1 /* vi: set sw=4 ts=4: */
2 /*
3 * Report CPU and I/O stats, based on sysstat version 9.1.2 by Sebastien Godard
4 *
5 * Copyright (C) 2010 Marek Polacek <mmpolacek@gmail.com>
6 *
7 * Licensed under GPLv2, see file LICENSE in this source tree.
8 */
9
10 //config:config IOSTAT
11 //config: bool "iostat"
12 //config: default y
13 //config: help
14 //config: Report CPU and I/O statistics
15
16 //applet:IF_IOSTAT(APPLET(iostat, BB_DIR_BIN, BB_SUID_DROP))
17
18 //kbuild:lib-$(CONFIG_IOSTAT) += iostat.o
19
20 #include "libbb.h"
21 #include <sys/utsname.h> /* struct utsname */
22
23 //#define debug(fmt, ...) fprintf(stderr, fmt, ## __VA_ARGS__)
24 #define debug(fmt, ...) ((void)0)
25
26 #define MAX_DEVICE_NAME 12
27 #define MAX_DEVICE_NAME_STR "12"
28
29 #if 1
30 typedef unsigned long long cputime_t;
31 typedef long long icputime_t;
32 # define FMT_DATA "ll"
33 # define CPUTIME_MAX (~0ULL)
34 #else
35 typedef unsigned long cputime_t;
36 typedef long icputime_t;
37 # define FMT_DATA "l"
38 # define CPUTIME_MAX (~0UL)
39 #endif
40
41 enum {
42 STATS_CPU_USER,
43 STATS_CPU_NICE,
44 STATS_CPU_SYSTEM,
45 STATS_CPU_IDLE,
46 STATS_CPU_IOWAIT,
47 STATS_CPU_IRQ,
48 STATS_CPU_SOFTIRQ,
49 STATS_CPU_STEAL,
50 STATS_CPU_GUEST,
51
52 GLOBAL_UPTIME,
53 SMP_UPTIME,
54
55 N_STATS_CPU,
56 };
57
58 typedef struct {
59 cputime_t vector[N_STATS_CPU];
60 } stats_cpu_t;
61
62 typedef struct {
63 stats_cpu_t *prev;
64 stats_cpu_t *curr;
65 cputime_t itv;
66 } stats_cpu_pair_t;
67
68 typedef struct {
69 unsigned long long rd_sectors;
70 unsigned long long wr_sectors;
71 unsigned long rd_ops;
72 unsigned long wr_ops;
73 } stats_dev_data_t;
74
75 typedef struct stats_dev {
76 struct stats_dev *next;
77 char dname[MAX_DEVICE_NAME + 1];
78 stats_dev_data_t prev_data;
79 stats_dev_data_t curr_data;
80 } stats_dev_t;
81
82 /* Globals. Sort by size and access frequency. */
83 struct globals {
84 smallint show_all;
85 unsigned total_cpus; /* Number of CPUs */
86 unsigned clk_tck; /* Number of clock ticks per second */
87 llist_t *dev_name_list; /* List of devices entered on the command line */
88 stats_dev_t *stats_dev_list;
89 struct tm tmtime;
90 struct {
91 const char *str;
92 unsigned div;
93 } unit;
94 };
95 #define G (*ptr_to_globals)
96 #define INIT_G() do { \
97 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
98 G.unit.str = "Blk"; \
99 G.unit.div = 1; \
100 } while (0)
101
102 /* Must match option string! */
103 enum {
104 OPT_c = 1 << 0,
105 OPT_d = 1 << 1,
106 OPT_t = 1 << 2,
107 OPT_z = 1 << 3,
108 OPT_k = 1 << 4,
109 OPT_m = 1 << 5,
