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v3.15
  1#include <linux/cgroup.h>
  2#include <linux/slab.h>
  3#include <linux/percpu.h>
  4#include <linux/spinlock.h>
  5#include <linux/cpumask.h>
  6#include <linux/seq_file.h>
  7#include <linux/rcupdate.h>
  8#include <linux/kernel_stat.h>
  9#include <linux/err.h>
 10
 11#include "sched.h"
 12
 13/*
 14 * CPU accounting code for task groups.
 15 *
 16 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
 17 * (balbir@in.ibm.com).
 18 */
 19
 20/* Time spent by the tasks of the cpu accounting group executing in ... */
 21enum cpuacct_stat_index {
 22	CPUACCT_STAT_USER,	/* ... user mode */
 23	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */
 24
 25	CPUACCT_STAT_NSTATS,
 26};
 27
 28/* track cpu usage of a group of tasks and its child groups */
 29struct cpuacct {
 30	struct cgroup_subsys_state css;
 31	/* cpuusage holds pointer to a u64-type object on every cpu */
 32	u64 __percpu *cpuusage;
 33	struct kernel_cpustat __percpu *cpustat;
 34};
 35
 36static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css)
 37{
 38	return css ? container_of(css, struct cpuacct, css) : NULL;
 39}
 40
 41/* return cpu accounting group to which this task belongs */
 42static inline struct cpuacct *task_ca(struct task_struct *tsk)
 43{
 44	return css_ca(task_css(tsk, cpuacct_cgrp_id));
 45}
 46
 47static inline struct cpuacct *parent_ca(struct cpuacct *ca)
 48{
 49	return css_ca(css_parent(&ca->css));
 50}
 51
 52static DEFINE_PER_CPU(u64, root_cpuacct_cpuusage);
 53static struct cpuacct root_cpuacct = {
 54	.cpustat	= &kernel_cpustat,
 55	.cpuusage	= &root_cpuacct_cpuusage,
 56};
 57
 58/* create a new cpu accounting group */
 59static struct cgroup_subsys_state *
 60cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
 61{
 62	struct cpuacct *ca;
 63
 64	if (!parent_css)
 65		return &root_cpuacct.css;
 66
 67	ca = kzalloc(sizeof(*ca), GFP_KERNEL);
 68	if (!ca)
 69		goto out;
 70
 71	ca->cpuusage = alloc_percpu(u64);
 72	if (!ca->cpuusage)
 73		goto out_free_ca;
 74
 75	ca->cpustat = alloc_percpu(struct kernel_cpustat);
 76	if (!ca->cpustat)
 77		goto out_free_cpuusage;
 78
 79	return &ca->css;
 80
 81out_free_cpuusage:
 82	free_percpu(ca->cpuusage);
 83out_free_ca:
 84	kfree(ca);
 85out:
 86	return ERR_PTR(-ENOMEM);
 87}
 88
 89/* destroy an existing cpu accounting group */
 90static void cpuacct_css_free(struct cgroup_subsys_state *css)
 91{
 92	struct cpuacct *ca = css_ca(css);
 93
 94	free_percpu(ca->cpustat);
 95	free_percpu(ca->cpuusage);
 96	kfree(ca);
 97}
 98
 99static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
100{
101	u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
102	u64 data;
103
104#ifndef CONFIG_64BIT
105	/*
106	 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
107	 */
108	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
109	data = *cpuusage;
110	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
111#else
112	data = *cpuusage;
113#endif
114
115	return data;
116}
117
118static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
119{
120	u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
121
122#ifndef CONFIG_64BIT
123	/*
124	 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
125	 */
126	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
127	*cpuusage = val;
128	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
129#else
130	*cpuusage = val;
131#endif
132}
133
134/* return total cpu usage (in nanoseconds) of a group */
135static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
136{
137	struct cpuacct *ca = css_ca(css);
138	u64 totalcpuusage = 0;
139	int i;
140
141	for_each_present_cpu(i)
142		totalcpuusage += cpuacct_cpuusage_read(ca, i);
143
144	return totalcpuusage;
145}
146
147static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
148			  u64 reset)
149{
150	struct cpuacct *ca = css_ca(css);
151	int err = 0;
152	int i;
153
154	if (reset) {
 
 
 
