sg;
|
if (last)
|
last->next = sg;
|
last = sg;
|
last->next = first;
|
}
|
sd->groups = first;
|
|
return 0;
|
|
fail:
|
free_sched_groups(first, 0);
|
|
return -ENOMEM;
|
}
|
|
|
/*
|
* Package topology (also see the load-balance blurb in fair.c)
|
*
|
* The scheduler builds a tree structure to represent a number of important
|
* topology features. By default (default_topology[]) these include:
|
*
|
* - Simultaneous multithreading (SMT)
|
* - Multi-Core Cache (MC)
|
* - Package (DIE)
|
*
|
* Where the last one more or less denotes everything up to a NUMA node.
|
*
|
* The tree consists of 3 primary data structures:
|
*
|
* sched_domain -> sched_group -> sched_group_capacity
|
* ^ ^ ^ ^
|
* `-' `-'
|
*
|
* The sched_domains are per-CPU and have a two way link (parent & child) and
|
* denote the ever growing mask of CPUs belonging to that level of topology.
|
*
|
* Each sched_domain has a circular (double) linked list of sched_group's, each
|
* denoting the domains of the level below (or individual CPUs in case of the
|
* first domain level). The sched_group linked by a sched_domain includes the
|
* CPU of that sched_domain [*].
|
*
|
* Take for instance a 2 threaded, 2 core, 2 cache cluster part:
|
*
|
* CPU 0 1 2 3 4 5 6 7
|
*
|
* DIE [ ]
|
* MC [ ] [ ]
|
* SMT [ ] [ ] [ ] [ ]
|
*
|
* - or -
|
*
|
* DIE 0-7 0-7 0-7 0-7 0-7 0-7 0-7 0-7
|
* MC 0-3 0-3 0-3 0-3 4-7 4-7 4-7 4-7
|
* SMT 0-1 0-1 2-3 2-3 4-5 4-5 6-7 6-7
|
*
|
* CPU 0 1 2 3 4 5 6 7
|
*
|
* One way to think about it is: sched_domain moves you up and down among these
|
* topology levels, while sched_group moves you sideways through it, at child
|
* domain granularity.
|
*
|
* sched_group_capacity ensures each unique sched_group has shared storage.
|
*
|
* There are two related construction problems, both require a CPU that
|
* uniquely identify each group (for a given domain):
|
*
|
* - The first is the balance_cpu (see should_we_balance() and the
|
* load-balance blub in fair.c); for each group we only want 1 CPU to
|
* continue balancing at a higher domain.
|
*
|
* - The second is the sched_group_capacity; we want all identical groups
|
* to share a single sched_group_capacity.
|
*
|
* Since these topologies are exclusive by construction. That is, its
|
* impossible for an SMT thread to belong to multiple cores, and cores to
|
* be part of multiple caches. There is a very clear and unique location
|
* for each CPU in the hierarchy.
|
*
|
* Therefore computing a unique CPU for each group is trivial (the iteration
|
* mask is redundant and set all 1s; all CPUs in a group will end up at _that_
|
* group), we can simply pick the first CPU in each group.
|
*
|
*
|
* [*] in other words, the first group of each domain is its child domain.
|
*/
|
|
static struct sched_group *get_group(int cpu, struct sd_data *sdd)
|
{
|
struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu);
|
struct sched_domain *child = sd->child;
|
struct sched_group *sg;
|
|
if (child)
|
cpu = cpumask_first(sched_domain_span(child));
|
|
sg = *per_cpu_ptr(sdd->sg, cpu);
|
sg->sgc = *per_cpu_ptr(sdd->sgc, cpu);
|
|
/* For claim_allocations: */
|
atomic_inc(&sg->ref);
|
atomic_inc(&sg->sgc->ref);
|
|
if (child) {
|
cpumask_copy(sched_group_span(sg), sched_domain_span(child));
|
cpumask_copy(group_balance_mask(sg), sched_group_span(sg));
|
} else {
|
cpumask_set_cpu(cpu, sched_group_span(sg));
|
cpumask_set_cpu(cpu, group_balance_mask(sg));
|
}
|
|
sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sched_group_span(sg));
|
sg->sgc->min_capacity = SCHED_CAPACITY_SCALE;
|
sg->sgc->max_capacity = SCHED_CAPACITY_SCALE;
|
|
return sg;
|
}
|
|
/*
|
* build_sched_groups will build a circular linked list of the groups
|
* covered by the given span, and will set each group's ->cpumask correctly,
|
* and ->cpu_capacity to 0.
|
*
|
* Assumes the sched_domain tree is fully constructed
|
*/
|
static int
|
build_sched_groups(struct sched_domain *sd, int cpu)
|
{
|
struct sched_group *first = NULL, *last = NULL;
|
struct sd_data *sdd = sd->private;
|
const struct cpumask *span = sched_domain_span(sd);
|
struct cpumask *covered;
|
int i;
|
|
lockdep_assert_held(&sched_domains_mutex);
|
covered = sched_domains_tmpmask;
|
|
cpumask_clear(covered);
|
|
for_each_cpu_wrap(i, span, cpu) {
|
struct sched_group *sg;
|
|
if (cpumask_test_cpu(i, covered))
|
continue;
|
|
sg = get_group(i, sdd);
|
|
cpumask_or(covered, covered, sched_group_span(sg));
|
|
if (!first)
|
first = sg;
|
if (last)
|
last->next = sg;
|
last = sg;
|
}
|
last->next = first;
|
sd->groups = first;
|
|
return 0;
|
}
|
|
/*
|
* Initialize sched groups cpu_capacity.
