2 * A tiny 'top' utility.
4 * This is written specifically for the linux /proc/<PID>/stat(m)
7 * This reads the PIDs of all processes and their status and shows
8 * the status of processes (first ones that fit to screen) at given
12 * - At startup this changes to /proc, all the reads are then
15 * (C) Eero Tamminen <oak at welho dot com>
17 * Rewritten by Vladimir Oleynik (C) 2002 <dzo@simtreas.ru>
20 /* Original code Copyrights */
22 * Copyright (c) 1992 Branko Lankester
23 * Copyright (c) 1992 Roger Binns
24 * Copyright (C) 1994-1996 Charles L. Blake.
25 * Copyright (C) 1992-1998 Michael K. Johnson
26 * May be distributed under the conditions of the
27 * GNU Library General Public License
30 #include <sys/types.h>
35 #include <sys/ioctl.h>
40 //#define FEATURE_CPU_USAGE_PERCENTAGE /* + 2k */
42 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
46 #include <netinet/in.h> /* htons */
50 typedef int (*cmp_t)(procps_status_t *P, procps_status_t *Q);
52 static procps_status_t *top; /* Hehe */
56 static int pid_sort (procps_status_t *P, procps_status_t *Q)
58 return (Q->pid - P->pid);
61 static int mem_sort (procps_status_t *P, procps_status_t *Q)
63 return (int)(Q->rss - P->rss);
66 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
69 static cmp_t sort_function[sort_depth];
71 static int pcpu_sort (procps_status_t *P, procps_status_t *Q)
73 return (Q->pcpu - P->pcpu);
76 static int time_sort (procps_status_t *P, procps_status_t *Q)
78 return (int)((Q->stime + Q->utime) - (P->stime + P->utime));
81 int mult_lvl_cmp(void* a, void* b) {
84 for(i = 0; i < sort_depth; i++) {
85 cmp_val = (*sort_function[i])(a, b);
92 /* This structure stores some critical information from one frame to
93 the next. mostly used for sorting. Added cumulative and resident fields. */
102 * Calculates percent cpu usage for each task.
105 static struct save_hist *save_history;
107 static unsigned long Hertz;
109 /***********************************************************************
110 * Some values in /proc are expressed in units of 1/HZ seconds, where HZ
111 * is the kernel clock tick rate. One of these units is called a jiffy.
112 * The HZ value used in the kernel may vary according to hacker desire.
113 * According to Linus Torvalds, this is not true. He considers the values
114 * in /proc as being in architecture-dependent units that have no relation
115 * to the kernel clock tick rate. Examination of the kernel source code
116 * reveals that opinion as wishful thinking.
118 * In any case, we need the HZ constant as used in /proc. (the real HZ value
119 * may differ, but we don't care) There are several ways we could get HZ:
121 * 1. Include the kernel header file. If it changes, recompile this library.
122 * 2. Use the sysconf() function. When HZ changes, recompile the C library!
123 * 3. Ask the kernel. This is obviously correct...
125 * Linus Torvalds won't let us ask the kernel, because he thinks we should
126 * not know the HZ value. Oh well, we don't have to listen to him.
127 * Someone smuggled out the HZ value. :-)
129 * This code should work fine, even if Linus fixes the kernel to match his
130 * stated behavior. The code only fails in case of a partial conversion.
