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authorIngo Molnar <mingo@kernel.org>2017-02-01 13:10:18 +0100
committerIngo Molnar <mingo@kernel.org>2017-02-07 10:58:12 +0100
commitf2cb13609d5397cdd747f3ed6fb651233851717d (patch)
tree0714785a7b04430b41346653178afc7b9a7bca70 /kernel/sched
parent004172bdad644327dc7a6543186b9d7b529ee944 (diff)
sched/topology: Split out scheduler topology code from core.c into topology.c
Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched')
-rw-r--r--kernel/sched/Makefile2
-rw-r--r--kernel/sched/core.c1659
-rw-r--r--kernel/sched/sched.h23
-rw-r--r--kernel/sched/topology.c1658
4 files changed, 1684 insertions, 1658 deletions
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 5e59b832ae2b..130ce8ac725b 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -18,7 +18,7 @@ endif
obj-y += core.o loadavg.o clock.o cputime.o
obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
obj-y += wait.o swait.o completion.o idle.o
-obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o
+obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o topology.o
obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
obj-$(CONFIG_SCHEDSTATS) += stats.o
obj-$(CONFIG_SCHED_DEBUG) += debug.o
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 1cea6c61fb01..e4aa470ed454 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -31,7 +31,6 @@
#define CREATE_TRACE_POINTS
#include <trace/events/sched.h>
-DEFINE_MUTEX(sched_domains_mutex);
DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
/*
@@ -5446,7 +5445,7 @@ out:
#ifdef CONFIG_SMP
-static bool sched_smp_initialized __read_mostly;
+bool sched_smp_initialized __read_mostly;
#ifdef CONFIG_NUMA_BALANCING
/* Migrate current task p to target_cpu */
@@ -5643,7 +5642,7 @@ static void migrate_tasks(struct rq *dead_rq)
}
#endif /* CONFIG_HOTPLUG_CPU */
-static void set_rq_online(struct rq *rq)
+void set_rq_online(struct rq *rq)
{
if (!rq->online) {
const struct sched_class *class;
@@ -5658,7 +5657,7 @@ static void set_rq_online(struct rq *rq)
}
}
-static void set_rq_offline(struct rq *rq)
+void set_rq_offline(struct rq *rq)
{
if (rq->online) {
const struct sched_class *class;
@@ -5680,1658 +5679,6 @@ static void set_cpu_rq_start_time(unsigned int cpu)
rq->age_stamp = sched_clock_cpu(cpu);
}
-/* Protected by sched_domains_mutex: */
-static cpumask_var_t sched_domains_tmpmask;
-
-#ifdef CONFIG_SCHED_DEBUG
-
-static __read_mostly int sched_debug_enabled;
-
-static int __init sched_debug_setup(char *str)
-{
- sched_debug_enabled = 1;
-
- return 0;
-}
-early_param("sched_debug", sched_debug_setup);
-
-static inline bool sched_debug(void)
-{
- return sched_debug_enabled;
-}
-
-static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
- struct cpumask *groupmask)
-{
- struct sched_group *group = sd->groups;
-
- cpumask_clear(groupmask);
-
- printk(KERN_DEBUG "%*s domain %d: ", level, "", level);
-
- if (!(sd->flags & SD_LOAD_BALANCE)) {
- printk("does not load-balance\n");
- if (sd->parent)
- printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain"
- " has parent");
- return -1;
- }
-
- printk(KERN_CONT "span %*pbl level %s\n",
- cpumask_pr_args(sched_domain_span(sd)), sd->name);
-
- if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) {
- printk(KERN_ERR "ERROR: domain->span does not contain "
- "CPU%d\n", cpu);
- }
- if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) {
- printk(KERN_ERR "ERROR: domain->groups does not contain"
- " CPU%d\n", cpu);
- }
-
- printk(KERN_DEBUG "%*s groups:", level + 1, "");
- do {
- if (!group) {
- printk("\n");
- printk(KERN_ERR "ERROR: group is NULL\n");
- break;
- }
-
- if (!cpumask_weight(sched_group_cpus(group))) {
- printk(KERN_CONT "\n");
- printk(KERN_ERR "ERROR: empty group\n");
- break;
- }
-
- if (!(sd->flags & SD_OVERLAP) &&
- cpumask_intersects(groupmask, sched_group_cpus(group))) {
- printk(KERN_CONT "\n");
- printk(KERN_ERR "ERROR: repeated CPUs\n");
- break;
- }
-
- cpumask_or(groupmask, groupmask, sched_group_cpus(group));
-
- printk(KERN_CONT " %*pbl",
- cpumask_pr_args(sched_group_cpus(group)));
- if (group->sgc->capacity != SCHED_CAPACITY_SCALE) {
