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>
38 //#define CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE /* + 2k */
40 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
44 #include <netinet/in.h> /* htons */
48 typedef int (*cmp_t)(procps_status_t *P, procps_status_t *Q);
50 static procps_status_t *top; /* Hehe */
53 #ifdef CONFIG_FEATURE_USE_TERMIOS
54 static int pid_sort (procps_status_t *P, procps_status_t *Q)
56 return (Q->pid - P->pid);
60 static int mem_sort (procps_status_t *P, procps_status_t *Q)
62 return (int)(Q->rss - P->rss);
65 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
68 static cmp_t sort_function[sort_depth];
70 static int pcpu_sort (procps_status_t *P, procps_status_t *Q)
72 return (Q->pcpu - P->pcpu);
75 static int time_sort (procps_status_t *P, procps_status_t *Q)
77 return (int)((Q->stime + Q->utime) - (P->stime + P->utime));
80 static int mult_lvl_cmp(void* a, void* b) {
83 for(i = 0; i < sort_depth; i++) {
84 cmp_val = (*sort_function[i])(a, b);
91 /* This structure stores some critical information from one frame to
92 the next. mostly used for sorting. Added cumulative and resident fields. */
101 * Calculates percent cpu usage for each task.
104 static struct save_hist *save_history;
106 static unsigned long Hertz;
108 /***********************************************************************
109 * Some values in /proc are expressed in units of 1/HZ seconds, where HZ
110 * is the kernel clock tick rate. One of these units is called a jiffy.
111 * The HZ value used in the kernel may vary according to hacker desire.
112 * According to Linus Torvalds, this is not true. He considers the values
113 * in /proc as being in architecture-dependent units that have no relation
114 * to the kernel clock tick rate. Examination of the kernel source code
115 * reveals that opinion as wishful thinking.
117 * In any case, we need the HZ constant as used in /proc. (the real HZ value
118 * may differ, but we don't care) There are several ways we could get HZ:
120 * 1. Include the kernel header file. If it changes, recompile this library.
121 * 2. Use the sysconf() function. When HZ changes, recompile the C library!
122 * 3. Ask the kernel. This is obviously correct...
124 * Linus Torvalds won't let us ask the kernel, because he thinks we should
125 * not know the HZ value. Oh well, we don't have to listen to him.
126 * Someone smuggled out the HZ value. :-)
128 * This code should work fine, even if Linus fixes the kernel to match his
129 * stated behavior. The code only fails in case of a partial conversion.
133 #define FILE_TO_BUF(filename, fd) do{ \
134 if (fd == -1 && (fd = open(filename, O_RDONLY)) == -1) { \
135 bb_perror_msg_and_die("/proc not be mounted?"); \
137 lseek(fd, 0L, SEEK_SET); \
138 if ((local_n = read(fd, buf, sizeof buf - 1)) < 0) { \
139 bb_perror_msg_and_die("%s", filename); \
141 buf[local_n] = '\0'; \
144 #define FILE_TO_BUF2(filename, fd) do{ \
145 lseek(fd, 0L, SEEK_SET); \
146 if ((local_n = read(fd, buf, sizeof buf - 1)) < 0) { \
147 bb_perror_msg_and_die("%s", filename); \
149 buf[local_n] = '\0'; \
152 static void init_Hertz_value(void) {
153 unsigned long user_j, nice_j, sys_j, other_j; /* jiffies (clock ticks) */
154 double up_1, up_2, seconds;