134 #define FILE_TO_BUF(filename, fd) do{ \
135 if (fd == -1 && (fd = open(filename, O_RDONLY)) == -1) { \
136 bb_perror_msg_and_die("/proc not be mounted?"); \
138 lseek(fd, 0L, SEEK_SET); \
139 if ((local_n = read(fd, buf, sizeof buf - 1)) < 0) { \
140 bb_perror_msg_and_die("%s", filename); \
142 buf[local_n] = '\0'; \
145 #define FILE_TO_BUF2(filename, fd) do{ \
146 lseek(fd, 0L, SEEK_SET); \
147 if ((local_n = read(fd, buf, sizeof buf - 1)) < 0) { \
148 bb_perror_msg_and_die("%s", filename); \
150 buf[local_n] = '\0'; \
153 static void init_Hertz_value(void) {
154 unsigned long user_j, nice_j, sys_j, other_j; /* jiffies (clock ticks) */
155 double up_1, up_2, seconds;
156 unsigned long jiffies, h;
161 long smp_num_cpus = sysconf(_SC_NPROCESSORS_CONF);
163 if(smp_num_cpus<1) smp_num_cpus=1;
167 FILE_TO_BUF("uptime", uptime_fd);
168 up_1 = strtod(buf, 0);
169 FILE_TO_BUF("stat", stat_fd);
170 sscanf(buf, "cpu %lu %lu %lu %lu", &user_j, &nice_j, &sys_j, &other_j);
171 FILE_TO_BUF2("uptime", uptime_fd);
172 up_2 = strtod(buf, 0);
173 } while((long)( (up_2-up_1)*1000.0/up_1 )); /* want under 0.1% error */
178 jiffies = user_j + nice_j + sys_j + other_j;
179 seconds = (up_1 + up_2) / 2;
180 h = (unsigned long)( (double)jiffies/seconds/smp_num_cpus );
181 /* actual values used by 2.4 kernels: 32 64 100 128 1000 1024 1200 */
183 case 30 ... 34 : Hertz = 32; break; /* ia64 emulator */
184 case 48 ... 52 : Hertz = 50; break;
185 case 58 ... 62 : Hertz = 60; break;
186 case 63 ... 65 : Hertz = 64; break; /* StrongARM /Shark */
187 case 95 ... 105 : Hertz = 100; break; /* normal Linux */
188 case 124 ... 132 : Hertz = 128; break; /* MIPS, ARM */
189 case 195 ... 204 : Hertz = 200; break; /* normal << 1 */
190 case 253 ... 260 : Hertz = 256; break;
191 case 295 ... 304 : Hertz = 300; break; /* 3 cpus */
192 case 393 ... 408 : Hertz = 400; break; /* normal << 2 */
193 case 495 ... 504 : Hertz = 500; break; /* 5 cpus */
194 case 595 ... 604 : Hertz = 600; break; /* 6 cpus */
195 case 695 ... 704 : Hertz = 700; break; /* 7 cpus */
196 case 790 ... 808 : Hertz = 800; break; /* normal << 3 */
197 case 895 ... 904 : Hertz = 900; break; /* 9 cpus */
198 case 990 ... 1010 : Hertz = 1000; break; /* ARM */
199 case 1015 ... 1035 : Hertz = 1024; break; /* Alpha, ia64 */
200 case 1095 ... 1104 : Hertz = 1100; break; /* 11 cpus */
201 case 1180 ... 1220 : Hertz = 1200; break; /* Alpha */
203 /* If 32-bit or big-endian (not Alpha or ia64), assume HZ is 100. */
204 Hertz = (sizeof(long)==sizeof(int) || htons(999)==999) ? 100UL : 1024UL;
208 static void do_stats(void)
211 static struct timeval oldtime;
212 struct timezone timez;
215 procps_status_t *cur;
216 int total_time, i, n;
217 static int prev_count;
218 int systime, usrtime, pid;
220 struct save_hist *New_save_hist;
223 * Finds the current time (in microseconds) and calculates the time
224 * elapsed since the last update.
226 gettimeofday(&t, &timez);
227 elapsed_time = (t.tv_sec - oldtime.tv_sec)
228 + (float) (t.tv_usec - oldtime.tv_usec) / 1000000.0;
229 oldtime.tv_sec = t.tv_sec;
230 oldtime.tv_usec = t.tv_usec;
232 New_save_hist = alloca(sizeof(struct save_hist)*ntop);
234 * Make a pass through the data to get stats.
236 for(n = 0; n < ntop; n++) {
240 * Calculate time in cur process. Time is sum of user time
241 * (usrtime) plus system time (systime).
243 systime = cur->stime;
244 usrtime = cur->utime;
246 total_time = systime + usrtime;
247 New_save_hist[n].ticks = total_time;
248 New_save_hist[n].pid = pid;
249 New_save_hist[n].stime = systime;
250 New_save_hist[n].utime = usrtime;
252 /* find matching entry from previous pass */
253 for (i = 0; i < prev_count; i++) {
254 if (save_history[i].pid == pid) {
255 total_time -= save_history[i].ticks;
256 systime -= save_history[i].stime;
257 usrtime -= save_history[i].utime;
263 * Calculate percent cpu time for cur task.
