Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6.git] / kernel / sched_stats.h
1
2 #ifdef CONFIG_SCHEDSTATS
3 /*
4  * bump this up when changing the output format or the meaning of an existing
5  * format, so that tools can adapt (or abort)
6  */
7 #define SCHEDSTAT_VERSION 15
8
9 static int show_schedstat(struct seq_file *seq, void *v)
10 {
11         int cpu;
12         int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9;
13         char *mask_str = kmalloc(mask_len, GFP_KERNEL);
14
15         if (mask_str == NULL)
16                 return -ENOMEM;
17
18         seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION);
19         seq_printf(seq, "timestamp %lu\n", jiffies);
20         for_each_online_cpu(cpu) {
21                 struct rq *rq = cpu_rq(cpu);
22 #ifdef CONFIG_SMP
23                 struct sched_domain *sd;
24                 int dcount = 0;
25 #endif
26
27                 /* runqueue-specific stats */
28                 seq_printf(seq,
29                     "cpu%d %u %u %u %u %u %u %llu %llu %lu",
30                     cpu, rq->yld_count,
31                     rq->sched_switch, rq->sched_count, rq->sched_goidle,
32                     rq->ttwu_count, rq->ttwu_local,
33                     rq->rq_cpu_time,
34                     rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
35
36                 seq_printf(seq, "\n");
37
38 #ifdef CONFIG_SMP
39                 /* domain-specific stats */
40                 preempt_disable();
41                 for_each_domain(cpu, sd) {
42                         enum cpu_idle_type itype;
43
44                         cpumask_scnprintf(mask_str, mask_len,
45                                           sched_domain_span(sd));
46                         seq_printf(seq, "domain%d %s", dcount++, mask_str);
47                         for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
48                                         itype++) {
49                                 seq_printf(seq, " %u %u %u %u %u %u %u %u",
50                                     sd->lb_count[itype],
51                                     sd->lb_balanced[itype],
52                                     sd->lb_failed[itype],
53                                     sd->lb_imbalance[itype],
54                                     sd->lb_gained[itype],
55                                     sd->lb_hot_gained[itype],
56                                     sd->lb_nobusyq[itype],
57                                     sd->lb_nobusyg[itype]);
58                         }
59                         seq_printf(seq,
60                                    " %u %u %u %u %u %u %u %u %u %u %u %u\n",
61                             sd->alb_count, sd->alb_failed, sd->alb_pushed,
62                             sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed,
63                             sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed,
64                             sd->ttwu_wake_remote, sd->ttwu_move_affine,
65                             sd->ttwu_move_balance);
66                 }
67                 preempt_enable();
68 #endif
69         }
70         kfree(mask_str);
71         return 0;
72 }
73
74 static int schedstat_open(struct inode *inode, struct file *file)
75 {
76         unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32);
77         char *buf = kmalloc(size, GFP_KERNEL);
78         struct seq_file *m;
79         int res;
80
81         if (!buf)
82                 return -ENOMEM;
83         res = single_open(file, show_schedstat, NULL);
84         if (!res) {
85                 m = file->private_data;
86                 m->buf = buf;
87                 m->size = size;
88         } else
89                 kfree(buf);
90         return res;
91 }
92
93 static const struct file_operations proc_schedstat_operations = {
94         .open    = schedstat_open,
95         .read    = seq_read,
96         .llseek  = seq_lseek,
97         .release = single_release,
98 };
99
100 static int __init proc_schedstat_init(void)
101 {
102         proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
103         return 0;
104 }
105 module_init(proc_schedstat_init);
106
107 /*
108  * Expects runqueue lock to be held for atomicity of update
109  */
110 static inline void
111 rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
112 {
113         if (rq) {
114                 rq->rq_sched_info.run_delay += delta;
115                 rq->rq_sched_info.pcount++;
116         }
117 }
118
119 /*
120  * Expects runqueue lock to be held for atomicity of update
121  */
122 static inline void
123 rq_sched_info_depart(struct rq *rq, unsigned long long delta)
124 {
125         if (rq)
126                 rq->rq_cpu_time += delta;
127 }
128
129 static inline void
130 rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
131 {
132         if (rq)
133                 rq->rq_sched_info.run_delay += delta;
134 }
135 # define schedstat_inc(rq, field)       do { (rq)->field++; } while (0)
136 # define schedstat_add(rq, field, amt)  do { (rq)->field += (amt); } while (0)
137 # define schedstat_set(var, val)        do { var = (val); } while (0)
138 #else /* !CONFIG_SCHEDSTATS */
139 static inline void
140 rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
141 {}
142 static inline void
143 rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
144 {}
145 static inline void
146 rq_sched_info_depart(struct rq *rq, unsigned long long delta)
147 {}
148 # define schedstat_inc(rq, field)       do { } while (0)
149 # define schedstat_add(rq, field, amt)  do { } while (0)
150 # define schedstat_set(var, val)        do { } while (0)
151 #endif
152
153 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
154 static inline void sched_info_reset_dequeued(struct task_struct *t)
155 {
156         t->sched_info.last_queued = 0;
157 }
158
159 /*
160  * We are interested in knowing how long it was from the *first* time a
161  * task was queued to the time that it finally hit a cpu, we call this routine
162  * from dequeue_task() to account for possible rq->clock skew across cpus. The
163  * delta taken on each cpu would annul the skew.