155		err = -EINVAL;
156		goto out;
157	}
158
159	for_each_present_cpu(i)
160		cpuacct_cpuusage_write(ca, i, 0);
161
162out:
163	return err;
164}
165
166static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
167{
168	struct cpuacct *ca = css_ca(seq_css(m));
169	u64 percpu;
170	int i;
171
172	for_each_present_cpu(i) {
173		percpu = cpuacct_cpuusage_read(ca, i);
174		seq_printf(m, "%llu ", (unsigned long long) percpu);
175	}
176	seq_printf(m, "\n");
177	return 0;
178}
179
180static const char * const cpuacct_stat_desc[] = {
181	[CPUACCT_STAT_USER] = "user",
182	[CPUACCT_STAT_SYSTEM] = "system",
183};
184
185static int cpuacct_stats_show(struct seq_file *sf, void *v)
186{
187	struct cpuacct *ca = css_ca(seq_css(sf));
188	int cpu;
189	s64 val = 0;
190
191	for_each_online_cpu(cpu) {
192		struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
193		val += kcpustat->cpustat[CPUTIME_USER];
194		val += kcpustat->cpustat[CPUTIME_NICE];
195	}
196	val = cputime64_to_clock_t(val);
197	seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val);
198
199	val = 0;
200	for_each_online_cpu(cpu) {
201		struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
202		val += kcpustat->cpustat[CPUTIME_SYSTEM];
203		val += kcpustat->cpustat[CPUTIME_IRQ];
204		val += kcpustat->cpustat[CPUTIME_SOFTIRQ];
205	}
206
207	val = cputime64_to_clock_t(val);
208	seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val);
209
210	return 0;
211}
212
213static struct cftype files[] = {
214	{
215		.name = "usage",
216		.read_u64 = cpuusage_read,
217		.write_u64 = cpuusage_write,
218	},
219	{
220		.name = "usage_percpu",
221		.seq_show = cpuacct_percpu_seq_show,
222	},
223	{
224		.name = "stat",
225		.seq_show = cpuacct_stats_show,
226	},
227	{ }	/* terminate */
228};
229
230/*
231 * charge this task's execution time to its accounting group.
232 *
233 * called with rq->lock held.
234 */
235void cpuacct_charge(struct task_struct *tsk, u64 cputime)
236{
237	struct cpuacct *ca;
238	int cpu;
239
240	cpu = task_cpu(tsk);
241
242	rcu_read_lock();
243
244	ca = task_ca(tsk);
245
246	while (true) {
247		u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
248		*cpuusage += cputime;
249
250		ca = parent_ca(ca);
251		if (!ca)
252			break;
253	}
254
255	rcu_read_unlock();
256}
257
258/*
259 * Add user/system time to cpuacct.
260 *
261 * Note: it's the caller that updates the account of the root cgroup.
262 */
263void cpuacct_account_field(struct task_struct *p, int index, u64 val)
264{
265	struct kernel_cpustat *kcpustat;
266	struct cpuacct *ca;
267
268	rcu_read_lock();
269	ca = task_ca(p);
270	while (ca != &root_cpuacct) {
271		kcpustat = this_cpu_ptr(ca->cpustat);
272		kcpustat->cpustat[index] += val;
273		ca = parent_ca(ca);
274	}
275	rcu_read_unlock();
276}
277
278struct cgroup_subsys cpuacct_cgrp_subsys = {
279	.css_alloc	= cpuacct_css_alloc,
280	.css_free	= cpuacct_css_free,
281	.base_cftypes	= files,
282	.early_init	= 1,
283};
v4.6
  1#include <linux/cgroup.h>
  2#include <linux/slab.h>
  3#include <linux/percpu.h>
  4#include <linux/spinlock.h>
  5#include <linux/cpumask.h>
  6#include <linux/seq_file.h>
  7#include <linux/rcupdate.h>
  8#include <linux/kernel_stat.h>
  9#include <linux/err.h>
 10
 11#include "sched.h"
 12
 13/*
 14 * CPU accounting code for task groups.
 15 *
 16 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
 17 * (balbir@in.ibm.com).
 18 */
 19
 20/* Time spent by the tasks of the cpu accounting group executing in ... */
 21enum cpuacct_stat_index {
 22	CPUACCT_STAT_USER,	/* ... user mode */
 23	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */
 24
 25	CPUACCT_STAT_NSTATS,
 26};
 27
 28/* track cpu usage of a group of tasks and its child groups */
 29struct cpuacct {
 30	struct cgroup_subsys_state css;
 31	/* cpuusage holds pointer to a u64-type object on every cpu */
 32	u64 __percpu *cpuusage;
 33	struct kernel_cpustat __percpu *cpustat;
 34};
 35
 36static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css)
 37{
 38	return css ? container_of(css, struct cpuacct, css) : NULL;
 39}
 40
 41/* return cpu accounting group to which this task belongs */
 42static inline struct cpuacct *task_ca(struct task_struct *tsk)
 43{
 44	return css_ca(task_css(tsk, cpuacct_cgrp_id));
 45}
 46
 47static inline struct cpuacct *parent_ca(struct cpuacct *ca)
 48{
 49	return css_ca(ca->css.parent);
 50}
 51
 52static DEFINE_PER_CPU(u64, root_cpuacct_cpuusage);
 53static struct cpuacct root_cpuacct = {
 54	.cpustat	= &kernel_cpustat,
 55	.cpuusage	= &root_cpuacct_cpuusage,
 56};
 57
 58/* create a new cpu accounting group */
 59static struct cgroup_subsys_state *
 60cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
 61{
 62	struct cpuacct *ca;
 63
 64	if (!parent_css)
 65		return &root_cpuacct.css;
 66
 67	ca = kzalloc(sizeof(*ca), GFP_KERNEL);
