procps/mpstat.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Per-processor statistics, 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 tarball for details.
   8  */
   9
  10 //applet:IF_MPSTAT(APPLET(mpstat, _BB_DIR_BIN, _BB_SUID_DROP))
  11
  12 //kbuild:lib-$(CONFIG_MPSTAT) += mpstat.o
  13
  14 //config:config MPSTAT
  15 //config:       bool "mpstat"
  16 //config:       default y
  17 //config:       help
  18 //config:         Per-processor statistics
  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 /* Size of /proc/interrupts line, CPU data excluded */
  27 #define INTERRUPTS_LINE    64
  28 /* Maximum number of interrupts */
  29 #define NR_IRQS            256
  30 #define NR_IRQCPU_PREALLOC 3
  31 #define MAX_IRQNAME_LEN    16
  32 #define MAX_PF_NAME        512
  33 /* sysstat 9.0.6 uses width 8, but newer code which also prints /proc/softirqs
  34  * data needs more: "interrupts" in /proc/softirqs have longer names,
  35  * most are up to 8 chars, one (BLOCK_IOPOLL) is even longer.
  36  * We are printing headers in the " IRQNAME/s" form, experimentally
  37  * anything smaller than 10 chars looks ugly for /proc/softirqs stats.
  38  */
  39 #define INTRATE_SCRWIDTH   10
  40 #define INTRATE_SCRWIDTH_STR "10"
  41
  42 /* System files */
  43 #define SYSFS_DEVCPU      "/sys/devices/system/cpu"
  44 #define PROCFS_STAT       "/proc/stat"
  45 #define PROCFS_INTERRUPTS "/proc/interrupts"
  46 #define PROCFS_SOFTIRQS   "/proc/softirqs"
  47 #define PROCFS_UPTIME     "/proc/uptime"
  48
  49
  50 #if 1
  51 typedef unsigned long long data_t;
  52 typedef long long idata_t;
  53 #define FMT_DATA "ll"
  54 #define DATA_MAX ULLONG_MAX
  55 #else
  56 typedef unsigned long data_t;
  57 typedef long idata_t;
  58 #define FMT_DATA "l"
  59 #define DATA_MAX ULONG_MAX
  60 #endif
  61
  62
  63 struct stats_irqcpu {
  64         unsigned interrupt;
  65         char irq_name[MAX_IRQNAME_LEN];
  66 };
  67
  68 struct stats_cpu {
  69         data_t cpu_user;
  70         data_t cpu_nice;
  71         data_t cpu_system;
  72         data_t cpu_idle;
  73         data_t cpu_iowait;
  74         data_t cpu_steal;
  75         data_t cpu_irq;
  76         data_t cpu_softirq;
  77         data_t cpu_guest;
  78 };
  79
  80 struct stats_irq {
  81         data_t irq_nr;
  82 };
  83
  84
  85 /* Globals. Sort by size and access frequency. */
  86 struct globals {
  87         int interval;
  88         int count;
  89         unsigned cpu_nr;                /* Number of CPUs */
  90         unsigned irqcpu_nr;             /* Number of interrupts per CPU */
  91         unsigned softirqcpu_nr;         /* Number of soft interrupts per CPU */
  92         unsigned options;
  93         unsigned hz;
  94         unsigned cpu_bitmap_len;
  95         smallint p_option;
  96         smallint header_done;
  97         smallint avg_header_done;
  98         unsigned char *cpu_bitmap;      /* Bit 0: global, bit 1: 1st proc... */
  99         data_t global_uptime[3];
 100         data_t per_cpu_uptime[3];
 101         struct stats_cpu *st_cpu[3];
 102         struct stats_irq *st_irq[3];
 103         struct stats_irqcpu *st_irqcpu[3];
 104         struct stats_irqcpu *st_softirqcpu[3];
 105         struct tm timestamp[3];
 106 };
 107 #define G (*ptr_to_globals)
 108 #define INIT_G() do { \
 109         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 110 } while (0)
 111
 112 /* The selected interrupts statistics (bits in G.options) */
 113 enum {
 114         D_CPU      = 1 << 0,
 115         D_IRQ_SUM  = 1 << 1,
 116         D_IRQ_CPU  = 1 << 2,
 117         D_SOFTIRQS = 1 << 3,
 118 };
 119
 120
 121 /* Does str start with "cpu"? */
 122 static int starts_with_cpu(const char *str)
 123 {
 124         return !((str[0] - 'c') | (str[1] - 'p') | (str[2] - 'u'));
 125 }
 126
 127 /* Is option on? */
 128 static ALWAYS_INLINE int display_opt(int opt)
 129 {
 130         return (opt & G.options);
 131 }
 132
 133 #if DATA_MAX > 0xffffffff
 134 /*
 135  * Handle overflow conditions properly for counters which can have
 136  * less bits than data_t, depending on the kernel version.
