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 #ifdef HAVE_SCHED_GETAFFINITY
  64 #  ifndef GLIBC_HAS_CPU_COUNT
  65 static int
  66 CPU_COUNT(cpu_set_t *set)
  67 {
  68         int i, count = 0;
  69
  70         for (int i = 0; i < CPU_SETSIZE; i++)
  71                 if (CPU_ISSET(i, set))
  72                         count++;
  73         return count;
  74 }
  75 #  endif
  76 #endif
  77
  78 /**
  79  * mono_process_list:
  80  * @size: a pointer to a location where the size of the returned array is stored
  81  *
  82  * Return an array of pid values for the processes currently running on the system.
  83  * The size of the array is stored in @size.
  84  */
  85 gpointer*
  86 mono_process_list (int *size)
  87 {
  88 #if USE_SYSCTL
  89         int res, i;
  90 #ifdef KERN_PROC2
  91         int mib [6];
  92         size_t data_len = sizeof (struct kinfo_proc2) * 400;
  93         struct kinfo_proc2 *processes = g_malloc (data_len);
  94 #else
  95         int mib [4];
  96         size_t data_len = sizeof (struct kinfo_proc) * 16;
  97         struct kinfo_proc *processes;
  98         int limit = 8;
  99 #endif /* KERN_PROC2 */
 100         void **buf = NULL;
 101
 102         if (size)
 103                 *size = 0;
 104
 105 #ifdef KERN_PROC2
 106         if (!processes)
 107                 return NULL;
 108
 109         mib [0] = CTL_KERN;
 110         mib [1] = KERN_PROC2;
 111         mib [2] = KERN_PROC_ALL;
 112         mib [3] = 0;
 113         mib [4] = sizeof(struct kinfo_proc2);
 114         mib [5] = 400; /* XXX */
 115
 116         res = sysctl (mib, 6, processes, &data_len, NULL, 0);
 117         if (res < 0) {
 118                 g_free (processes);
 119                 return NULL;
 120         }
 121 #else
 122         processes = NULL;
 123         while (limit) {
 124                 mib [0] = CTL_KERN;
 125                 mib [1] = KERN_PROC;
 126                 mib [2] = KERN_PROC_ALL;
 127                 mib [3] = 0;
 128
 129                 res = sysctl (mib, 4, NULL, &data_len, NULL, 0);
 130                 if (res)
 131                         return NULL;
 132                 processes = (struct kinfo_proc *) g_malloc (data_len);
 133                 res = sysctl (mib, 4, processes, &data_len, NULL, 0);
 134                 if (res < 0) {
 135                         g_free (processes);
 136                         if (errno != ENOMEM)
 137                                 return NULL;
 138                         limit --;
 139                 } else {
 140                         break;
 141                 }
 142         }
 143 #endif /* KERN_PROC2 */
 144
 145 #ifdef KERN_PROC2
 146         res = data_len/sizeof (struct kinfo_proc2);
 147 #else
 148         res = data_len/sizeof (struct kinfo_proc);
 149 #endif /* KERN_PROC2 */
 150         buf = (void **) g_realloc (buf, res * sizeof (void*));
 151         for (i = 0; i < res; ++i)
 152                 buf [i] = GINT_TO_POINTER (processes [i].kinfo_pid_member);
 153         g_free (processes);
 154         if (size)
 155                 *size = res;
 156         return buf;
 157 #elif defined(__HAIKU__)
 158         /* FIXME: Add back the code from 9185fcc305e43428d0f40f3ee37c8a405d41c9ae */
 159         g_assert_not_reached ();
 160         return NULL;
 161 #else
 162         const char *name;
 163         void **buf = NULL;
 164         int count = 0;
 165         int i = 0;
 166         GDir *dir = g_dir_open ("/proc/", 0, NULL);
 167         if (!dir) {
 168                 if (size)
 169                         *size = 0;
 170                 return NULL;
 171         }
 172         while ((name = g_dir_read_name (dir))) {