155 unsigned long jiffies, h;
160 long smp_num_cpus = sysconf(_SC_NPROCESSORS_CONF);
162 if(smp_num_cpus<1) smp_num_cpus=1;
166 FILE_TO_BUF("uptime", uptime_fd);
167 up_1 = strtod(buf, 0);
168 FILE_TO_BUF("stat", stat_fd);
169 sscanf(buf, "cpu %lu %lu %lu %lu", &user_j, &nice_j, &sys_j, &other_j);
170 FILE_TO_BUF2("uptime", uptime_fd);
171 up_2 = strtod(buf, 0);
172 } while((long)( (up_2-up_1)*1000.0/up_1 )); /* want under 0.1% error */
177 jiffies = user_j + nice_j + sys_j + other_j;
178 seconds = (up_1 + up_2) / 2;
179 h = (unsigned long)( (double)jiffies/seconds/smp_num_cpus );
180 /* actual values used by 2.4 kernels: 32 64 100 128 1000 1024 1200 */
182 case 30 ... 34 : Hertz = 32; break; /* ia64 emulator */
183 case 48 ... 52 : Hertz = 50; break;
184 case 58 ... 62 : Hertz = 60; break;
185 case 63 ... 65 : Hertz = 64; break; /* StrongARM /Shark */
186 case 95 ... 105 : Hertz = 100; break; /* normal Linux */
187 case 124 ... 132 : Hertz = 128; break; /* MIPS, ARM */
188 case 195 ... 204 : Hertz = 200; break; /* normal << 1 */
189 case 253 ... 260 : Hertz = 256; break;
190 case 295 ... 304 : Hertz = 300; break; /* 3 cpus */
191 case 393 ... 408 : Hertz = 400; break; /* normal << 2 */
192 case 495 ... 504 : Hertz = 500; break; /* 5 cpus */
193 case 595 ... 604 : Hertz = 600; break; /* 6 cpus */
194 case 695 ... 704 : Hertz = 700; break; /* 7 cpus */
195 case 790 ... 808 : Hertz = 800; break; /* normal << 3 */
196 case 895 ... 904 : Hertz = 900; break; /* 9 cpus */
197 case 990 ... 1010 : Hertz = 1000; break; /* ARM */
198 case 1015 ... 1035 : Hertz = 1024; break; /* Alpha, ia64 */
199 case 1095 ... 1104 : Hertz = 1100; break; /* 11 cpus */
200 case 1180 ... 1220 : Hertz = 1200; break; /* Alpha */
202 /* If 32-bit or big-endian (not Alpha or ia64), assume HZ is 100. */
203 Hertz = (sizeof(long)==sizeof(int) || htons(999)==999) ? 100UL : 1024UL;
207 static void do_stats(void)
210 static struct timeval oldtime;
211 struct timezone timez;
214 procps_status_t *cur;
215 int total_time, i, n;
216 static int prev_count;
217 int systime, usrtime, pid;
219 struct save_hist *New_save_hist;
222 * Finds the current time (in microseconds) and calculates the time
223 * elapsed since the last update.
225 gettimeofday(&t, &timez);
226 elapsed_time = (t.tv_sec - oldtime.tv_sec)
227 + (float) (t.tv_usec - oldtime.tv_usec) / 1000000.0;
228 oldtime.tv_sec = t.tv_sec;
229 oldtime.tv_usec = t.tv_usec;
231 New_save_hist = alloca(sizeof(struct save_hist)*ntop);
233 * Make a pass through the data to get stats.
235 for(n = 0; n < ntop; n++) {
239 * Calculate time in cur process. Time is sum of user time
240 * (usrtime) plus system time (systime).
242 systime = cur->stime;
243 usrtime = cur->utime;
245 total_time = systime + usrtime;
246 New_save_hist[n].ticks = total_time;
247 New_save_hist[n].pid = pid;
248 New_save_hist[n].stime = systime;
249 New_save_hist[n].utime = usrtime;
251 /* find matching entry from previous pass */
252 for (i = 0; i < prev_count; i++) {
253 if (save_history[i].pid == pid) {
254 total_time -= save_history[i].ticks;
255 systime -= save_history[i].stime;
256 usrtime -= save_history[i].utime;
262 * Calculate percent cpu time for cur task.
264 i = (total_time * 10 * 100/Hertz) / elapsed_time;
272 * Save cur frame's information.
