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-rw-r--r--kernel/sched.c269
1 files changed, 245 insertions, 24 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index ed90be46fb3..afe76ec2e7f 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -44,6 +44,7 @@
#include <linux/vmalloc.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
+#include <linux/pid_namespace.h>
#include <linux/smp.h>
#include <linux/threads.h>
#include <linux/timer.h>
@@ -51,6 +52,7 @@
#include <linux/cpu.h>
#include <linux/cpuset.h>
#include <linux/percpu.h>
+#include <linux/cpu_acct.h>
#include <linux/kthread.h>
#include <linux/seq_file.h>
#include <linux/sysctl.h>
@@ -153,10 +155,15 @@ struct rt_prio_array {
#ifdef CONFIG_FAIR_GROUP_SCHED
+#include <linux/cgroup.h>
+
struct cfs_rq;
/* task group related information */
struct task_group {
+#ifdef CONFIG_FAIR_CGROUP_SCHED
+ struct cgroup_subsys_state css;
+#endif
/* schedulable entities of this group on each cpu */
struct sched_entity **se;
/* runqueue "owned" by this group on each cpu */
@@ -197,6 +204,9 @@ static inline struct task_group *task_group(struct task_struct *p)
#ifdef CONFIG_FAIR_USER_SCHED
tg = p->user->tg;
+#elif defined(CONFIG_FAIR_CGROUP_SCHED)
+ tg = container_of(task_subsys_state(p, cpu_cgroup_subsys_id),
+ struct task_group, css);
#else
tg = &init_task_group;
#endif
@@ -1875,7 +1885,7 @@ asmlinkage void schedule_tail(struct task_struct *prev)
preempt_enable();
#endif
if (current->set_child_tid)
- put_user(current->pid, current->set_child_tid);
+ put_user(task_pid_vnr(current), current->set_child_tid);
}
/*
@@ -3307,9 +3317,13 @@ void account_user_time(struct task_struct *p, cputime_t cputime)
{
struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
cputime64_t tmp;
+ struct rq *rq = this_rq();
p->utime = cputime_add(p->utime, cputime);
+ if (p != rq->idle)
+ cpuacct_charge(p, cputime);
+
/* Add user time to cpustat. */
tmp = cputime_to_cputime64(cputime);
if (TASK_NICE(p) > 0)
@@ -3374,9 +3388,10 @@ void account_system_time(struct task_struct *p, int hardirq_offset,
cpustat->irq = cputime64_add(cpustat->irq, tmp);
else if (softirq_count())
cpustat->softirq = cputime64_add(cpustat->softirq, tmp);
- else if (p != rq->idle)
+ else if (p != rq->idle) {
cpustat->system = cputime64_add(cpustat->system, tmp);
- else if (atomic_read(&rq->nr_iowait) > 0)
+ cpuacct_charge(p, cputime);
+ } else if (atomic_read(&rq->nr_iowait) > 0)
cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
else
cpustat->idle = cputime64_add(cpustat->idle, tmp);
@@ -3412,8 +3427,10 @@ void account_steal_time(struct task_struct *p, cputime_t steal)
cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
else
cpustat->idle = cputime64_add(cpustat->idle, tmp);
- } else
+ } else {
cpustat->steal = cputime64_add(cpustat->steal, tmp);
+ cpuacct_charge(p, -tmp);
+ }
}
/*
@@ -3493,7 +3510,7 @@ EXPORT_SYMBOL(sub_preempt_count);
static noinline void __schedule_bug(struct task_struct *prev)
{
printk(KERN_ERR "BUG: scheduling while atomic: %s/0x%08x/%d\n",
- prev->comm, preempt_count(), prev->pid);
+ prev->comm, preempt_count(), task_pid_nr(prev));
debug_show_held_locks(prev);
if (irqs_disabled())
print_irqtrace_events(prev);
@@ -4159,7 +4176,7 @@ struct task_struct *idle_task(int cpu)
*/
static struct task_struct *find_process_by_pid(pid_t pid)
{
- return pid ? find_task_by_pid(pid) : current;
+ return pid ? find_task_by_vpid(pid) : current;
}
/* Actually do priority change: must hold rq lock. */
@@ -4462,8 +4479,21 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask)
cpus_allowed = cpuset_cpus_allowed(p);
cpus_and(new_mask, new_mask, cpus_allowed);
+ again:
retval = set_cpus_allowed(p, new_mask);
+ if (!retval) {
+ cpus_allowed = cpuset_cpus_allowed(p);
+ if (!cpus_subset(new_mask, cpus_allowed)) {
+ /*
+ * We must have raced with a concurrent cpuset
+ * update. Just reset the cpus_allowed to the
+ * cpuset's cpus_allowed
+ */
+ new_mask = cpus_allowed;
+ goto again;
+ }
+ }
out_unlock:
put_task_struct(p);
mutex_unlock(&sched_hotcpu_mutex);
@@ -4843,7 +4873,8 @@ static void show_task(struct task_struct *p)
free = (unsigned long)n - (unsigned long)end_of_stack(p);
}
#endif
- printk(KERN_CONT "%5lu %5d %6d\n", free, p->pid, p->parent->pid);
+ printk(KERN_CONT "%5lu %5d %6d\n", free,
+ task_pid_nr(p), task_pid_nr(p->parent));
if (state != TASK_RUNNING)
show_stack(p, NULL);
@@ -5137,8 +5168,16 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
/* No more Mr. Nice Guy. */
if (dest_cpu == NR_CPUS) {
+ cpumask_t cpus_allowed = cpuset_cpus_allowed_locked(p);
+ /*
+ * Try to stay on the same cpuset, where the
+ * current cpuset may be a subset of all cpus.