|
*
|
* cpu_capacity indicates the capacity of sched group, which is used while
|
* distributing the load between different sched groups in a sched domain.
|
* Typically cpu_capacity for all the groups in a sched domain will be same
|
* unless there are asymmetries in the topology. If there are asymmetries,
|
* group having more cpu_capacity will pickup more load compared to the
|
* group having less cpu_capacity.
|
*/
|
static void init_sched_groups_capacity(int cpu, struct sched_domain *sd)
|
{
|
struct sched_group *sg = sd->groups;
|
|
WARN_ON(!sg);
|
|
do {
|
int cpu, max_cpu = -1;
|
|
sg->group_weight = cpumask_weight(sched_group_span(sg));
|
|
if (!(sd->flags & SD_ASYM_PACKING))
|
goto next;
|
|
for_each_cpu(cpu, sched_group_span(sg)) {
|
if (max_cpu < 0)
|
max_cpu = cpu;
|
else if (sched_asym_prefer(cpu, max_cpu))
|
max_cpu = cpu;
|
}
|
sg->asym_prefer_cpu = max_cpu;
|
|
next:
|
sg = sg->next;
|
} while (sg != sd->groups);
|
|
if (cpu != group_balance_cpu(sg))
|
return;
|
|
update_group_capacity(sd, cpu);
|
}
|
|
/*
|
* Initializers for schedule domains
|
* Non-inlined to reduce accumulated stack pressure in build_sched_domains()
|
*/
|
|
static int default_relax_domain_level = -1;
|
int sched_domain_level_max;
|
|
static int __init setup_relax_domain_level(char *str)
|
{
|
if (kstrtoint(str, 0, &default_relax_domain_level))
|
pr_warn("Unable to set relax_domain_level\n");
|
|
return 1;
|
}
|
__setup("relax_domain_level=", setup_relax_domain_level);
|
|
static void set_domain_attribute(struct sched_domain *sd,
|
struct sched_domain_attr *attr)
|
{
|
int request;
|
|
if (!attr || attr->relax_domain_level < 0) {
|
if (default_relax_domain_level < 0)
|
return;
|
else
|
request = default_relax_domain_level;
|
} else
|
request = attr->relax_domain_level;
|
if (request < sd->level) {
|
/* Turn off idle balance on this domain: */
|
sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
|
} else {
|
/* Turn on idle balance on this domain: */
|
sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
|
}
|
}
|
|
static void __sdt_free(const struct cpumask *cpu_map);
|
static int __sdt_alloc(const struct cpumask *cpu_map);
|
|
static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
|
const struct cpumask *cpu_map)
|
{
|
switch (what) {
|
case sa_rootdomain:
|
if (!atomic_read(&d->rd->refcount))
|
free_rootdomain(&d->rd->rcu);
|
/* Fall through */
|
case sa_sd:
|
free_percpu(d->sd);
|
/* Fall through */
|
case sa_sd_storage:
|
__sdt_free(cpu_map);
|
/* Fall through */
|
case sa_none:
|
break;
|
}
|
}
|
|
static enum s_alloc
|
__visit_domain_allocation_hell(struct s_data *d, const struct cpumask *cpu_map)
|
{
|
memset(d, 0, sizeof(*d));
|
|
if (__sdt_alloc(cpu_map))
|
return sa_sd_storage;
|
d->sd = alloc_percpu(struct sched_domain *);
|
if (!d->sd)
|
return sa_sd_storage;
|
d->rd = alloc_rootdomain();
|
if (!d->rd)
|
return sa_sd;
|
|
return sa_rootdomain;
|
}
|
|
/*
|
* NULL the sd_data elements we've used to build the sched_domain and
|
* sched_group structure so that the subsequent __free_domain_allocs()
|
* will not free the data we're using.
|
*/
|
static void claim_allocations(int cpu, struct sched_domain *sd)
|
{
|
struct sd_data *sdd = sd->private;
|
|
WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd);
|
*per_cpu_ptr(sdd->sd, cpu) = NULL;
|
|
if (atomic_read(&(*per_cpu_ptr(sdd->sds, cpu))->ref))
|
*per_cpu_ptr(sdd->sds, cpu) = NULL;
|
|
if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref))
|
*per_cpu_ptr(sdd->sg, cpu) = NULL;
|
|
if (atomic_read(&(*per_cpu_ptr(sdd->sgc, cpu))->ref))
|
*per_cpu_ptr(sdd->sgc, cpu) = NULL;
|
}
|
|
#ifdef CONFIG_NUMA
|
enum numa_topology_type sched_numa_topology_type;
|
|
static int sched_domains_numa_levels;
|
static int sched_domains_curr_level;
|
|
int sched_max_numa_distance;
|
static int *sched_domains_numa_distance;
|
static struct cpumask ***sched_domains_numa_masks;
|
#endif
|
|
/*
|
* SD_flags allowed in topology descriptions.
