forked from luck/tmp_suning_uos_patched
c20e1ea4b6
Signed-off-by: Lauro Ramos Venancio <lvenanci@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: lwang@redhat.com Cc: riel@redhat.com Link: http://lkml.kernel.org/r/1492717903-5195-4-git-send-email-lvenanci@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
1691 lines
40 KiB
C
1691 lines
40 KiB
C
/*
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* Scheduler topology setup/handling methods
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*/
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#include <linux/sched.h>
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#include <linux/mutex.h>
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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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#ifdef CONFIG_SCHED_DEBUG
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static __read_mostly int sched_debug_enabled;
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static int __init sched_debug_setup(char *str)
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{
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sched_debug_enabled = 1;
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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)
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{
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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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{
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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"
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" 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 "
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"CPU%d\n", cpu);
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}
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if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) {
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printk(KERN_ERR "ERROR: domain->groups does not contain"
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" 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_cpus(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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}
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if (!(sd->flags & SD_OVERLAP) &&
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cpumask_intersects(groupmask, sched_group_cpus(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_cpus(group));
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printk(KERN_CONT " %*pbl",
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cpumask_pr_args(sched_group_cpus(group)));
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if ((sd->flags & SD_OVERLAP) && !cpumask_full(sched_group_mask(group))) {
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printk(KERN_CONT " (mask: %*pbl)",
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cpumask_pr_args(sched_group_mask(group)));
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}
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if (group->sgc->capacity != SCHED_CAPACITY_SCALE) {
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printk(KERN_CONT " (cpu_capacity: %lu)",
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group->sgc->capacity);
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}
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if (group == sd->groups && sd->child &&
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!cpumask_equal(sched_domain_span(sd->child),
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sched_group_cpus(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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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 "
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"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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}
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printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
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for (;;) {
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if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask))
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break;
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level++;
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sd = sd->parent;
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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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{
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return false;
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}
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#endif /* CONFIG_SCHED_DEBUG */
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static int sd_degenerate(struct sched_domain *sd)
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{
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if (cpumask_weight(sched_domain_span(sd)) == 1)
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return 1;
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/* Following flags need at least 2 groups */
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if (sd->flags & (SD_LOAD_BALANCE |
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SD_BALANCE_NEWIDLE |
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SD_BALANCE_FORK |
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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)
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return 0;
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}
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/* Following flags don't use groups */
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if (sd->flags & (SD_WAKE_AFFINE))
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return 0;
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return 1;
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}
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static int
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sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
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{
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unsigned long cflags = sd->flags, pflags = parent->flags;
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if (sd_degenerate(parent))
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return 1;
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if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent)))
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return 0;
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/* Flags needing groups don't count if only 1 group in parent */
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if (parent->groups == parent->groups->next) {
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pflags &= ~(SD_LOAD_BALANCE |
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SD_BALANCE_NEWIDLE |
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SD_BALANCE_FORK |
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SD_BALANCE_EXEC |
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SD_ASYM_CPUCAPACITY |
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SD_SHARE_CPUCAPACITY |
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SD_SHARE_PKG_RESOURCES |
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SD_PREFER_SIBLING |
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SD_SHARE_POWERDOMAIN);
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if (nr_node_ids == 1)
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pflags &= ~SD_SERIALIZE;
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}
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if (~cflags & pflags)
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return 0;
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return 1;
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}
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static void free_rootdomain(struct rcu_head *rcu)
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{
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struct root_domain *rd = container_of(rcu, struct root_domain, rcu);
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cpupri_cleanup(&rd->cpupri);
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cpudl_cleanup(&rd->cpudl);
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free_cpumask_var(rd->dlo_mask);
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free_cpumask_var(rd->rto_mask);
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free_cpumask_var(rd->online);
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free_cpumask_var(rd->span);
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kfree(rd);
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}
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void rq_attach_root(struct rq *rq, struct root_domain *rd)
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{
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struct root_domain *old_rd = NULL;
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unsigned long flags;
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raw_spin_lock_irqsave(&rq->lock, flags);
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if (rq->rd) {
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old_rd = rq->rd;
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if (cpumask_test_cpu(rq->cpu, old_rd->online))
