mono/utils/mono-proclib.c

   1 /*
   2  * Copyright 2008-2011 Novell Inc
   3  * Copyright 2011 Xamarin Inc
   4  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
   5  */
   6
   7 #include "config.h"
   8 #include "utils/mono-proclib.h"
   9 #include "utils/mono-time.h"
  10
  11 #include <stdlib.h>
  12 #include <stdio.h>
  13 #include <string.h>
  14 #include <fcntl.h>
  15 #ifdef HAVE_UNISTD_H
  16 #include <unistd.h>
  17 #endif
  18 #ifdef HAVE_SCHED_GETAFFINITY
  19 #include <sched.h>
  20 #endif
  21
  22 #if defined(_POSIX_VERSION)
  23 #include <sys/errno.h>
  24 #include <sys/param.h>
  25 #include <errno.h>
  26 #ifdef HAVE_SYS_TYPES_H
  27 #include <sys/types.h>
  28 #endif
  29 #ifdef HAVE_SYS_SYSCTL_H
  30 #include <sys/sysctl.h>
  31 #endif
  32 #include <sys/resource.h>
  33 #endif
  34 #if defined(__APPLE__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__)
  35 #include <sys/proc.h>
  36 #if defined(__APPLE__)
  37 #include <mach/mach.h>
  38 #endif
  39 #ifdef HAVE_SYS_USER_H
  40 #include <sys/user.h>
  41 #endif
  42 #ifdef HAVE_STRUCT_KINFO_PROC_KP_PROC
  43 #    define kinfo_starttime_member kp_proc.p_starttime
  44 #    define kinfo_pid_member kp_proc.p_pid
  45 #    define kinfo_name_member kp_proc.p_comm
  46 #elif defined(__NetBSD__)
  47 #    define kinfo_starttime_member p_ustart_sec
  48 #    define kinfo_pid_member p_pid
  49 #    define kinfo_name_member p_comm
  50 #elif defined(__OpenBSD__)
  51 // Can not figure out how to get the proc's start time on OpenBSD
  52 #    undef kinfo_starttime_member
  53 #    define kinfo_pid_member p_pid
  54 #    define kinfo_name_member p_comm
  55 #else
  56 #define kinfo_starttime_member ki_start
  57 #define kinfo_pid_member ki_pid
  58 #define kinfo_name_member ki_comm
  59 #endif
  60 #define USE_SYSCTL 1
  61 #endif
  62
  63 /**
  64  * mono_process_list:
  65  * @size: a pointer to a location where the size of the returned array is stored
  66  *
  67  * Return an array of pid values for the processes currently running on the system.
  68  * The size of the array is stored in @size.
  69  */
  70 gpointer*
  71 mono_process_list (int *size)
  72 {
  73 #if USE_SYSCTL
  74         int res, i;
  75 #ifdef KERN_PROC2
  76         int mib [6];
  77         size_t data_len = sizeof (struct kinfo_proc2) * 400;
  78         struct kinfo_proc2 *processes = g_malloc (data_len);
  79 #else
  80         int mib [4];
  81         size_t data_len = sizeof (struct kinfo_proc) * 16;
  82         struct kinfo_proc *processes;
  83         int limit = 8;
  84 #endif /* KERN_PROC2 */
  85         void **buf = NULL;
  86
  87         if (size)
  88                 *size = 0;
  89
  90 #ifdef KERN_PROC2
  91         if (!processes)
  92                 return NULL;
  93
  94         mib [0] = CTL_KERN;
  95         mib [1] = KERN_PROC2;
  96         mib [2] = KERN_PROC_ALL;
  97         mib [3] = 0;
  98         mib [4] = sizeof(struct kinfo_proc2);
  99         mib [5] = 400; /* XXX */
 100
 101         res = sysctl (mib, 6, processes, &data_len, NULL, 0);
 102         if (res < 0) {
 103                 g_free (processes);
 104                 return NULL;
 105         }
 106 #else
 107         processes = NULL;
 108         while (limit) {
 109                 mib [0] = CTL_KERN;
 110                 mib [1] = KERN_PROC;
 111                 mib [2] = KERN_PROC_ALL;
 112                 mib [3] = 0;
 113
 114                 res = sysctl (mib, 4, NULL, &data_len, NULL, 0);
 115                 if (res)
 116                         return NULL;
 117                 processes = (struct kinfo_proc *) g_malloc (data_len);
 118                 res = sysctl (mib, 4, processes, &data_len, NULL, 0);
 119                 if (res < 0) {
 120                         g_free (processes);
 121                         if (errno != ENOMEM)
 122                                 return NULL;
 123                         limit --;
 124                 } else {
 125                         break;
 126                 }
 127         }
 128 #endif /* KERN_PROC2 */
 129
 130 #ifdef KERN_PROC2
 131         res = data_len/sizeof (struct kinfo_proc2);
 132 #else
 133         res = data_len/sizeof (struct kinfo_proc);
 134 #endif /* KERN_PROC2 */
 135         buf = (void **) g_realloc (buf, res * sizeof (void*));
 136         for (i = 0; i < res; ++i)