110 };
111
this_is_smp(void)112 static ALWAYS_INLINE int this_is_smp(void)
113 {
114 return (G.total_cpus > 1);
115 }
116
print_header(void)117 static void print_header(void)
118 {
119 char buf[32];
120 struct utsname uts;
121
122 uname(&uts); /* never fails */
123
124 /* Date representation for the current locale */
125 strftime(buf, sizeof(buf), "%x", &G.tmtime);
126
127 printf("%s %s (%s) \t%s \t_%s_\t(%u CPU)\n\n",
128 uts.sysname, uts.release, uts.nodename,
129 buf, uts.machine, G.total_cpus);
130 }
131
get_localtime(struct tm * ptm)132 static void get_localtime(struct tm *ptm)
133 {
134 time_t timer;
135 time(&timer);
136 localtime_r(&timer, ptm);
137 }
138
print_timestamp(void)139 static void print_timestamp(void)
140 {
141 char buf[64];
142 /* %x: date representation for the current locale */
143 /* %X: time representation for the current locale */
144 strftime(buf, sizeof(buf), "%x %X", &G.tmtime);
145 puts(buf);
146 }
147
get_smp_uptime(void)148 static cputime_t get_smp_uptime(void)
149 {
150 FILE *fp;
151 unsigned long sec, dec;
152
153 fp = xfopen_for_read("/proc/uptime");
154
155 if (fscanf(fp, "%lu.%lu", &sec, &dec) != 2)
156 bb_error_msg_and_die("can't read '%s'", "/proc/uptime");
157
158 fclose(fp);
159
160 return (cputime_t)sec * G.clk_tck + dec * G.clk_tck / 100;
161 }
162
163 /* Fetch CPU statistics from /proc/stat */
get_cpu_statistics(stats_cpu_t * sc)164 static void get_cpu_statistics(stats_cpu_t *sc)
165 {
166 FILE *fp;
167 char buf[1024];
168
169 fp = xfopen_for_read("/proc/stat");
170
171 memset(sc, 0, sizeof(*sc));
172
173 while (fgets(buf, sizeof(buf), fp)) {
174 int i;
175 char *ibuf;
176
177 /* Does the line start with "cpu "? */
178 if (!starts_with_cpu(buf) || buf[3] != ' ') {
179 continue;
180 }
181 ibuf = buf + 4;
182 for (i = STATS_CPU_USER; i <= STATS_CPU_GUEST; i++) {
183 ibuf = skip_whitespace(ibuf);
184 sscanf(ibuf, "%"FMT_DATA"u", &sc->vector[i]);
185 if (i != STATS_CPU_GUEST) {
186 sc->vector[GLOBAL_UPTIME] += sc->vector[i];
187 }
188 ibuf = skip_non_whitespace(ibuf);
189 }
190 break;
191 }
192
193 if (this_is_smp()) {
194 sc->vector[SMP_UPTIME] = get_smp_uptime();
195 }
196
197 fclose(fp);
198 }
199
get_interval(cputime_t old,cputime_t new)200 static ALWAYS_INLINE cputime_t get_interval(cputime_t old, cputime_t new)
201 {
202 cputime_t itv = new - old;
203
204 return (itv == 0) ? 1 : itv;
205 }
206
207 #if CPUTIME_MAX > 0xffffffff
208 /*
209 * Handle overflow conditions properly for counters which can have
210 * less bits than cputime_t, depending on the kernel version.
