xref: /openbmc/linux/kernel/sched/stats.c (revision 95e9fd10)
1 
2 #include <linux/slab.h>
3 #include <linux/fs.h>
4 #include <linux/seq_file.h>
5 #include <linux/proc_fs.h>
6 
7 #include "sched.h"
8 
9 /*
10  * bump this up when changing the output format or the meaning of an existing
11  * format, so that tools can adapt (or abort)
12  */
13 #define SCHEDSTAT_VERSION 15
14 
15 static int show_schedstat(struct seq_file *seq, void *v)
16 {
17 	int cpu;
18 	int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9;
19 	char *mask_str = kmalloc(mask_len, GFP_KERNEL);
20 
21 	if (mask_str == NULL)
22 		return -ENOMEM;
23 
24 	seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION);
25 	seq_printf(seq, "timestamp %lu\n", jiffies);
26 	for_each_online_cpu(cpu) {
27 		struct rq *rq = cpu_rq(cpu);
28 #ifdef CONFIG_SMP
29 		struct sched_domain *sd;
30 		int dcount = 0;
31 #endif
32 
33 		/* runqueue-specific stats */
34 		seq_printf(seq,
35 		    "cpu%d %u 0 %u %u %u %u %llu %llu %lu",
36 		    cpu, rq->yld_count,
37 		    rq->sched_count, rq->sched_goidle,
38 		    rq->ttwu_count, rq->ttwu_local,
39 		    rq->rq_cpu_time,
40 		    rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
41 
42 		seq_printf(seq, "\n");
43 
44 #ifdef CONFIG_SMP
45 		/* domain-specific stats */
46 		rcu_read_lock();
47 		for_each_domain(cpu, sd) {
48 			enum cpu_idle_type itype;
49 
50 			cpumask_scnprintf(mask_str, mask_len,
51 					  sched_domain_span(sd));
52 			seq_printf(seq, "domain%d %s", dcount++, mask_str);
53 			for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
54 					itype++) {
55 				seq_printf(seq, " %u %u %u %u %u %u %u %u",
56 				    sd->lb_count[itype],
57 				    sd->lb_balanced[itype],
58 				    sd->lb_failed[itype],
59 				    sd->lb_imbalance[itype],
60 				    sd->lb_gained[itype],
61 				    sd->lb_hot_gained[itype],
62 				    sd->lb_nobusyq[itype],
63 				    sd->lb_nobusyg[itype]);
64 			}
65 			seq_printf(seq,
66 				   " %u %u %u %u %u %u %u %u %u %u %u %u\n",
67 			    sd->alb_count, sd->alb_failed, sd->alb_pushed,
68 			    sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed,
69 			    sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed,
70 			    sd->ttwu_wake_remote, sd->ttwu_move_affine,
71 			    sd->ttwu_move_balance);
72 		}
73 		rcu_read_unlock();
74 #endif
75 	}
76 	kfree(mask_str);
77 	return 0;
78 }
79 
80 static int schedstat_open(struct inode *inode, struct file *file)
81 {
82 	unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32);
83 	char *buf = kmalloc(size, GFP_KERNEL);
84 	struct seq_file *m;
85 	int res;
86 
87 	if (!buf)
88 		return -ENOMEM;
89 	res = single_open(file, show_schedstat, NULL);
90 	if (!res) {
91 		m = file->private_data;
92 		m->buf = buf;
93 		m->size = size;
94 	} else
95 		kfree(buf);
96 	return res;
97 }
98 
99 static const struct file_operations proc_schedstat_operations = {
100 	.open    = schedstat_open,
101 	.read    = seq_read,
102 	.llseek  = seq_lseek,
103 	.release = single_release,
104 };
105 
106 static int __init proc_schedstat_init(void)
107 {
108 	proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
109 	return 0;
110 }
111 module_init(proc_schedstat_init);
112