 137                 buf [i] = GINT_TO_POINTER (processes [i].kinfo_pid_member);
 138         g_free (processes);
 139         if (size)
 140                 *size = res;
 141         return buf;
 142 #elif defined(__HAIKU__)
 143         /* FIXME: Add back the code from 9185fcc305e43428d0f40f3ee37c8a405d41c9ae */
 144         g_assert_not_reached ();
 145         return NULL;
 146 #else
 147         const char *name;
 148         void **buf = NULL;
 149         int count = 0;
 150         int i = 0;
 151         GDir *dir = g_dir_open ("/proc/", 0, NULL);
 152         if (!dir) {
 153                 if (size)
 154                         *size = 0;
 155                 return NULL;
 156         }
 157         while ((name = g_dir_read_name (dir))) {
 158                 int pid;
 159                 char *nend;
 160                 pid = strtol (name, &nend, 10);
 161                 if (pid <= 0 || nend == name || *nend)
 162                         continue;
 163                 if (i >= count) {
 164                         if (!count)
 165                                 count = 16;
 166                         else
 167                                 count *= 2;
 168                         buf = (void **)g_realloc (buf, count * sizeof (void*));
 169                 }
 170                 buf [i++] = GINT_TO_POINTER (pid);
 171         }
 172         g_dir_close (dir);
 173         if (size)
 174                 *size = i;
 175         return buf;
 176 #endif
 177 }
 178
 179 static G_GNUC_UNUSED char*
 180 get_pid_status_item_buf (int pid, const char *item, char *rbuf, int blen, MonoProcessError *error)
 181 {
 182         char buf [256];
 183         char *s;
 184         FILE *f;
 185         size_t len = strlen (item);
 186
 187         g_snprintf (buf, sizeof (buf), "/proc/%d/status", pid);
 188         f = fopen (buf, "r");
 189         if (!f) {
 190                 if (error)
 191                         *error = MONO_PROCESS_ERROR_NOT_FOUND;
 192                 return NULL;
 193         }
 194         while ((s = fgets (buf, sizeof (buf), f))) {
 195                 if (*item != *buf)
 196                         continue;
 197                 if (strncmp (buf, item, len))
 198                         continue;
 199                 s = buf + len;
 200                 while (g_ascii_isspace (*s)) s++;
 201                 if (*s++ != ':')
 202                         continue;
 203                 while (g_ascii_isspace (*s)) s++;
 204                 fclose (f);
 205                 len = strlen (s);
 206                 strncpy (rbuf, s, MIN (len, blen));
 207                 rbuf [MIN (len, blen) - 1] = 0;
 208                 if (error)
 209                         *error = MONO_PROCESS_ERROR_NONE;
 210                 return rbuf;
 211         }
 212         fclose (f);
 213         if (error)
 214                 *error = MONO_PROCESS_ERROR_OTHER;
 215         return NULL;
 216 }
 217
 218 #if USE_SYSCTL
 219
 220 #ifdef KERN_PROC2
 221 #define KINFO_PROC struct kinfo_proc2
 222 #else
 223 #define KINFO_PROC struct kinfo_proc
 224 #endif
 225
 226 static gboolean
 227 sysctl_kinfo_proc (gpointer pid, KINFO_PROC* processi)
 228 {
 229         int res;
 230         size_t data_len = sizeof (KINFO_PROC);
 231
 232 #ifdef KERN_PROC2
 233         int mib [6];
 234         mib [0] = CTL_KERN;
 235         mib [1] = KERN_PROC2;
 236         mib [2] = KERN_PROC_PID;
 237         mib [3] = GPOINTER_TO_UINT (pid);
 238         mib [4] = sizeof(KINFO_PROC);
 239         mib [5] = 400; /* XXX */
 240
 241         res = sysctl (mib, 6, processi, &data_len, NULL, 0);
 242 #else
 243         int mib [4];
 244         mib [0] = CTL_KERN;
 245         mib [1] = KERN_PROC;
 246         mib [2] = KERN_PROC_PID;
 247         mib [3] = GPOINTER_TO_UINT (pid);
 248
 249         res = sysctl (mib, 4, processi, &data_len, NULL, 0);
 250 #endif /* KERN_PROC2 */
 251
 252         if (res < 0 || data_len != sizeof (KINFO_PROC))
 253                 return FALSE;
 254
 255         return TRUE;
 256 }
 257 #endif /* USE_SYSCTL */
 258
 259 /**
 260  * mono_process_get_name:
 261  * @pid: pid of the process
 262  * @buf: byte buffer where to store the name of the prcoess
 263  * @len: size of the buffer @buf
 264  *
 265  * Return the name of the process identified by @pid, storing it
 266  * inside @buf for a maximum of len bytes (including the terminating 0).