 137  */
 138 /* Surprisingly, on 32bit inlining is a size win */
 139 static ALWAYS_INLINE data_t overflow_safe_sub(data_t prev, data_t curr)
 140 {
 141         data_t v = curr - prev;
 142
 143         if ((idata_t)v < 0     /* curr < prev - counter overflow? */
 144          && prev <= 0xffffffff /* kernel uses 32bit value for the counter? */
 145         ) {
 146                 /* Add 33th bit set to 1 to curr, compensating for the overflow */
 147                 /* double shift defeats "warning: left shift count >= width of type" */
 148                 v += ((data_t)1 << 16) << 16;
 149         }
 150         return v;
 151 }
 152 #else
 153 static ALWAYS_INLINE data_t overflow_safe_sub(data_t prev, data_t curr)
 154 {
 155         return curr - prev;
 156 }
 157 #endif
 158
 159 static double percent_value(data_t prev, data_t curr, data_t itv)
 160 {
 161         return ((double)overflow_safe_sub(prev, curr)) / itv * 100;
 162 }
 163
 164 static double hz_value(data_t prev, data_t curr, data_t itv)
 165 {
 166         return ((double)overflow_safe_sub(prev, curr)) / itv * G.hz;
 167 }
 168
 169 static ALWAYS_INLINE data_t jiffies_diff(data_t old, data_t new)
 170 {
 171         data_t diff = new - old;
 172         return (diff == 0) ? 1 : diff;
 173 }
 174
 175 static int is_cpu_in_bitmap(unsigned cpu)
 176 {
 177         return G.cpu_bitmap[cpu >> 3] & (1 << (cpu & 7));
 178 }
 179
 180 static void write_irqcpu_stats(struct stats_irqcpu *per_cpu_stats[],
 181                 int total_irqs,
 182                 data_t itv,
 183                 int prev, int current,
 184                 const char *prev_str, const char *current_str)
 185 {
 186         int j;
 187         int offset, cpu;
 188         struct stats_irqcpu *p0, *q0;
 189
 190         /* Check if number of IRQs has changed */
 191         if (G.interval != 0) {
 192                 for (j = 0; j <= total_irqs; j++) {
 193                         p0 = &per_cpu_stats[current][j];
 194                         if (p0->irq_name[0] != '\0') {
 195                                 q0 = &per_cpu_stats[prev][j];
 196                                 if (strcmp(p0->irq_name, q0->irq_name) != 0) {
 197                                         /* Strings are different */
 198                                         break;
 199                                 }
 200                         }
 201                 }
 202         }
 203
 204         /* Print header */
 205         printf("\n%-11s  CPU", prev_str);
 206         {
 207                 /* A bit complex code to "buy back" space if one header is too wide.
 208                  * Here's how it looks like. BLOCK_IOPOLL eating too much,
 209                  * and latter headers use smaller width to compensate:
 210                  * ...BLOCK/s BLOCK_IOPOLL/s TASKLET/s SCHED/s HRTIMER/s  RCU/s
 211                  * ...   2.32      0.00      0.01     17.58      0.14    141.96
 212                  */
 213                 int expected_len = 0;
 214                 int printed_len = 0;
 215                 for (j = 0; j < total_irqs; j++) {
 216                         p0 = &per_cpu_stats[current][j];
 217                         if (p0->irq_name[0] != '\0') {
 218                                 int n = (INTRATE_SCRWIDTH-3) - (printed_len - expected_len);
 219                                 printed_len += printf(" %*s/s", n > 0 ? n : 0, skip_whitespace(p0->irq_name));
 220                                 expected_len += INTRATE_SCRWIDTH;
 221                         }
 222                 }
 223         }
 224         bb_putchar('\n');
 225
 226         for (cpu = 1; cpu <= G.cpu_nr; cpu++) {
 227                 /* Check if we want stats about this CPU */
 228                 if (!is_cpu_in_bitmap(cpu) && G.p_option) {
 229                         continue;
 230                 }
 231
 232                 printf("%-11s %4u", current_str, cpu - 1);
 233
 234                 for (j = 0; j < total_irqs; j++) {
 235                         /* IRQ field set only for proc 0 */
 236                         p0 = &per_cpu_stats[current][j];
 237
 238                         /*
 239                          * An empty string for irq name means that
 240                          * interrupt is no longer used.
 241                          */
 242                         if (p0->irq_name[0] != '\0') {
 243                                 offset = j;
 244                                 q0 = &per_cpu_stats[prev][offset];
 245
 246                                 /*
 247                                  * If we want stats for the time since boot
 248                                  * we have p0->irq != q0->irq.
