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1// SPDX-License-Identifier: GPL-2.0
2
3/*
4 * CPU accounting code for task groups.
5 *
6 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
7 * (balbir@in.ibm.com).
8 */
9
10/* Time spent by the tasks of the CPU accounting group executing in ... */
11enum cpuacct_stat_index {
12 CPUACCT_STAT_USER, /* ... user mode */
13 CPUACCT_STAT_SYSTEM, /* ... kernel mode */
14
15 CPUACCT_STAT_NSTATS,
16};
17
18static const char * const cpuacct_stat_desc[] = {
19 [CPUACCT_STAT_USER] = "user",
20 [CPUACCT_STAT_SYSTEM] = "system",
21};
22
23/* track CPU usage of a group of tasks and its child groups */
24struct cpuacct {
25 struct cgroup_subsys_state css;
26 /* cpuusage holds pointer to a u64-type object on every CPU */
27 u64 __percpu *cpuusage;
28 struct kernel_cpustat __percpu *cpustat;
29};
30
31static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css)
32{
33 return css ? container_of(css, struct cpuacct, css) : NULL;
34}
35
36/* Return CPU accounting group to which this task belongs */
37static inline struct cpuacct *task_ca(struct task_struct *tsk)
38{
39 return css_ca(task_css(tsk, cpuacct_cgrp_id));
40}
41
42static inline struct cpuacct *parent_ca(struct cpuacct *ca)
43{
44 return css_ca(ca->css.parent);
45}
46
47static DEFINE_PER_CPU(u64, root_cpuacct_cpuusage);
48static struct cpuacct root_cpuacct = {
49 .cpustat = &kernel_cpustat,
50 .cpuusage = &root_cpuacct_cpuusage,
51};
52
53/* Create a new CPU accounting group */
54static struct cgroup_subsys_state *
55cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
56{
57 struct cpuacct *ca;
58
59 if (!parent_css)
60 return &root_cpuacct.css;
61
62 ca = kzalloc(sizeof(*ca), GFP_KERNEL);
63 if (!ca)
64 goto out;
65
66 ca->cpuusage = alloc_percpu(u64);
67 if (!ca->cpuusage)
68 goto out_free_ca;
69
70 ca->cpustat = alloc_percpu(struct kernel_cpustat);
71 if (!ca->cpustat)
72 goto out_free_cpuusage;
73
74 return &ca->css;
75
76out_free_cpuusage:
77 free_percpu(ca->cpuusage);
78out_free_ca:
79 kfree(ca);
80out:
81 return ERR_PTR(-ENOMEM);
82}
83
84/* Destroy an existing CPU accounting group */
85static void cpuacct_css_free(struct cgroup_subsys_state *css)
86{
87 struct cpuacct *ca = css_ca(css);
88
89 free_percpu(ca->cpustat);
90 free_percpu(ca->cpuusage);
91 kfree(ca);
92}
93
94static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu,
95 enum cpuacct_stat_index index)
96{
97 u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
98 u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;
99 u64 data;
100
101 /*
102 * We allow index == CPUACCT_STAT_NSTATS here to read
103 * the sum of usages.