 267  */
 268 char*
 269 mono_process_get_name (gpointer pid, char *buf, int len)
 270 {
 271 #if USE_SYSCTL
 272         KINFO_PROC processi;
 273
 274         memset (buf, 0, len);
 275
 276         if (sysctl_kinfo_proc (pid, &processi))
 277                 strncpy (buf, processi.kinfo_name_member, len - 1);
 278
 279         return buf;
 280 #else
 281         char fname [128];
 282         FILE *file;
 283         char *p;
 284         size_t r;
 285         sprintf (fname, "/proc/%d/cmdline", GPOINTER_TO_INT (pid));
 286         buf [0] = 0;
 287         file = fopen (fname, "r");
 288         if (!file)
 289                 return buf;
 290         r = fread (buf, 1, len - 1, file);
 291         fclose (file);
 292         buf [r] = 0;
 293         p = strrchr (buf, '/');
 294         if (p)
 295                 return p + 1;
 296         if (r == 0) {
 297                 return get_pid_status_item_buf (GPOINTER_TO_INT (pid), "Name", buf, len, NULL);
 298         }
 299         return buf;
 300 #endif
 301 }
 302
 303 void
 304 mono_process_get_times (gpointer pid, gint64 *start_time, gint64 *user_time, gint64 *kernel_time)
 305 {
 306         if (user_time)
 307                 *user_time = mono_process_get_data (pid, MONO_PROCESS_USER_TIME);
 308
 309         if (kernel_time)
 310                 *kernel_time = mono_process_get_data (pid, MONO_PROCESS_SYSTEM_TIME);
 311
 312         if (start_time) {
 313                 *start_time = 0;
 314
 315 #if USE_SYSCTL && defined(kinfo_starttime_member)
 316                 {
 317                         KINFO_PROC processi;
 318
 319                         if (sysctl_kinfo_proc (pid, &processi)) {
 320 #if defined(__NetBSD__)
 321                                 struct timeval tv;
 322                                 tv.tv_sec = processi.kinfo_starttime_member;
 323                                 tv.tv_usec = processi.p_ustart_usec;
 324                                 *start_time = mono_100ns_datetime_from_timeval(tv);
 325 #else
 326                                 *start_time = mono_100ns_datetime_from_timeval (processi.kinfo_starttime_member);
 327 #endif
 328                         }
 329                 }
 330 #endif
 331
 332                 if (*start_time == 0) {
 333                         static guint64 boot_time = 0;
 334                         if (!boot_time)
 335                                 boot_time = mono_100ns_datetime () - mono_msec_boottime () * 10000;
 336
 337                         *start_time = boot_time + mono_process_get_data (pid, MONO_PROCESS_ELAPSED);
 338                 }
 339         }
 340 }
 341
 342 /*
 343  * /proc/pid/stat format:
 344  * pid (cmdname) S
 345  *      [0] ppid pgid sid tty_nr tty_pgrp flags min_flt cmin_flt maj_flt cmaj_flt
 346  *      [10] utime stime cutime cstime prio nice threads 0 start_time vsize
 347  *      [20] rss rsslim start_code end_code start_stack esp eip pending blocked sigign
 348  *      [30] sigcatch wchan 0 0 exit_signal cpu rt_prio policy
 349  */
 350
 351 #define RET_ERROR(err) do {     \
 352                 if (error) *error = (err);      \
 353                 return 0;                       \
 354         } while (0)
 355
 356 static gint64
 357 get_process_stat_item (int pid, int pos, int sum, MonoProcessError *error)
 358 {
 359 #if defined(__APPLE__)
 360         double process_user_time = 0, process_system_time = 0;//, process_percent = 0;
 361         task_t task;
 362         struct task_basic_info t_info;
 363         mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT, th_count;
 364         thread_array_t th_array;
 365         size_t i;
 366         kern_return_t ret;
 367
 368         if (pid == getpid ()) {
 369                 /* task_for_pid () doesn't work on ios, even for the current process */
 370                 task = mach_task_self ();
 371         } else {
 372                 do {
 373                         ret = task_for_pid (mach_task_self (), pid, &task);
 374                 } while (ret == KERN_ABORTED);
 375
 376                 if (ret != KERN_SUCCESS)
 377                         RET_ERROR (MONO_PROCESS_ERROR_NOT_FOUND);
 378         }
 379
 380         do {
 381                 ret = task_info (task, TASK_BASIC_INFO, (task_info_t)&t_info, &t_info_count);
 382         } while (ret == KERN_ABORTED);
 383
 384         if (ret != KERN_SUCCESS) {
 385                 if (pid != getpid ())
 386                         mach_port_deallocate (mach_task_self (), task);
