blob: 06a33eb1d7b95b10372d223ecba60042eb7cae47 [file] [log] [blame]
Marek Polacek733f26f2010-08-11 17:00:59 +02001/* 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 *
Denys Vlasenko0ef64bd2010-08-16 20:14:46 +02007 * Licensed under GPLv2, see file LICENSE in this source tree.
Marek Polacek733f26f2010-08-11 17:00:59 +02008 */
9
Denys Vlasenkob9f2d9f2011-01-18 13:58:01 +010010//applet:IF_IOSTAT(APPLET(iostat, BB_DIR_BIN, BB_SUID_DROP))
Marek Polacek733f26f2010-08-11 17:00:59 +020011
12//kbuild:lib-$(CONFIG_IOSTAT) += iostat.o
13
14//config:config IOSTAT
15//config: bool "iostat"
16//config: default y
17//config: help
18//config: Report CPU and I/O statistics
19
20#include "libbb.h"
Denys Vlasenkofb132e42010-10-29 11:46:52 +020021#include <sys/utsname.h> /* Need struct utsname */
Marek Polacek733f26f2010-08-11 17:00:59 +020022
Denys Vlasenkodcaed972010-08-12 15:36:34 +020023//#define debug(fmt, ...) fprintf(stderr, fmt, ## __VA_ARGS__)
24#define debug(fmt, ...) ((void)0)
Marek Polacek733f26f2010-08-11 17:00:59 +020025
Denys Vlasenkofb132e42010-10-29 11:46:52 +020026#define MAX_DEVICE_NAME 12
27#define CURRENT 0
28#define LAST 1
Marek Polacek733f26f2010-08-11 17:00:59 +020029
30#if 1
31typedef unsigned long long cputime_t;
32typedef long long icputime_t;
33# define FMT_DATA "ll"
34# define CPUTIME_MAX (~0ULL)
35#else
36typedef unsigned long cputime_t;
37typedef long icputime_t;
38# define FMT_DATA "l"
39# define CPUTIME_MAX (~0UL)
40#endif
41
42struct stats_cpu {
43 cputime_t cpu_user;
44 cputime_t cpu_nice;
45 cputime_t cpu_system;
46 cputime_t cpu_idle;
47 cputime_t cpu_iowait;
48 cputime_t cpu_steal;
49 cputime_t cpu_irq;
50 cputime_t cpu_softirq;
51 cputime_t cpu_guest;
52};
53
54struct stats_dev {
55 char dname[MAX_DEVICE_NAME];
56 unsigned long long rd_sectors;
57 unsigned long long wr_sectors;
58 unsigned long rd_ops;
59 unsigned long wr_ops;
60};
61
62/* List of devices entered on the command line */
63struct device_list {
64 char dname[MAX_DEVICE_NAME];
65};
66
67/* Globals. Sort by size and access frequency. */
68struct globals {
69 smallint show_all;
70 unsigned devlist_i; /* Index to the list of devices */
71 unsigned total_cpus; /* Number of CPUs */
72 unsigned clk_tck; /* Number of clock ticks per second */
73 struct device_list *dlist;
74 struct stats_dev *saved_stats_dev;
75 struct tm tmtime;
76};
77#define G (*ptr_to_globals)
78#define INIT_G() do { \
79 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
80} while (0)
81
82/* Must match option string! */
83enum {
84 OPT_c = 1 << 0,
85 OPT_d = 1 << 1,
86 OPT_t = 1 << 2,
87 OPT_z = 1 << 3,
88 OPT_k = 1 << 4,
89 OPT_m = 1 << 5,
90};
91
92static ALWAYS_INLINE unsigned get_user_hz(void)
93{
94 return sysconf(_SC_CLK_TCK);
95}
96
97static ALWAYS_INLINE int this_is_smp(void)
98{
99 return (G.total_cpus > 1);
100}
101
102static void print_header(void)
103{
104 char buf[16];
105 struct utsname uts;
106
107 if (uname(&uts) < 0)
108 bb_perror_msg_and_die("uname");
109
110 strftime(buf, sizeof(buf), "%x", &G.tmtime);
111
112 printf("%s %s (%s) \t%s \t_%s_\t(%d CPU)\n\n",
113 uts.sysname, uts.release, uts.nodename,
114 buf, uts.machine, G.total_cpus);
115}
116
Marek Polacek733f26f2010-08-11 17:00:59 +0200117static void get_localtime(struct tm *ptm)
118{
119 time_t timer;