265 i = (total_time * 10 * 100/Hertz) / elapsed_time;
273 * Save cur frame's information.
276 save_history = memcpy(xmalloc(sizeof(struct save_hist)*n), New_save_hist,
277 sizeof(struct save_hist)*n);
279 qsort(top, n, sizeof(procps_status_t), (void*)mult_lvl_cmp);
282 static cmp_t sort_function;
283 #endif /* FEATURE_CPU_USAGE_PERCENTAGE */
285 /* display generic info (meminfo / loadavg) */
286 static unsigned long display_generic(void)
290 float avg1, avg2, avg3;
291 unsigned long total, used, mfree, shared, buffers, cached;
292 unsigned int needs_conversion = 1;
294 /* read memory info */
295 fp = bb_xfopen("meminfo", "r");
298 * Old kernels (such as 2.4.x) had a nice summary of memory info that
299 * we could parse, however this is gone entirely in 2.6. Try parsing
300 * the old way first, and if that fails, parse each field manually.
302 * First, we read in the first line. Old kernels will have bogus
303 * strings we don't care about, whereas new kernels will start right
307 if (fscanf(fp, "MemTotal: %lu %s\n", &total, buf) != 2) {
308 fgets(buf, sizeof(buf), fp); /* skip first line */
310 fscanf(fp, "Mem: %lu %lu %lu %lu %lu %lu",
311 &total, &used, &mfree, &shared, &buffers, &cached);
314 * Revert to manual parsing, which incidentally already has the
315 * sizes in kilobytes. This should be safe for both 2.4 and
318 needs_conversion = 0;
320 fscanf(fp, "MemFree: %lu %s\n", &mfree, buf);
323 * MemShared: is no longer present in 2.6. Report this as 0,
324 * to maintain consistent behavior with normal procps.
326 if (fscanf(fp, "MemShared: %lu %s\n", &shared, buf) != 2)
329 fscanf(fp, "Buffers: %lu %s\n", &buffers, buf);
330 fscanf(fp, "Cached: %lu %s\n", &cached, buf);
332 used = total - mfree;
336 /* read load average */
337 fp = bb_xfopen("loadavg", "r");
338 if (fscanf(fp, "%f %f %f", &avg1, &avg2, &avg3) != 3) {
339 bb_error_msg_and_die("failed to read '%s'", "loadavg");
343 if (needs_conversion) {
344 /* convert to kilobytes */
353 /* output memory info and load average */
354 /* clear screen & go to top */
355 printf("\e[H\e[J" "Mem: "
356 "%ldK used, %ldK free, %ldK shrd, %ldK buff, %ldK cached\n",
357 used, mfree, shared, buffers, cached);
358 printf("Load average: %.2f, %.2f, %.2f "
359 "(State: S=sleeping R=running, W=waiting)\n",
365 /* display process statuses */
366 static void display_status(int count, int col)
368 procps_status_t *s = top;
370 unsigned long total_memory = display_generic();
372 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
373 /* what info of the processes is shown */
374 printf("\n\e[7m PID USER STATUS RSS PPID %%CPU %%MEM COMMAND\e[0m\n");
376 printf("\n\e[7m PID USER STATUS RSS PPID %%MEM COMMAND\e[0m\n");
380 char *namecmd = s->short_cmd;
383 pmem = 1000.0 * s->rss / total_memory;
384 if (pmem > 999) pmem = 999;
387 sprintf(rss_str_buf, "%6ldM", s->rss/1024);
389 sprintf(rss_str_buf, "%7ld", s->rss);
390 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
391 printf("%5d %-8s %s %s %5d %2d.%d %2u.%u ",
392 s->pid, s->user, s->state, rss_str_buf, s->ppid,
393 s->pcpu/10, s->pcpu%10, pmem/10, pmem%10);
395 printf("%5d %-8s %s %s %5d %2u.%u ",
396 s->pid, s->user, s->state, rss_str_buf, s->ppid,
399 if(strlen(namecmd) > col)
401 printf("%s\n", namecmd);
406 static void clearmems(void)
413 #if defined CONFIG_FEATURE_USE_TERMIOS
415 #include <sys/time.h>