|
*
|
* These flags are purely descriptive of the topology and do not prescribe
|
* behaviour. Behaviour is artificial and mapped in the below sd_init()
|
* function:
|
*
|
* SD_SHARE_CPUCAPACITY - describes SMT topologies
|
* SD_SHARE_PKG_RESOURCES - describes shared caches
|
* SD_NUMA - describes NUMA topologies
|
* SD_SHARE_POWERDOMAIN - describes shared power domain
|
*
|
* Odd one out, which beside describing the topology has a quirk also
|
* prescribes the desired behaviour that goes along with it:
|
*
|
* SD_ASYM_PACKING - describes SMT quirks
|
*/
|
#define TOPOLOGY_SD_FLAGS \
|
(SD_SHARE_CPUCAPACITY | \
|
SD_SHARE_PKG_RESOURCES | \
|
SD_NUMA | \
|
SD_ASYM_PACKING | \
|
SD_SHARE_POWERDOMAIN)
|
|
static struct sched_domain *
|
sd_init(struct sched_domain_topology_level *tl,
|
const struct cpumask *cpu_map,
|
struct sched_domain *child, int dflags, int cpu)
|
{
|
struct sd_data *sdd = &tl->data;
|
struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu);
|
int sd_id, sd_weight, sd_flags = 0;
|
|
#ifdef CONFIG_NUMA
|
/*
|
* Ugly hack to pass state to sd_numa_mask()...
|
*/
|
sched_domains_curr_level = tl->numa_level;
|
#endif
|
|
sd_weight = cpumask_weight(tl->mask(cpu));
|
|
if (tl->sd_flags)
|
sd_flags = (*tl->sd_flags)();
|
if (WARN_ONCE(sd_flags & ~TOPOLOGY_SD_FLAGS,
|
"wrong sd_flags in topology description\n"))
|
sd_flags &= TOPOLOGY_SD_FLAGS;
|
|
/* Apply detected topology flags */
|
sd_flags |= dflags;
|
|
*sd = (struct sched_domain){
|
.min_interval = sd_weight,
|
.max_interval = 2*sd_weight,
|
.busy_factor = 32,
|
.imbalance_pct = 125,
|
|
.cache_nice_tries = 0,
|
.busy_idx = 0,
|
.idle_idx = 0,
|
.newidle_idx = 0,
|
.wake_idx = 0,
|
.forkexec_idx = 0,
|
|
.flags = 1*SD_LOAD_BALANCE
|
| 1*SD_BALANCE_NEWIDLE
|
| 1*SD_BALANCE_EXEC
|
| 1*SD_BALANCE_FORK
|
| 0*SD_BALANCE_WAKE
|
| 1*SD_WAKE_AFFINE
|
| 0*SD_SHARE_CPUCAPACITY
|
| 0*SD_SHARE_PKG_RESOURCES
|
| 0*SD_SERIALIZE
|
| 1*SD_PREFER_SIBLING
|
| 0*SD_NUMA
|
| sd_flags
|
,
|
|
.last_balance = jiffies,
|
.balance_interval = sd_weight,
|
.smt_gain = 0,
|
.max_newidle_lb_cost = 0,
|
.next_decay_max_lb_cost = jiffies,
|
.child = child,
|
#ifdef CONFIG_SCHED_DEBUG
|
.name = tl->name,
|
#endif
|
};
|
|
cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu));
|
sd_id = cpumask_first(sched_domain_span(sd));
|
|
/*
|
* Convert topological properties into behaviour.
|
*/
|
|
if (sd->flags & SD_ASYM_CPUCAPACITY) {
|
struct sched_domain *t = sd;
|
|
/*
|
* Don't attempt to spread across CPUs of different capacities.
|
*/
|
if (sd->child)
|
sd->child->flags &= ~SD_PREFER_SIBLING;
|
|
for_each_lower_domain(t)
|
t->flags |= SD_BALANCE_WAKE;
|
}
|
|
if (sd->flags & SD_SHARE_CPUCAPACITY) {
|
sd->imbalance_pct = 110;
|
sd->smt_gain = 1178; /* ~15% */
|
|
} else if (sd->flags & SD_SHARE_PKG_RESOURCES) {
|
sd->imbalance_pct = 117;
|
sd->cache_nice_tries = 1;
|
sd->busy_idx = 2;
|
|
#ifdef CONFIG_NUMA
|
} else if (sd->flags & SD_NUMA) {
|
sd->cache_nice_tries = 2;
|
sd->busy_idx = 3;
|
sd->idle_idx = 2;
|
|
sd->flags &= ~SD_PREFER_SIBLING;
|
sd->flags |= SD_SERIALIZE;
|
if (sched_domains_numa_distance[tl->numa_level] > RECLAIM_DISTANCE) {
|
sd->flags &= ~(SD_BALANCE_EXEC |
|
SD_BALANCE_FORK |
|
SD_WAKE_AFFINE);
|
}
|
|
#endif
|
} else {
|
sd->cache_nice_tries = 1;
|
sd->busy_idx = 2;
|
sd->idle_idx = 1;
|
}
|
|
/*
|
* For all levels sharing cache; connect a sched_domain_shared
|
* instance.
|
*/
|
if (sd->flags & SD_SHARE_PKG_RESOURCES) {
|
sd->shared = *per_cpu_ptr(sdd->sds, sd_id);
|
atomic_inc(&sd->shared->ref);
|
atomic_set(&sd->shared->nr_busy_cpus, sd_weight);
|
}
|
|
sd->private = sdd;
|
|
return sd;
|
}
|
|
/*
|
* Topology list, bottom-up.