 173                 int pid;
 174                 char *nend;
 175                 pid = strtol (name, &nend, 10);
 176                 if (pid <= 0 || nend == name || *nend)
 177                         continue;
 178                 if (i >= count) {
 179                         if (!count)
 180                                 count = 16;
 181                         else
 182                                 count *= 2;
 183                         buf = (void **)g_realloc (buf, count * sizeof (void*));
 184                 }
 185                 buf [i++] = GINT_TO_POINTER (pid);
 186         }
 187         g_dir_close (dir);
 188         if (size)
 189                 *size = i;
 190         return buf;
 191 #endif
 192 }
 193
 194 static G_GNUC_UNUSED char*
 195 get_pid_status_item_buf (int pid, const char *item, char *rbuf, int blen, MonoProcessError *error)
 196 {
 197         char buf [256];
 198         char *s;
 199         FILE *f;
 200         size_t len = strlen (item);
 201
 202         g_snprintf (buf, sizeof (buf), "/proc/%d/status", pid);
 203         f = fopen (buf, "r");
 204         if (!f) {
 205                 if (error)
 206                         *error = MONO_PROCESS_ERROR_NOT_FOUND;
 207                 return NULL;
 208         }
 209         while ((s = fgets (buf, sizeof (buf), f))) {
 210                 if (*item != *buf)
 211                         continue;
 212                 if (strncmp (buf, item, len))
 213                         continue;
 214                 s = buf + len;
 215                 while (g_ascii_isspace (*s)) s++;
 216                 if (*s++ != ':')
 217                         continue;
 218                 while (g_ascii_isspace (*s)) s++;
 219                 fclose (f);
 220                 len = strlen (s);
 221                 strncpy (rbuf, s, MIN (len, blen));
 222                 rbuf [MIN (len, blen) - 1] = 0;
 223                 if (error)
 224                         *error = MONO_PROCESS_ERROR_NONE;
 225                 return rbuf;
 226         }
 227         fclose (f);
 228         if (error)
 229                 *error = MONO_PROCESS_ERROR_OTHER;
 230         return NULL;
 231 }
 232
 233 #if USE_SYSCTL
 234
 235 #ifdef KERN_PROC2
 236 #define KINFO_PROC struct kinfo_proc2
 237 #else
 238 #define KINFO_PROC struct kinfo_proc
 239 #endif
 240
 241 static gboolean
 242 sysctl_kinfo_proc (gpointer pid, KINFO_PROC* processi)
 243 {
 244         int res;
 245         size_t data_len = sizeof (KINFO_PROC);
 246
 247 #ifdef KERN_PROC2
 248         int mib [6];
 249         mib [0] = CTL_KERN;
 250         mib [1] = KERN_PROC2;
 251         mib [2] = KERN_PROC_PID;
 252         mib [3] = GPOINTER_TO_UINT (pid);
 253         mib [4] = sizeof(KINFO_PROC);
 254         mib [5] = 400; /* XXX */
 255
 256         res = sysctl (mib, 6, processi, &data_len, NULL, 0);
 257 #else
 258         int mib [4];
 259         mib [0] = CTL_KERN;
 260         mib [1] = KERN_PROC;
 261         mib [2] = KERN_PROC_PID;
 262         mib [3] = GPOINTER_TO_UINT (pid);
 263
 264         res = sysctl (mib, 4, processi, &data_len, NULL, 0);
 265 #endif /* KERN_PROC2 */
 266
 267         if (res < 0 || data_len != sizeof (KINFO_PROC))
 268                 return FALSE;
 269
 270         return TRUE;
 271 }
 272 #endif /* USE_SYSCTL */
 273
 274 /**
 275  * mono_process_get_name:
 276  * @pid: pid of the process
 277  * @buf: byte buffer where to store the name of the prcoess
 278  * @len: size of the buffer @buf
 279  *
 280  * Return the name of the process identified by @pid, storing it
 281  * inside @buf for a maximum of len bytes (including the terminating 0).
