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-rw-r--r--kernel/sched.c155
1 files changed, 129 insertions, 26 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 98dcdf272db3..59ff6b140edb 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -854,6 +854,12 @@ iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
struct rq_iterator *iterator);
#endif
+#ifdef CONFIG_CGROUP_CPUACCT
+static void cpuacct_charge(struct task_struct *tsk, u64 cputime);
+#else
+static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
+#endif
+
#include "sched_stats.h"
#include "sched_idletask.c"
#include "sched_fair.c"
@@ -7221,38 +7227,12 @@ static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft)
return (u64) tg->shares;
}
-static u64 cpu_usage_read(struct cgroup *cgrp, struct cftype *cft)
-{
- struct task_group *tg = cgroup_tg(cgrp);
- unsigned long flags;
- u64 res = 0;
- int i;
-
- for_each_possible_cpu(i) {
- /*
- * Lock to prevent races with updating 64-bit counters
- * on 32-bit arches.
- */
- spin_lock_irqsave(&cpu_rq(i)->lock, flags);
- res += tg->se[i]->sum_exec_runtime;
- spin_unlock_irqrestore(&cpu_rq(i)->lock, flags);
- }
- /* Convert from ns to ms */
- do_div(res, NSEC_PER_MSEC);
-
- return res;
-}
-
static struct cftype cpu_files[] = {
{
.name = "shares",
.read_uint = cpu_shares_read_uint,
.write_uint = cpu_shares_write_uint,
},
- {
- .name = "usage",
- .read_uint = cpu_usage_read,
- },
};
static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)
@@ -7272,3 +7252,126 @@ struct cgroup_subsys cpu_cgroup_subsys = {
};
#endif /* CONFIG_FAIR_CGROUP_SCHED */
+
+#ifdef CONFIG_CGROUP_CPUACCT
+
+/*
+ * CPU accounting code for task groups.
+ *
+ * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
+ * (balbir@in.ibm.com).
+ */
+
+/* track cpu usage of a group of tasks */
+struct cpuacct {
+ struct cgroup_subsys_state css;
+ /* cpuusage holds pointer to a u64-type object on every cpu */
+ u64 *cpuusage;
+};
+
+struct cgroup_subsys cpuacct_subsys;
+
+/* return cpu accounting group corresponding to this container */
+static inline struct cpuacct *cgroup_ca(struct cgroup *cont)
+{
+ return container_of(cgroup_subsys_state(cont, cpuacct_subsys_id),
+ struct cpuacct, css);
+}
+
+/* return cpu accounting group to which this task belongs */
+static inline struct cpuacct *task_ca(struct task_struct *tsk)
+{
+ return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
+ struct cpuacct, css);
+}
+
+/* create a new cpu accounting group */
+static struct cgroup_subsys_state *cpuacct_create(
+ struct cgroup_subsys *ss, struct cgroup *cont)
+{
+ struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
+
+ if (!ca)
+ return ERR_PTR(-ENOMEM);
+
+ ca->cpuusage = alloc_percpu(u64);
+ if (!ca->cpuusage) {
+ kfree(ca);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return &ca->css;
+}
+
+/* destroy an existing cpu accounting group */
+static void cpuacct_destroy(struct cgroup_subsys *ss,
+ struct cgroup *cont)
+{
+ struct cpuacct *ca = cgroup_ca(cont);
+
+ free_percpu(ca->cpuusage);
+ kfree(ca);
+}
+
+/* return total cpu usage (in nanoseconds) of a group */
+static u64 cpuusage_read(struct cgroup *cont, struct cftype *cft)
+{
+ struct cpuacct *ca = cgroup_ca(cont);
+ u64 totalcpuusage = 0;
+ int i;
+
+ for_each_possible_cpu(i) {
+ u64 *cpuusage = percpu_ptr(ca->cpuusage, i);
+
+ /*
+ * Take rq->lock to make 64-bit addition safe on 32-bit
+ * platforms.
+ */
+ spin_lock_irq(&cpu_rq(i)->lock);
+ totalcpuusage += *cpuusage;
+ spin_unlock_irq(&cpu_rq(i)->lock);
+ }
+
+ return totalcpuusage;
+}
+
+static struct cftype files[] = {
+ {
+ .name = "usage",
+ .read_uint = cpuusage_read,
+ },
+};
+
+static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+ return cgroup_add_files(cont, ss, files, ARRAY_SIZE(files));
+}
+
+/*
+ * charge this task's execution time to its accounting group.
+ *
+ * called with rq->lock held.
+ */
+static void cpuacct_charge(struct task_struct *tsk, u64 cputime)
+{
+ struct cpuacct *ca;
+
+ if (!cpuacct_subsys.active)
+ return;
+
+ ca = task_ca(tsk);
+ if (ca) {
+ u64 *cpuusage = percpu_ptr(ca->cpuusage, task_cpu(tsk));
+
+ *cpuusage += cputime;
+ }
+}
+
+struct cgroup_subsys cpuacct_subsys = {
+ .name = "cpuacct",
+ .create = cpuacct_create,
+ .destroy = cpuacct_destroy,
+ .populate = cpuacct_populate,
+ .subsys_id = cpuacct_subsys_id,
+};
+#endif /* CONFIG_CGROUP_CPUACCT */