|
*/
|
static struct sched_domain_topology_level default_topology[] = {
|
#ifdef CONFIG_SCHED_SMT
|
{ cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
|
#endif
|
#ifdef CONFIG_SCHED_MC
|
{ cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
|
#endif
|
{ cpu_cpu_mask, SD_INIT_NAME(DIE) },
|
{ NULL, },
|
};
|
|
static struct sched_domain_topology_level *sched_domain_topology =
|
default_topology;
|
|
#define for_each_sd_topology(tl) \
|
for (tl = sched_domain_topology; tl->mask; tl++)
|
|
void set_sched_topology(struct sched_domain_topology_level *tl)
|
{
|
if (WARN_ON_ONCE(sched_smp_initialized))
|
return;
|
|
sched_domain_topology = tl;
|
}
|
|
#ifdef CONFIG_NUMA
|
|
static const struct cpumask *sd_numa_mask(int cpu)
|
{
|
return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)];
|
}
|
|
static void sched_numa_warn(const char *str)
|
{
|
static int done = false;
|
int i,j;
|
|
if (done)
|
return;
|
|
done = true;
|
|
printk(KERN_WARNING "ERROR: %s\n\n", str);
|
|
for (i = 0; i < nr_node_ids; i++) {
|
printk(KERN_WARNING " ");
|
for (j = 0; j < nr_node_ids; j++)
|
printk(KERN_CONT "%02d ", node_distance(i,j));
|
printk(KERN_CONT "\n");
|
}
|
printk(KERN_WARNING "\n");
|
}
|
|
bool find_numa_distance(int distance)
|
{
|
int i;
|
|
if (distance == node_distance(0, 0))
|
return true;
|
|
for (i = 0; i < sched_domains_numa_levels; i++) {
|
if (sched_domains_numa_distance[i] == distance)
|
return true;
|
}
|
|
return false;
|
}
|
|
/*
|
* A system can have three types of NUMA topology:
|
* NUMA_DIRECT: all nodes are directly connected, or not a NUMA system
|
* NUMA_GLUELESS_MESH: some nodes reachable through intermediary nodes
|
* NUMA_BACKPLANE: nodes can reach other nodes through a backplane
|
*
|
* The difference between a glueless mesh topology and a backplane
|
* topology lies in whether communication between not directly
|
* connected nodes goes through intermediary nodes (where programs
|
* could run), or through backplane controllers. This affects
|
* placement of programs.
|
*
|
* The type of topology can be discerned with the following tests:
|
* - If the maximum distance between any nodes is 1 hop, the system
|
* is directly connected.
|
* - If for two nodes A and B, located N > 1 hops away from each other,
|
* there is an intermediary node C, which is < N hops away from both
|
* nodes A and B, the system is a glueless mesh.
|
*/
|
static void init_numa_topology_type(void)
|
{
|
int a, b, c, n;
|
|
n = sched_max_numa_distance;
|
|
if (sched_domains_numa_levels <= 2) {
|
sched_numa_topology_type = NUMA_DIRECT;
|
return;
|
}
|
|
for_each_online_node(a) {
|
for_each_online_node(b) {
|
/* Find two nodes furthest removed from each other. */
|
if (node_distance(a, b) < n)
|
continue;
|
|
/* Is there an intermediary node between a and b? */
|
for_each_online_node(c) {
|
if (node_distance(a, c) < n &&
|
node_distance(b, c) < n) {
|
sched_numa_topology_type =
|
NUMA_GLUELESS_MESH;
|
return;
|
}
|
}
|
|
sched_numa_topology_type = NUMA_BACKPLANE;
|
return;
|
}
|
}
|
}
|
|
void sched_init_numa(void)
|
{
|
int next_distance, curr_distance = node_distance(0, 0);
|
struct sched_domain_topology_level *tl;
|
int level = 0;
|
int i, j, k;
|
|
sched_domains_numa_distance = kzalloc(sizeof(int) * (nr_node_ids + 1), GFP_KERNEL);
|
if (!sched_domains_numa_distance)
|
return;
|
|
/* Includes NUMA identity node at level 0. */
|
sched_domains_numa_distance[level++] = curr_distance;
|
sched_domains_numa_levels = level;
|
|
/*
|
* O(nr_nodes^2) deduplicating selection sort -- in order to find the
|
* unique distances in the node_distance() table.
|
*
|
* Assumes node_distance(0,j) includes all distances in
|
* node_distance(i,j) in order to avoid cubic time.
|
*/
|
next_distance = curr_distance;
|
for (i = 0; i < nr_node_ids; i++) {
|
for (j = 0; j < nr_node_ids; j++) {
|
for (k = 0; k < nr_node_ids; k++) {
|
int distance = node_distance(i, k);
|
|
if (distance > curr_distance &&
|
(distance < next_distance ||
|
next_distance == curr_distance))
|
next_distance = distance;
|
|
/*
|
* While not a strong assumption it would be nice to know
|
* about cases where if node A is connected to B, B is not
|
* equally connected to A.