 387                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 388         }
 389
 390         do {
 391                 ret = task_threads (task, &th_array, &th_count);
 392         } while (ret == KERN_ABORTED);
 393
 394         if (ret  != KERN_SUCCESS) {
 395                 if (pid != getpid ())
 396                         mach_port_deallocate (mach_task_self (), task);
 397                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 398         }
 399
 400         for (i = 0; i < th_count; i++) {
 401                 double thread_user_time, thread_system_time;//, thread_percent;
 402
 403                 struct thread_basic_info th_info;
 404                 mach_msg_type_number_t th_info_count = THREAD_BASIC_INFO_COUNT;
 405                 do {
 406                         ret = thread_info(th_array[i], THREAD_BASIC_INFO, (thread_info_t)&th_info, &th_info_count);
 407                 } while (ret == KERN_ABORTED);
 408
 409                 if (ret == KERN_SUCCESS) {
 410                         thread_user_time = th_info.user_time.seconds + th_info.user_time.microseconds / 1e6;
 411                         thread_system_time = th_info.system_time.seconds + th_info.system_time.microseconds / 1e6;
 412                         //thread_percent = (double)th_info.cpu_usage / TH_USAGE_SCALE;
 413
 414                         process_user_time += thread_user_time;
 415                         process_system_time += thread_system_time;
 416                         //process_percent += th_percent;
 417                 }
 418         }
 419
 420         for (i = 0; i < th_count; i++)
 421                 mach_port_deallocate(task, th_array[i]);
 422
 423         if (pid != getpid ())
 424                 mach_port_deallocate (mach_task_self (), task);
 425
 426         process_user_time += t_info.user_time.seconds + t_info.user_time.microseconds / 1e6;
 427         process_system_time += t_info.system_time.seconds + t_info.system_time.microseconds / 1e6;
 428
 429         if (pos == 10 && sum == TRUE)
 430                 return (gint64)((process_user_time + process_system_time) * 10000000);
 431         else if (pos == 10)
 432                 return (gint64)(process_user_time * 10000000);
 433         else if (pos == 11)
 434                 return (gint64)(process_system_time * 10000000);
 435
 436         return 0;
 437 #else
 438         char buf [512];
 439         char *s, *end;
 440         FILE *f;
 441         size_t len;
 442         int i;
 443         gint64 value;
 444
 445         g_snprintf (buf, sizeof (buf), "/proc/%d/stat", pid);
 446         f = fopen (buf, "r");
 447         if (!f)
 448                 RET_ERROR (MONO_PROCESS_ERROR_NOT_FOUND);
 449         len = fread (buf, 1, sizeof (buf), f);
 450         fclose (f);
 451         if (len <= 0)
 452                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 453         s = strchr (buf, ')');
 454         if (!s)
 455                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 456         s++;
 457         while (g_ascii_isspace (*s)) s++;
 458         if (!*s)
 459                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 460         /* skip the status char */
 461         while (*s && !g_ascii_isspace (*s)) s++;
 462         if (!*s)
 463                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 464         for (i = 0; i < pos; ++i) {
 465                 while (g_ascii_isspace (*s)) s++;
 466                 if (!*s)
 467                         RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 468                 while (*s && !g_ascii_isspace (*s)) s++;
 469                 if (!*s)
 470                         RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 471         }
 472         /* we are finally at the needed item */
 473         value = strtoul (s, &end, 0);
 474         /* add also the following value */
 475         if (sum) {
 476                 while (g_ascii_isspace (*s)) s++;
 477                 if (!*s)
 478                         RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 479                 value += strtoul (s, &end, 0);
 480         }
 481         if (error)
 482                 *error = MONO_PROCESS_ERROR_NONE;
 483         return value;
 484 #endif
 485 }
 486
 487 static int
 488 get_user_hz (void)
 489 {
 490         static int user_hz = 0;
 491         if (user_hz == 0) {
 492 #ifdef _SC_CLK_TCK
 493                 user_hz = sysconf (_SC_CLK_TCK);
 494 #endif