 282  */
 283 char*
 284 mono_process_get_name (gpointer pid, char *buf, int len)
 285 {
 286 #if USE_SYSCTL
 287         KINFO_PROC processi;
 288
 289         memset (buf, 0, len);
 290
 291         if (sysctl_kinfo_proc (pid, &processi))
 292                 strncpy (buf, processi.kinfo_name_member, len - 1);
 293
 294         return buf;
 295 #else
 296         char fname [128];
 297         FILE *file;
 298         char *p;
 299         size_t r;
 300         sprintf (fname, "/proc/%d/cmdline", GPOINTER_TO_INT (pid));
 301         buf [0] = 0;
 302         file = fopen (fname, "r");
 303         if (!file)
 304                 return buf;
 305         r = fread (buf, 1, len - 1, file);
 306         fclose (file);
 307         buf [r] = 0;
 308         p = strrchr (buf, '/');
 309         if (p)
 310                 return p + 1;
 311         if (r == 0) {
 312                 return get_pid_status_item_buf (GPOINTER_TO_INT (pid), "Name", buf, len, NULL);
 313         }
 314         return buf;
 315 #endif
 316 }
 317
 318 void
 319 mono_process_get_times (gpointer pid, gint64 *start_time, gint64 *user_time, gint64 *kernel_time)
 320 {
 321         if (user_time)
 322                 *user_time = mono_process_get_data (pid, MONO_PROCESS_USER_TIME);
 323
 324         if (kernel_time)
 325                 *kernel_time = mono_process_get_data (pid, MONO_PROCESS_SYSTEM_TIME);
 326
 327         if (start_time) {
 328                 *start_time = 0;
 329
 330 #if USE_SYSCTL && defined(kinfo_starttime_member)
 331                 {
 332                         KINFO_PROC processi;
 333
 334                         if (sysctl_kinfo_proc (pid, &processi)) {
 335 #if defined(__NetBSD__)
 336                                 struct timeval tv;
 337                                 tv.tv_sec = processi.kinfo_starttime_member;
 338                                 tv.tv_usec = processi.p_ustart_usec;
 339                                 *start_time = mono_100ns_datetime_from_timeval(tv);
 340 #else
 341                                 *start_time = mono_100ns_datetime_from_timeval (processi.kinfo_starttime_member);
 342 #endif
 343                         }
 344                 }
 345 #endif
 346
 347                 if (*start_time == 0) {
 348                         static guint64 boot_time = 0;
 349                         if (!boot_time)
 350                                 boot_time = mono_100ns_datetime () - mono_msec_boottime () * 10000;
 351
 352                         *start_time = boot_time + mono_process_get_data (pid, MONO_PROCESS_ELAPSED);
 353                 }
 354         }
 355 }
 356
 357 /*
 358  * /proc/pid/stat format:
 359  * pid (cmdname) S
 360  *      [0] ppid pgid sid tty_nr tty_pgrp flags min_flt cmin_flt maj_flt cmaj_flt
 361  *      [10] utime stime cutime cstime prio nice threads 0 start_time vsize
 362  *      [20] rss rsslim start_code end_code start_stack esp eip pending blocked sigign
 363  *      [30] sigcatch wchan 0 0 exit_signal cpu rt_prio policy
 364  */
 365
 366 #define RET_ERROR(err) do {     \
 367                 if (error) *error = (err);      \
 368                 return 0;                       \
 369         } while (0)
 370
 371 static gint64
 372 get_process_stat_item (int pid, int pos, int sum, MonoProcessError *error)
 373 {
 374 #if defined(__APPLE__)
 375         double process_user_time = 0, process_system_time = 0;//, process_percent = 0;
 376         task_t task;
 377         struct task_basic_info t_info;
 378         mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT, th_count;
 379         thread_array_t th_array;
 380         size_t i;
 381         kern_return_t ret;
 382
 383         if (pid == getpid ()) {
 384                 /* task_for_pid () doesn't work on ios, even for the current process */
 385                 task = mach_task_self ();
 386         } else {
 387                 do {
 388                         ret = task_for_pid (mach_task_self (), pid, &task);
 389                 } while (ret == KERN_ABORTED);
 390
 391                 if (ret != KERN_SUCCESS)
 392                         RET_ERROR (MONO_PROCESS_ERROR_NOT_FOUND);
 393         }
 394
 395         do {
 396                 ret = task_info (task, TASK_BASIC_INFO, (task_info_t)&t_info, &t_info_count);
 397         } while (ret == KERN_ABORTED);
 398
 399         if (ret != KERN_SUCCESS) {
 400                 if (pid != getpid ())
 401                         mach_port_deallocate (mach_task_self (), task);
 402                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 403         }
 404
 405         do {
 406                 ret = task_threads (task, &th_array, &th_count);
 407         } while (ret == KERN_ABORTED);
 408
 409         if (ret  != KERN_SUCCESS) {
 410                 if (pid != getpid ())
 411                         mach_port_deallocate (mach_task_self (), task);