|
*/
|
if (sched_debug() && node_distance(k, i) != distance)
|
sched_numa_warn("Node-distance not symmetric");
|
|
if (sched_debug() && i && !find_numa_distance(distance))
|
sched_numa_warn("Node-0 not representative");
|
}
|
if (next_distance != curr_distance) {
|
sched_domains_numa_distance[level++] = next_distance;
|
sched_domains_numa_levels = level;
|
curr_distance = next_distance;
|
} else break;
|
}
|
|
/*
|
* In case of sched_debug() we verify the above assumption.
|
*/
|
if (!sched_debug())
|
break;
|
}
|
|
/*
|
* 'level' contains the number of unique distances
|
*
|
* The sched_domains_numa_distance[] array includes the actual distance
|
* numbers.
|
*/
|
|
/*
|
* Here, we should temporarily reset sched_domains_numa_levels to 0.
|
* If it fails to allocate memory for array sched_domains_numa_masks[][],
|
* the array will contain less then 'level' members. This could be
|
* dangerous when we use it to iterate array sched_domains_numa_masks[][]
|
* in other functions.
|
*
|
* We reset it to 'level' at the end of this function.
|
*/
|
sched_domains_numa_levels = 0;
|
|
sched_domains_numa_masks = kzalloc(sizeof(void *) * level, GFP_KERNEL);
|
if (!sched_domains_numa_masks)
|
return;
|
|
/*
|
* Now for each level, construct a mask per node which contains all
|
* CPUs of nodes that are that many hops away from us.
|
*/
|
for (i = 0; i < level; i++) {
|
sched_domains_numa_masks[i] =
|
kzalloc(nr_node_ids * sizeof(void *), GFP_KERNEL);
|
if (!sched_domains_numa_masks[i])
|
return;
|
|
for (j = 0; j < nr_node_ids; j++) {
|
struct cpumask *mask = kzalloc(cpumask_size(), GFP_KERNEL);
|
if (!mask)
|
return;
|
|
sched_domains_numa_masks[i][j] = mask;
|
|
for_each_node(k) {
|
if (node_distance(j, k) > sched_domains_numa_distance[i])
|
continue;
|
|
cpumask_or(mask, mask, cpumask_of_node(k));
|
}
|
}
|
}
|
|
/* Compute default topology size */
|
for (i = 0; sched_domain_topology[i].mask; i++);
|
|
tl = kzalloc((i + level + 1) *
|
sizeof(struct sched_domain_topology_level), GFP_KERNEL);
|
if (!tl)
|
return;
|
|
/*
|
* Copy the default topology bits..
|
*/
|
for (i = 0; sched_domain_topology[i].mask; i++)
|
tl[i] = sched_domain_topology[i];
|
|
/*
|
* Add the NUMA identity distance, aka single NODE.
|
*/
|
tl[i++] = (struct sched_domain_topology_level){
|
.mask = sd_numa_mask,
|
.numa_level = 0,
|
SD_INIT_NAME(NODE)
|
};
|
|
/*
|
* .. and append 'j' levels of NUMA goodness.
|
*/
|
for (j = 1; j < level; i++, j++) {
|
tl[i] = (struct sched_domain_topology_level){
|
.mask = sd_numa_mask,
|
.sd_flags = cpu_numa_flags,
|
.flags = SDTL_OVERLAP,
|
.numa_level = j,
|
SD_INIT_NAME(NUMA)
|
};
|
}
|
|
sched_domain_topology = tl;
|
|
sched_domains_numa_levels = level;
|
sched_max_numa_distance = sched_domains_numa_distance[level - 1];
|
|
init_numa_topology_type();
|
}
|
|
void sched_domains_numa_masks_set(unsigned int cpu)
|
{
|
int node = cpu_to_node(cpu);
|
int i, j;
|
|
for (i = 0; i < sched_domains_numa_levels; i++) {
|
for (j = 0; j < nr_node_ids; j++) {
|
if (node_distance(j, node) <= sched_domains_numa_distance[i])
|
cpumask_set_cpu(cpu, sched_domains_numa_masks[i][j]);
|
}
|
}
|
}
|
|
void sched_domains_numa_masks_clear(unsigned int cpu)
|
{
|
int i, j;
|
|
for (i = 0; i < sched_domains_numa_levels; i++) {
|
for (j = 0; j < nr_node_ids; j++)
|
cpumask_clear_cpu(cpu, sched_domains_numa_masks[i][j]);
|
}
|
}
|
|
#endif /* CONFIG_NUMA */
|
|
static int __sdt_alloc(const struct cpumask *cpu_map)
|
{
|
struct sched_domain_topology_level *tl;
|
int j;
|
|
for_each_sd_topology(tl) {
|
struct sd_data *sdd = &tl->data;
|
|
