Merge branch 'akpm' (patches from Andrew)
[sfrench/cifs-2.6.git] / fs / proc / stat.c
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);