104 */
105 if (WARN_ON_ONCE(index > CPUACCT_STAT_NSTATS))
106 return 0;
107
108#ifndef CONFIG_64BIT
109 /*
110 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
111 */
112 raw_spin_rq_lock_irq(cpu_rq(cpu));
113#endif
114
115 switch (index) {
116 case CPUACCT_STAT_USER:
117 data = cpustat[CPUTIME_USER] + cpustat[CPUTIME_NICE];
118 break;
119 case CPUACCT_STAT_SYSTEM:
120 data = cpustat[CPUTIME_SYSTEM] + cpustat[CPUTIME_IRQ] +
121 cpustat[CPUTIME_SOFTIRQ];
122 break;
123 case CPUACCT_STAT_NSTATS:
124 data = *cpuusage;
125 break;
126 }
127
128#ifndef CONFIG_64BIT
129 raw_spin_rq_unlock_irq(cpu_rq(cpu));
130#endif
131
132 return data;
133}
134
135static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu)
136{
137 u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
138 u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;
139
140 /* Don't allow to reset global kernel_cpustat */
141 if (ca == &root_cpuacct)
142 return;
143
144#ifndef CONFIG_64BIT
145 /*
146 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
147 */
148 raw_spin_rq_lock_irq(cpu_rq(cpu));
149#endif
150 *cpuusage = 0;
151 cpustat[CPUTIME_USER] = cpustat[CPUTIME_NICE] = 0;
152 cpustat[CPUTIME_SYSTEM] = cpustat[CPUTIME_IRQ] = 0;
153 cpustat[CPUTIME_SOFTIRQ] = 0;
154
155#ifndef CONFIG_64BIT
156 raw_spin_rq_unlock_irq(cpu_rq(cpu));
157#endif
158}
159
160/* Return total CPU usage (in nanoseconds) of a group */
161static u64 __cpuusage_read(struct cgroup_subsys_state *css,
162 enum cpuacct_stat_index index)
163{
164 struct cpuacct *ca = css_ca(css);
165 u64 totalcpuusage = 0;
166 int i;
167
168 for_each_possible_cpu(i)
169 totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
170
171 return totalcpuusage;
172}
173
174static u64 cpuusage_user_read(struct cgroup_subsys_state *css,
175 struct cftype *cft)
176{
177 return __cpuusage_read(css, CPUACCT_STAT_USER);
178}
179
180static u64 cpuusage_sys_read(struct cgroup_subsys_state *css,
181 struct cftype *cft)
182{
183 return __cpuusage_read(css, CPUACCT_STAT_SYSTEM);
184}
185
186static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
187{
188 return __cpuusage_read(css, CPUACCT_STAT_NSTATS);
189}
190
191static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
192 u64 val)
193{
194 struct cpuacct *ca = css_ca(css);
195 int cpu;
196
197 /*
198 * Only allow '0' here to do a reset.
199 */
200 if (val)
201 return -EINVAL;
202
203 for_each_possible_cpu(cpu)
204 cpuacct_cpuusage_write(ca, cpu);
205
206 return 0;
207}
208
209static int __cpuacct_percpu_seq_show(struct seq_file *m,
210 enum cpuacct_stat_index index)
211{
212 struct cpuacct *ca = css_ca(seq_css(m));
213 u64 percpu;
214 int i;
215
216 for_each_possible_cpu(i) {
217 percpu = cpuacct_cpuusage_read(ca, i, index);
218 seq_printf(m, "%llu ", (unsigned long long) percpu);
219 }
220 seq_printf(m, "\n");
221 return 0;
222}
223
224static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V)
225{
226 return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_USER);
227}
228
229static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V)
230{
231 return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_SYSTEM);
232}
233
234static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
235{
236 return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_NSTATS);
237}
238
239static int cpuacct_all_seq_show(struct seq_file *m, void *V)
240{
241 struct cpuacct *ca = css_ca(seq_css(m));
242 int index;
243 int cpu;
244
245 seq_puts(m, "cpu");
246 for (index = 0; index < CPUACCT_STAT_NSTATS; index++)
247 seq_printf(m, " %s", cpuacct_stat_desc[index]);
248 seq_puts(m, "\n");
249
250 for_each_possible_cpu(cpu) {
251 seq_printf(m, "%d", cpu);
252 for (index = 0; index < CPUACCT_STAT_NSTATS; index++)
253 seq_printf(m, " %llu",
254 cpuacct_cpuusage_read(ca, cpu, index));