+ * The cpuset_cpus_allowed_locked() variant of
+ * cpuset_cpus_allowed() will not block. It must be
+ * called within calls to cpuset_lock/cpuset_unlock.
+ */
rq = task_rq_lock(p, &flags);
- cpus_setall(p->cpus_allowed);
+ p->cpus_allowed = cpus_allowed;
dest_cpu = any_online_cpu(p->cpus_allowed);
task_rq_unlock(rq, &flags);
@@ -5150,7 +5189,7 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
if (p->mm && printk_ratelimit())
printk(KERN_INFO "process %d (%s) no "
"longer affine to cpu%d\n",
- p->pid, p->comm, dead_cpu);
+ task_pid_nr(p), p->comm, dead_cpu);
}
} while (!__migrate_task_irq(p, dead_cpu, dest_cpu));
}
@@ -5257,7 +5296,7 @@ static void migrate_dead(unsigned int dead_cpu, struct task_struct *p)
struct rq *rq = cpu_rq(dead_cpu);
/* Must be exiting, otherwise would be on tasklist. */
- BUG_ON(p->exit_state != EXIT_ZOMBIE && p->exit_state != EXIT_DEAD);
+ BUG_ON(!p->exit_state);
/* Cannot have done final schedule yet: would have vanished. */
BUG_ON(p->state == TASK_DEAD);
@@ -5504,6 +5543,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
case CPU_DEAD:
case CPU_DEAD_FROZEN:
+ cpuset_lock(); /* around calls to cpuset_cpus_allowed_lock() */
migrate_live_tasks(cpu);
rq = cpu_rq(cpu);
kthread_stop(rq->migration_thread);
@@ -5517,6 +5557,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
rq->idle->sched_class = &idle_sched_class;
migrate_dead_tasks(cpu);
spin_unlock_irq(&rq->lock);
+ cpuset_unlock();
migrate_nr_uninterruptible(rq);
BUG_ON(rq->nr_running != 0);
@@ -6367,26 +6408,31 @@ error:
return -ENOMEM;
#endif
}
+
+static cpumask_t *doms_cur; /* current sched domains */
+static int ndoms_cur; /* number of sched domains in 'doms_cur' */
+
+/*
+ * Special case: If a kmalloc of a doms_cur partition (array of
+ * cpumask_t) fails, then fallback to a single sched domain,
+ * as determined by the single cpumask_t fallback_doms.
+ */
+static cpumask_t fallback_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.
*/
static int arch_init_sched_domains(const cpumask_t *cpu_map)
{
- cpumask_t cpu_default_map;
- int err;
-
- /*
- * Setup mask for cpus without special case scheduling requirements.
- * For now this just excludes isolated cpus, but could be used to
- * exclude other special cases in the future.
- */
- cpus_andnot(cpu_default_map, *cpu_map, cpu_isolated_map);
-
- err = build_sched_domains(&cpu_default_map);
-
+ ndoms_cur = 1;
+ doms_cur = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
+ if (!doms_cur)
+ doms_cur = &fallback_doms;
+ cpus_andnot(*doms_cur, *cpu_map, cpu_isolated_map);
register_sched_domain_sysctl();
-
- return err;
+ return build_sched_domains(doms_cur);
}
static void arch_destroy_sched_domains(const cpumask_t *cpu_map)
@@ -6410,6 +6456,68 @@ static void detach_destroy_domains(const cpumask_t *cpu_map)
arch_destroy_sched_domains(cpu_map);
}
+/*
+ * 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_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 kmalloc'd. This routine takes
+ * ownership of it and will kfree it when done with it. If the caller
+ * failed the kmalloc call, then it can pass in doms_new == NULL,
+ * and partition_sched_domains() will fallback to the single partition
+ * 'fallback_doms'.