sdd->sd = alloc_percpu(struct sched_domain *);
|
if (!sdd->sd)
|
return -ENOMEM;
|
|
sdd->sds = alloc_percpu(struct sched_domain_shared *);
|
if (!sdd->sds)
|
return -ENOMEM;
|
|
sdd->sg = alloc_percpu(struct sched_group *);
|
if (!sdd->sg)
|
return -ENOMEM;
|
|
sdd->sgc = alloc_percpu(struct sched_group_capacity *);
|
if (!sdd->sgc)
|
return -ENOMEM;
|
|
for_each_cpu(j, cpu_map) {
|
struct sched_domain *sd;
|
struct sched_domain_shared *sds;
|
struct sched_group *sg;
|
struct sched_group_capacity *sgc;
|
|
sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(),
|
GFP_KERNEL, cpu_to_node(j));
|
if (!sd)
|
return -ENOMEM;
|
|
*per_cpu_ptr(sdd->sd, j) = sd;
|
|
sds = kzalloc_node(sizeof(struct sched_domain_shared),
|
GFP_KERNEL, cpu_to_node(j));
|
if (!sds)
|
return -ENOMEM;
|
|
*per_cpu_ptr(sdd->sds, j) = sds;
|
|
sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
|
GFP_KERNEL, cpu_to_node(j));
|
if (!sg)
|
return -ENOMEM;
|
|
sg->next = sg;
|
|
*per_cpu_ptr(sdd->sg, j) = sg;
|
|
sgc = kzalloc_node(sizeof(struct sched_group_capacity) + cpumask_size(),
|
GFP_KERNEL, cpu_to_node(j));
|
if (!sgc)
|
return -ENOMEM;
|
|
#ifdef CONFIG_SCHED_DEBUG
|
sgc->id = j;
|
#endif
|
|
*per_cpu_ptr(sdd->sgc, j) = sgc;
|
}
|
}
|
|
return 0;
|
}
|
|
static void __sdt_free(const struct cpumask *cpu_map)
|
{
|
struct sched_domain_topology_level *tl;
|
int j;
|
|
for_each_sd_topology(tl) {
|
struct sd_data *sdd = &tl->data;
|
|
for_each_cpu(j, cpu_map) {
|
struct sched_domain *sd;
|
|
if (sdd->sd) {
|
sd = *per_cpu_ptr(sdd->sd, j);
|
if (sd && (sd->flags & SD_OVERLAP))
|
free_sched_groups(sd->groups, 0);
|
kfree(*per_cpu_ptr(sdd->sd, j));
|
}
|
|
if (sdd->sds)
|
kfree(*per_cpu_ptr(sdd->sds, j));
|
if (sdd->sg)
|
kfree(*per_cpu_ptr(sdd->sg, j));
|
if (sdd->sgc)
|
kfree(*per_cpu_ptr(sdd->sgc, j));
|
}
|
free_percpu(sdd->sd);
|
sdd->sd = NULL;
|
free_percpu(sdd->sds);
|
sdd->sds = NULL;
|
free_percpu(sdd->sg);
|
sdd->sg = NULL;
|
free_percpu(sdd->sgc);
|
sdd->sgc = NULL;
|
}
|
}
|
|
static struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
|
const struct cpumask *cpu_map, struct sched_domain_attr *attr,
|
struct sched_domain *child, int dflags, int cpu)
|
{
|
struct sched_domain *sd = sd_init(tl, cpu_map, child, dflags, cpu);
|
|
if (child) {
|
sd->level = child->level + 1;
|
sched_domain_level_max = max(sched_domain_level_max, sd->level);
|
child->parent = sd;
|
|
if (!cpumask_subset(sched_domain_span(child),
|
sched_domain_span(sd))) {
|
pr_err("BUG: arch topology borken\n");
|
#ifdef CONFIG_SCHED_DEBUG
|
pr_err(" the %s domain not a subset of the %s domain\n",
|
child->name, sd->name);
|
#endif
|
/* Fixup, ensure @sd has at least @child CPUs. */
|
cpumask_or(sched_domain_span(sd),
|
sched_domain_span(sd),
|
sched_domain_span(child));
|
}
|
|
}
|
set_domain_attribute(sd, attr);
|
|
return sd;
|
}
|
|
/*
|
* Find the sched_domain_topology_level where all CPU capacities are visible
|
* for all CPUs.
|
*/
|
static struct sched_domain_topology_level
|
*asym_cpu_capacity_level(const struct cpumask *cpu_map)
|
{
|
int i, j, asym_level = 0;
|
bool asym = false;
|
struct sched_domain_topology_level *tl, *asym_tl = NULL;
|
unsigned long cap;
|
|
/* Is there any asymmetry? */
|
cap = arch_scale_cpu_capacity(NULL, cpumask_first(cpu_map));
|
|
for_each_cpu(i, cpu_map) {
|
if (arch_scale_cpu_capacity(NULL, i) != cap) {
|
asym = true;
|
break;
|
}
|
}
|
|
if (!asym)
|
return NULL;
|
|
/*
|
* Examine topology from all CPU's point of views to detect the lowest
|
* sched_domain_topology_level where a highest capacity CPU is visible
|
* to everyone.
