1 /* vi: set sw=4 ts=4: */
3 * Report CPU and I/O stats, based on sysstat version 9.1.2 by Sebastien Godard
5 * Copyright (C) 2010 Marek Polacek <mmpolacek@gmail.com>
7 * Licensed under GPLv2, see file LICENSE in this source tree.
10 //config:config IOSTAT
11 //config: bool "iostat"
14 //config: Report CPU and I/O statistics
16 //applet:IF_IOSTAT(APPLET(iostat, BB_DIR_BIN, BB_SUID_DROP))
18 //kbuild:lib-$(CONFIG_IOSTAT) += iostat.o
21 #include <sys/utsname.h> /* struct utsname */
23 //#define debug(fmt, ...) fprintf(stderr, fmt, ## __VA_ARGS__)
24 #define debug(fmt, ...) ((void)0)
26 #define MAX_DEVICE_NAME 12
27 #define MAX_DEVICE_NAME_STR "12"
30 typedef unsigned long long cputime_t;
31 typedef long long icputime_t;
32 # define FMT_DATA "ll"
33 # define CPUTIME_MAX (~0ULL)
35 typedef unsigned long cputime_t;
36 typedef long icputime_t;
38 # define CPUTIME_MAX (~0UL)
59 cputime_t vector[N_STATS_CPU];
69 unsigned long long rd_sectors;
70 unsigned long long wr_sectors;
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;
82 /* Globals. Sort by size and access frequency. */
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;
95 #define G (*ptr_to_globals)
96 #define INIT_G() do { \
97 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
102 /* Must match option string! */
112 static ALWAYS_INLINE int this_is_smp(void)
114 return (G.total_cpus > 1);
117 static void print_header(void)
122 uname(&uts); /* never fails */
124 /* Date representation for the current locale */
125 strftime(buf, sizeof(buf), "%x", &G.tmtime);
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);
132 static void get_localtime(struct tm *ptm)
136 localtime_r(&timer, ptm);
139 static void print_timestamp(void)
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);
148 static cputime_t get_smp_uptime(void)
151 unsigned long sec, dec;
153 fp = xfopen_for_read("/proc/uptime");
155 if (fscanf(fp, "%lu.%lu", &sec, &dec) != 2)
156 bb_error_msg_and_die("can't read '%s'", "/proc/uptime");
160 return (cputime_t)sec * G.clk_tck + dec * G.clk_tck / 100;
163 /* Fetch CPU statistics from /proc/stat */
164 static void get_cpu_statistics(stats_cpu_t *sc)
169 fp = xfopen_for_read("/proc/stat");
171 memset(sc, 0, sizeof(*sc));
173 while (fgets(buf, sizeof(buf), fp)) {
177 /* Does the line start with "cpu "? */
178 if (!starts_with_cpu(buf) || buf[3] != ' ') {
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];
188 ibuf = skip_non_whitespace(ibuf);
194 sc->vector[SMP_UPTIME] = get_smp_uptime();
200 static ALWAYS_INLINE cputime_t get_interval(cputime_t old, cputime_t new)
202 cputime_t itv = new - old;
204 return (itv == 0) ? 1 : itv;
207 #if CPUTIME_MAX > 0xffffffff
209 * Handle overflow conditions properly for counters which can have
210 * less bits than cputime_t, depending on the kernel version.
212 /* Surprisingly, on 32bit inlining is a size win */
213 static ALWAYS_INLINE cputime_t overflow_safe_sub(cputime_t prev, cputime_t curr)
215 cputime_t v = curr - prev;
217 if ((icputime_t)v < 0 /* curr < prev - counter overflow? */
218 && prev <= 0xffffffff /* kernel uses 32bit value for the counter? */
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;
227 static ALWAYS_INLINE cputime_t overflow_safe_sub(cputime_t prev, cputime_t curr)
233 static double percent_value(cputime_t prev, cputime_t curr, cputime_t itv)
235 return ((double)overflow_safe_sub(prev, curr)) / itv * 100;
238 static void print_stats_cpu_struct(stats_cpu_pair_t *stats)
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)
253 static void cpu_report(stats_cpu_pair_t *stats)
255 /* Always print a header */
256 puts("avg-cpu: %user %nice %system %iowait %steal %idle");
258 /* Print current statistics */
259 print_stats_cpu_struct(stats);
262 static void print_stats_dev_struct(stats_dev_t *stats_dev, cputime_t itv)
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)
270 printf("%-13s %8.2f %12.2f %12.2f %10llu %10llu\n",
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
280 static void print_devstat_header(void)
282 printf("Device:%15s%6s%s/s%6s%s/s%6s%s%6s%s\n",
284 G.unit.str, "_read", G.unit.str, "_wrtn",
285 G.unit.str, "_read", G.unit.str, "_wrtn"
290 * Is input partition of format [sdaN]?