 249                                  */
 250                                 if (strcmp(p0->irq_name, q0->irq_name) != 0
 251                                  && G.interval != 0
 252                                 ) {
 253                                         if (j) {
 254                                                 offset = j - 1;
 255                                                 q0 = &per_cpu_stats[prev][offset];
 256                                         }
 257                                         if (strcmp(p0->irq_name, q0->irq_name) != 0
 258                                          && (j + 1 < total_irqs)
 259                                         ) {
 260                                                 offset = j + 1;
 261                                                 q0 = &per_cpu_stats[prev][offset];
 262                                         }
 263                                 }
 264
 265                                 if (strcmp(p0->irq_name, q0->irq_name) == 0
 266                                  || G.interval == 0
 267                                 ) {
 268                                         struct stats_irqcpu *p, *q;
 269                                         p = &per_cpu_stats[current][(cpu - 1) * total_irqs + j];
 270                                         q = &per_cpu_stats[prev][(cpu - 1) * total_irqs + offset];
 271                                         printf("%"INTRATE_SCRWIDTH_STR".2f",
 272                                                 (double)(p->interrupt - q->interrupt) / itv * G.hz);
 273                                 } else {
 274                                         printf("        N/A");
 275                                 }
 276                         }
 277                 }
 278                 bb_putchar('\n');
 279         }
 280 }
 281
 282 static data_t get_per_cpu_interval(const struct stats_cpu *scc,
 283                 const struct stats_cpu *scp)
 284 {
 285         return ((scc->cpu_user + scc->cpu_nice +
 286                  scc->cpu_system + scc->cpu_iowait +
 287                  scc->cpu_idle + scc->cpu_steal +
 288                  scc->cpu_irq + scc->cpu_softirq) -
 289                 (scp->cpu_user + scp->cpu_nice +
 290                  scp->cpu_system + scp->cpu_iowait +
 291                  scp->cpu_idle + scp->cpu_steal +
 292                  scp->cpu_irq + scp->cpu_softirq));
 293 }
 294
 295 static void print_stats_cpu_struct(const struct stats_cpu *p,
 296                 const struct stats_cpu *c,
 297                 data_t itv)
 298 {
 299         printf(" %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f\n",
 300                 percent_value(p->cpu_user - p->cpu_guest,
 301                 /**/                          c->cpu_user - c->cpu_guest, itv),
 302                 percent_value(p->cpu_nice   , c->cpu_nice   , itv),
 303                 percent_value(p->cpu_system , c->cpu_system , itv),
 304                 percent_value(p->cpu_iowait , c->cpu_iowait , itv),
 305                 percent_value(p->cpu_irq    , c->cpu_irq    , itv),
 306                 percent_value(p->cpu_softirq, c->cpu_softirq, itv),
 307                 percent_value(p->cpu_steal  , c->cpu_steal  , itv),
 308                 percent_value(p->cpu_guest  , c->cpu_guest  , itv),
 309                 percent_value(p->cpu_idle   , c->cpu_idle   , itv)
 310         );
 311 }
 312
 313 static void write_stats_core(int prev, int current,
 314                 const char *prev_str, const char *current_str)
 315 {
 316         struct stats_cpu *scc, *scp;
 317         data_t itv, global_itv;
 318         int cpu;
 319
 320         /* Compute time interval */
 321         itv = global_itv = jiffies_diff(G.global_uptime[prev], G.global_uptime[current]);
 322
 323         /* Reduce interval to one CPU */
 324         if (G.cpu_nr > 1)
 325                 itv = jiffies_diff(G.per_cpu_uptime[prev], G.per_cpu_uptime[current]);
 326
 327         /* Print CPU stats */
 328         if (display_opt(D_CPU)) {
 329
 330                 /* This is done exactly once */
 331                 if (!G.header_done) {
 332                         printf("\n%-11s  CPU    %%usr   %%nice    %%sys %%iowait    %%irq   %%soft  %%steal  %%guest   %%idle\n",
 333                                 prev_str
 334                         );
 335                         G.header_done = 1;
 336                 }
 337
 338                 for (cpu = 0; cpu <= G.cpu_nr; cpu++) {
 339                         data_t per_cpu_itv;
 340
 341                         /* Print stats about this particular CPU? */
 342                         if (!is_cpu_in_bitmap(cpu))
 343                                 continue;
 344
 345                         scc = &G.st_cpu[current][cpu];
 346                         scp = &G.st_cpu[prev][cpu];
 347                         per_cpu_itv = global_itv;
 348
 349                         printf((cpu ? "%-11s %4u" : "%-11s  all"), current_str, cpu - 1);
 350                         if (cpu) {
 351                                 double idle;
 352                                 /*
 353                                  * If the CPU is offline, then it isn't in /proc/stat,
 354                                  * so all values are 0.
 355                                  * NB: Guest time is already included in user time.
 356                                  */
 357                                 if ((scc->cpu_user | scc->cpu_nice | scc->cpu_system |
 358                                      scc->cpu_iowait | scc->cpu_idle | scc->cpu_steal |
 359                                      scc->cpu_irq | scc->cpu_softirq) == 0
 360                                 ) {
 361                                         /*
 362                                          * Set current struct fields to values from prev.
 363                                          * iteration. Then their values won't jump from
 364                                          * zero, when the CPU comes back online.
 365                                          */
 366                                         *scc = *scp;
 367                                         idle = 0.0;
 368                                         goto print_zeros;
 369                                 }
 370                                 /* Compute interval again for current proc */
 371                                 per_cpu_itv = get_per_cpu_interval(scc, scp);
 372                                 if (per_cpu_itv == 0) {
 373                                         /*
 374                                          * If the CPU is tickless then there is no change in CPU values
 375                                          * but the sum of values is not zero.