+ *
+ * Call with hotplug lock held
+ */
+void partition_sched_domains(int ndoms_new, cpumask_t *doms_new)
+{
+ int i, j;
+
+ if (doms_new == NULL) {
+ ndoms_new = 1;
+ doms_new = &fallback_doms;
+ cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map);
+ }
+
+ /* Destroy deleted domains */
+ for (i = 0; i < ndoms_cur; i++) {
+ for (j = 0; j < ndoms_new; j++) {
+ if (cpus_equal(doms_cur[i], doms_new[j]))
+ goto match1;
+ }
+ /* no match - a current sched domain not in new doms_new[] */
+ detach_destroy_domains(doms_cur + i);
+match1:
+ ;
+ }
+
+ /* Build new domains */
+ for (i = 0; i < ndoms_new; i++) {
+ for (j = 0; j < ndoms_cur; j++) {
+ if (cpus_equal(doms_new[i], doms_cur[j]))
+ goto match2;
+ }
+ /* no match - add a new doms_new */
+ build_sched_domains(doms_new + i);
+match2:
+ ;
+ }
+
+ /* Remember the new sched domains */
+ if (doms_cur != &fallback_doms)
+ kfree(doms_cur);
+ doms_cur = doms_new;
+ ndoms_cur = ndoms_new;
+}
+
#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
static int arch_reinit_sched_domains(void)
{
@@ -6991,3 +7099,116 @@ unsigned long sched_group_shares(struct task_group *tg)
}
#endif /* CONFIG_FAIR_GROUP_SCHED */
+
+#ifdef CONFIG_FAIR_CGROUP_SCHED
+
+/* return corresponding task_group object of a cgroup */
+static inline struct task_group *cgroup_tg(struct cgroup *cont)
+{
+ return container_of(cgroup_subsys_state(cont, cpu_cgroup_subsys_id),
+ struct task_group, css);
+}
+
+static struct cgroup_subsys_state *
+cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+ struct task_group *tg;
+
+ if (!cont->parent) {
+ /* This is early initialization for the top cgroup */
+ init_task_group.css.cgroup = cont;
+ return &init_task_group.css;
+ }
+
+ /* we support only 1-level deep hierarchical scheduler atm */
+ if (cont->parent->parent)
+ return ERR_PTR(-EINVAL);
+
+ tg = sched_create_group();
+ if (IS_ERR(tg))
+ return ERR_PTR(-ENOMEM);
+
+ /* Bind the cgroup to task_group object we just created */
+ tg->css.cgroup = cont;
+
+ return &tg->css;
+}
+
+static void cpu_cgroup_destroy(struct cgroup_subsys *ss,
+ struct cgroup *cont)
+{
+ struct task_group *tg = cgroup_tg(cont);
+
+ sched_destroy_group(tg);
+}
+
+static int cpu_cgroup_can_attach(struct cgroup_subsys *ss,
+ struct cgroup *cont, struct task_struct *tsk)
+{
+ /* We don't support RT-tasks being in separate groups */
+ if (tsk->sched_class != &fair_sched_class)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void
+cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cont,
+ struct cgroup *old_cont, struct task_struct *tsk)
+{
+ sched_move_task(tsk);
+}
+
+static ssize_t cpu_shares_write(struct cgroup *cont, struct cftype *cftype,
+ struct file *file, const char __user *userbuf,
+ size_t nbytes, loff_t *ppos)
+{
+ unsigned long shareval;
+ struct task_group *tg = cgroup_tg(cont);
+ char buffer[2*sizeof(unsigned long) + 1];
+ int rc;
+
+ if (nbytes > 2*sizeof(unsigned long)) /* safety check */
+ return -E2BIG;
+
+ if (copy_from_user(buffer, userbuf, nbytes))
+ return -EFAULT;
+
+ buffer[nbytes] = 0; /* nul-terminate */
+ shareval = simple_strtoul(buffer, NULL, 10);
+
+ rc = sched_group_set_shares(tg, shareval);
+
+ return (rc < 0 ? rc : nbytes);
+}
+
+static u64 cpu_shares_read_uint(struct cgroup *cont, struct cftype *cft)
+{
+ struct task_group *tg = cgroup_tg(cont);
+
+ return (u64) tg->shares;
+}
+
+static struct cftype cpu_shares = {
+ .name = "shares",
+ .read_uint = cpu_shares_read_uint,
+ .write = cpu_shares_write,
+};
+
+static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+ return cgroup_add_file(cont, ss, &cpu_shares);
+}
+
+struct cgroup_subsys cpu_cgroup_subsys = {
+ .name = "cpu",
+ .create = cpu_cgroup_create,
+ .destroy = cpu_cgroup_destroy,
+ .can_attach = cpu_cgroup_can_attach,
+ .attach = cpu_cgroup_attach,
+ .populate = cpu_cgroup_populate,
+ .subsys_id = cpu_cgroup_subsys_id,
+ .early_init = 1,
+};
+
+#endif /* CONFIG_FAIR_CGROUP_SCHED */