- printk(KERN_CONT " (cpu_capacity = %lu)",
- group->sgc->capacity);
- }
-
- group = group->next;
- } while (group != sd->groups);
- printk(KERN_CONT "\n");
-
- if (!cpumask_equal(sched_domain_span(sd), groupmask))
- printk(KERN_ERR "ERROR: groups don't span domain->span\n");
-
- if (sd->parent &&
- !cpumask_subset(groupmask, sched_domain_span(sd->parent)))
- printk(KERN_ERR "ERROR: parent span is not a superset "
- "of domain->span\n");
- return 0;
-}
-
-static void sched_domain_debug(struct sched_domain *sd, int cpu)
-{
- int level = 0;
-
- if (!sched_debug_enabled)
- return;
-
- if (!sd) {
- printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
- return;
- }
-
- printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
-
- for (;;) {
- if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask))
- break;
- level++;
- sd = sd->parent;
- if (!sd)
- break;
- }
-}
-#else /* !CONFIG_SCHED_DEBUG */
-
-# define sched_debug_enabled 0
-# define sched_domain_debug(sd, cpu) do { } while (0)
-static inline bool sched_debug(void)
-{
- return false;
-}
-#endif /* CONFIG_SCHED_DEBUG */
-
-static int sd_degenerate(struct sched_domain *sd)
-{
- if (cpumask_weight(sched_domain_span(sd)) == 1)
- return 1;
-
- /* Following flags need at least 2 groups */
- if (sd->flags & (SD_LOAD_BALANCE |
- SD_BALANCE_NEWIDLE |
- SD_BALANCE_FORK |
- SD_BALANCE_EXEC |
- SD_SHARE_CPUCAPACITY |
- SD_ASYM_CPUCAPACITY |
- SD_SHARE_PKG_RESOURCES |
- SD_SHARE_POWERDOMAIN)) {
- if (sd->groups != sd->groups->next)
- return 0;
- }
-
- /* Following flags don't use groups */
- 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 |
- SD_BALANCE_NEWIDLE |
- SD_BALANCE_FORK |
- SD_BALANCE_EXEC |
- SD_ASYM_CPUCAPACITY |
- 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;
-}
-
-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);
- kfree(rd);
-}
-
-static 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);
-}
-
-static int init_rootdomain(struct root_domain *rd)
-{
- memset(rd, 0, sizeof(*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;
-
- 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;
- 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;
-
-static 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 = kmalloc(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);
-
- kfree(sg);
- sg = tmp;
- } while (sg != first);
-}
-
-static void destroy_sched_domain(struct sched_domain *sd)
-{
- /*
- * If its an overlapping domain it has private groups, iterate and
- * nuke them all.
- */
- if (sd->flags & SD_OVERLAP) {
- free_sched_groups(sd->groups, 1);
- } else if (atomic_dec_and_test(&sd->groups->ref)) {
- kfree(sd->groups->sgc);
- kfree(sd->groups);
- }
- 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);
-
-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, 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);
- destroy_sched_domains(tmp);
-
- update_top_cache_domain(cpu);
-}
-
-/* Setup the mask of CPUs configured for isolated domains */
-static int __init isolated_cpu_setup(char *str)
-{
- int ret;
-
- alloc_bootmem_cpumask_var(&cpu_isolated_map);
- ret = cpulist_parse(str, cpu_isolated_map);
- if (ret) {
- pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
- return 0;
- }
- return 1;
-}
-__setup("isolcpus=", isolated_cpu_setup);
-
-struct s_data {
- struct sched_domain ** __percpu sd;
- struct root_domain *rd;
-};
-
-enum s_alloc {
- sa_rootdomain,
- sa_sd,
- sa_sd_storage,
- sa_none,
-};
-
-/*
- * Build an iteration mask that can exclude certain CPUs from the upwards
- * domain traversal.
- *
- * 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.
- */
-static void build_group_mask(struct sched_domain *sd, struct sched_group *sg)
-{
- const struct cpumask *span = sched_domain_span(sd);
- struct sd_data *sdd = sd->private;
- struct sched_domain *sibling;
- int i;
-
- for_each_cpu(i, span) {
- sibling = *per_cpu_ptr(sdd->sd, i);
- if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
- continue;
-
- cpumask_set_cpu(i, sched_group_mask(sg));
- }
-}
-
-/*
- * Return the canonical balance CPU for this group, this is the first CPU
- * of this group that's also in the iteration mask.