255 seq_puts(m, "\n");
256 }
257 return 0;
258}
259
260static int cpuacct_stats_show(struct seq_file *sf, void *v)
261{
262 struct cpuacct *ca = css_ca(seq_css(sf));
263 struct task_cputime cputime;
264 u64 val[CPUACCT_STAT_NSTATS];
265 int cpu;
266 int stat;
267
268 memset(&cputime, 0, sizeof(cputime));
269 for_each_possible_cpu(cpu) {
270 u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;
271
272 cputime.utime += cpustat[CPUTIME_USER];
273 cputime.utime += cpustat[CPUTIME_NICE];
274 cputime.stime += cpustat[CPUTIME_SYSTEM];
275 cputime.stime += cpustat[CPUTIME_IRQ];
276 cputime.stime += cpustat[CPUTIME_SOFTIRQ];
277
278 cputime.sum_exec_runtime += *per_cpu_ptr(ca->cpuusage, cpu);
279 }
280
281 cputime_adjust(&cputime, &seq_css(sf)->cgroup->prev_cputime,
282 &val[CPUACCT_STAT_USER], &val[CPUACCT_STAT_SYSTEM]);
283
284 for (stat = 0; stat < CPUACCT_STAT_NSTATS; stat++) {
285 seq_printf(sf, "%s %llu\n", cpuacct_stat_desc[stat],
286 nsec_to_clock_t(val[stat]));
287 }
288
289 return 0;
290}
291
292static struct cftype files[] = {
293 {
294 .name = "usage",
295 .read_u64 = cpuusage_read,
296 .write_u64 = cpuusage_write,
297 },
298 {
299 .name = "usage_user",
300 .read_u64 = cpuusage_user_read,
301 },
302 {
303 .name = "usage_sys",
304 .read_u64 = cpuusage_sys_read,
305 },
306 {
307 .name = "usage_percpu",
308 .seq_show = cpuacct_percpu_seq_show,
309 },
310 {
311 .name = "usage_percpu_user",
312 .seq_show = cpuacct_percpu_user_seq_show,
313 },
314 {
315 .name = "usage_percpu_sys",
316 .seq_show = cpuacct_percpu_sys_seq_show,
317 },
318 {
319 .name = "usage_all",
320 .seq_show = cpuacct_all_seq_show,
321 },
322 {
323 .name = "stat",
324 .seq_show = cpuacct_stats_show,
325 },
326 { } /* terminate */
327};
328
329/*
330 * charge this task's execution time to its accounting group.
331 *
332 * called with rq->lock held.
333 */
334void cpuacct_charge(struct task_struct *tsk, u64 cputime)
335{
336 unsigned int cpu = task_cpu(tsk);
337 struct cpuacct *ca;
338
339 lockdep_assert_rq_held(cpu_rq(cpu));
340
341 for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
342 *per_cpu_ptr(ca->cpuusage, cpu) += cputime;
343}
344
345/*
346 * Add user/system time to cpuacct.
347 *
348 * Note: it's the caller that updates the account of the root cgroup.
349 */
350void cpuacct_account_field(struct task_struct *tsk, int index, u64 val)
351{
352 struct cpuacct *ca;
353
354 for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca))
355 __this_cpu_add(ca->cpustat->cpustat[index], val);
356}
357
358struct cgroup_subsys cpuacct_cgrp_subsys = {
359 .css_alloc = cpuacct_css_alloc,
360 .css_free = cpuacct_css_free,
361 .legacy_cftypes = files,
362 .early_init = true,
363};
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * CPU accounting code for task groups.
4 *
5 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
6 * (balbir@in.ibm.com).
7 */
8#include <asm/irq_regs.h>
9#include "sched.h"
10
11/* Time spent by the tasks of the CPU accounting group executing in ... */
12enum cpuacct_stat_index {
13 CPUACCT_STAT_USER, /* ... user mode */
14 CPUACCT_STAT_SYSTEM, /* ... kernel mode */
15
16 CPUACCT_STAT_NSTATS,
17};
18
19static const char * const cpuacct_stat_desc[] = {
20 [CPUACCT_STAT_USER] = "user",
21 [CPUACCT_STAT_SYSTEM] = "system",
22};
23
24struct cpuacct_usage {
25 u64 usages[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 struct cpuacct_usage __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(struct cpuacct_usage, 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(struct cpuacct_usage);
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 enum cpuacct_stat_index index)
101{
102 struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
103 u64 data;
104
105 /*
106 * We allow index == CPUACCT_STAT_NSTATS here to read
107 * the sum of suages.