211 */
212 /* Surprisingly, on 32bit inlining is a size win */
overflow_safe_sub(cputime_t prev,cputime_t curr)213 static ALWAYS_INLINE cputime_t overflow_safe_sub(cputime_t prev, cputime_t curr)
214 {
215 cputime_t v = curr - prev;
216
217 if ((icputime_t)v < 0 /* curr < prev - counter overflow? */
218 && prev <= 0xffffffff /* kernel uses 32bit value for the counter? */
219 ) {
220 /* Add 33th bit set to 1 to curr, compensating for the overflow */
221 /* double shift defeats "warning: left shift count >= width of type" */
222 v += ((cputime_t)1 << 16) << 16;
223 }
224 return v;
225 }
226 #else
overflow_safe_sub(cputime_t prev,cputime_t curr)227 static ALWAYS_INLINE cputime_t overflow_safe_sub(cputime_t prev, cputime_t curr)
228 {
229 return curr - prev;
230 }
231 #endif
232
percent_value(cputime_t prev,cputime_t curr,cputime_t itv)233 static double percent_value(cputime_t prev, cputime_t curr, cputime_t itv)
234 {
235 return ((double)overflow_safe_sub(prev, curr)) / itv * 100;
236 }
237
print_stats_cpu_struct(stats_cpu_pair_t * stats)238 static void print_stats_cpu_struct(stats_cpu_pair_t *stats)
239 {
240 cputime_t *p = stats->prev->vector;
241 cputime_t *c = stats->curr->vector;
242 printf(" %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f\n",
243 percent_value(p[STATS_CPU_USER] , c[STATS_CPU_USER] , stats->itv),
244 percent_value(p[STATS_CPU_NICE] , c[STATS_CPU_NICE] , stats->itv),
245 percent_value(p[STATS_CPU_SYSTEM] + p[STATS_CPU_SOFTIRQ] + p[STATS_CPU_IRQ],
246 c[STATS_CPU_SYSTEM] + c[STATS_CPU_SOFTIRQ] + c[STATS_CPU_IRQ], stats->itv),
247 percent_value(p[STATS_CPU_IOWAIT], c[STATS_CPU_IOWAIT], stats->itv),
248 percent_value(p[STATS_CPU_STEAL] , c[STATS_CPU_STEAL] , stats->itv),
249 percent_value(p[STATS_CPU_IDLE] , c[STATS_CPU_IDLE] , stats->itv)
250 );
251 }
252
cpu_report(stats_cpu_pair_t * stats)253 static void cpu_report(stats_cpu_pair_t *stats)
254 {
255 /* Always print a header */
256 puts("avg-cpu: %user %nice %system %iowait %steal %idle");
257
258 /* Print current statistics */
259 print_stats_cpu_struct(stats);
260 }
261
print_stats_dev_struct(stats_dev_t * stats_dev,cputime_t itv)262 static void print_stats_dev_struct(stats_dev_t *stats_dev, cputime_t itv)
263 {
264 stats_dev_data_t *p = &stats_dev->prev_data;
265 stats_dev_data_t *c = &stats_dev->curr_data;
266 if (option_mask32 & OPT_z)
267 if (p->rd_ops == c->rd_ops && p->wr_ops == c->wr_ops)
268 return;
269
270 printf("%-13s %8.2f %12.2f %12.2f %10llu %10llu\n",
271 stats_dev->dname,
272 percent_value(p->rd_ops + p->wr_ops, c->rd_ops + c->wr_ops, itv),
273 percent_value(p->rd_sectors, c->rd_sectors, itv) / G.unit.div,
274 percent_value(p->wr_sectors, c->wr_sectors, itv) / G.unit.div,
275 (c->rd_sectors - p->rd_sectors) / G.unit.div,
276 (c->wr_sectors - p->wr_sectors) / G.unit.div
277 );
278 }
279
print_devstat_header(void)280 static void print_devstat_header(void)
281 {
282 printf("Device:%15s%6s%s/s%6s%s/s%6s%s%6s%s\n",
283 "tps",
284 G.unit.str, "_read", G.unit.str, "_wrtn",
285 G.unit.str, "_read", G.unit.str, "_wrtn"
286 );
287 }
288
289 /*
290 * Is input partition of format [sdaN]?