|
*/
|
for_each_cpu(i, cpu_map) {
|
unsigned long max_capacity = arch_scale_cpu_capacity(NULL, i);
|
int tl_id = 0;
|
|
for_each_sd_topology(tl) {
|
if (tl_id < asym_level)
|
goto next_level;
|
|
for_each_cpu_and(j, tl->mask(i), cpu_map) {
|
unsigned long capacity;
|
|
capacity = arch_scale_cpu_capacity(NULL, j);
|
|
if (capacity <= max_capacity)
|
continue;
|
|
max_capacity = capacity;
|
asym_level = tl_id;
|
asym_tl = tl;
|
}
|
next_level:
|
tl_id++;
|
}
|
}
|
|
return asym_tl;
|
}
|
|
|
/*
|
* Build sched domains for a given set of CPUs and attach the sched domains
|
* to the individual CPUs
|
*/
|
static int
|
build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *attr)
|
{
|
enum s_alloc alloc_state;
|
struct sched_domain *sd;
|
struct s_data d;
|
int i, ret = -ENOMEM;
|
struct sched_domain_topology_level *tl_asym;
|
bool has_asym = false;
|
|
alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
|
if (alloc_state != sa_rootdomain)
|
goto error;
|
|
tl_asym = asym_cpu_capacity_level(cpu_map);
|
|
/* Set up domains for CPUs specified by the cpu_map: */
|
for_each_cpu(i, cpu_map) {
|
struct sched_domain_topology_level *tl;
|
|
sd = NULL;
|
for_each_sd_topology(tl) {
|
int dflags = 0;
|
|
if (tl == tl_asym) {
|
dflags |= SD_ASYM_CPUCAPACITY;
|
has_asym = true;
|
}
|
|
sd = build_sched_domain(tl, cpu_map, attr, sd, dflags, i);
|
|
if (tl == sched_domain_topology)
|
*per_cpu_ptr(d.sd, i) = sd;
|
if (tl->flags & SDTL_OVERLAP)
|
sd->flags |= SD_OVERLAP;
|
if (cpumask_equal(cpu_map, sched_domain_span(sd)))
|
break;
|
}
|
}
|
|
/* Build the groups for the domains */
|
for_each_cpu(i, cpu_map) {
|
for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
|
sd->span_weight = cpumask_weight(sched_domain_span(sd));
|
if (sd->flags & SD_OVERLAP) {
|
if (build_overlap_sched_groups(sd, i))
|
goto error;
|
} else {
|
if (build_sched_groups(sd, i))
|
goto error;
|
}
|
}
|
}
|
|
/* Calculate CPU capacity for physical packages and nodes */
|
for (i = nr_cpumask_bits-1; i >= 0; i--) {
|
if (!cpumask_test_cpu(i, cpu_map))
|
continue;
|
|
for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
|
claim_allocations(i, sd);
|
init_sched_groups_capacity(i, sd);
|
}
|
}
|
|
/* Attach the domains */
|
rcu_read_lock();
|
for_each_cpu(i, cpu_map) {
|
sd = *per_cpu_ptr(d.sd, i);
|
cpu_attach_domain(sd, d.rd, i);
|
}
|
rcu_read_unlock();
|
|
if (has_asym)
|
static_branch_inc_cpuslocked(&sched_asym_cpucapacity);
|
|
ret = 0;
|
error:
|
__free_domain_allocs(&d, alloc_state, cpu_map);
|
|
return ret;
|
}
|
|
/* Current sched domains: */
|
static cpumask_var_t *doms_cur;
|
|
/* Number of sched domains in 'doms_cur': */
|
static int ndoms_cur;
|
|
/* Attribues of custom domains in 'doms_cur' */
|
static struct sched_domain_attr *dattr_cur;
|
|
/*
|
* Special case: If a kmalloc() of a doms_cur partition (array of
|
* cpumask) fails, then fallback to a single sched domain,
|
* as determined by the single cpumask fallback_doms.
|
*/
|
static cpumask_var_t fallback_doms;
|
|
/*
|
* arch_update_cpu_topology lets virtualized architectures update the
|
* CPU core maps. It is supposed to return 1 if the topology changed
|
* or 0 if it stayed the same.
|
*/
|
int __weak arch_update_cpu_topology(void)
|
{
|
return 0;
|
}
|
|
cpumask_var_t *alloc_sched_domains(unsigned int ndoms)
|
{
|
int i;
|
cpumask_var_t *doms;
|
|
doms = kmalloc_array(ndoms, sizeof(*doms), GFP_KERNEL);
|
if (!doms)
|
return NULL;
|
for (i = 0; i < ndoms; i++) {
|
if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) {
|
free_sched_domains(doms, i);
|
return NULL;
|
}
|
}
|
return doms;
|
}
|
|
void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms)
|
{
|
unsigned int i;
|
for (i = 0; i < ndoms; i++)
|
free_cpumask_var(doms[i]);
|
kfree(doms);
|
}
|
|
/*
|
* Set up scheduler domains and groups. Callers must hold the hotplug lock.
|
* For now this just excludes isolated CPUs, but could be used to
|
* exclude other special cases in the future.