419 static struct termios initial_settings;
421 static void reset_term(void)
423 tcsetattr(0, TCSANOW, (void *) &initial_settings);
424 #ifdef CONFIG_FEATURE_CLEAN_UP
426 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
429 #endif /* CONFIG_FEATURE_CLEAN_UP */
432 static void sig_catcher (int sig)
436 #endif /* CONFIG_FEATURE_USE_TERMIOS */
439 int top_main(int argc, char **argv)
441 int opt, interval, lines, col;
442 #if defined CONFIG_FEATURE_USE_TERMIOS
443 struct termios new_settings;
448 #endif /* CONFIG_FEATURE_USE_TERMIOS */
450 /* Default update rate is 5 seconds */
453 /* do normal option parsing */
454 while ((opt = getopt(argc, argv, "d:")) > 0) {
457 interval = atoi(optarg);
464 /* Default to 25 lines - 5 lines for status */
466 /* Default CMD format size */
467 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
472 /* change to /proc */
473 if (chdir("/proc") < 0) {
474 bb_perror_msg_and_die("chdir('/proc')");
476 #if defined CONFIG_FEATURE_USE_TERMIOS
477 tcgetattr(0, (void *) &initial_settings);
478 memcpy(&new_settings, &initial_settings, sizeof(struct termios));
479 new_settings.c_lflag &= ~(ISIG | ICANON); /* unbuffered input */
480 /* Turn off echoing */
481 new_settings.c_lflag &= ~(ECHO | ECHONL);
483 signal (SIGTERM, sig_catcher);
484 sigaction (SIGTERM, (struct sigaction *) 0, &sa);
485 sa.sa_flags |= SA_RESTART;
486 sa.sa_flags &= ~SA_INTERRUPT;
487 sigaction (SIGTERM, &sa, (struct sigaction *) 0);
488 sigaction (SIGINT, &sa, (struct sigaction *) 0);
489 tcsetattr(0, TCSANOW, (void *) &new_settings);
492 get_terminal_width_height(0, &col, &lines);
495 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
496 col = col - 80 + 35 - 6;
501 #endif /* CONFIG_FEATURE_USE_TERMIOS */
502 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
503 sort_function[0] = pcpu_sort;
504 sort_function[1] = mem_sort;
505 sort_function[2] = time_sort;
507 sort_function = mem_sort;
510 /* read process IDs & status for all the processes */
513 #ifdef CONFIG_SELINUX
514 while ((p = procps_scan(0, 0, NULL) ) != 0) {
516 while ((p = procps_scan(0)) != 0) {
520 top = xrealloc(top, (++ntop)*sizeof(procps_status_t));
521 memcpy(top + n, p, sizeof(procps_status_t));
524 bb_perror_msg_and_die("scandir('/proc')");
526 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
536 qsort(top, ntop, sizeof(procps_status_t), (void*)sort_function);
542 /* show status for each of the processes */
543 display_status(opt, col);
544 #if defined CONFIG_FEATURE_USE_TERMIOS
545 tv.tv_sec = interval;
548 FD_SET (0, &readfds);
549 select (1, &readfds, NULL, NULL, &tv);
550 if (FD_ISSET (0, &readfds)) {
551 if (read (0, &c, 1) <= 0) { /* signal */
554 if(c == 'q' || c == initial_settings.c_cc[VINTR])
557 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
558 sort_function[0] = mem_sort;
559 sort_function[1] = pcpu_sort;
560 sort_function[2] = time_sort;
562 sort_function = mem_sort;
565 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
567 sort_function[0] = pcpu_sort;
568 sort_function[1] = mem_sort;
569 sort_function[2] = time_sort;
572 sort_function[0] = time_sort;
573 sort_function[1] = mem_sort;
574 sort_function[2] = pcpu_sort;
578 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
579 sort_function[0] = pid_sort;
581 sort_function = pid_sort;
587 #endif /* CONFIG_FEATURE_USE_TERMIOS */