 412                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 413         }
 414
 415         for (i = 0; i < th_count; i++) {
 416                 double thread_user_time, thread_system_time;//, thread_percent;
 417
 418                 struct thread_basic_info th_info;
 419                 mach_msg_type_number_t th_info_count = THREAD_BASIC_INFO_COUNT;
 420                 do {
 421                         ret = thread_info(th_array[i], THREAD_BASIC_INFO, (thread_info_t)&th_info, &th_info_count);
 422                 } while (ret == KERN_ABORTED);
 423
 424                 if (ret == KERN_SUCCESS) {
 425                         thread_user_time = th_info.user_time.seconds + th_info.user_time.microseconds / 1e6;
 426                         thread_system_time = th_info.system_time.seconds + th_info.system_time.microseconds / 1e6;
 427                         //thread_percent = (double)th_info.cpu_usage / TH_USAGE_SCALE;
 428
 429                         process_user_time += thread_user_time;
 430                         process_system_time += thread_system_time;
 431                         //process_percent += th_percent;
 432                 }
 433         }
 434
 435         for (i = 0; i < th_count; i++)
 436                 mach_port_deallocate(task, th_array[i]);
 437
 438         if (pid != getpid ())
 439                 mach_port_deallocate (mach_task_self (), task);
 440
 441         process_user_time += t_info.user_time.seconds + t_info.user_time.microseconds / 1e6;
 442         process_system_time += t_info.system_time.seconds + t_info.system_time.microseconds / 1e6;
 443
 444         if (pos == 10 && sum == TRUE)
 445                 return (gint64)((process_user_time + process_system_time) * 10000000);
 446         else if (pos == 10)
 447                 return (gint64)(process_user_time * 10000000);
 448         else if (pos == 11)
 449                 return (gint64)(process_system_time * 10000000);
 450
 451         return 0;
 452 #else
 453         char buf [512];
 454         char *s, *end;
 455         FILE *f;
 456         size_t len;
 457         int i;
 458         gint64 value;
 459
 460         g_snprintf (buf, sizeof (buf), "/proc/%d/stat", pid);
 461         f = fopen (buf, "r");
 462         if (!f)
 463                 RET_ERROR (MONO_PROCESS_ERROR_NOT_FOUND);
 464         len = fread (buf, 1, sizeof (buf), f);
 465         fclose (f);
 466         if (len <= 0)
 467                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 468         s = strchr (buf, ')');
 469         if (!s)
 470                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 471         s++;
 472         while (g_ascii_isspace (*s)) s++;
 473         if (!*s)
 474                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 475         /* skip the status char */
 476         while (*s && !g_ascii_isspace (*s)) s++;
 477         if (!*s)
 478                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 479         for (i = 0; i < pos; ++i) {
 480                 while (g_ascii_isspace (*s)) s++;
 481                 if (!*s)
 482                         RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 483                 while (*s && !g_ascii_isspace (*s)) s++;
 484                 if (!*s)
 485                         RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 486         }
 487         /* we are finally at the needed item */
 488         value = strtoul (s, &end, 0);
 489         /* add also the following value */
 490         if (sum) {
 491                 while (g_ascii_isspace (*s)) s++;
 492                 if (!*s)
 493                         RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 494                 value += strtoul (s, &end, 0);
 495         }
 496         if (error)
 497                 *error = MONO_PROCESS_ERROR_NONE;
 498         return value;
 499 #endif
 500 }
 501
 502 static int
 503 get_user_hz (void)
 504 {
 505         static int user_hz = 0;
 506         if (user_hz == 0) {
 507 #ifdef _SC_CLK_TCK
 508                 user_hz = sysconf (_SC_CLK_TCK);
 509 #endif
 510                 if (user_hz == 0)
 511                         user_hz = 100;
 512         }
 513         return user_hz;
 514 }
 515
 516 static gint64
 517 get_process_stat_time (int pid, int pos, int sum, MonoProcessError *error)
 518 {
 519         gint64 val = get_process_stat_item (pid, pos, sum, error);
 520 #if defined(__APPLE__)
 521         return val;
 522 #else
 523         /* return 100ns ticks */
 524         return (val * 10000000) / get_user_hz ();
 525 #endif
 526 }
 527
 528 static gint64
 529 get_pid_status_item (int pid, const char *item, MonoProcessError *error, int multiplier)
 530 {
 531 #if defined(__APPLE__)
 532         // ignore the multiplier
 533
 534         gint64 ret;
 535         task_t task;
 536         struct task_basic_info t_info;
 537         mach_msg_type_number_t th_count = TASK_BASIC_INFO_COUNT;