275 save_history = memcpy(xmalloc(sizeof(struct save_hist)*n), New_save_hist,
276 sizeof(struct save_hist)*n);
278 qsort(top, n, sizeof(procps_status_t), (void*)mult_lvl_cmp);
281 static cmp_t sort_function;
282 #endif /* CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE */
284 /* display generic info (meminfo / loadavg) */
285 static unsigned long display_generic(void)
289 float avg1, avg2, avg3;
290 unsigned long total, used, mfree, shared, buffers, cached;
291 unsigned int needs_conversion = 1;
293 /* read memory info */
294 fp = bb_xfopen("meminfo", "r");
297 * Old kernels (such as 2.4.x) had a nice summary of memory info that
298 * we could parse, however this is gone entirely in 2.6. Try parsing
299 * the old way first, and if that fails, parse each field manually.
301 * First, we read in the first line. Old kernels will have bogus
302 * strings we don't care about, whereas new kernels will start right
306 if (fscanf(fp, "MemTotal: %lu %s\n", &total, buf) != 2) {
307 fgets(buf, sizeof(buf), fp); /* skip first line */
309 fscanf(fp, "Mem: %lu %lu %lu %lu %lu %lu",
310 &total, &used, &mfree, &shared, &buffers, &cached);
313 * Revert to manual parsing, which incidentally already has the
314 * sizes in kilobytes. This should be safe for both 2.4 and
317 needs_conversion = 0;
319 fscanf(fp, "MemFree: %lu %s\n", &mfree, buf);
322 * MemShared: is no longer present in 2.6. Report this as 0,
323 * to maintain consistent behavior with normal procps.
325 if (fscanf(fp, "MemShared: %lu %s\n", &shared, buf) != 2)
328 fscanf(fp, "Buffers: %lu %s\n", &buffers, buf);
329 fscanf(fp, "Cached: %lu %s\n", &cached, buf);
331 used = total - mfree;
335 /* read load average */
336 fp = bb_xfopen("loadavg", "r");
337 if (fscanf(fp, "%f %f %f", &avg1, &avg2, &avg3) != 3) {
338 bb_error_msg_and_die("failed to read '%s'", "loadavg");
342 if (needs_conversion) {
343 /* convert to kilobytes */
352 /* output memory info and load average */
353 /* clear screen & go to top */
354 printf("\e[H\e[J" "Mem: "
355 "%ldK used, %ldK free, %ldK shrd, %ldK buff, %ldK cached\n",
356 used, mfree, shared, buffers, cached);
357 printf("Load average: %.2f, %.2f, %.2f "
358 "(State: S=sleeping R=running, W=waiting)\n",
364 /* display process statuses */
365 static void display_status(int count, int col)
367 procps_status_t *s = top;
369 unsigned long total_memory = display_generic();
371 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
372 /* what info of the processes is shown */
373 printf("\n\e[7m PID USER STATUS RSS PPID %%CPU %%MEM COMMAND\e[0m\n");
375 printf("\n\e[7m PID USER STATUS RSS PPID %%MEM COMMAND\e[0m\n");
379 char *namecmd = s->short_cmd;
382 pmem = 1000.0 * s->rss / total_memory;
383 if (pmem > 999) pmem = 999;
386 sprintf(rss_str_buf, "%6ldM", s->rss/1024);
388 sprintf(rss_str_buf, "%7ld", s->rss);
389 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
390 printf("%5d %-8s %s %s %5d %2d.%d %2u.%u ",
391 s->pid, s->user, s->state, rss_str_buf, s->ppid,
392 s->pcpu/10, s->pcpu%10, pmem/10, pmem%10);
394 printf("%5d %-8s %s %s %5d %2u.%u ",
395 s->pid, s->user, s->state, rss_str_buf, s->ppid,
398 if(strlen(namecmd) > col)
400 printf("%s\n", namecmd);
405 static void clearmems(void)
412 #ifdef CONFIG_FEATURE_USE_TERMIOS
414 #include <sys/time.h>
418 static struct termios initial_settings;