 495                 if (user_hz == 0)
 496                         user_hz = 100;
 497         }
 498         return user_hz;
 499 }
 500
 501 static gint64
 502 get_process_stat_time (int pid, int pos, int sum, MonoProcessError *error)
 503 {
 504         gint64 val = get_process_stat_item (pid, pos, sum, error);
 505 #if defined(__APPLE__)
 506         return val;
 507 #else
 508         /* return 100ns ticks */
 509         return (val * 10000000) / get_user_hz ();
 510 #endif
 511 }
 512
 513 static gint64
 514 get_pid_status_item (int pid, const char *item, MonoProcessError *error, int multiplier)
 515 {
 516 #if defined(__APPLE__)
 517         // ignore the multiplier
 518
 519         gint64 ret;
 520         task_t task;
 521         struct task_basic_info t_info;
 522         mach_msg_type_number_t th_count = TASK_BASIC_INFO_COUNT;
 523         kern_return_t mach_ret;
 524
 525         if (pid == getpid ()) {
 526                 /* task_for_pid () doesn't work on ios, even for the current process */
 527                 task = mach_task_self ();
 528         } else {
 529                 do {
 530                         mach_ret = task_for_pid (mach_task_self (), pid, &task);
 531                 } while (mach_ret == KERN_ABORTED);
 532
 533                 if (mach_ret != KERN_SUCCESS)
 534                         RET_ERROR (MONO_PROCESS_ERROR_NOT_FOUND);
 535         }
 536
 537         do {
 538                 mach_ret = task_info (task, TASK_BASIC_INFO, (task_info_t)&t_info, &th_count);
 539         } while (mach_ret == KERN_ABORTED);
 540
 541         if (mach_ret != KERN_SUCCESS) {
 542                 if (pid != getpid ())
 543                         mach_port_deallocate (mach_task_self (), task);
 544                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 545         }
 546
 547         if (strcmp (item, "VmRSS") == 0 || strcmp (item, "VmHWM") == 0 || strcmp (item, "VmData") == 0)
 548                 ret = t_info.resident_size;
 549         else if (strcmp (item, "VmSize") == 0 || strcmp (item, "VmPeak") == 0)
 550                 ret = t_info.virtual_size;
 551         else if (strcmp (item, "Threads") == 0)
 552                 ret = th_count;
 553         else
 554                 ret = 0;
 555
 556         if (pid != getpid ())
 557                 mach_port_deallocate (mach_task_self (), task);
 558
 559         return ret;
 560 #else
 561         char buf [64];
 562         char *s;
 563
 564         s = get_pid_status_item_buf (pid, item, buf, sizeof (buf), error);
 565         if (s)
 566                 return ((gint64) atol (s)) * multiplier;
 567         return 0;
 568 #endif
 569 }
 570
 571 /**
 572  * mono_process_get_data:
 573  * @pid: pid of the process
 574  * @data: description of data to return
 575  *
 576  * Return a data item of a process like user time, memory use etc,
 577  * according to the @data argumet.
 578  */
 579 gint64
 580 mono_process_get_data_with_error (gpointer pid, MonoProcessData data, MonoProcessError *error)
 581 {
 582         gint64 val;
 583         int rpid = GPOINTER_TO_INT (pid);
 584
 585         if (error)
 586                 *error = MONO_PROCESS_ERROR_OTHER;
 587
 588         switch (data) {
 589         case MONO_PROCESS_NUM_THREADS:
 590                 return get_pid_status_item (rpid, "Threads", error, 1);
 591         case MONO_PROCESS_USER_TIME:
 592                 return get_process_stat_time (rpid, 10, FALSE, error);
 593         case MONO_PROCESS_SYSTEM_TIME:
 594                 return get_process_stat_time (rpid, 11, FALSE, error);
 595         case MONO_PROCESS_TOTAL_TIME:
 596                 return get_process_stat_time (rpid, 10, TRUE, error);
 597         case MONO_PROCESS_WORKING_SET:
 598                 return get_pid_status_item (rpid, "VmRSS", error, 1024);
 599         case MONO_PROCESS_WORKING_SET_PEAK:
 600                 val = get_pid_status_item (rpid, "VmHWM", error, 1024);
 601                 if (val == 0)
 602                         val = get_pid_status_item (rpid, "VmRSS", error, 1024);
 603                 return val;
 604         case MONO_PROCESS_PRIVATE_BYTES:
 605                 return get_pid_status_item (rpid, "VmData", error, 1024);
 606         case MONO_PROCESS_VIRTUAL_BYTES:
 607                 return get_pid_status_item (rpid, "VmSize", error, 1024);
 608         case MONO_PROCESS_VIRTUAL_BYTES_PEAK:
 609                 val = get_pid_status_item (rpid, "VmPeak", error, 1024);
 610                 if (val == 0)