108 */
109 BUG_ON(index > CPUACCT_STAT_NSTATS);
110
111#ifndef CONFIG_64BIT
112 /*
113 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
114 */
115 raw_spin_lock_irq(&cpu_rq(cpu)->lock);
116#endif
117
118 if (index == CPUACCT_STAT_NSTATS) {
119 int i = 0;
120
121 data = 0;
122 for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
123 data += cpuusage->usages[i];
124 } else {
125 data = cpuusage->usages[index];
126 }
127
128#ifndef CONFIG_64BIT
129 raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
130#endif
131
132 return data;
133}
134
135static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
136{
137 struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
138 int i;
139
140#ifndef CONFIG_64BIT
141 /*
142 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
143 */
144 raw_spin_lock_irq(&cpu_rq(cpu)->lock);
145#endif
146
147 for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
148 cpuusage->usages[i] = val;
149
150#ifndef CONFIG_64BIT
151 raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
152#endif
153}
154
155/* Return total CPU usage (in nanoseconds) of a group */
156static u64 __cpuusage_read(struct cgroup_subsys_state *css,
157 enum cpuacct_stat_index index)
158{
159 struct cpuacct *ca = css_ca(css);
160 u64 totalcpuusage = 0;
161 int i;
162
163 for_each_possible_cpu(i)
164 totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
165
166 return totalcpuusage;
167}
168
169static u64 cpuusage_user_read(struct cgroup_subsys_state *css,
170 struct cftype *cft)
171{
172 return __cpuusage_read(css, CPUACCT_STAT_USER);
173}
174
175static u64 cpuusage_sys_read(struct cgroup_subsys_state *css,
176 struct cftype *cft)
177{
178 return __cpuusage_read(css, CPUACCT_STAT_SYSTEM);
179}
180
181static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
182{
183 return __cpuusage_read(css, CPUACCT_STAT_NSTATS);
184}
185
186static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
187 u64 val)
188{
189 struct cpuacct *ca = css_ca(css);
190 int cpu;
191
192 /*
193 * Only allow '0' here to do a reset.
194 */
195 if (val)
196 return -EINVAL;
197
198 for_each_possible_cpu(cpu)
199 cpuacct_cpuusage_write(ca, cpu, 0);
200
201 return 0;
202}
203
204static int __cpuacct_percpu_seq_show(struct seq_file *m,
205 enum cpuacct_stat_index index)
206{
207 struct cpuacct *ca = css_ca(seq_css(m));
208 u64 percpu;
209 int i;
210
211 for_each_possible_cpu(i) {
212 percpu = cpuacct_cpuusage_read(ca, i, index);
213 seq_printf(m, "%llu ", (unsigned long long) percpu);
214 }
215 seq_printf(m, "\n");
216 return 0;
217}
218
219static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V)
220{
221 return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_USER);
222}
223
224static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V)
225{
226 return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_SYSTEM);
227}
228
229static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
230{
231 return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_NSTATS);
232}
233
234static int cpuacct_all_seq_show(struct seq_file *m, void *V)
235{
236 struct cpuacct *ca = css_ca(seq_css(m));
237 int index;
238 int cpu;
239
240 seq_puts(m, "cpu");
241 for (index = 0; index < CPUACCT_STAT_NSTATS; index++)
242 seq_printf(m, " %s", cpuacct_stat_desc[index]);
243 seq_puts(m, "\n");
244
245 for_each_possible_cpu(cpu) {
246 struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
247
248 seq_printf(m, "%d", cpu);
249
250 for (index = 0; index < CPUACCT_STAT_NSTATS; index++) {
251#ifndef CONFIG_64BIT
252 /*
253 * Take rq->lock to make 64-bit read safe on 32-bit
254 * platforms.