 538         kern_return_t mach_ret;
 539
 540         if (pid == getpid ()) {
 541                 /* task_for_pid () doesn't work on ios, even for the current process */
 542                 task = mach_task_self ();
 543         } else {
 544                 do {
 545                         mach_ret = task_for_pid (mach_task_self (), pid, &task);
 546                 } while (mach_ret == KERN_ABORTED);
 547
 548                 if (mach_ret != KERN_SUCCESS)
 549                         RET_ERROR (MONO_PROCESS_ERROR_NOT_FOUND);
 550         }
 551
 552         do {
 553                 mach_ret = task_info (task, TASK_BASIC_INFO, (task_info_t)&t_info, &th_count);
 554         } while (mach_ret == KERN_ABORTED);
 555
 556         if (mach_ret != KERN_SUCCESS) {
 557                 if (pid != getpid ())
 558                         mach_port_deallocate (mach_task_self (), task);
 559                 RET_ERROR (MONO_PROCESS_ERROR_OTHER);
 560         }
 561
 562         if (strcmp (item, "VmRSS") == 0 || strcmp (item, "VmHWM") == 0 || strcmp (item, "VmData") == 0)
 563                 ret = t_info.resident_size;
 564         else if (strcmp (item, "VmSize") == 0 || strcmp (item, "VmPeak") == 0)
 565                 ret = t_info.virtual_size;
 566         else if (strcmp (item, "Threads") == 0)
 567                 ret = th_count;
 568         else
 569                 ret = 0;
 570
 571         if (pid != getpid ())
 572                 mach_port_deallocate (mach_task_self (), task);
 573
 574         return ret;
 575 #else
 576         char buf [64];
 577         char *s;
 578
 579         s = get_pid_status_item_buf (pid, item, buf, sizeof (buf), error);
 580         if (s)
 581                 return ((gint64) atol (s)) * multiplier;
 582         return 0;
 583 #endif
 584 }
 585
 586 /**
 587  * mono_process_get_data:
 588  * @pid: pid of the process
 589  * @data: description of data to return
 590  *
 591  * Return a data item of a process like user time, memory use etc,
 592  * according to the @data argumet.
 593  */
 594 gint64
 595 mono_process_get_data_with_error (gpointer pid, MonoProcessData data, MonoProcessError *error)
 596 {
 597         gint64 val;
 598         int rpid = GPOINTER_TO_INT (pid);
 599
 600         if (error)
 601                 *error = MONO_PROCESS_ERROR_OTHER;
 602
 603         switch (data) {
 604         case MONO_PROCESS_NUM_THREADS:
 605                 return get_pid_status_item (rpid, "Threads", error, 1);
 606         case MONO_PROCESS_USER_TIME:
 607                 return get_process_stat_time (rpid, 10, FALSE, error);
 608         case MONO_PROCESS_SYSTEM_TIME:
 609                 return get_process_stat_time (rpid, 11, FALSE, error);
 610         case MONO_PROCESS_TOTAL_TIME:
 611                 return get_process_stat_time (rpid, 10, TRUE, error);
 612         case MONO_PROCESS_WORKING_SET:
 613                 return get_pid_status_item (rpid, "VmRSS", error, 1024);
 614         case MONO_PROCESS_WORKING_SET_PEAK:
 615                 val = get_pid_status_item (rpid, "VmHWM", error, 1024);
 616                 if (val == 0)
 617                         val = get_pid_status_item (rpid, "VmRSS", error, 1024);
 618                 return val;
 619         case MONO_PROCESS_PRIVATE_BYTES:
 620                 return get_pid_status_item (rpid, "VmData", error, 1024);
 621         case MONO_PROCESS_VIRTUAL_BYTES:
 622                 return get_pid_status_item (rpid, "VmSize", error, 1024);
 623         case MONO_PROCESS_VIRTUAL_BYTES_PEAK:
 624                 val = get_pid_status_item (rpid, "VmPeak", error, 1024);
 625                 if (val == 0)
 626                         val = get_pid_status_item (rpid, "VmSize", error, 1024);
 627                 return val;
 628         case MONO_PROCESS_FAULTS:
 629                 return get_process_stat_item (rpid, 6, TRUE, error);
 630         case MONO_PROCESS_ELAPSED:
 631                 return get_process_stat_time (rpid, 18, FALSE, error);
 632         case MONO_PROCESS_PPID:
 633                 return get_process_stat_time (rpid, 0, FALSE, error);
 634         case MONO_PROCESS_PAGED_BYTES:
 635                 return get_pid_status_item (rpid, "VmSwap", error, 1024);
 636
 637                 /* Nothing yet */
 638         case MONO_PROCESS_END:
 639                 return 0;
 640         }
 641         return 0;
 642 }
 643
 644 gint64
 645 mono_process_get_data (gpointer pid, MonoProcessData data)
 646 {
 647         MonoProcessError error;
 648         return mono_process_get_data_with_error (pid, data, &error);
 649 }
 650
 651 #ifndef HOST_WIN32
 652 int
 653 mono_process_current_pid ()
 654 {
 655 #if defined(HAVE_UNISTD_H)
 656         return (int) getpid ();
 657 #else
 658 #error getpid
 659 #endif
 660 }
 661 #endif /* !HOST_WIN32 */
 662
 663 /**
 664  * mono_cpu_count:
 665  *
 666  * Return the number of processors on the system.