120 time(&timer);
121 localtime_r(&timer, ptm);
122}
123
124static void print_timestamp(void)
125{
126 char buf[20];
127 strftime(buf, sizeof(buf), "%x %X", &G.tmtime);
128 printf("%s\n", buf);
129}
130
Marek Polacek733f26f2010-08-11 17:00:59 +0200131/* Fetch CPU statistics from /proc/stat */
132static void get_cpu_statistics(struct stats_cpu *sc)
133{
134 FILE *fp;
135 char buf[1024];
136
137 fp = xfopen_for_read("/proc/stat");
138
139 memset(sc, 0, sizeof(*sc));
140
141 while (fgets(buf, sizeof(buf), fp)) {
142 /* Does the line starts with "cpu "? */
143 if (starts_with_cpu(buf) && buf[3] == ' ') {
144 sscanf(buf + 4 + 1,
145 "%"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u %"
146 FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u",
147 &sc->cpu_user, &sc->cpu_nice, &sc->cpu_system,
148 &sc->cpu_idle, &sc->cpu_iowait, &sc->cpu_irq,
149 &sc->cpu_softirq, &sc->cpu_steal, &sc->cpu_guest);
150 }
151 }
152
153 fclose(fp);
154}
155
156static cputime_t get_smp_uptime(void)
157{
158 FILE *fp;
159 char buf[sizeof(long)*3 * 2 + 4];
160 unsigned long sec, dec;
161
162 fp = xfopen_for_read("/proc/uptime");
163
164 if (fgets(buf, sizeof(buf), fp))
165 if (sscanf(buf, "%lu.%lu", &sec, &dec) != 2)
166 bb_error_msg_and_die("can't read /proc/uptime");
167
168 fclose(fp);
169
170 return (cputime_t)sec * G.clk_tck + dec * G.clk_tck / 100;
171}
172
173/*
174 * Obtain current uptime in jiffies.
175 * Uptime is sum of individual CPUs' uptimes.
176 */
177static cputime_t get_uptime(const struct stats_cpu *sc)
178{
179 /* NB: Don't include cpu_guest, it is already in cpu_user */
180 return sc->cpu_user + sc->cpu_nice + sc->cpu_system + sc->cpu_idle +
181 + sc->cpu_iowait + sc->cpu_irq + sc->cpu_steal + sc->cpu_softirq;
182}
183
184static ALWAYS_INLINE cputime_t get_interval(cputime_t old, cputime_t new)
185{
186 cputime_t itv = new - old;
187
188 return (itv == 0) ? 1 : itv;
189}
190
191#if CPUTIME_MAX > 0xffffffff
192/*
193 * Handle overflow conditions properly for counters which can have
194 * less bits than cputime_t, depending on the kernel version.
195 */
196/* Surprisingly, on 32bit inlining is a size win */
197static ALWAYS_INLINE cputime_t overflow_safe_sub(cputime_t prev, cputime_t curr)
198{
199 cputime_t v = curr - prev;
200
201 if ((icputime_t)v < 0 /* curr < prev - counter overflow? */
202 && prev <= 0xffffffff /* kernel uses 32bit value for the counter? */
203 ) {
204 /* Add 33th bit set to 1 to curr, compensating for the overflow */
205 /* double shift defeats "warning: left shift count >= width of type" */
206 v += ((cputime_t)1 << 16) << 16;
207 }
208 return v;
209}
210#else
211static ALWAYS_INLINE cputime_t overflow_safe_sub(cputime_t prev, cputime_t curr)
212{
213 return curr - prev;
214}
215#endif
216
217static double percent_value(cputime_t prev, cputime_t curr, cputime_t itv)
218{
219 return ((double)overflow_safe_sub(prev, curr)) / itv * 100;
220}
221
222static void print_stats_cpu_struct(const struct stats_cpu *p,
223 const struct stats_cpu *c, cputime_t itv)
224{
225 printf(" %6.2f %6.2f %6.2f %6.2f %6.2f %6.2f\n",
226 percent_value(p->cpu_user , c->cpu_user , itv),
227 percent_value(p->cpu_nice , c->cpu_nice , itv),
228 percent_value(p->cpu_system + p->cpu_softirq + p->cpu_irq,
229 c->cpu_system + c->cpu_softirq + c->cpu_irq, itv),