255 */
256 raw_spin_lock_irq(&cpu_rq(cpu)->lock);
257#endif
258
259 seq_printf(m, " %llu", cpuusage->usages[index]);
260
261#ifndef CONFIG_64BIT
262 raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
263#endif
264 }
265 seq_puts(m, "\n");
266 }
267 return 0;
268}
269
270static int cpuacct_stats_show(struct seq_file *sf, void *v)
271{
272 struct cpuacct *ca = css_ca(seq_css(sf));
273 s64 val[CPUACCT_STAT_NSTATS];
274 int cpu;
275 int stat;
276
277 memset(val, 0, sizeof(val));
278 for_each_possible_cpu(cpu) {
279 u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;
280
281 val[CPUACCT_STAT_USER] += cpustat[CPUTIME_USER];
282 val[CPUACCT_STAT_USER] += cpustat[CPUTIME_NICE];
283 val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SYSTEM];
284 val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_IRQ];
285 val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SOFTIRQ];
286 }
287
288 for (stat = 0; stat < CPUACCT_STAT_NSTATS; stat++) {
289 seq_printf(sf, "%s %lld\n",
290 cpuacct_stat_desc[stat],
291 (long long)nsec_to_clock_t(val[stat]));
292 }
293
294 return 0;
295}
296
297static struct cftype files[] = {
298 {
299 .name = "usage",
300 .read_u64 = cpuusage_read,
301 .write_u64 = cpuusage_write,
302 },
303 {
304 .name = "usage_user",
305 .read_u64 = cpuusage_user_read,
306 },
307 {
308 .name = "usage_sys",
309 .read_u64 = cpuusage_sys_read,
310 },
311 {
312 .name = "usage_percpu",
313 .seq_show = cpuacct_percpu_seq_show,
314 },
315 {
316 .name = "usage_percpu_user",
317 .seq_show = cpuacct_percpu_user_seq_show,
318 },
319 {
320 .name = "usage_percpu_sys",
321 .seq_show = cpuacct_percpu_sys_seq_show,
322 },
323 {
324 .name = "usage_all",
325 .seq_show = cpuacct_all_seq_show,
326 },
327 {
328 .name = "stat",
329 .seq_show = cpuacct_stats_show,
330 },
331 { } /* terminate */
332};
333
334/*
335 * charge this task's execution time to its accounting group.
336 *
337 * called with rq->lock held.
338 */
339void cpuacct_charge(struct task_struct *tsk, u64 cputime)
340{
341 struct cpuacct *ca;
342 int index = CPUACCT_STAT_SYSTEM;
343 struct pt_regs *regs = get_irq_regs() ? : task_pt_regs(tsk);
344
345 if (regs && user_mode(regs))
346 index = CPUACCT_STAT_USER;
347
348 rcu_read_lock();
349
350 for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
351 __this_cpu_add(ca->cpuusage->usages[index], cputime);
352
353 rcu_read_unlock();
354}
355
356/*
357 * Add user/system time to cpuacct.
358 *
359 * Note: it's the caller that updates the account of the root cgroup.
360 */
361void cpuacct_account_field(struct task_struct *tsk, int index, u64 val)
362{
363 struct cpuacct *ca;
364
365 rcu_read_lock();
366 for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca))
367 __this_cpu_add(ca->cpustat->cpustat[index], val);
368 rcu_read_unlock();
369}
370
371struct cgroup_subsys cpuacct_cgrp_subsys = {
372 .css_alloc = cpuacct_css_alloc,
373 .css_free = cpuacct_css_free,
374 .legacy_cftypes = files,
375 .early_init = true,
376};