 376                                          */
 377                                         idle = 100.0;
 378  print_zeros:
 379                                         printf(" %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f\n",
 380                                                 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, idle);
 381                                         continue;
 382                                 }
 383                         }
 384                         print_stats_cpu_struct(scp, scc, per_cpu_itv);
 385                 }
 386         }
 387
 388         /* Print total number of IRQs per CPU */
 389         if (display_opt(D_IRQ_SUM)) {
 390
 391                 /* Print average header, this is done exactly once */
 392                 if (!G.avg_header_done) {
 393                         printf("\n%-11s  CPU    intr/s\n", prev_str);
 394                         G.avg_header_done = 1;
 395                 }
 396
 397                 for (cpu = 0; cpu <= G.cpu_nr; cpu++) {
 398                         data_t per_cpu_itv;
 399
 400                         /* Print stats about this CPU? */
 401                         if (!is_cpu_in_bitmap(cpu))
 402                                 continue;
 403
 404                         per_cpu_itv = itv;
 405                         printf((cpu ? "%-11s %4u" : "%-11s  all"), current_str, cpu - 1);
 406                         if (cpu) {
 407                                 scc = &G.st_cpu[current][cpu];
 408                                 scp = &G.st_cpu[prev][cpu];
 409                                 /* Compute interval again for current proc */
 410                                 per_cpu_itv = get_per_cpu_interval(scc, scp);
 411                                 if (per_cpu_itv == 0) {
 412                                         printf(" %9.2f\n", 0.0);
 413                                         continue;
 414                                 }
 415                         }
 416                         printf(" %9.2f\n", hz_value(G.st_irq[prev][cpu].irq_nr, G.st_irq[current][cpu].irq_nr, per_cpu_itv));
 417                 }
 418         }
 419
 420         if (display_opt(D_IRQ_CPU)) {
 421                 write_irqcpu_stats(G.st_irqcpu, G.irqcpu_nr,
 422                                 itv,
 423                                 prev, current,
 424                                 prev_str, current_str
 425                 );
 426         }
 427
 428         if (display_opt(D_SOFTIRQS)) {
 429                 write_irqcpu_stats(G.st_softirqcpu, G.softirqcpu_nr,
 430                                 itv,
 431                                 prev, current,
 432                                 prev_str, current_str
 433                 );
 434         }
 435 }
 436
 437 /*
 438  * Print the statistics
 439  */
 440 static void write_stats(int current)
 441 {
 442         char prev_time[16];
 443         char curr_time[16];
 444
 445         strftime(prev_time, sizeof(prev_time), "%X", &G.timestamp[!current]);
 446         strftime(curr_time, sizeof(curr_time), "%X", &G.timestamp[current]);
 447
 448         write_stats_core(!current, current, prev_time, curr_time);
 449 }
 450
 451 static void write_stats_avg(int current)
 452 {
 453         write_stats_core(2, current, "Average:", "Average:");
 454 }
 455
 456 /*
 457  * Read CPU statistics
 458  */
 459 static void get_cpu_statistics(struct stats_cpu *cpu, data_t *up, data_t *up0)
 460 {
 461         FILE *fp;
 462         char buf[1024];
 463
 464         fp = xfopen_for_read(PROCFS_STAT);
 465
 466         while (fgets(buf, sizeof(buf), fp)) {
 467                 data_t sum;
 468                 unsigned cpu_number;
 469                 struct stats_cpu *cp;
 470
 471                 if (!starts_with_cpu(buf))
 472                         continue; /* not "cpu" */
 473
 474                 cp = cpu; /* for "cpu " case */
 475                 if (buf[3] != ' ') {
 476                         /* "cpuN " */
 477                         if (G.cpu_nr == 0
 478                          || sscanf(buf + 3, "%u ", &cpu_number) != 1
 479                          || cpu_number >= G.cpu_nr
 480                         ) {
 481                                 continue;
 482                         }
 483                         cp = &cpu[cpu_number + 1];
 484                 }
 485
 486                 /* Read the counters, save them */
 487                 /* Not all fields have to be present */
 488                 memset(cp, 0, sizeof(*cp));
 489                 sscanf(buf, "%*s"
 490                         " %"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u"
 491                         " %"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u"
 492                         " %"FMT_DATA"u %"FMT_DATA"u %"FMT_DATA"u",
 493                         &cp->cpu_user, &cp->cpu_nice, &cp->cpu_system,
 494                         &cp->cpu_idle, &cp->cpu_iowait, &cp->cpu_irq,
 495                         &cp->cpu_softirq, &cp->cpu_steal, &cp->cpu_guest
 496                 );
 497                 /*
 498                  * Compute uptime in jiffies (1/HZ), it'll be the sum of
 499                  * individual CPU's uptimes.
 500                  * NB: We have to omit cpu_guest, because cpu_user includes it.