230 percent_value(p->cpu_iowait , c->cpu_iowait , itv),
231 percent_value(p->cpu_steal , c->cpu_steal , itv),
232 percent_value(p->cpu_idle , c->cpu_idle , itv)
233 );
234}
235
236static void print_stats_dev_struct(const struct stats_dev *p,
237 const struct stats_dev *c, cputime_t itv)
238{
239 int unit = 1;
240
241 if (option_mask32 & OPT_k)
242 unit = 2;
243 else if (option_mask32 & OPT_m)
244 unit = 2048;
245
246 if (option_mask32 & OPT_z)
247 if (p->rd_ops == c->rd_ops && p->wr_ops == c->wr_ops)
248 return;
249
250 printf("%-13s", c->dname);
251 printf(" %8.2f %12.2f %12.2f %10llu %10llu \n",
252 percent_value(p->rd_ops + p->wr_ops ,
253 /**/ c->rd_ops + c->wr_ops , itv),
254 percent_value(p->rd_sectors, c->rd_sectors, itv) / unit,
255 percent_value(p->wr_sectors, c->wr_sectors, itv) / unit,
256 (c->rd_sectors - p->rd_sectors) / unit,
257 (c->wr_sectors - p->wr_sectors) / unit);
258}
259
260static void cpu_report(const struct stats_cpu *last,
261 const struct stats_cpu *cur,
262 cputime_t itv)
263{
264 /* Always print a header */
265 puts("avg-cpu: %user %nice %system %iowait %steal %idle");
266
267 /* Print current statistics */
268 print_stats_cpu_struct(last, cur, itv);
269}
270
271static void print_devstat_header(void)
272{
273 printf("Device: tps");
274
275 if (option_mask32 & OPT_m)
276 puts(" MB_read/s MB_wrtn/s MB_read MB_wrtn");
277 else if (option_mask32 & OPT_k)
278 puts(" kB_read/s kB_wrtn/s kB_read kB_wrtn");
279 else
280 puts(" Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn");
281}
282
283/*
284 * Is input partition of format [sdaN]?
285 */
286static int is_partition(const char *dev)
287{
288 /* Ok, this is naive... */
289 return ((dev[0] - 's') | (dev[1] - 'd') | (dev[2] - 'a')) == 0 && isdigit(dev[3]);
290}
291
292/*
293 * Return number of numbers on cmdline.
294 * Reasonable values are only 0 (no interval/count specified),
295 * 1 (interval specified) and 2 (both interval and count specified)
296 */
297static int numbers_on_cmdline(int argc, char *argv[])
298{
299 int sum = 0;
300
301 if (isdigit(argv[argc-1][0]))
302 sum++;
303 if (argc > 2 && isdigit(argv[argc-2][0]))
304 sum++;
305
306 return sum;
307}
308
309static int is_dev_in_dlist(const char *dev)
310{
311 int i;
312
313 /* Go through the device list */
314 for (i = 0; i < G.devlist_i; i++)
315 if (strcmp(G.dlist[i].dname, dev) == 0)
316 /* Found a match */
317 return 1;
318
319 /* No match found */
320 return 0;
321}
322
323static void do_disk_statistics(cputime_t itv)
324{
325 FILE *fp;
326 int rc;
327 int i = 0;
328 char buf[128];
329 unsigned major, minor;
Denys Vlasenkofb132e42010-10-29 11:46:52 +0200330 unsigned long wr_ops, dummy; /* %*lu for suppress the conversion wouldn't work */
Marek Polacek733f26f2010-08-11 17:00:59 +0200331 unsigned long long rd_sec_or_wr_ops;
332 unsigned long long rd_sec_or_dummy, wr_sec_or_dummy, wr_sec;
333 struct stats_dev sd;
334
335 fp = xfopen_for_read("/proc/diskstats");
336
337 /* Read and possibly print stats from /proc/diskstats */
338 while (fgets(buf, sizeof(buf), fp)) {
339 rc = sscanf(buf, "%u %u %s %lu %llu %llu %llu %lu %lu %llu %lu %lu %lu %lu",
340 &major, &minor, sd.dname, &sd.rd_ops,
341 &rd_sec_or_dummy, &rd_sec_or_wr_ops, &wr_sec_or_dummy,
342 &wr_ops, &dummy, &wr_sec, &dummy, &dummy, &dummy, &dummy);