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set_rq_offline(rq);
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cpumask_clear_cpu(rq->cpu, old_rd->span);
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/*
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* If we dont want to free the old_rd yet then
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* set old_rd to NULL to skip the freeing later
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* in this function:
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*/
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if (!atomic_dec_and_test(&old_rd->refcount))
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old_rd = NULL;
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}
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atomic_inc(&rd->refcount);
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rq->rd = rd;
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cpumask_set_cpu(rq->cpu, rd->span);
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if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
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set_rq_online(rq);
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raw_spin_unlock_irqrestore(&rq->lock, flags);
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if (old_rd)
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call_rcu_sched(&old_rd->rcu, free_rootdomain);
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}
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static int init_rootdomain(struct root_domain *rd)
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{
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memset(rd, 0, sizeof(*rd));
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if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL))
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goto out;
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if (!zalloc_cpumask_var(&rd->online, GFP_KERNEL))
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goto free_span;
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if (!zalloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
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goto free_online;
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if (!zalloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
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goto free_dlo_mask;
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init_dl_bw(&rd->dl_bw);
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if (cpudl_init(&rd->cpudl) != 0)
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goto free_rto_mask;
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if (cpupri_init(&rd->cpupri) != 0)
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goto free_cpudl;
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return 0;
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free_cpudl:
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cpudl_cleanup(&rd->cpudl);
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free_rto_mask:
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free_cpumask_var(rd->rto_mask);
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free_dlo_mask:
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free_cpumask_var(rd->dlo_mask);
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free_online:
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free_cpumask_var(rd->online);
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free_span:
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free_cpumask_var(rd->span);
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out:
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return -ENOMEM;
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}
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/*
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* By default the system creates a single root-domain with all CPUs as
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* members (mimicking the global state we have today).
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*/
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struct root_domain def_root_domain;
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void init_defrootdomain(void)
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{
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init_rootdomain(&def_root_domain);
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atomic_set(&def_root_domain.refcount, 1);
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}
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static struct root_domain *alloc_rootdomain(void)
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{
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struct root_domain *rd;
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rd = kmalloc(sizeof(*rd), GFP_KERNEL);
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if (!rd)
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return NULL;
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if (init_rootdomain(rd) != 0) {
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kfree(rd);
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return NULL;
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}
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return rd;
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}
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static void free_sched_groups(struct sched_group *sg, int free_sgc)
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{
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struct sched_group *tmp, *first;
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if (!sg)
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return;
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first = sg;
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do {
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tmp = sg->next;
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if (free_sgc && atomic_dec_and_test(&sg->sgc->ref))
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kfree(sg->sgc);
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kfree(sg);
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sg = tmp;
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} while (sg != first);
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}
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static void destroy_sched_domain(struct sched_domain *sd)
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{
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/*
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* If its an overlapping domain it has private groups, iterate and
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* nuke them all.
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*/
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if (sd->flags & SD_OVERLAP) {
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free_sched_groups(sd->groups, 1);
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} else if (atomic_dec_and_test(&sd->groups->ref)) {
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kfree(sd->groups->sgc);
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kfree(sd->groups);
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}
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if (sd->shared && atomic_dec_and_test(&sd->shared->ref))
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kfree(sd->shared);
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kfree(sd);
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}
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static void destroy_sched_domains_rcu(struct rcu_head *rcu)
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{
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struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu);
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while (sd) {
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struct sched_domain *parent = sd->parent;
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destroy_sched_domain(sd);
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sd = parent;
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}
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}
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static void destroy_sched_domains(struct sched_domain *sd)
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{
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if (sd)
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call_rcu(&sd->rcu, destroy_sched_domains_rcu);
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}
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/*
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* Keep a special pointer to the highest sched_domain that has
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* SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this
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* allows us to avoid some pointer chasing select_idle_sibling().
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*
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* Also keep a unique ID per domain (we use the first CPU number in
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* the cpumask of the domain), this allows us to quickly tell if
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* two CPUs are in the same cache domain, see cpus_share_cache().