291 */
is_partition(const char * dev)292 static int is_partition(const char *dev)
293 {
294 /* Ok, this is naive... */
295 return ((dev[0] - 's') | (dev[1] - 'd') | (dev[2] - 'a')) == 0 && isdigit(dev[3]);
296 }
297
stats_dev_find_or_new(const char * dev_name)298 static stats_dev_t *stats_dev_find_or_new(const char *dev_name)
299 {
300 stats_dev_t **curr = &G.stats_dev_list;
301
302 while (*curr != NULL) {
303 if (strcmp((*curr)->dname, dev_name) == 0)
304 return *curr;
305 curr = &(*curr)->next;
306 }
307
308 *curr = xzalloc(sizeof(stats_dev_t));
309 strncpy((*curr)->dname, dev_name, MAX_DEVICE_NAME);
310 return *curr;
311 }
312
stats_dev_free(stats_dev_t * stats_dev)313 static void stats_dev_free(stats_dev_t *stats_dev)
314 {
315 if (stats_dev) {
316 stats_dev_free(stats_dev->next);
317 free(stats_dev);
318 }
319 }
320
do_disk_statistics(cputime_t itv)321 static void do_disk_statistics(cputime_t itv)
322 {
323 char buf[128];
324 char dev_name[MAX_DEVICE_NAME + 1];
325 unsigned long long rd_sec_or_dummy;
326 unsigned long long wr_sec_or_dummy;
327 stats_dev_data_t *curr_data;
328 stats_dev_t *stats_dev;
329 FILE *fp;
330 int rc;
331
332 fp = xfopen_for_read("/proc/diskstats");
333 /* Read and possibly print stats from /proc/diskstats */
334 while (fgets(buf, sizeof(buf), fp)) {
335 sscanf(buf, "%*s %*s %"MAX_DEVICE_NAME_STR"s", dev_name);
336 if (G.dev_name_list) {
337 /* Is device name in list? */
338 if (!llist_find_str(G.dev_name_list, dev_name))
339 continue;
340 } else if (is_partition(dev_name)) {
341 continue;
342 }
343
344 stats_dev = stats_dev_find_or_new(dev_name);
345 curr_data = &stats_dev->curr_data;
346
347 rc = sscanf(buf, "%*s %*s %*s %lu %llu %llu %llu %lu %*s %llu",
348 &curr_data->rd_ops,
349 &rd_sec_or_dummy,
350 &curr_data->rd_sectors,
351 &wr_sec_or_dummy,
352 &curr_data->wr_ops,
353 &curr_data->wr_sectors);
354 if (rc != 6) {
355 curr_data->rd_sectors = rd_sec_or_dummy;
356 curr_data->wr_sectors = wr_sec_or_dummy;
357 //curr_data->rd_ops = ;
358 curr_data->wr_ops = (unsigned long)curr_data->rd_sectors;
359 }
360
361 if (!G.dev_name_list /* User didn't specify device */
362 && !G.show_all
363 && curr_data->rd_ops == 0
364 && curr_data->wr_ops == 0
365 ) {
366 /* Don't print unused device */
367 continue;
368 }
369
370 /* Print current statistics */
371 print_stats_dev_struct(stats_dev, itv);
372 stats_dev->prev_data = *curr_data;
373 }
374
375 fclose(fp);
376 }
377
dev_report(cputime_t itv)378 static void dev_report(cputime_t itv)
379 {
380 /* Always print a header */
381 print_devstat_header();
382
383 /* Fetch current disk statistics */
384 do_disk_statistics(itv);
385 }
386
387 //usage:#define iostat_trivial_usage
388 //usage: "[-c] [-d] [-t] [-z] [-k|-m] [ALL|BLOCKDEV...] [INTERVAL [COUNT]]"
389 //usage:#define iostat_full_usage "\n\n"
390 //usage: "Report CPU and I/O statistics\n"
391 //usage: "\n -c Show CPU utilization"
392 //usage: "\n -d Show device utilization"
393 //usage: "\n -t Print current time"