 501                  */
 502                 sum = cp->cpu_user + cp->cpu_nice + cp->cpu_system +
 503                         cp->cpu_idle + cp->cpu_iowait + cp->cpu_irq +
 504                         cp->cpu_softirq + cp->cpu_steal;
 505
 506                 if (buf[3] == ' ') {
 507                         /* "cpu " */
 508                         *up = sum;
 509                 } else {
 510                         /* "cpuN " */
 511                         if (cpu_number == 0 && *up0 != 0) {
 512                                 /* Compute uptime of single CPU */
 513                                 *up0 = sum;
 514                         }
 515                 }
 516         }
 517         fclose(fp);
 518 }
 519
 520 /*
 521  * Read IRQs from /proc/stat
 522  */
 523 static void get_irqs_from_stat(struct stats_irq *irq)
 524 {
 525         FILE *fp;
 526         char buf[1024];
 527
 528         fp = fopen_for_read(PROCFS_STAT);
 529         if (!fp)
 530                 return;
 531
 532         while (fgets(buf, sizeof(buf), fp)) {
 533                 if (strncmp(buf, "intr ", 5) == 0)
 534                         /* Read total number of IRQs since system boot */
 535                         sscanf(buf + 5, "%"FMT_DATA"u", &irq->irq_nr);
 536         }
 537
 538         fclose(fp);
 539 }
 540
 541 /*
 542  * Read stats from /proc/interrupts or /proc/softirqs
 543  */
 544 static void get_irqs_from_interrupts(const char *fname,
 545                 struct stats_irqcpu *per_cpu_stats[],
 546                 int irqs_per_cpu, int current)
 547 {
 548         FILE *fp;
 549         struct stats_irq *irq_i;
 550         struct stats_irqcpu *ic;
 551         char *buf;
 552         unsigned buflen;
 553         unsigned cpu;
 554         unsigned irq;
 555         int cpu_index[G.cpu_nr];
 556         int iindex;
 557         int len, digit;
 558
 559         for (cpu = 1; cpu <= G.cpu_nr; cpu++) {
 560                 irq_i = &G.st_irq[current][cpu];
 561                 irq_i->irq_nr = 0;
 562         }
 563
 564         fp = fopen_for_read(fname);
 565         if (!fp)
 566                 return;
 567
 568         buflen = INTERRUPTS_LINE + 16 * G.cpu_nr;
 569         buf = xmalloc(buflen);
 570
 571         /* Parse header and determine, which CPUs are online */
 572         iindex = 0;
 573         while (fgets(buf, buflen, fp)) {
 574                 char *cp, *next;
 575                 next = buf;
 576                 while ((cp = strstr(next, "CPU")) != NULL
 577                  && iindex < G.cpu_nr
 578                 ) {
 579                         cpu = strtoul(cp + 3, &next, 10);
 580                         cpu_index[iindex++] = cpu;
 581                 }
 582                 if (iindex) /* We found header */
 583                         break;
 584         }
 585
 586         irq = 0;
 587         while (fgets(buf, buflen, fp)
 588          && irq < irqs_per_cpu
 589         ) {
 590                 char *cp;
 591                 /* Skip over "<irq>:" */
 592                 cp = strchr(buf, ':');
 593                 if (!cp)
 594                         continue;
 595
 596                 ic = &per_cpu_stats[current][irq];
 597                 len = cp - buf;
 598                 if (len >= sizeof(ic->irq_name)) {
 599                         len = sizeof(ic->irq_name) - 1;
 600                 }
 601                 safe_strncpy(ic->irq_name, buf, len + 1);
 602                 //bb_error_msg("%s: irq%d:'%s' buf:'%s'", fname, irq, ic->irq_name, buf);
 603                 digit = isdigit(buf[len - 1]);
 604                 cp++;
 605
 606                 for (cpu = 0; cpu < iindex; cpu++) {
 607                         char *next;
 608                         ic = &per_cpu_stats[current][cpu_index[cpu] * irqs_per_cpu + irq];
 609                         irq_i = &G.st_irq[current][cpu_index[cpu] + 1];
 610                         ic->interrupt = strtoul(cp, &next, 10);
 611                         if (digit) {
 612                                 /* Do not count non-numerical IRQs */
 613                                 irq_i->irq_nr += ic->interrupt;
 614                         }
 615                         cp = next;
 616                 }
 617                 irq++;
 618         }
 619         fclose(fp);
 620         free(buf);
 621
 622         while (irq < irqs_per_cpu) {
 623                 /* Number of interrupts per CPU has changed */
 624                 ic = &per_cpu_stats[current][irq];
 625                 ic->irq_name[0] = '\0'; /* False interrupt */
 626                 irq++;
 627         }
 628 }
 629
 630 static void get_uptime(data_t *uptime)
 631 {
 632         FILE *fp;
 633         char buf[sizeof(long)*3 * 2 + 4]; /* enough for long.long */
 634         unsigned long uptime_sec, decimal;
 635
 636         fp = fopen_for_read(PROCFS_UPTIME);
 637         if (!fp)
