1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/slab.h> 4 #include <linux/fs.h> 5 #include <linux/seq_file.h> 6 #include <linux/proc_fs.h> 7 8 #include "sched.h" 9 10 /* 11 * bump this up when changing the output format or the meaning of an existing 12 * format, so that tools can adapt (or abort) 13 */ 14 #define SCHEDSTAT_VERSION 15 15 16 static int show_schedstat(struct seq_file *seq, void *v) 17 { 18 int cpu; 19 20 if (v == (void *)1) { 21 seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION); 22 seq_printf(seq, "timestamp %lu\n", jiffies); 23 } else { 24 struct rq *rq; 25 #ifdef CONFIG_SMP 26 struct sched_domain *sd; 27 int dcount = 0; 28 #endif 29 cpu = (unsigned long)(v - 2); 30 rq = cpu_rq(cpu); 31 32 /* runqueue-specific stats */ 33 seq_printf(seq, 34 "cpu%d %u 0 %u %u %u %u %llu %llu %lu", 35 cpu, rq->yld_count, 36 rq->sched_count, rq->sched_goidle, 37 rq->ttwu_count, rq->ttwu_local, 38 rq->rq_cpu_time, 39 rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount); 40 41 seq_printf(seq, "\n"); 42 43 #ifdef CONFIG_SMP 44 /* domain-specific stats */ 45 rcu_read_lock(); 46 for_each_domain(cpu, sd) { 47 enum cpu_idle_type itype; 48 49 seq_printf(seq, "domain%d %*pb", dcount++, 50 cpumask_pr_args(sched_domain_span(sd))); 51 for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES; 52 itype++) { 53 seq_printf(seq, " %u %u %u %u %u %u %u %u", 54 sd->lb_count[itype], 55 sd->lb_balanced[itype], 56 sd->lb_failed[itype], 57 sd->lb_imbalance[itype], 58 sd->lb_gained[itype], 59 sd->lb_hot_gained[itype], 60 sd->lb_nobusyq[itype], 61 sd->lb_nobusyg[itype]); 62 } 63 seq_printf(seq, 64 " %u %u %u %u %u %u %u %u %u %u %u %u\n", 65 sd->alb_count, sd->alb_failed, sd->alb_pushed, 66 sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed, 67 sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed, 68 sd->ttwu_wake_remote, sd->ttwu_move_affine, 69 sd->ttwu_move_balance); 70 } 71 rcu_read_unlock(); 72 #endif 73 } 74 return 0; 75 } 76 77 /* 78 * This itererator needs some explanation. 79 * It returns 1 for the header position. 80 * This means 2 is cpu 0. 81 * In a hotplugged system some cpus, including cpu 0, may be missing so we have 82 * to use cpumask_* to iterate over the cpus. 83 */ 84 static void *schedstat_start(struct seq_file *file, loff_t *offset) 85 { 86 unsigned long n = *offset; 87 88 if (n == 0) 89 return (void *) 1; 90 91 n--; 92 93 if (n > 0) 94 n = cpumask_next(n - 1, cpu_online_mask); 95 else 96 n = cpumask_first(cpu_online_mask); 97 98 *offset = n + 1; 99 100 if (n < nr_cpu_ids) 101 return (void *)(unsigned long)(n + 2); 102 return NULL; 103 } 104 105 static void *schedstat_next(struct seq_file *file, void *data, loff_t *offset) 106 { 107 (*offset)++; 108 return schedstat_start(file, offset); 109 } 110 111 static void schedstat_stop(struct seq_file *file, void *data) 112 { 113 } 114 115 static const struct seq_operations schedstat_sops = { 116 .start = schedstat_start, 117 .next = schedstat_next, 118 .stop = schedstat_stop, 119 .show = show_schedstat, 120 }; 121 122 static int schedstat_open(struct inode *inode, struct file *file) 123 { 124 return seq_open(file, &schedstat_sops); 125 } 126 127 static const struct file_operations proc_schedstat_operations = { 128 .open = schedstat_open, 129 .read = seq_read, 130 .llseek = seq_lseek, 131 .release = seq_release, 132 }; 133 134 static int __init proc_schedstat_init(void) 135 { 136 proc_create("schedstat", 0, NULL, &proc_schedstat_operations); 137 return 0; 138 } 139 subsys_initcall(proc_schedstat_init); 140