|
*/
|
int sched_init_domains(const struct cpumask *cpu_map)
|
{
|
int err;
|
|
zalloc_cpumask_var(&sched_domains_tmpmask, GFP_KERNEL);
|
zalloc_cpumask_var(&sched_domains_tmpmask2, GFP_KERNEL);
|
zalloc_cpumask_var(&fallback_doms, GFP_KERNEL);
|
|
arch_update_cpu_topology();
|
ndoms_cur = 1;
|
doms_cur = alloc_sched_domains(ndoms_cur);
|
if (!doms_cur)
|
doms_cur = &fallback_doms;
|
cpumask_and(doms_cur[0], cpu_map, housekeeping_cpumask(HK_FLAG_DOMAIN));
|
err = build_sched_domains(doms_cur[0], NULL);
|
register_sched_domain_sysctl();
|
|
return err;
|
}
|
|
/*
|
* Detach sched domains from a group of CPUs specified in cpu_map
|
* These CPUs will now be attached to the NULL domain
|
*/
|
static void detach_destroy_domains(const struct cpumask *cpu_map)
|
{
|
unsigned int cpu = cpumask_any(cpu_map);
|
int i;
|
|
if (rcu_access_pointer(per_cpu(sd_asym_cpucapacity, cpu)))
|
static_branch_dec_cpuslocked(&sched_asym_cpucapacity);
|
|
rcu_read_lock();
|
for_each_cpu(i, cpu_map)
|
cpu_attach_domain(NULL, &def_root_domain, i);
|
rcu_read_unlock();
|
}
|
|
/* handle null as "default" */
|
static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
|
struct sched_domain_attr *new, int idx_new)
|
{
|
struct sched_domain_attr tmp;
|
|
/* Fast path: */
|
if (!new && !cur)
|
return 1;
|
|
tmp = SD_ATTR_INIT;
|
|
return !memcmp(cur ? (cur + idx_cur) : &tmp,
|
new ? (new + idx_new) : &tmp,
|
sizeof(struct sched_domain_attr));
|
}
|
|
/*
|
* Partition sched domains as specified by the 'ndoms_new'
|
* cpumasks in the array doms_new[] of cpumasks. This compares
|
* doms_new[] to the current sched domain partitioning, doms_cur[].
|
* It destroys each deleted domain and builds each new domain.
|
*
|
* 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'.
|
* The masks don't intersect (don't overlap.) We should setup one
|
* sched domain for each mask. CPUs not in any of the cpumasks will
|
* not be load balanced. If the same cpumask appears both in the
|
* current 'doms_cur' domains and in the new 'doms_new', we can leave
|
* it as it is.
|
*
|
* The passed in 'doms_new' should be allocated using
|
* alloc_sched_domains. This routine takes ownership of it and will
|
* free_sched_domains it when done with it. If the caller failed the
|
* alloc call, then it can pass in doms_new == NULL && ndoms_new == 1,
|
* and partition_sched_domains() will fallback to the single partition
|
* 'fallback_doms', it also forces the domains to be rebuilt.
|
*
|
* If doms_new == NULL it will be replaced with cpu_online_mask.
|
* ndoms_new == 0 is a special case for destroying existing domains,
|
* and it will not create the default domain.
|
*
|
* Call with hotplug lock held
|
*/
|
void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
|
struct sched_domain_attr *dattr_new)
|
{
|
bool __maybe_unused has_eas = false;
|
int i, j, n;
|
int new_topology;
|
|
mutex_lock(&sched_domains_mutex);
|
|
/* Always unregister in case we don't destroy any domains: */
|
unregister_sched_domain_sysctl();
|
|
/* Let the architecture update CPU core mappings: */
|
new_topology = arch_update_cpu_topology();
|
|
if (!doms_new) {
|
WARN_ON_ONCE(dattr_new);
|
n = 0;
|
doms_new = alloc_sched_domains(1);
|
if (doms_new) {
|
n = 1;
|
cpumask_and(doms_new[0], cpu_active_mask,
|
housekeeping_cpumask(HK_FLAG_DOMAIN));
|
}
|
} else {
|
n = ndoms_new;
|
}
|
|
/* Destroy deleted domains: */
|
for (i = 0; i < ndoms_cur; i++) {
|
for (j = 0; j < n && !new_topology; j++) {
|
if (cpumask_equal(doms_cur[i], doms_new[j]) &&
|
dattrs_equal(dattr_cur, i, dattr_new, j))
|
goto match1;
|
}
|
/* No match - a current sched domain not in new doms_new[] */
|
detach_destroy_domains(doms_cur[i]);
|
match1:
|
;
|
}
|
|
n = ndoms_cur;
|
if (!doms_new) {
|
n = 0;
|
doms_new = &fallback_doms;
|
cpumask_and(doms_new[0], cpu_active_mask,
|
housekeeping_cpumask(HK_FLAG_DOMAIN));
|
}
|
|
/* Build new domains: */
|
for (i = 0; i < ndoms_new; i++) {
|
for (j = 0; j < n && !new_topology; j++) {
|
if (cpumask_equal(doms_new[i], doms_cur[j]) &&
|
dattrs_equal(dattr_new, i, dattr_cur, j))
|
goto match2;
|
}
|
/* No match - add a new doms_new */
|
build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL);
|
match2:
|
;
|
}
|
|
#ifdef CONFIG_ENERGY_MODEL
|
/* Build perf. domains: */
|
for (i = 0; i < ndoms_new; i++) {
|
for (j = 0; j < n; j++) {
|
if (cpumask_equal(doms_new[i], doms_cur[j]) &&
|
cpu_rq(cpumask_first(doms_cur[j]))->rd->pd) {
|
has_eas = true;
|
goto match3;
|
}
|
}
|
/* No match - add perf. domains for a new rd */
|
has_eas |= build_perf_domains(doms_new[i]);
|
match3:
|
;
|
}
|
sched_energy_set(has_eas);
|
#endif
|
|
/* Remember the new sched domains: */
|
if (doms_cur != &fallback_doms)
|
free_sched_domains(doms_cur, ndoms_cur);
|
|
kfree(dattr_cur);
|
doms_cur = doms_new;
|
dattr_cur = dattr_new;
|
ndoms_cur = ndoms_new;
|
|
register_sched_domain_sysctl();
|
|
mutex_unlock(&sched_domains_mutex);
|
}
|
