cgroups: add cpu_relax() calls in css_tryget() and cgroup_clear_css_refs()

[safe/jmp/linux-2.6] / kernel / sched_stats.h

diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index b8c1569..8ab0cef 100644 (file)
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -9,7 +9,7 @@
 static int show_schedstat(struct seq_file *seq, void *v)
 {
        int cpu;
-       int mask_len = NR_CPUS/32 * 9;
+       int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9;
        char *mask_str = kmalloc(mask_len, GFP_KERNEL);
 
        if (mask_str == NULL)
@@ -31,7 +31,7 @@ static int show_schedstat(struct seq_file *seq, void *v)
                    rq->yld_act_empty, rq->yld_exp_empty, rq->yld_count,
                    rq->sched_switch, rq->sched_count, rq->sched_goidle,
                    rq->ttwu_count, rq->ttwu_local,
-                   rq->rq_sched_info.cpu_time,
+                   rq->rq_cpu_time,
                    rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
 
                seq_printf(seq, "\n");
@@ -42,7 +42,8 @@ static int show_schedstat(struct seq_file *seq, void *v)
                for_each_domain(cpu, sd) {
                        enum cpu_idle_type itype;
 
-                       cpumask_scnprintf(mask_str, mask_len, sd->span);
+                       cpumask_scnprintf(mask_str, mask_len,
+                                         sched_domain_span(sd));
                        seq_printf(seq, "domain%d %s", dcount++, mask_str);
                        for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
                                        itype++) {
@@ -90,13 +91,20 @@ static int schedstat_open(struct inode *inode, struct file *file)
        return res;
 }
 
-const struct file_operations proc_schedstat_operations = {
+static const struct file_operations proc_schedstat_operations = {
        .open    = schedstat_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = single_release,
 };
 
+static int __init proc_schedstat_init(void)
+{
+       proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
+       return 0;
+}
+module_init(proc_schedstat_init);
+
 /*
  * Expects runqueue lock to be held for atomicity of update
  */
@@ -116,7 +124,7 @@ static inline void
 rq_sched_info_depart(struct rq *rq, unsigned long long delta)
 {
        if (rq)
-               rq->rq_sched_info.cpu_time += delta;
+               rq->rq_cpu_time += delta;
 }
 
 static inline void
@@ -229,7 +237,6 @@ static inline void sched_info_depart(struct task_struct *t)
        unsigned long long delta = task_rq(t)->clock -
                                        t->sched_info.last_arrival;
 
-       t->sched_info.cpu_time += delta;
        rq_sched_info_depart(task_rq(t), delta);
 
        if (t->state == TASK_RUNNING)
@@ -289,18 +296,19 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next)
 static inline void account_group_user_time(struct task_struct *tsk,
                                           cputime_t cputime)
 {
+       struct task_cputime *times;
        struct signal_struct *sig;
 
-       sig = tsk->signal;
-       if (unlikely(!sig))
+       /* tsk == current, ensure it is safe to use ->signal */
+       if (unlikely(tsk->exit_state))
                return;
-       if (sig->cputime.totals) {
-               struct task_cputime *times;
 
-               times = per_cpu_ptr(sig->cputime.totals, get_cpu());
-               times->utime = cputime_add(times->utime, cputime);
-               put_cpu_no_resched();
-       }
+       sig = tsk->signal;
+       times = &sig->cputime.totals;
+
+       spin_lock(&times->lock);
+       times->utime = cputime_add(times->utime, cputime);
+       spin_unlock(&times->lock);
 }
 
 /**
@@ -316,18 +324,19 @@ static inline void account_group_user_time(struct task_struct *tsk,
 static inline void account_group_system_time(struct task_struct *tsk,
                                             cputime_t cputime)
 {
+       struct task_cputime *times;
        struct signal_struct *sig;
 
-       sig = tsk->signal;
-       if (unlikely(!sig))
+       /* tsk == current, ensure it is safe to use ->signal */
+       if (unlikely(tsk->exit_state))
                return;
-       if (sig->cputime.totals) {
-               struct task_cputime *times;
 
-               times = per_cpu_ptr(sig->cputime.totals, get_cpu());
-               times->stime = cputime_add(times->stime, cputime);
-               put_cpu_no_resched();
-       }
+       sig = tsk->signal;
+       times = &sig->cputime.totals;
+
+       spin_lock(&times->lock);
+       times->stime = cputime_add(times->stime, cputime);
+       spin_unlock(&times->lock);
 }
 
 /**
@@ -343,16 +352,18 @@ static inline void account_group_system_time(struct task_struct *tsk,
 static inline void account_group_exec_runtime(struct task_struct *tsk,
                                              unsigned long long ns)
 {
+       struct task_cputime *times;
        struct signal_struct *sig;
 
        sig = tsk->signal;
+       /* see __exit_signal()->task_rq_unlock_wait() */
+       barrier();
        if (unlikely(!sig))
                return;
-       if (sig->cputime.totals) {
-               struct task_cputime *times;
 
-               times = per_cpu_ptr(sig->cputime.totals, get_cpu());
-               times->sum_exec_runtime += ns;
-               put_cpu_no_resched();
-       }
+       times = &sig->cputime.totals;
+
+       spin_lock(&times->lock);
+       times->sum_exec_runtime += ns;
+       spin_unlock(&times->lock);
 }