292 static int is_partition(const char *dev)
294 /* Ok, this is naive... */
295 return ((dev[0] - 's') | (dev[1] - 'd') | (dev[2] - 'a')) == 0 && isdigit(dev[3]);
298 static stats_dev_t *stats_dev_find_or_new(const char *dev_name)
300 stats_dev_t **curr = &G.stats_dev_list;
302 while (*curr != NULL) {
303 if (strcmp((*curr)->dname, dev_name) == 0)
305 curr = &(*curr)->next;
308 *curr = xzalloc(sizeof(stats_dev_t));
309 strncpy((*curr)->dname, dev_name, MAX_DEVICE_NAME);
313 static void stats_dev_free(stats_dev_t *stats_dev)
316 stats_dev_free(stats_dev->next);
321 static void do_disk_statistics(cputime_t itv)
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;
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))
340 } else if (is_partition(dev_name)) {
344 stats_dev = stats_dev_find_or_new(dev_name);
345 curr_data = &stats_dev->curr_data;
347 rc = sscanf(buf, "%*s %*s %*s %lu %llu %llu %llu %lu %*s %llu",
350 &curr_data->rd_sectors,
353 &curr_data->wr_sectors);
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;
361 if (!G.dev_name_list /* User didn't specify device */
363 && curr_data->rd_ops == 0
364 && curr_data->wr_ops == 0
366 /* Don't print unused device */
370 /* Print current statistics */
371 print_stats_dev_struct(stats_dev, itv);
372 stats_dev->prev_data = *curr_data;
378 static void dev_report(cputime_t itv)
380 /* Always print a header */
381 print_devstat_header();
383 /* Fetch current disk statistics */
384 do_disk_statistics(itv);
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"
398 int iostat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
399 int iostat_main(int argc UNUSED_PARAM, char **argv)
404 stats_cpu_t stats_data[2];
405 smallint current_stats;
409 memset(&stats_data, 0, sizeof(stats_data));
411 /* Get number of clock ticks per sec */
412 G.clk_tck = bb_clk_tck();
414 /* Determine number of CPUs */
415 G.total_cpus = get_cpu_count();
416 if (G.total_cpus == 0)
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)))
425 opt |= OPT_c + OPT_d;
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);
447 interval = xatoi_positive(*argv);
448 count = (interval != 0 ? -1 : 1);
451 /* Get count value */
452 count = xatoi_positive(*argv);
465 get_localtime(&G.tmtime);
473 stats_cpu_pair_t stats;
475 stats.prev = &stats_data[current_stats ^ 1];
476 stats.curr = &stats_data[current_stats];
478 /* Fill the time structure */
479 get_localtime(&G.tmtime);
481 /* Fetch current CPU statistics */
482 get_cpu_statistics(stats.curr);
485 stats.itv = get_interval(
486 stats.prev->vector[GLOBAL_UPTIME],
487 stats.curr->vector[GLOBAL_UPTIME]
496 /* Separate outputs by a newline */
502 stats.itv = get_interval(
503 stats.prev->vector[SMP_UPTIME],
504 stats.curr->vector[SMP_UPTIME]
507 dev_report(stats.itv);
523 if (ENABLE_FEATURE_CLEAN_UP) {
524 llist_free(G.dev_name_list, NULL);
525 stats_dev_free(G.stats_dev_list);