1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/cpumask.h> 3 #include <linux/fs.h> 4 #include <linux/init.h> 5 #include <linux/interrupt.h> 6 #include <linux/kernel_stat.h> 7 #include <linux/proc_fs.h> 8 #include <linux/sched.h> 9 #include <linux/sched/stat.h> 10 #include <linux/seq_file.h> 11 #include <linux/slab.h> 12 #include <linux/time.h> 13 #include <linux/irqnr.h> 14 #include <linux/sched/cputime.h> 15 #include <linux/tick.h> 16 17 #ifndef arch_irq_stat_cpu 18 #define arch_irq_stat_cpu(cpu) 0 19 #endif 20 #ifndef arch_irq_stat 21 #define arch_irq_stat() 0 22 #endif 23 24 #ifdef arch_idle_time 25 26 static u64 get_idle_time(struct kernel_cpustat *kcs, int cpu) 27 { 28 u64 idle; 29 30 idle = kcs->cpustat[CPUTIME_IDLE]; 31 if (cpu_online(cpu) && !nr_iowait_cpu(cpu)) 32 idle += arch_idle_time(cpu); 33 return idle; 34 } 35 36 static u64 get_iowait_time(struct kernel_cpustat *kcs, int cpu) 37 { 38 u64 iowait; 39 40 iowait = kcs->cpustat[CPUTIME_IOWAIT]; 41 if (cpu_online(cpu) && nr_iowait_cpu(cpu)) 42 iowait += arch_idle_time(cpu); 43 return iowait; 44 } 45 46 #else 47 48 static u64 get_idle_time(struct kernel_cpustat *kcs, int cpu) 49 { 50 u64 idle, idle_usecs = -1ULL; 51 52 if (cpu_online(cpu)) 53 idle_usecs = get_cpu_idle_time_us(cpu, NULL); 54 55 if (idle_usecs == -1ULL) 56 /* !NO_HZ or cpu offline so we can rely on cpustat.idle */ 57 idle = kcs->cpustat[CPUTIME_IDLE]; 58 else 59 idle = idle_usecs * NSEC_PER_USEC; 60 61 return idle; 62 } 63 64 static u64 get_iowait_time(struct kernel_cpustat *kcs, int cpu) 65 { 66 u64 iowait, iowait_usecs = -1ULL; 67 68 if (cpu_online(cpu)) 69 iowait_usecs = get_cpu_iowait_time_us(cpu, NULL); 70 71 if (iowait_usecs == -1ULL) 72 /* !NO_HZ or cpu offline so we can rely on cpustat.iowait */ 73 iowait = kcs->cpustat[CPUTIME_IOWAIT]; 74 else 75 iowait = iowait_usecs * NSEC_PER_USEC; 76 77 return iowait; 78 } 79 80 #endif 81 82 static void show_irq_gap(struct seq_file *p, unsigned int gap) 83 { 84 static const char zeros[] = " 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0"; 85 86 while (gap > 0) { 87 unsigned int inc; 88 89 inc = min_t(unsigned int, gap, ARRAY_SIZE(zeros) / 2); 90 seq_write(p, zeros, 2 * inc); 91 gap -= inc; 92 } 93 } 94 95 static void show_all_irqs(struct seq_file *p) 96 { 97 unsigned int i, next = 0; 98 99 for_each_active_irq(i) { 100 show_irq_gap(p, i - next); 101 seq_put_decimal_ull(p, " ", kstat_irqs_usr(i)); 102 next = i + 1; 103 } 104 show_irq_gap(p, nr_irqs - next); 105 } 106 107 static int show_stat(struct seq_file *p, void *v) 108 { 109 int i, j; 110 u64 user, nice, system, idle, iowait, irq, softirq, steal; 111 u64 guest, guest_nice; 112 u64 sum = 0; 113 u64 sum_softirq = 0; 114 unsigned int per_softirq_sums[NR_SOFTIRQS] = {0}; 115 struct timespec64 boottime; 116 117 user = nice = system = idle = iowait = 118 irq = softirq = steal = 0; 119 guest = guest_nice = 0; 120 getboottime64(&boottime); 121 122 for_each_possible_cpu(i) { 123 struct kernel_cpustat *kcs = &kcpustat_cpu(i); 124 125 user += kcs->cpustat[CPUTIME_USER]; 126 nice += kcs->cpustat[CPUTIME_NICE]; 127 system += kcs->cpustat[CPUTIME_SYSTEM]; 128 idle += get_idle_time(kcs, i); 129 iowait += get_iowait_time(kcs, i); 130 irq += kcs->cpustat[CPUTIME_IRQ]; 131 softirq += kcs->cpustat[CPUTIME_SOFTIRQ]; 132 steal += kcs->cpustat[CPUTIME_STEAL]; 133 guest += kcs->cpustat[CPUTIME_GUEST]; 134 guest_nice += kcs->cpustat[CPUTIME_GUEST_NICE]; 135 sum += kstat_cpu_irqs_sum(i); 136 sum += arch_irq_stat_cpu(i); 137 138 for (j = 0; j < NR_SOFTIRQS; j++) { 139 unsigned int softirq_stat = kstat_softirqs_cpu(j, i); 140 141 per_softirq_sums[j] += softirq_stat; 142 sum_softirq += softirq_stat; 143 } 144 } 145 sum += arch_irq_stat(); 146 147 seq_put_decimal_ull(p, "cpu ", nsec_to_clock_t(user)); 148 seq_put_decimal_ull(p, " ", nsec_to_clock_t(nice)); 149 seq_put_decimal_ull(p, " ", nsec_to_clock_t(system)); 150 seq_put_decimal_ull(p, " ", nsec_to_clock_t(idle)); 151 seq_put_decimal_ull(p, " ", nsec_to_clock_t(iowait)); 152 seq_put_decimal_ull(p, " ", nsec_to_clock_t(irq)); 153 seq_put_decimal_ull(p, " ", nsec_to_clock_t(softirq)); 154 seq_put_decimal_ull(p, " ", nsec_to_clock_t(steal)); 155 seq_put_decimal_ull(p, " ", nsec_to_clock_t(guest)); 156 seq_put_decimal_ull(p, " ", nsec_to_clock_t(guest_nice)); 157 seq_putc(p, '\n'); 158 159 for_each_online_cpu(i) { 160 struct kernel_cpustat *kcs = &kcpustat_cpu(i); 161 162 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */ 163 user = kcs->cpustat[CPUTIME_USER]; 164 nice = kcs->cpustat[CPUTIME_NICE]; 165 system = kcs->cpustat[CPUTIME_SYSTEM]; 166 idle = get_idle_time(kcs, i); 167 iowait = get_iowait_time(kcs, i); 168 irq = kcs->cpustat[CPUTIME_IRQ]; 169 softirq = kcs->cpustat[CPUTIME_SOFTIRQ]; 170 steal = kcs->cpustat[CPUTIME_STEAL]; 171 guest = kcs->cpustat[CPUTIME_GUEST]; 172 guest_nice = kcs->cpustat[CPUTIME_GUEST_NICE]; 173 seq_printf(p, "cpu%d", i); 174 seq_put_decimal_ull(p, " ", nsec_to_clock_t(user)); 175 seq_put_decimal_ull(p, " ", nsec_to_clock_t(nice)); 176 seq_put_decimal_ull(p, " ", nsec_to_clock_t(system)); 177 seq_put_decimal_ull(p, " ", nsec_to_clock_t(idle)); 178 seq_put_decimal_ull(p, " ", nsec_to_clock_t(iowait)); 179 seq_put_decimal_ull(p, " ", nsec_to_clock_t(irq)); 180 seq_put_decimal_ull(p, " ", nsec_to_clock_t(softirq)); 181 seq_put_decimal_ull(p, " ", nsec_to_clock_t(steal)); 182 seq_put_decimal_ull(p, " ", nsec_to_clock_t(guest)); 183 seq_put_decimal_ull(p, " ", nsec_to_clock_t(guest_nice)); 184 seq_putc(p, '\n'); 185 } 186 seq_put_decimal_ull(p, "intr ", (unsigned long long)sum); 187 188 show_all_irqs(p); 189 190 seq_printf(p, 191 "\nctxt %llu\n" 192 "btime %llu\n" 193 "processes %lu\n" 194 "procs_running %lu\n" 195 "procs_blocked %lu\n", 196 nr_context_switches(), 197 (unsigned long long)boottime.tv_sec, 198 total_forks, 199 nr_running(), 200 nr_iowait()); 201 202 seq_put_decimal_ull(p, "softirq ", (unsigned long long)sum_softirq); 203 204 for (i = 0; i < NR_SOFTIRQS; i++) 205 seq_put_decimal_ull(p, " ", per_softirq_sums[i]); 206 seq_putc(p, '\n'); 207 208 return 0; 209 } 210 211 static int stat_open(struct inode *inode, struct file *file) 212 { 213 unsigned int size = 1024 + 128 * num_online_cpus(); 214 215 /* minimum size to display an interrupt count : 2 bytes */ 216 size += 2 * nr_irqs; 217 return single_open_size(file, show_stat, NULL, size); 218 } 219 220 static const struct file_operations proc_stat_operations = { 221 .open = stat_open, 222 .read = seq_read, 223 .llseek = seq_lseek, 224 .release = single_release, 225 }; 226 227 static int __init proc_stat_init(void) 228 { 229 proc_create("stat", 0, NULL, &proc_stat_operations); 230 return 0; 231 } 232 fs_initcall(proc_stat_init); 233