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*/
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DEFINE_PER_CPU(struct sched_domain *, sd_llc);
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DEFINE_PER_CPU(int, sd_llc_size);
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DEFINE_PER_CPU(int, sd_llc_id);
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DEFINE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
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DEFINE_PER_CPU(struct sched_domain *, sd_numa);
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DEFINE_PER_CPU(struct sched_domain *, sd_asym);
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static void update_top_cache_domain(int cpu)
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{
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struct sched_domain_shared *sds = NULL;
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struct sched_domain *sd;
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int id = cpu;
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int size = 1;
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sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES);
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if (sd) {
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id = cpumask_first(sched_domain_span(sd));
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size = cpumask_weight(sched_domain_span(sd));
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sds = sd->shared;
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}
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rcu_assign_pointer(per_cpu(sd_llc, cpu), sd);
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per_cpu(sd_llc_size, cpu) = size;
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per_cpu(sd_llc_id, cpu) = id;
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rcu_assign_pointer(per_cpu(sd_llc_shared, cpu), sds);
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sd = lowest_flag_domain(cpu, SD_NUMA);
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rcu_assign_pointer(per_cpu(sd_numa, cpu), sd);
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sd = highest_flag_domain(cpu, SD_ASYM_PACKING);
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rcu_assign_pointer(per_cpu(sd_asym, cpu), sd);
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}
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/*
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* Attach the domain 'sd' to 'cpu' as its base domain. Callers must
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* hold the hotplug lock.
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*/
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static void
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cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
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{
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struct rq *rq = cpu_rq(cpu);
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struct sched_domain *tmp;
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/* Remove the sched domains which do not contribute to scheduling. */
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for (tmp = sd; tmp; ) {
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struct sched_domain *parent = tmp->parent;
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if (!parent)
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break;
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if (sd_parent_degenerate(tmp, parent)) {
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tmp->parent = parent->parent;
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if (parent->parent)
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parent->parent->child = tmp;
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/*
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* Transfer SD_PREFER_SIBLING down in case of a
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* degenerate parent; the spans match for this
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* so the property transfers.
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*/
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if (parent->flags & SD_PREFER_SIBLING)
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tmp->flags |= SD_PREFER_SIBLING;
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destroy_sched_domain(parent);
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} else
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tmp = tmp->parent;
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}
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if (sd && sd_degenerate(sd)) {
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tmp = sd;
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sd = sd->parent;
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destroy_sched_domain(tmp);
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if (sd)
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sd->child = NULL;
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}
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sched_domain_debug(sd, cpu);
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rq_attach_root(rq, rd);
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tmp = rq->sd;
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rcu_assign_pointer(rq->sd, sd);
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destroy_sched_domains(tmp);
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update_top_cache_domain(cpu);
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}
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/* Setup the mask of CPUs configured for isolated domains */
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static int __init isolated_cpu_setup(char *str)
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{
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int ret;
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alloc_bootmem_cpumask_var(&cpu_isolated_map);
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ret = cpulist_parse(str, cpu_isolated_map);
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if (ret) {
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pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
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return 0;
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}
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return 1;
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}
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__setup("isolcpus=", isolated_cpu_setup);
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struct s_data {
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struct sched_domain ** __percpu sd;
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struct root_domain *rd;
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};
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enum s_alloc {
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sa_rootdomain,
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sa_sd,
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sa_sd_storage,
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sa_none,
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};
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|
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/*
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* Build an iteration mask that can exclude certain CPUs from the upwards
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* domain traversal.
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*/
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static void build_group_mask(struct sched_domain *sd, struct sched_group *sg)
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{
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const struct cpumask *sg_span = sched_group_cpus(sg);
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struct sd_data *sdd = sd->private;
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struct sched_domain *sibling;
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int i;
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for_each_cpu(i, sg_span) {
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sibling = *per_cpu_ptr(sdd->sd, i);
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if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
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continue;
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cpumask_set_cpu(i, sched_group_mask(sg));
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}
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}
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|
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/*
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* Return the canonical balance CPU for this group, this is the first CPU
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* of this group that's also in the iteration mask.