- */
-int group_balance_cpu(struct sched_group *sg)
-{
- return cpumask_first_and(sched_group_cpus(sg), sched_group_mask(sg));
-}
-
-static int
-build_overlap_sched_groups(struct sched_domain *sd, int cpu)
-{
- struct sched_group *first = NULL, *last = NULL, *groups = 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(i, span) {
- struct cpumask *sg_span;
-
- if (cpumask_test_cpu(i, covered))
- continue;
-
- sibling = *per_cpu_ptr(sdd->sd, i);
-
- /* See the comment near build_group_mask(). */
- if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
- continue;
-
- sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
- GFP_KERNEL, cpu_to_node(cpu));
-
- if (!sg)
- goto fail;
-
- sg_span = sched_group_cpus(sg);
- if (sibling->child)
- cpumask_copy(sg_span, sched_domain_span(sibling->child));
- else
- cpumask_set_cpu(i, sg_span);
-
- cpumask_or(covered, covered, sg_span);
-
- sg->sgc = *per_cpu_ptr(sdd->sgc, i);
- if (atomic_inc_return(&sg->sgc->ref) == 1)
- build_group_mask(sd, sg);
-
- /*
- * 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->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span);
- sg->sgc->min_capacity = SCHED_CAPACITY_SCALE;
-
- /*
- * Make sure the first group of this domain contains the
- * canonical balance CPU. Otherwise the sched_domain iteration
- * breaks. See update_sg_lb_stats().
- */
- if ((!groups && cpumask_test_cpu(cpu, sg_span)) ||
- group_balance_cpu(sg) == cpu)
- groups = sg;
-
- if (!first)
- first = sg;
- if (last)
- last->next = sg;
- last = sg;
- last->next = first;
- }
- sd->groups = groups;
-
- return 0;
-
-fail:
- free_sched_groups(first, 0);
-
- return -ENOMEM;
-}
-
-static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
-{
- struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu);
- struct sched_domain *child = sd->child;
-
- if (child)
- cpu = cpumask_first(sched_domain_span(child));
-
- if (sg) {
- *sg = *per_cpu_ptr(sdd->sg, cpu);
- (*sg)->sgc = *per_cpu_ptr(sdd->sgc, cpu);
-
- /* For claim_allocations: */
- atomic_set(&(*sg)->sgc->ref, 1);
- }
-
- return cpu;
-}
-
-/*
- * 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;
-
- get_group(cpu, sdd, &sd->groups);
- atomic_inc(&sd->groups->ref);
-
- if (cpu != cpumask_first(span))
- return 0;
-
- lockdep_assert_held(&sched_domains_mutex);
- covered = sched_domains_tmpmask;
-
- cpumask_clear(covered);
-
- for_each_cpu(i, span) {
- struct sched_group *sg;
- int group, j;
-
- if (cpumask_test_cpu(i, covered))
- continue;
-
- group = get_group(i, sdd, &sg);
- cpumask_setall(sched_group_mask(sg));
-
- for_each_cpu(j, span) {
- if (get_group(j, sdd, NULL) != group)
- continue;
-
- cpumask_set_cpu(j, covered);
- cpumask_set_cpu(j, sched_group_cpus(sg));
- }
-
- if (!first)
- first = sg;
- if (last)
- last->next = sg;
- last = sg;
- }
- last->next = 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_cpus(sg));
-
- if (!(sd->flags & SD_ASYM_PACKING))
- goto next;
-
- for_each_cpu(cpu, sched_group_cpus(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
-static int sched_domains_numa_levels;
-enum numa_topology_type sched_numa_topology_type;
-static int *sched_domains_numa_distance;
-int sched_max_numa_distance;
-static struct cpumask ***sched_domains_numa_masks;
-static int sched_domains_curr_level;
-#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
- * SD_ASYM_CPUCAPACITY - describes mixed capacity topologies
- *
- * 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_ASYM_CPUCAPACITY | \
- 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 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;
-
- *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
- | 0*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;
-
- for_each_lower_domain(t)
- t->flags |= SD_BALANCE_WAKE;
- }
-
- if (sd->flags & SD_SHARE_CPUCAPACITY) {
- sd->flags |= SD_PREFER_SIBLING;
- 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_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->flags |= SD_PREFER_SIBLING;
- 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 <= 1) {
- 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;
- }
- }
-}
-
-static 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, GFP_KERNEL);
- if (!sched_domains_numa_distance)
- return;
-
- /*
- * 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;
- }
-
- if (!level)
- return;
-
- /*
- * 'level' contains the number of unique distances, excluding the
- * identity distance node_distance(i,i).
- *
- * The sched_domains_numa_distance[] array includes the actual distance
- * numbers.
- */
-
- /*