 611                         val = get_pid_status_item (rpid, "VmSize", error, 1024);
 612                 return val;
 613         case MONO_PROCESS_FAULTS:
 614                 return get_process_stat_item (rpid, 6, TRUE, error);
 615         case MONO_PROCESS_ELAPSED:
 616                 return get_process_stat_time (rpid, 18, FALSE, error);
 617         case MONO_PROCESS_PPID:
 618                 return get_process_stat_time (rpid, 0, FALSE, error);
 619         case MONO_PROCESS_PAGED_BYTES:
 620                 return get_pid_status_item (rpid, "VmSwap", error, 1024);
 621
 622                 /* Nothing yet */
 623         case MONO_PROCESS_END:
 624                 return 0;
 625         }
 626         return 0;
 627 }
 628
 629 gint64
 630 mono_process_get_data (gpointer pid, MonoProcessData data)
 631 {
 632         MonoProcessError error;
 633         return mono_process_get_data_with_error (pid, data, &error);
 634 }
 635
 636 #ifndef HOST_WIN32
 637 int
 638 mono_process_current_pid ()
 639 {
 640 #if defined(HAVE_UNISTD_H)
 641         return (int) getpid ();
 642 #else
 643 #error getpid
 644 #endif
 645 }
 646 #endif /* !HOST_WIN32 */
 647
 648 /**
 649  * mono_cpu_count:
 650  *
 651  * Return the number of processors on the system.
 652  */
 653 #ifndef HOST_WIN32
 654 int
 655 mono_cpu_count (void)
 656 {
 657 #ifdef PLATFORM_ANDROID
 658         /* Android tries really hard to save power by powering off CPUs on SMP phones which
 659          * means the normal way to query cpu count returns a wrong value with userspace API.
 660          * Instead we use /sys entries to query the actual hardware CPU count.
 661          */
 662         int count = 0;
 663         char buffer[8] = {'\0'};
 664         int present = open ("/sys/devices/system/cpu/present", O_RDONLY);
 665         /* Format of the /sys entry is a cpulist of indexes which in the case
 666          * of present is always of the form "0-(n-1)" when there is more than
 667          * 1 core, n being the number of CPU cores in the system. Otherwise
 668          * the value is simply 0
 669          */
 670         if (present != -1 && read (present, (char*)buffer, sizeof (buffer)) > 3)
 671                 count = strtol (((char*)buffer) + 2, NULL, 10);
 672         if (present != -1)
 673                 close (present);
 674         if (count > 0)
 675                 return count + 1;
 676 #endif
 677
 678 #if defined(HOST_ARM) || defined (HOST_ARM64)
 679
 680 /*
 681  * Recap from Alexander Köplinger <alex.koeplinger@outlook.com>:
 682  *
 683  * When we merged the change from PR #2722, we started seeing random failures on ARM in
 684  * the MonoTests.System.Threading.ThreadPoolTests.SetAndGetMaxThreads and
 685  * MonoTests.System.Threading.ManualResetEventSlimTests.Constructor_Defaults tests. Both
 686  * of those tests are dealing with Environment.ProcessorCount to verify some implementation
 687  * details.
 688  *
 689  * It turns out that on the Jetson TK1 board we use on public Jenkins and on ARM kernels
 690  * in general, the value returned by sched_getaffinity (or _SC_NPROCESSORS_ONLN) doesn't
 691  * contain CPUs/cores that are powered off for power saving reasons. This is contrary to
 692  * what happens on x86, where even cores in deep-sleep state are returned [1], [2]. This
 693  * means that we would get a processor count of 1 at one point in time and a higher value
 694  * when load increases later on as the system wakes CPUs.
 695  *
 696  * Various runtime pieces like the threadpool and also user code however relies on the
 697  * value returned by Environment.ProcessorCount e.g. for deciding how many parallel tasks
 698  * to start, thereby limiting the performance when that code thinks we only have one CPU.
 699  *
 700  * Talking to a few people, this was the reason why we changed to _SC_NPROCESSORS_CONF in
 701  * mono#1688 and why we added a special case for Android in mono@de3addc to get the "real"
 702  * number of processors in the system.
 703  *
 704  * Because of those issues Android/Dalvik also switched from _ONLN to _SC_NPROCESSORS_CONF
 705  * for the Java API Runtime.availableProcessors() too [3], citing:
 706  * > Traditionally this returned the number currently online, but many mobile devices are
 707  * able to take unused cores offline to save power, so releases newer than Android 4.2 (Jelly
 708  * Bean) return the maximum number of cores that could be made available if there were no
 709  * power or heat constraints.