420 static void reset_term(void)
422 tcsetattr(0, TCSANOW, (void *) &initial_settings);
423 #ifdef CONFIG_FEATURE_CLEAN_UP
425 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
428 #endif /* CONFIG_FEATURE_CLEAN_UP */
431 static void sig_catcher (int sig)
435 #endif /* CONFIG_FEATURE_USE_TERMIOS */
438 int top_main(int argc, char **argv)
440 int opt, interval, lines, col;
442 #ifdef CONFIG_FEATURE_USE_TERMIOS
443 struct termios new_settings;
448 #endif /* CONFIG_FEATURE_USE_TERMIOS */
450 /* do normal option parsing */
451 opt = bb_getopt_ulflags(argc, argv, "d:", &sinterval);
453 interval = atoi(sinterval);
455 /* Default update rate is 5 seconds */
459 /* Default to 25 lines - 5 lines for status */
461 /* Default CMD format size */
462 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
467 /* change to /proc */
468 if (chdir("/proc") < 0) {
469 bb_perror_msg_and_die("chdir('/proc')");
471 #ifdef CONFIG_FEATURE_USE_TERMIOS
472 tcgetattr(0, (void *) &initial_settings);
473 memcpy(&new_settings, &initial_settings, sizeof(struct termios));
474 new_settings.c_lflag &= ~(ISIG | ICANON); /* unbuffered input */
475 /* Turn off echoing */
476 new_settings.c_lflag &= ~(ECHO | ECHONL);
478 signal (SIGTERM, sig_catcher);
479 sigaction (SIGTERM, (struct sigaction *) 0, &sa);
480 sa.sa_flags |= SA_RESTART;
481 sa.sa_flags &= ~SA_INTERRUPT;
482 sigaction (SIGTERM, &sa, (struct sigaction *) 0);
483 sigaction (SIGINT, &sa, (struct sigaction *) 0);
484 tcsetattr(0, TCSANOW, (void *) &new_settings);
487 get_terminal_width_height(0, &col, &lines);
490 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
491 col = col - 80 + 35 - 6;
496 #endif /* CONFIG_FEATURE_USE_TERMIOS */
498 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
499 sort_function[0] = pcpu_sort;
500 sort_function[1] = mem_sort;
501 sort_function[2] = time_sort;
503 sort_function = mem_sort;
504 #endif /* CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE */
507 /* read process IDs & status for all the processes */
510 while ((p = procps_scan(0)) != 0) {
513 top = xrealloc(top, (++ntop)*sizeof(procps_status_t));
514 memcpy(top + n, p, sizeof(procps_status_t));
517 bb_perror_msg_and_die("scandir('/proc')");
519 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
529 qsort(top, ntop, sizeof(procps_status_t), (void*)sort_function);
530 #endif /* CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE */
535 /* show status for each of the processes */
536 display_status(opt, col);
537 #ifdef CONFIG_FEATURE_USE_TERMIOS
538 tv.tv_sec = interval;
541 FD_SET (0, &readfds);
542 select (1, &readfds, NULL, NULL, &tv);
543 if (FD_ISSET (0, &readfds)) {
544 if (read (0, &c, 1) <= 0) { /* signal */
547 if(c == 'q' || c == initial_settings.c_cc[VINTR])
550 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
551 sort_function[0] = mem_sort;
552 sort_function[1] = pcpu_sort;
553 sort_function[2] = time_sort;
555 sort_function = mem_sort;
558 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
560 sort_function[0] = pcpu_sort;
561 sort_function[1] = mem_sort;
562 sort_function[2] = time_sort;
565 sort_function[0] = time_sort;
566 sort_function[1] = mem_sort;
567 sort_function[2] = pcpu_sort;
571 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
572 sort_function[0] = pid_sort;
574 sort_function = pid_sort;
580 #endif /* CONFIG_FEATURE_USE_TERMIOS */