343
344 switch (rc) {
345 case 14:
346 sd.wr_ops = wr_ops;
347 sd.rd_sectors = rd_sec_or_wr_ops;
348 sd.wr_sectors = wr_sec;
349 break;
350 case 7:
351 sd.rd_sectors = rd_sec_or_dummy;
352 sd.wr_ops = (unsigned long)rd_sec_or_wr_ops;
353 sd.wr_sectors = wr_sec_or_dummy;
354 break;
355 default:
356 break;
357 }
358
359 if (!G.devlist_i && !is_partition(sd.dname)) {
360 /* User didn't specify device */
361 if (!G.show_all && !sd.rd_ops && !sd.wr_ops) {
362 /* Don't print unused device */
363 continue;
364 }
365 print_stats_dev_struct(&G.saved_stats_dev[i], &sd, itv);
366 G.saved_stats_dev[i] = sd;
367 i++;
368 } else {
369 /* Is device in device list? */
370 if (is_dev_in_dlist(sd.dname)) {
371 /* Print current statistics */
372 print_stats_dev_struct(&G.saved_stats_dev[i], &sd, itv);
373 G.saved_stats_dev[i] = sd;
374 i++;
375 } else
376 continue;
377 }
378 }
Denys Vlasenkodcaed972010-08-12 15:36:34 +0200379
380 fclose(fp);
Marek Polacek733f26f2010-08-11 17:00:59 +0200381}
382
383static void dev_report(cputime_t itv)
384{
385 /* Always print a header */
386 print_devstat_header();
387
388 /* Fetch current disk statistics */
389 do_disk_statistics(itv);
390}
391
392static void save_to_devlist(const char *dname)
393{
394 int i;
395 struct device_list *tmp = G.dlist;
396
397 if (strncmp(dname, "/dev/", 5) == 0)
398 /* We'll ignore prefix '/dev/' */
399 dname += 5;
400
401 /* Go through the list */
402 for (i = 0; i < G.devlist_i; i++, tmp++)
403 if (strcmp(tmp->dname, dname) == 0)
404 /* Already in the list */
405 return;
406
407 /* Add device name to the list */
408 strncpy(tmp->dname, dname, MAX_DEVICE_NAME - 1);
409
410 /* Update device list index */
411 G.devlist_i++;
412}
413
414static unsigned get_number_of_devices(void)
415{
416 FILE *fp;
417 char buf[128];
418 int rv;
419 unsigned n = 0;
420 unsigned long rd_ops, wr_ops;
421 char dname[MAX_DEVICE_NAME];
422
423 fp = xfopen_for_read("/proc/diskstats");
424
425 while (fgets(buf, sizeof(buf), fp)) {
426 rv = sscanf(buf, "%*d %*d %s %lu %*u %*u %*u %lu",
427 dname, &rd_ops, &wr_ops);
428 if (rv == 2 || is_partition(dname))
429 /* A partition */
430 continue;
431 if (!rd_ops && !wr_ops) {
432 /* Unused device */
433 if (!G.show_all)
434 continue;
435 }
436 n++;
437 }
438
439 fclose(fp);
440 return n;
441}
442
443static int number_of_ALL_on_cmdline(char **argv)
444{
445 int alls = 0;
446
447 /* Iterate over cmd line arguments, count "ALL" */
448 while (*argv)
449 if (strcmp(*argv++, "ALL") == 0)
450 alls++;
451
452 return alls;
453}
454
455//usage:#define iostat_trivial_usage
456//usage: "[-c] [-d] [-t] [-z] [-k|-m] [ALL|BLOCKDEV...] [INTERVAL [COUNT]]"
457//usage:#define iostat_full_usage "\n\n"
458//usage: "Report CPU and I/O statistics\n"
459//usage: "\nOptions:"
460//usage: "\n -c Show CPU utilization"
461//usage: "\n -d Show device utilization"
462//usage: "\n -t Print current time"
463//usage: "\n -z Omit devices with no activity"
464//usage: "\n -k Use kb/s"
465//usage: "\n -m Use Mb/s"
466
467int iostat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
468int iostat_main(int argc, char **argv)
469{
470 int opt, dev_num;
471 unsigned interval = 0;
Denys Vlasenkodcaed972010-08-12 15:36:34 +0200472 int count;
Marek Polacek733f26f2010-08-11 17:00:59 +0200473 cputime_t global_uptime[2] = { 0 };
