Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched

* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
  sched: fix style in kernel/sched.c
  sched: fix style of swap() macro in kernel/sched_fair.c
  sched: report CPU usage in CFS cgroup directories
  sched: move rcu_head to task_group struct
  sched: fix incorrect assumption that cpu 0 exists
  sched: keep utime/stime monotonic
  sched: make kernel/sched.c:account_guest_time() static

fs/proc/array.c

@@ -358,7 +358,8 @@ static cputime_t task_utime(struct task_struct *p)
 	}
 	utime = (clock_t)temp;
 
-	return clock_t_to_cputime(utime);
+	p->prev_utime = max(p->prev_utime, clock_t_to_cputime(utime));
+	return p->prev_utime;
 }
 
 static cputime_t task_stime(struct task_struct *p)

include/linux/sched.h

@@ -1009,6 +1009,7 @@ struct task_struct {
 	unsigned int rt_priority;
 	cputime_t utime, stime, utimescaled, stimescaled;
 	cputime_t gtime;
+	cputime_t prev_utime;
 	unsigned long nvcsw, nivcsw; /* context switch counts */
 	struct timespec start_time; 		/* monotonic time */
 	struct timespec real_start_time;	/* boot based time */

kernel/fork.c

@@ -1056,6 +1056,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	p->gtime = cputime_zero;
 	p->utimescaled = cputime_zero;
 	p->stimescaled = cputime_zero;
+	p->prev_utime = cputime_zero;
 
 #ifdef CONFIG_TASK_XACCT
 	p->rchar = 0;		/* I/O counter: bytes read */

kernel/sched.c

@@ -172,6 +172,7 @@ struct task_group {
 	unsigned long shares;
 	/* spinlock to serialize modification to shares */
 	spinlock_t lock;
+	struct rcu_head rcu;
 };
 
 /* Default task group's sched entity on each cpu */
@@ -258,7 +259,6 @@ struct cfs_rq {
 	 */
 	struct list_head leaf_cfs_rq_list; /* Better name : task_cfs_rq_list? */
 	struct task_group *tg;    /* group that "owns" this runqueue */
-	struct rcu_head rcu;
 #endif
 };
 
@@ -3355,7 +3355,7 @@ void account_user_time(struct task_struct *p, cputime_t cputime)
  * @p: the process that the cpu time gets accounted to
  * @cputime: the cpu time spent in virtual machine since the last update
  */
-void account_guest_time(struct task_struct *p, cputime_t cputime)
+static void account_guest_time(struct task_struct *p, cputime_t cputime)
 {
 	cputime64_t tmp;
 	struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
@@ -5365,7 +5365,7 @@ static struct ctl_table sd_ctl_dir[] = {
 		.procname	= "sched_domain",
 		.mode		= 0555,
 	},
-	{0,},
+	{0, },
 };
 
 static struct ctl_table sd_ctl_root[] = {
@@ -5375,7 +5375,7 @@ static struct ctl_table sd_ctl_root[] = {
 		.mode		= 0555,
 		.child		= sd_ctl_dir,
 	},
-	{0,},
+	{0, },
 };
 
 static struct ctl_table *sd_alloc_ctl_entry(int n)
@@ -7019,8 +7019,8 @@ err:
 /* rcu callback to free various structures associated with a task group */
 static void free_sched_group(struct rcu_head *rhp)
 {
-	struct cfs_rq *cfs_rq = container_of(rhp, struct cfs_rq, rcu);
-	struct task_group *tg = cfs_rq->tg;
+	struct task_group *tg = container_of(rhp, struct task_group, rcu);
+	struct cfs_rq *cfs_rq;
 	struct sched_entity *se;
 	int i;
 
@@ -7041,7 +7041,7 @@ static void free_sched_group(struct rcu_head *rhp)
 /* Destroy runqueue etc associated with a task group */
 void sched_destroy_group(struct task_group *tg)
 {
-	struct cfs_rq *cfs_rq;
+	struct cfs_rq *cfs_rq = NULL;
 	int i;
 
 	for_each_possible_cpu(i) {
@@ -7049,10 +7049,10 @@ void sched_destroy_group(struct task_group *tg)
 		list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
 	}
 
-	cfs_rq = tg->cfs_rq[0];
+	BUG_ON(!cfs_rq);
 
 	/* wait for possible concurrent references to cfs_rqs complete */
-	call_rcu(&cfs_rq->rcu, free_sched_group);
+	call_rcu(&tg->rcu, free_sched_group);
 }
 
 /* change task's runqueue when it moves between groups.
@@ -7211,25 +7211,53 @@ static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft)
 	return (u64) tg->shares;
 }
 
-static struct cftype cpu_shares = {
-	.name = "shares",
-	.read_uint = cpu_shares_read_uint,
-	.write_uint = cpu_shares_write_uint,
+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, 1000000);
+
+	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)
 {
-	return cgroup_add_file(cont, ss, &cpu_shares);
+	return cgroup_add_files(cont, ss, cpu_files, ARRAY_SIZE(cpu_files));
 }
 
 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,
+	.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,
 };
 

kernel/sched_fair.c

@@ -1025,7 +1025,7 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr)
 	}
 }
 
-#define swap(a,b) do { typeof(a) tmp = (a); (a) = (b); (b) = tmp; } while (0)
+#define swap(a, b) do { typeof(a) tmp = (a); (a) = (b); (b) = tmp; } while (0)
 
 /*
  * Share the fairness runtime between parent and child, thus the