 638                 return;
 639         if (fgets(buf, sizeof(buf), fp)) {
 640                 if (sscanf(buf, "%lu.%lu", &uptime_sec, &decimal) == 2) {
 641                         *uptime = (data_t)uptime_sec * G.hz + decimal * G.hz / 100;
 642                 }
 643         }
 644
 645         fclose(fp);
 646 }
 647
 648 static void get_localtime(struct tm *tm)
 649 {
 650         time_t timer;
 651         time(&timer);
 652         localtime_r(&timer, tm);
 653 }
 654
 655 static void alarm_handler(int sig UNUSED_PARAM)
 656 {
 657         signal(SIGALRM, alarm_handler);
 658         alarm(G.interval);
 659 }
 660
 661 static void main_loop(void)
 662 {
 663         unsigned current;
 664         unsigned cpus;
 665
 666         /* Read the stats */
 667         if (G.cpu_nr > 1) {
 668                 G.per_cpu_uptime[0] = 0;
 669                 get_uptime(&G.per_cpu_uptime[0]);
 670         }
 671
 672         get_cpu_statistics(G.st_cpu[0], &G.global_uptime[0], &G.per_cpu_uptime[0]);
 673
 674         if (display_opt(D_IRQ_SUM))
 675                 get_irqs_from_stat(G.st_irq[0]);
 676
 677         if (display_opt(D_IRQ_SUM | D_IRQ_CPU))
 678                 get_irqs_from_interrupts(PROCFS_INTERRUPTS, G.st_irqcpu,
 679                                         G.irqcpu_nr, 0);
 680
 681         if (display_opt(D_SOFTIRQS))
 682                 get_irqs_from_interrupts(PROCFS_SOFTIRQS, G.st_softirqcpu,
 683                                         G.softirqcpu_nr, 0);
 684
 685         if (G.interval == 0) {
 686                 /* Display since boot time */
 687                 cpus = G.cpu_nr + 1;
 688                 G.timestamp[1] = G.timestamp[0];
 689                 memset(G.st_cpu[1], 0, sizeof(G.st_cpu[1][0]) * cpus);
 690                 memset(G.st_irq[1], 0, sizeof(G.st_irq[1][0]) * cpus);
 691                 memset(G.st_irqcpu[1], 0, sizeof(G.st_irqcpu[1][0]) * cpus * G.irqcpu_nr);
 692                 memset(G.st_softirqcpu[1], 0, sizeof(G.st_softirqcpu[1][0]) * cpus * G.softirqcpu_nr);
 693
 694                 write_stats(0);
 695
 696                 /* And we're done */
 697                 return;
 698         }
 699
 700         /* Set a handler for SIGALRM */
 701         alarm_handler(0);
 702
 703         /* Save the stats we already have. We need them to compute the average */
 704         G.timestamp[2] = G.timestamp[0];
 705         G.global_uptime[2] = G.global_uptime[0];
 706         G.per_cpu_uptime[2] = G.per_cpu_uptime[0];
 707         cpus = G.cpu_nr + 1;
 708         memcpy(G.st_cpu[2], G.st_cpu[0], sizeof(G.st_cpu[0][0]) * cpus);
 709         memcpy(G.st_irq[2], G.st_irq[0], sizeof(G.st_irq[0][0]) * cpus);
 710         memcpy(G.st_irqcpu[2], G.st_irqcpu[0], sizeof(G.st_irqcpu[0][0]) * cpus * G.irqcpu_nr);
 711         if (display_opt(D_SOFTIRQS)) {
 712                 memcpy(G.st_softirqcpu[2], G.st_softirqcpu[0],
 713                         sizeof(G.st_softirqcpu[0][0]) * cpus * G.softirqcpu_nr);
 714         }
 715
 716         current = 1;
 717         while (1) {
 718                 /* Suspend until a signal is received */
 719                 pause();
 720
 721                 /* Set structures to 0 to distinguish off/online CPUs */
 722                 memset(&G.st_cpu[current][/*cpu:*/ 1], 0, sizeof(G.st_cpu[0][0]) * G.cpu_nr);
 723
 724                 get_localtime(&G.timestamp[current]);
 725
 726                 /* Read stats */
 727                 if (G.cpu_nr > 1) {
 728                         G.per_cpu_uptime[current] = 0;
 729                         get_uptime(&G.per_cpu_uptime[current]);
 730                 }
 731                 get_cpu_statistics(G.st_cpu[current], &G.global_uptime[current], &G.per_cpu_uptime[current]);
 732
 733                 if (display_opt(D_IRQ_SUM))
 734                         get_irqs_from_stat(G.st_irq[current]);
 735
 736                 if (display_opt(D_IRQ_SUM | D_IRQ_CPU))
 737                         get_irqs_from_interrupts(PROCFS_INTERRUPTS, G.st_irqcpu,
 738                                         G.irqcpu_nr, current);
 739
 740                 if (display_opt(D_SOFTIRQS))
 741                         get_irqs_from_interrupts(PROCFS_SOFTIRQS,
 742                                         G.st_softirqcpu,
 743                                         G.softirqcpu_nr, current);
 744
 745                 write_stats(current);
 746
 747                 if (G.count > 0) {
 748                         if (--G.count == 0)
 749                                 break;
 750                 }
 751
 752                 current ^= 1;
 753         }
 754
 755         /* Print average statistics */
 756         write_stats_avg(current);
 757 }
 758
 759 /* Initialization */
 760
 761 /* Get number of clock ticks per sec */
 762 static ALWAYS_INLINE unsigned get_hz(void)
 763 {
 764         return sysconf(_SC_CLK_TCK);