474 cputime_t smp_uptime[2] = { 0 };
475 cputime_t itv;
476 struct stats_cpu stats_cur, stats_last;
477
478 INIT_G();
479
480 memset(&stats_last, 0, sizeof(stats_last));
481
482 /* Get number of clock ticks per sec */
483 G.clk_tck = get_user_hz();
484
485 /* Determine number of CPUs */
Denys Vlasenkoc9b97502010-08-16 02:49:21 +0200486 G.total_cpus = get_cpu_count();
487 if (G.total_cpus == 0)
488 G.total_cpus = 1;
Marek Polacek733f26f2010-08-11 17:00:59 +0200489
490 /* Parse and process arguments */
491 /* -k and -m are mutually exclusive */
492 opt_complementary = "k--m:m--k";
493 opt = getopt32(argv, "cdtzkm");
494 if (!(opt & (OPT_c + OPT_d)))
495 /* Default is -cd */
496 opt |= OPT_c + OPT_d;
497
498 argv += optind;
499 argc -= optind;
500
501 dev_num = argc - numbers_on_cmdline(argc, argv);
502 /* We don't want to allocate space for 'ALL' */
503 dev_num -= number_of_ALL_on_cmdline(argv);
504 if (dev_num > 0)
505 /* Make space for device list */
506 G.dlist = xzalloc(sizeof(G.dlist[0]) * dev_num);
507
508 /* Store device names into device list */
509 while (*argv && !isdigit(*argv[0])) {
510 if (strcmp(*argv, "ALL") != 0)
511 /* If not ALL, save device name */
512 save_to_devlist(*argv);
513 else
514 G.show_all = 1;
515 argv++;
516 }
517
Denys Vlasenkodcaed972010-08-12 15:36:34 +0200518 count = 1;
Marek Polacek733f26f2010-08-11 17:00:59 +0200519 if (*argv) {
520 /* Get interval */
Denys Vlasenko77832482010-08-12 14:14:45 +0200521 interval = xatoi_positive(*argv);
Denys Vlasenkodcaed972010-08-12 15:36:34 +0200522 count = (interval != 0 ? -1 : 1);
Marek Polacek733f26f2010-08-11 17:00:59 +0200523 argv++;
524 if (*argv)
525 /* Get count value */
Denys Vlasenko77832482010-08-12 14:14:45 +0200526 count = xatoi_positive(*argv);
Marek Polacek733f26f2010-08-11 17:00:59 +0200527 }
528
529 /* Allocate space for device stats */
530 if (opt & OPT_d) {
531 G.saved_stats_dev = xzalloc(sizeof(G.saved_stats_dev[0]) *
532 (dev_num ? dev_num : get_number_of_devices())
533 );
534 }
535
536 /* Display header */
537 print_header();
538
539 /* Main loop */
540 for (;;) {
541 /* Fill the time structure */
542 get_localtime(&G.tmtime);
543
544 /* Fetch current CPU statistics */
545 get_cpu_statistics(&stats_cur);
546
547 /* Fetch current uptime */
548 global_uptime[CURRENT] = get_uptime(&stats_cur);
549
550 /* Get interval */
551 itv = get_interval(global_uptime[LAST], global_uptime[CURRENT]);
552
553 if (opt & OPT_t)
554 print_timestamp();
555
556 if (opt & OPT_c) {
557 cpu_report(&stats_last, &stats_cur, itv);
558 if (opt & OPT_d)
559 /* Separate outputs by a newline */
560 bb_putchar('\n');
561 }
562
563 if (opt & OPT_d) {
564 if (this_is_smp()) {
565 smp_uptime[CURRENT] = get_smp_uptime();
566 itv = get_interval(smp_uptime[LAST], smp_uptime[CURRENT]);
567 smp_uptime[LAST] = smp_uptime[CURRENT];
568 }
569 dev_report(itv);
570 }
571
572 if (count > 0) {
573 if (--count == 0)
574 break;
575 }
576
577 /* Backup current stats */
578 global_uptime[LAST] = global_uptime[CURRENT];
579 stats_last = stats_cur;
580
581 bb_putchar('\n');
582 sleep(interval);
583 }
584
585 bb_putchar('\n');
586
587 if (ENABLE_FEATURE_CLEAN_UP) {
588 free(&G);
589 free(G.dlist);
590 free(G.saved_stats_dev);
591 }
592
593 return EXIT_SUCCESS;
594}