164  */
165 static inline void sched_info_dequeued(struct task_struct *t)
166 {
167         unsigned long long now = task_rq(t)->clock, delta = 0;
168
169         if (unlikely(sched_info_on()))
170                 if (t->sched_info.last_queued)
171                         delta = now - t->sched_info.last_queued;
172         sched_info_reset_dequeued(t);
173         t->sched_info.run_delay += delta;
174
175         rq_sched_info_dequeued(task_rq(t), delta);
176 }
177
178 /*
179  * Called when a task finally hits the cpu.  We can now calculate how
180  * long it was waiting to run.  We also note when it began so that we
181  * can keep stats on how long its timeslice is.
182  */
183 static void sched_info_arrive(struct task_struct *t)
184 {
185         unsigned long long now = task_rq(t)->clock, delta = 0;
186
187         if (t->sched_info.last_queued)
188                 delta = now - t->sched_info.last_queued;
189         sched_info_reset_dequeued(t);
190         t->sched_info.run_delay += delta;
191         t->sched_info.last_arrival = now;
192         t->sched_info.pcount++;
193
194         rq_sched_info_arrive(task_rq(t), delta);
195 }
196
197 /*
198  * This function is only called from enqueue_task(), but also only updates
199  * the timestamp if it is already not set.  It's assumed that
200  * sched_info_dequeued() will clear that stamp when appropriate.
201  */
202 static inline void sched_info_queued(struct task_struct *t)
203 {
204         if (unlikely(sched_info_on()))
205                 if (!t->sched_info.last_queued)
206                         t->sched_info.last_queued = task_rq(t)->clock;
207 }
208
209 /*
210  * Called when a process ceases being the active-running process, either
211  * voluntarily or involuntarily.  Now we can calculate how long we ran.
212  * Also, if the process is still in the TASK_RUNNING state, call
213  * sched_info_queued() to mark that it has now again started waiting on
214  * the runqueue.
215  */
216 static inline void sched_info_depart(struct task_struct *t)
217 {
218         unsigned long long delta = task_rq(t)->clock -
219                                         t->sched_info.last_arrival;
220
221         rq_sched_info_depart(task_rq(t), delta);
222
223         if (t->state == TASK_RUNNING)
224                 sched_info_queued(t);
225 }
226
227 /*
228  * Called when tasks are switched involuntarily due, typically, to expiring
229  * their time slice.  (This may also be called when switching to or from
230  * the idle task.)  We are only called when prev != next.
231  */
232 static inline void
233 __sched_info_switch(struct task_struct *prev, struct task_struct *next)
234 {
235         struct rq *rq = task_rq(prev);
236
237         /*
238          * prev now departs the cpu.  It's not interesting to record
239          * stats about how efficient we were at scheduling the idle
240          * process, however.
241          */
242         if (prev != rq->idle)
243                 sched_info_depart(prev);
244
245         if (next != rq->idle)
246                 sched_info_arrive(next);
247 }
248 static inline void
249 sched_info_switch(struct task_struct *prev, struct task_struct *next)
250 {
251         if (unlikely(sched_info_on()))
252                 __sched_info_switch(prev, next);
253 }
254 #else
255 #define sched_info_queued(t)                    do { } while (0)
256 #define sched_info_reset_dequeued(t)    do { } while (0)
257 #define sched_info_dequeued(t)                  do { } while (0)
258 #define sched_info_switch(t, next)              do { } while (0)
259 #endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */
260
261 /*
262  * The following are functions that support scheduler-internal time accounting.
263  * These functions are generally called at the timer tick.  None of this depends
264  * on CONFIG_SCHEDSTATS.
265  */
266
267 /**
268  * account_group_user_time - Maintain utime for a thread group.
269  *
270  * @tsk:        Pointer to task structure.
271  * @cputime:    Time value by which to increment the utime field of the
272  *              thread_group_cputime structure.
273  *
274  * If thread group time is being maintained, get the structure for the
275  * running CPU and update the utime field there.
276  */
277 static inline void account_group_user_time(struct task_struct *tsk,
278                                            cputime_t cputime)
279 {
280         struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
281
282         if (!cputimer->running)
283                 return;
284
285         spin_lock(&cputimer->lock);
286         cputimer->cputime.utime =
287                 cputime_add(cputimer->cputime.utime, cputime);
288         spin_unlock(&cputimer->lock);
289 }
290
291 /**
292  * account_group_system_time - Maintain stime for a thread group.
293  *
294  * @tsk:        Pointer to task structure.
295  * @cputime:    Time value by which to increment the stime field of the
296  *              thread_group_cputime structure.
297  *
298  * If thread group time is being maintained, get the structure for the
299  * running CPU and update the stime field there.
300  */
301 static inline void account_group_system_time(struct task_struct *tsk,
302                                              cputime_t cputime)
303 {
304         struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
305
306         if (!cputimer->running)
307                 return;
308
309         spin_lock(&cputimer->lock);
310         cputimer->cputime.stime =
311                 cputime_add(cputimer->cputime.stime, cputime);
312         spin_unlock(&cputimer->lock);
313 }
314
315 /**
316  * account_group_exec_runtime - Maintain exec runtime for a thread group.
317  *
318  * @tsk:        Pointer to task structure.
319  * @ns:         Time value by which to increment the sum_exec_runtime field
320  *              of the thread_group_cputime structure.
321  *
322  * If thread group time is being maintained, get the structure for the
323  * running CPU and update the sum_exec_runtime field there.
324  */
325 static inline void account_group_exec_runtime(struct task_struct *tsk,
326                                               unsigned long long ns)
327 {
328         struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
329
330         if (!cputimer->running)
331                 return;
332
333         spin_lock(&cputimer->lock);
334         cputimer->cputime.sum_exec_runtime += ns;
335         spin_unlock(&cputimer->lock);
336 }