 710  *
 711  * The problem with sticking to _SC_NPROCESSORS_CONF however is that it breaks down in
 712  * constrained environments like Docker or with an explicit CPU affinity set by the Linux
 713  * `taskset` command, They'd get a higher CPU count than can be used, start more threads etc.
 714  * which results in unnecessary context switches and overloaded systems. That's why we need
 715  * to respect sched_getaffinity.
 716  *
 717  * So while in an ideal world we would be able to rely on sched_getaffinity/_SC_NPROCESSORS_ONLN
 718  * to return the number of theoretically available CPUs regardless of power saving measures
 719  * everywhere, we can't do this on ARM.
 720  *
 721  * I think the pragmatic solution is the following:
 722  * * use sched_getaffinity (+ fallback to _SC_NPROCESSORS_ONLN in case of error) on x86. This
 723  * ensures we're inline with what OpenJDK [4] and CoreCLR [5] do
 724  * * use _SC_NPROCESSORS_CONF exclusively on ARM (I think we could eventually even get rid of
 725  * the PLATFORM_ANDROID special case)
 726  *
 727  * Helpful links:
 728  *
 729  * [1] https://sourceware.org/ml/libc-alpha/2013-07/msg00383.html
 730  * [2] https://lists.01.org/pipermail/powertop/2012-September/000433.html
 731  * [3] https://android.googlesource.com/platform/libcore/+/750dc634e56c58d1d04f6a138734ac2b772900b5%5E1..750dc634e56c58d1d04f6a138734ac2b772900b5/
 732  * [4] https://bugs.openjdk.java.net/browse/JDK-6515172
 733  * [5] https://github.com/dotnet/coreclr/blob/7058273693db2555f127ce16e6b0c5b40fb04867/src/pal/src/misc/sysinfo.cpp#L148
 734  */
 735
 736 #ifdef _SC_NPROCESSORS_CONF
 737         {
 738                 int count = sysconf (_SC_NPROCESSORS_CONF);
 739                 if (count > 0)
 740                         return count;
 741         }
 742 #endif
 743
 744 #else
 745
 746 #ifdef HAVE_SCHED_GETAFFINITY
 747         {
 748                 cpu_set_t set;
 749                 if (sched_getaffinity (mono_process_current_pid (), sizeof (set), &set) == 0)
 750                         return CPU_COUNT (&set);
 751         }
 752 #endif
 753 #ifdef _SC_NPROCESSORS_ONLN
 754         {
 755                 int count = sysconf (_SC_NPROCESSORS_ONLN);
 756                 if (count > 0)
 757                         return count;
 758         }
 759 #endif
 760
 761 #endif /* defined(HOST_ARM) || defined (HOST_ARM64) */
 762
 763 #ifdef USE_SYSCTL
 764         {
 765                 int count;
 766                 int mib [2];
 767                 size_t len = sizeof (int);
 768                 mib [0] = CTL_HW;
 769                 mib [1] = HW_NCPU;
 770                 if (sysctl (mib, 2, &count, &len, NULL, 0) == 0)
 771                         return count;
 772         }
 773 #endif
 774         /* FIXME: warn */
 775         return 1;
 776 }
 777 #endif /* !HOST_WIN32 */
 778
 779 static void
 780 get_cpu_times (int cpu_id, gint64 *user, gint64 *systemt, gint64 *irq, gint64 *sirq, gint64 *idle)
 781 {
 782         char buf [256];
 783         char *s;
 784         int hz = get_user_hz ();
 785         guint64 user_ticks = 0, nice_ticks = 0, system_ticks = 0, idle_ticks = 0, irq_ticks = 0, sirq_ticks = 0;
 786         FILE *f = fopen ("/proc/stat", "r");
 787         if (!f)
 788                 return;
 789         if (cpu_id < 0)
 790                 hz *= mono_cpu_count ();
 791         while ((s = fgets (buf, sizeof (buf), f))) {
 792                 char *data = NULL;
 793                 if (cpu_id < 0 && strncmp (s, "cpu", 3) == 0 && g_ascii_isspace (s [3])) {
 794                         data = s + 4;
 795                 } else if (cpu_id >= 0 && strncmp (s, "cpu", 3) == 0 && strtol (s + 3, &data, 10) == cpu_id) {
 796                         if (data == s + 3)
 797                                 continue;
 798                         data++;
 799                 } else {
 800                         continue;
 801                 }
 802
 803                 user_ticks = strtoull (data, &data, 10);
 804                 nice_ticks = strtoull (data, &data, 10);
 805                 system_ticks = strtoull (data, &data, 10);
 806                 idle_ticks = strtoull (data, &data, 10);
 807                 /* iowait_ticks = strtoull (data, &data, 10); */
 808                 irq_ticks = strtoull (data, &data, 10);
 809                 sirq_ticks = strtoull (data, &data, 10);
 810                 break;
 811         }
 812         fclose (f);
 813
 814         if (user)
 815                 *user = (user_ticks + nice_ticks) * 10000000 / hz;
 816         if (systemt)
 817                 *systemt = (system_ticks) * 10000000 / hz;
 818         if (irq)
 819                 *irq = (irq_ticks) * 10000000 / hz;
 820         if (sirq)
 821                 *sirq = (sirq_ticks) * 10000000 / hz;
 822         if (idle)
 823                 *idle = (idle_ticks) * 10000000 / hz;
 824 }
 825
 826 /**
 827  * mono_cpu_get_data:
 828  * @cpu_id: processor number or -1 to get a summary of all the processors
 829  * @data: type of data to retrieve
 830  *
 831  * Get data about a processor on the system, like time spent in user space or idle time.