 68	if (!ca)
 69		goto out;
 70
 71	ca->cpuusage = alloc_percpu(u64);
 72	if (!ca->cpuusage)
 73		goto out_free_ca;
 74
 75	ca->cpustat = alloc_percpu(struct kernel_cpustat);
 76	if (!ca->cpustat)
 77		goto out_free_cpuusage;
 78
 79	return &ca->css;
 80
 81out_free_cpuusage:
 82	free_percpu(ca->cpuusage);
 83out_free_ca:
 84	kfree(ca);
 85out:
 86	return ERR_PTR(-ENOMEM);
 87}
 88
 89/* destroy an existing cpu accounting group */
 90static void cpuacct_css_free(struct cgroup_subsys_state *css)
 91{
 92	struct cpuacct *ca = css_ca(css);
 93
 94	free_percpu(ca->cpustat);
 95	free_percpu(ca->cpuusage);
 96	kfree(ca);
 97}
 98
 99static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
100{
101	u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
102	u64 data;
103
104#ifndef CONFIG_64BIT
105	/*
106	 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
107	 */
108	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
109	data = *cpuusage;
110	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
111#else
112	data = *cpuusage;
113#endif
114
115	return data;
116}
117
118static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
119{
120	u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
121
122#ifndef CONFIG_64BIT
123	/*
124	 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
125	 */
126	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
127	*cpuusage = val;
128	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
129#else
130	*cpuusage = val;
131#endif
132}
133
134/* return total cpu usage (in nanoseconds) of a group */
135static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
136{
137	struct cpuacct *ca = css_ca(css);
138	u64 totalcpuusage = 0;
139	int i;
140
141	for_each_present_cpu(i)
142		totalcpuusage += cpuacct_cpuusage_read(ca, i);
143
144	return totalcpuusage;
145}
146
147static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
148			  u64 val)
149{
150	struct cpuacct *ca = css_ca(css);
151	int err = 0;
152	int i;
153
154	/*
155	 * Only allow '0' here to do a reset.
156	 */
157	if (val) {
158		err = -EINVAL;
159		goto out;
160	}
161
162	for_each_present_cpu(i)
163		cpuacct_cpuusage_write(ca, i, 0);
164
165out:
166	return err;
167}
168
169static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
170{
171	struct cpuacct *ca = css_ca(seq_css(m));
172	u64 percpu;
173	int i;
174
175	for_each_present_cpu(i) {
176		percpu = cpuacct_cpuusage_read(ca, i);
177		seq_printf(m, "%llu ", (unsigned long long) percpu);
178	}
179	seq_printf(m, "\n");
180	return 0;
181}
182
183static const char * const cpuacct_stat_desc[] = {
184	[CPUACCT_STAT_USER] = "user",
185	[CPUACCT_STAT_SYSTEM] = "system",
186};
187
188static int cpuacct_stats_show(struct seq_file *sf, void *v)
189{
190	struct cpuacct *ca = css_ca(seq_css(sf));
191	int cpu;
192	s64 val = 0;
193
194	for_each_online_cpu(cpu) {
195		struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
196		val += kcpustat->cpustat[CPUTIME_USER];
197		val += kcpustat->cpustat[CPUTIME_NICE];
198	}
199	val = cputime64_to_clock_t(val);
200	seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val);
201
202	val = 0;
203	for_each_online_cpu(cpu) {
204		struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
205		val += kcpustat->cpustat[CPUTIME_SYSTEM];
206		val += kcpustat->cpustat[CPUTIME_IRQ];
207		val += kcpustat->cpustat[CPUTIME_SOFTIRQ];
208	}
209
210	val = cputime64_to_clock_t(val);
211	seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val);
212
213	return 0;
214}
215
216static struct cftype files[] = {
217	{
218		.name = "usage",
219		.read_u64 = cpuusage_read,
220		.write_u64 = cpuusage_write,
221	},
222	{
223		.name = "usage_percpu",
224		.seq_show = cpuacct_percpu_seq_show,
225	},
226	{
227		.name = "stat",
228		.seq_show = cpuacct_stats_show,
229	},
230	{ }	/* terminate */
231};
232
233/*
234 * charge this task's execution time to its accounting group.
235 *
236 * called with rq->lock held.
237 */
238void cpuacct_charge(struct task_struct *tsk, u64 cputime)
239{
240	struct cpuacct *ca;
 
 
 
241
242	rcu_read_lock();
243	for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
244		*this_cpu_ptr(ca->cpuusage) += cputime;
 
 
 
 
 
 
 
 
 
 
245	rcu_read_unlock();
246}
247
248/*
249 * Add user/system time to cpuacct.
250 *
251 * Note: it's the caller that updates the account of the root cgroup.
252 */
253void cpuacct_account_field(struct task_struct *tsk, int index, u64 val)
254{
 
255	struct cpuacct *ca;
256
257	rcu_read_lock();
258	for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca))
259		this_cpu_ptr(ca->cpustat)->cpustat[index] += val;
 
 
 
 
260	rcu_read_unlock();
261}
262
263struct cgroup_subsys cpuacct_cgrp_subsys = {
264	.css_alloc	= cpuacct_css_alloc,
265	.css_free	= cpuacct_css_free,
266	.legacy_cftypes	= files,
267	.early_init	= true,
268};