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*/
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int group_balance_cpu(struct sched_group *sg)
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{
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return cpumask_first_and(sched_group_cpus(sg), sched_group_mask(sg));
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}
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|
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static struct sched_group *
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build_group_from_child_sched_domain(struct sched_domain *sd, int cpu)
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{
|
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struct sched_group *sg;
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struct cpumask *sg_span;
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|
|
|
sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
|
|
GFP_KERNEL, cpu_to_node(cpu));
|
|
|
|
if (!sg)
|
|
return NULL;
|
|
|
|
sg_span = sched_group_cpus(sg);
|
|
if (sd->child)
|
|
cpumask_copy(sg_span, sched_domain_span(sd->child));
|
|
else
|
|
cpumask_copy(sg_span, sched_domain_span(sd));
|
|
|
|
return sg;
|
|
}
|
|
|
|
static void init_overlap_sched_group(struct sched_domain *sd,
|
|
struct sched_group *sg, int cpu)
|
|
{
|
|
struct sd_data *sdd = sd->private;
|
|
struct cpumask *sg_span;
|
|
|
|
sg->sgc = *per_cpu_ptr(sdd->sgc, cpu);
|
|
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_span = sched_group_cpus(sg);
|
|
sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span);
|
|
sg->sgc->min_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_cpus(sg);
|
|
cpumask_or(covered, covered, sg_span);
|
|
|
|
init_overlap_sched_group(sd, sg, i);
|
|
|
|
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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
}
|
|
|
|
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.
|
|
*/
|
|
|
|
/*
|
|
* 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];
|
|
|
|
/*
|
|
* .. and append 'j' levels of NUMA goodness.
|
|
*/
|
|
for (j = 0; 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;
|
|
|
|
*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;
|
|
}
|
|
}
|
|
|
|
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 cpu)
|
|
{
|
|
struct sched_domain *sd = sd_init(tl, cpu_map, child, 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;
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
struct rq *rq = NULL;
|
|
int i, ret = -ENOMEM;
|
|
|
|
alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
|
|
if (alloc_state != sa_rootdomain)
|
|
goto error;
|
|
|
|
/* 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) {
|
|
sd = build_sched_domain(tl, cpu_map, attr, sd, i);
|
|
if (tl == sched_domain_topology)
|
|
*per_cpu_ptr(d.sd, i) = sd;
|
|
if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_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) {
|
|
rq = cpu_rq(i);
|
|
sd = *per_cpu_ptr(d.sd, i);
|
|
|
|
/* Use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing: */
|
|
if (rq->cpu_capacity_orig > READ_ONCE(d.rd->max_cpu_capacity))
|
|
WRITE_ONCE(d.rd->max_cpu_capacity, rq->cpu_capacity_orig);
|
|
|
|
cpu_attach_domain(sd, d.rd, i);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (rq && sched_debug_enabled) {
|
|
pr_info("span: %*pbl (max cpu_capacity = %lu)\n",
|
|
cpumask_pr_args(cpu_map), rq->rd->max_cpu_capacity);
|
|
}
|
|
|
|
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.
|
|
*/
|
|
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(sizeof(*doms) * ndoms, 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 init_sched_domains(const struct cpumask *cpu_map)
|
|
{
|
|
int err;
|
|
|
|
arch_update_cpu_topology();
|
|
ndoms_cur = 1;
|
|
doms_cur = alloc_sched_domains(ndoms_cur);
|
|
if (!doms_cur)
|
|
doms_cur = &fallback_doms;
|
|
cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map);
|
|
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)
|
|
{
|
|
int i;
|
|
|
|
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)
|
|
{
|
|
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();
|
|
|
|
n = doms_new ? ndoms_new : 0;
|
|
|
|
/* 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 == NULL) {
|
|
n = 0;
|
|
doms_new = &fallback_doms;
|
|
cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map);
|
|
WARN_ON_ONCE(dattr_new);
|
|
}
|
|
|
|
/* 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:
|
|
;
|
|
}
|
|
|
|
/* 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);
|
|
}
|
|
|