 765 }
 766
 767 static void alloc_struct(int cpus)
 768 {
 769         int i;
 770         for (i = 0; i < 3; i++) {
 771                 G.st_cpu[i] = xzalloc(sizeof(G.st_cpu[i][0]) * cpus);
 772                 G.st_irq[i] = xzalloc(sizeof(G.st_irq[i][0]) * cpus);
 773                 G.st_irqcpu[i] = xzalloc(sizeof(G.st_irqcpu[i][0]) * cpus * G.irqcpu_nr);
 774                 G.st_softirqcpu[i] = xzalloc(sizeof(G.st_softirqcpu[i][0]) * cpus * G.softirqcpu_nr);
 775         }
 776         G.cpu_bitmap_len = (cpus >> 3) + 1;
 777         G.cpu_bitmap = xzalloc(G.cpu_bitmap_len);
 778 }
 779
 780 static void print_header(struct tm *t)
 781 {
 782         char cur_date[16];
 783         struct utsname uts;
 784
 785         /* Get system name, release number and hostname */
 786         uname(&uts);
 787
 788         strftime(cur_date, sizeof(cur_date), "%x", t);
 789
 790         printf("%s %s (%s)\t%s\t_%s_\t(%u CPU)\n",
 791                 uts.sysname, uts.release, uts.nodename, cur_date, uts.machine, G.cpu_nr);
 792 }
 793
 794 /*
 795  * Get number of processors in /sys
 796  */
 797 static int get_sys_cpu_nr(void)
 798 {
 799         DIR *dir;
 800         struct dirent *d;
 801         struct stat buf;
 802         char line[MAX_PF_NAME];
 803         int proc_nr = 0;
 804
 805         dir = opendir(SYSFS_DEVCPU);
 806         if (!dir)
 807                 return 0;       /* /sys not mounted */
 808
 809         /* Get current file entry */
 810         while ((d = readdir(dir)) != NULL) {
 811                 if (starts_with_cpu(d->d_name) && isdigit(d->d_name[3])) {
 812                         snprintf(line, MAX_PF_NAME, "%s/%s", SYSFS_DEVCPU,
 813                                  d->d_name);
 814                         line[MAX_PF_NAME - 1] = '\0';
 815                         /* Get information about file */
 816                         if (stat(line, &buf) < 0)
 817                                 continue;
 818                         /* If found 'cpuN', we have one more processor */
 819                         if (S_ISDIR(buf.st_mode))
 820                                 proc_nr++;
 821                 }
 822         }
 823
 824         closedir(dir);
 825         return proc_nr;
 826 }
 827
 828 /*
 829  * Get number of processors in /proc/stat
 830  * Return value '0' means one CPU and non SMP kernel.
 831  * Otherwise N means N processor(s) and SMP kernel.
 832  */
 833 static int get_proc_cpu_nr(void)
 834 {
 835         FILE *fp;
 836         char line[256];
 837         int proc_nr = -1;
 838
 839         fp = xfopen_for_read(PROCFS_STAT);
 840         while (fgets(line, sizeof(line), fp)) {
 841                 if (!starts_with_cpu(line)) {
 842                         if (proc_nr >= 0)
 843                                 break; /* we are past "cpuN..." lines */
 844                         continue;
 845                 }
 846                 if (line[3] != ' ') { /* "cpuN" */
 847                         int num_proc;
 848                         if (sscanf(line + 3, "%u", &num_proc) == 1
 849                          && num_proc > proc_nr
 850                         ) {
 851                                 proc_nr = num_proc;
 852                         }
 853                 }
 854         }
 855
 856         fclose(fp);
 857         return proc_nr + 1;
 858 }
 859
 860 static int get_cpu_nr(void)
 861 {
 862         int n;
 863
 864         /* Try to use /sys, if possible */
 865         n = get_sys_cpu_nr();
 866         if (n == 0)
 867                 /* Otherwise use /proc/stat */
 868                 n = get_proc_cpu_nr();
 869
 870         return n;
 871 }
 872
 873 /*
 874  * Get number of interrupts available per processor
 875  */
 876 static int get_irqcpu_nr(const char *f, int max_irqs)
 877 {
 878         FILE *fp;
 879         char *line;
 880         unsigned linelen;
 881         unsigned irq;
 882
 883         fp = fopen_for_read(f);
 884         if (!fp)                /* No interrupts file */
 885                 return 0;
 886
 887         linelen = INTERRUPTS_LINE + 16 * G.cpu_nr;
 888         line = xmalloc(linelen);
 889
 890         irq = 0;
 891         while (fgets(line, linelen, fp)
 892          && irq < max_irqs
 893         ) {
 894                 int p = strcspn(line, ":");
 895                 if ((p > 0) && (p < 16))
 896                         irq++;
 897         }
 898
 899         fclose(fp);
 900         free(line);
 901
 902         return irq;
 903 }
 904
 905 //usage:#define mpstat_trivial_usage
 906 //usage:       "[-A] [-I SUM|CPU|ALL|SCPU] [-u] [-P num|ALL] [INTERVAL [COUNT]]"
 907 //usage:#define mpstat_full_usage "\n\n"
 908 //usage:       "Per-processor statistics\n"
 909 //usage:     "\nOptions:"
 910 //usage:     "\n        -A                      Same as -I ALL -u -P ALL"
 911 //usage:     "\n        -I SUM|CPU|ALL|SCPU     Report interrupt statistics"