 832  */
 833 gint64
 834 mono_cpu_get_data (int cpu_id, MonoCpuData data, MonoProcessError *error)
 835 {
 836         gint64 value = 0;
 837
 838         if (error)
 839                 *error = MONO_PROCESS_ERROR_NONE;
 840         switch (data) {
 841         case MONO_CPU_USER_TIME:
 842                 get_cpu_times (cpu_id, &value, NULL, NULL, NULL, NULL);
 843                 break;
 844         case MONO_CPU_PRIV_TIME:
 845                 get_cpu_times (cpu_id, NULL, &value, NULL, NULL, NULL);
 846                 break;
 847         case MONO_CPU_INTR_TIME:
 848                 get_cpu_times (cpu_id, NULL, NULL, &value, NULL, NULL);
 849                 break;
 850         case MONO_CPU_DCP_TIME:
 851                 get_cpu_times (cpu_id, NULL, NULL, NULL, &value, NULL);
 852                 break;
 853         case MONO_CPU_IDLE_TIME:
 854                 get_cpu_times (cpu_id, NULL, NULL, NULL, NULL, &value);
 855                 break;
 856
 857         case MONO_CPU_END:
 858                 /* Nothing yet */
 859                 return 0;
 860         }
 861         return value;
 862 }
 863
 864 int
 865 mono_atexit (void (*func)(void))
 866 {
 867 #ifdef PLATFORM_ANDROID
 868         /* Some versions of android libc doesn't define atexit () */
 869         return 0;
 870 #else
 871         return atexit (func);
 872 #endif
 873 }
 874
 875 /*
 876  * This function returns the cpu usage in percentage,
 877  * normalized on the number of cores.
 878  *
 879  * Warning : the percentage returned can be > 100%. This
 880  * might happens on systems like Android which, for
 881  * battery and performance reasons, shut down cores and
 882  * lie about the number of active cores.
 883  */
 884 #ifndef HOST_WIN32
 885 gint32
 886 mono_cpu_usage (MonoCpuUsageState *prev)
 887 {
 888         gint32 cpu_usage = 0;
 889         gint64 cpu_total_time;
 890         gint64 cpu_busy_time;
 891         struct rusage resource_usage;
 892         gint64 current_time;
 893         gint64 kernel_time;
 894         gint64 user_time;
 895
 896         if (getrusage (RUSAGE_SELF, &resource_usage) == -1) {
 897                 g_error ("getrusage() failed, errno is %d (%s)\n", errno, strerror (errno));
 898                 return -1;
 899         }
 900
 901         current_time = mono_100ns_ticks ();
 902         kernel_time = resource_usage.ru_stime.tv_sec * 1000 * 1000 * 10 + resource_usage.ru_stime.tv_usec * 10;
 903         user_time = resource_usage.ru_utime.tv_sec * 1000 * 1000 * 10 + resource_usage.ru_utime.tv_usec * 10;
 904
 905         cpu_busy_time = (user_time - (prev ? prev->user_time : 0)) + (kernel_time - (prev ? prev->kernel_time : 0));
 906         cpu_total_time = (current_time - (prev ? prev->current_time : 0)) * mono_cpu_count ();
 907
 908         if (prev) {
 909                 prev->kernel_time = kernel_time;
 910                 prev->user_time = user_time;
 911                 prev->current_time = current_time;
 912         }
 913
 914         if (cpu_total_time > 0 && cpu_busy_time > 0)
 915                 cpu_usage = (gint32)(cpu_busy_time * 100 / cpu_total_time);
 916
 917         return cpu_usage;
 918 }
 919 #endif /* !HOST_WIN32 */