394 //usage: "\n -z Omit devices with no activity"
395 //usage: "\n -k Use kb/s"
396 //usage: "\n -m Use Mb/s"
397
398 int iostat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
iostat_main(int argc UNUSED_PARAM,char ** argv)399 int iostat_main(int argc UNUSED_PARAM, char **argv)
400 {
401 int opt;
402 unsigned interval;
403 int count;
404 stats_cpu_t stats_data[2];
405 smallint current_stats;
406
407 INIT_G();
408
409 memset(&stats_data, 0, sizeof(stats_data));
410
411 /* Get number of clock ticks per sec */
412 G.clk_tck = bb_clk_tck();
413
414 /* Determine number of CPUs */
415 G.total_cpus = get_cpu_count();
416 if (G.total_cpus == 0)
417 G.total_cpus = 1;
418
419 /* Parse and process arguments */
420 /* -k and -m are mutually exclusive */
421 opt_complementary = "k--m:m--k";
422 opt = getopt32(argv, "cdtzkm");
423 if (!(opt & (OPT_c + OPT_d)))
424 /* Default is -cd */
425 opt |= OPT_c + OPT_d;
426
427 argv += optind;
428
429 /* Store device names into device list */
430 while (*argv && !isdigit(*argv[0])) {
431 if (strcmp(*argv, "ALL") != 0) {
432 /* If not ALL, save device name */
433 char *dev_name = skip_dev_pfx(*argv);
434 if (!llist_find_str(G.dev_name_list, dev_name)) {
435 llist_add_to(&G.dev_name_list, dev_name);
436 }
437 } else {
438 G.show_all = 1;
439 }
440 argv++;
441 }
442
443 interval = 0;
444 count = 1;
445 if (*argv) {
446 /* Get interval */
447 interval = xatoi_positive(*argv);
448 count = (interval != 0 ? -1 : 1);
449 argv++;
450 if (*argv)
451 /* Get count value */
452 count = xatoi_positive(*argv);
453 }
454
455 if (opt & OPT_m) {
456 G.unit.str = " MB";
457 G.unit.div = 2048;
458 }
459
460 if (opt & OPT_k) {
461 G.unit.str = " kB";
462 G.unit.div = 2;
463 }
464
465 get_localtime(&G.tmtime);
466
467 /* Display header */
468 print_header();
469
470 current_stats = 0;
471 /* Main loop */
472 for (;;) {
473 stats_cpu_pair_t stats;
474
475 stats.prev = &stats_data[current_stats ^ 1];
476 stats.curr = &stats_data[current_stats];
477
478 /* Fill the time structure */
479 get_localtime(&G.tmtime);
480
481 /* Fetch current CPU statistics */
482 get_cpu_statistics(stats.curr);
483
484 /* Get interval */
485 stats.itv = get_interval(
486 stats.prev->vector[GLOBAL_UPTIME],
487 stats.curr->vector[GLOBAL_UPTIME]
488 );
489
490 if (opt & OPT_t)
491 print_timestamp();
492
493 if (opt & OPT_c) {
494 cpu_report(&stats);
495 if (opt & OPT_d)
496 /* Separate outputs by a newline */
497 bb_putchar('\n');
498 }
499
500 if (opt & OPT_d) {
501 if (this_is_smp()) {
502 stats.itv = get_interval(
503 stats.prev->vector[SMP_UPTIME],
504 stats.curr->vector[SMP_UPTIME]
505 );
506 }
507 dev_report(stats.itv);
508 }
509
510 bb_putchar('\n');
511
512 if (count > 0) {
513 if (--count == 0)
514 break;
515 }
516
517 /* Swap stats */
518 current_stats ^= 1;
519
520 sleep(interval);
521 }
522
523 if (ENABLE_FEATURE_CLEAN_UP) {
524 llist_free(G.dev_name_list, NULL);
525 stats_dev_free(G.stats_dev_list);
526 free(&G);
527 }
528
529 return EXIT_SUCCESS;
530 }
531