 912 //usage:     "\n        -P num|ALL              Processor to monitor"
 913 //usage:     "\n        -u                      Report CPU utilization"
 914
 915 int mpstat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 916 int mpstat_main(int UNUSED_PARAM argc, char **argv)
 917 {
 918         char *opt_irq_fmt;
 919         char *opt_set_cpu;
 920         int i, opt;
 921         enum {
 922                 OPT_ALL    = 1 << 0,    /* -A */
 923                 OPT_INTS   = 1 << 1,    /* -I */
 924                 OPT_SETCPU = 1 << 2,    /* -P */
 925                 OPT_UTIL   = 1 << 3,    /* -u */
 926         };
 927
 928         /* Dont buffer data if redirected to a pipe */
 929         setbuf(stdout, NULL);
 930
 931         INIT_G();
 932
 933         G.interval = -1;
 934
 935         /* Get number of processors */
 936         G.cpu_nr = get_cpu_nr();
 937
 938         /* Get number of clock ticks per sec */
 939         G.hz = get_hz();
 940
 941         /* Calculate number of interrupts per processor */
 942         G.irqcpu_nr = get_irqcpu_nr(PROCFS_INTERRUPTS, NR_IRQS) + NR_IRQCPU_PREALLOC;
 943
 944         /* Calculate number of soft interrupts per processor */
 945         G.softirqcpu_nr = get_irqcpu_nr(PROCFS_SOFTIRQS, NR_IRQS) + NR_IRQCPU_PREALLOC;
 946
 947         /* Allocate space for structures. + 1 for global structure. */
 948         alloc_struct(G.cpu_nr + 1);
 949
 950         /* Parse and process arguments */
 951         opt = getopt32(argv, "AI:P:u", &opt_irq_fmt, &opt_set_cpu);
 952         argv += optind;
 953
 954         if (*argv) {
 955                 /* Get interval */
 956                 G.interval = xatoi_u(*argv);
 957                 G.count = -1;
 958                 argv++;
 959                 if (*argv) {
 960                         /* Get count value */
 961                         if (G.interval == 0)
 962                                 bb_show_usage();
 963                         G.count = xatoi_u(*argv);
 964                         //if (*++argv)
 965                         //      bb_show_usage();
 966                 }
 967         }
 968         if (G.interval < 0)
 969                 G.interval = 0;
 970
 971         if (opt & OPT_ALL) {
 972                 G.p_option = 1;
 973                 G.options |= D_CPU + D_IRQ_SUM + D_IRQ_CPU + D_SOFTIRQS;
 974                 /* Select every CPU */
 975                 memset(G.cpu_bitmap, 0xff, G.cpu_bitmap_len);
 976         }
 977
 978         if (opt & OPT_INTS) {
 979                 static const char v[] = {
 980                         D_IRQ_CPU, D_IRQ_SUM, D_SOFTIRQS,
 981                         D_IRQ_SUM + D_IRQ_CPU + D_SOFTIRQS
 982                 };
 983                 i = index_in_strings("CPU\0SUM\0SCPU\0ALL\0", opt_irq_fmt);
 984                 if (i == -1)
 985                         bb_show_usage();
 986                 G.options |= v[i];
 987         }
 988
 989         if ((opt & OPT_UTIL) /* -u? */
 990          || G.options == 0  /* nothing? (use default then) */
 991         ) {
 992                 G.options |= D_CPU;
 993         }
 994
 995         if (opt & OPT_SETCPU) {
 996                 char *t;
 997                 G.p_option = 1;
 998
 999                 for (t = strtok(opt_set_cpu, ","); t; t = strtok(NULL, ",")) {
1000                         if (strcmp(t, "ALL") == 0) {
1001                                 /* Select every CPU */
1002                                 memset(G.cpu_bitmap, 0xff, G.cpu_bitmap_len);
1003                         } else {
1004                                 /* Get CPU number */
1005                                 unsigned n = xatoi_u(t);
1006                                 if (n >= G.cpu_nr)
1007                                         bb_error_msg_and_die("not that many processors");
1008                                 n++;
1009                                 G.cpu_bitmap[n >> 3] |= 1 << (n & 7);
1010                         }
1011                 }
1012         }
1013
1014         if (!G.p_option)
1015                 /* Display global stats */
1016                 G.cpu_bitmap[0] = 1;
1017
1018         /* Get time */
1019         get_localtime(&G.timestamp[0]);
1020
1021         /* Display header */
1022         print_header(&G.timestamp[0]);
1023
1024         /* The main loop */
1025         main_loop();
1026
1027         if (ENABLE_FEATURE_CLEAN_UP) {
1028                 /* Clean up */
1029                 for (i = 0; i < 3; i++) {
1030                         free(G.st_cpu[i]);
1031                         free(G.st_irq[i]);
1032                         free(G.st_irqcpu[i]);
1033                         free(G.st_softirqcpu[i]);
1034                 }
1035                 free(G.cpu_bitmap);
1036                 free(&G);
1037         }
1038
1039         return EXIT_SUCCESS;
1040 }