 667  */
 668 #ifndef HOST_WIN32
 669 int
 670 mono_cpu_count (void)
 671 {
 672 #ifdef PLATFORM_ANDROID
 673         /* Android tries really hard to save power by powering off CPUs on SMP phones which
 674          * means the normal way to query cpu count returns a wrong value with userspace API.
 675          * Instead we use /sys entries to query the actual hardware CPU count.
 676          */
 677         int count = 0;
 678         char buffer[8] = {'\0'};
 679         int present = open ("/sys/devices/system/cpu/present", O_RDONLY);
 680         /* Format of the /sys entry is a cpulist of indexes which in the case
 681          * of present is always of the form "0-(n-1)" when there is more than
 682          * 1 core, n being the number of CPU cores in the system. Otherwise
 683          * the value is simply 0
 684          */
 685         if (present != -1 && read (present, (char*)buffer, sizeof (buffer)) > 3)
 686                 count = strtol (((char*)buffer) + 2, NULL, 10);
 687         if (present != -1)
 688                 close (present);
 689         if (count > 0)
 690                 return count + 1;
 691 #endif
 692
 693 #if defined(HOST_ARM) || defined (HOST_ARM64)
 694
 695 /*
 696  * Recap from Alexander Köplinger <alex.koeplinger@outlook.com>:
 697  *
 698  * When we merged the change from PR #2722, we started seeing random failures on ARM in
 699  * the MonoTests.System.Threading.ThreadPoolTests.SetAndGetMaxThreads and
 700  * MonoTests.System.Threading.ManualResetEventSlimTests.Constructor_Defaults tests. Both
 701  * of those tests are dealing with Environment.ProcessorCount to verify some implementation
 702  * details.
 703  *
 704  * It turns out that on the Jetson TK1 board we use on public Jenkins and on ARM kernels
 705  * in general, the value returned by sched_getaffinity (or _SC_NPROCESSORS_ONLN) doesn't
 706  * contain CPUs/cores that are powered off for power saving reasons. This is contrary to
 707  * what happens on x86, where even cores in deep-sleep state are returned [1], [2]. This
 708  * means that we would get a processor count of 1 at one point in time and a higher value
 709  * when load increases later on as the system wakes CPUs.
 710  *
 711  * Various runtime pieces like the threadpool and also user code however relies on the
 712  * value returned by Environment.ProcessorCount e.g. for deciding how many parallel tasks
 713  * to start, thereby limiting the performance when that code thinks we only have one CPU.
 714  *
 715  * Talking to a few people, this was the reason why we changed to _SC_NPROCESSORS_CONF in
 716  * mono#1688 and why we added a special case for Android in mono@de3addc to get the "real"
 717  * number of processors in the system.
 718  *
 719  * Because of those issues Android/Dalvik also switched from _ONLN to _SC_NPROCESSORS_CONF
 720  * for the Java API Runtime.availableProcessors() too [3], citing:
 721  * > Traditionally this returned the number currently online, but many mobile devices are
 722  * able to take unused cores offline to save power, so releases newer than Android 4.2 (Jelly
 723  * Bean) return the maximum number of cores that could be made available if there were no
 724  * power or heat constraints.
 725  *
 726  * The problem with sticking to _SC_NPROCESSORS_CONF however is that it breaks down in
 727  * constrained environments like Docker or with an explicit CPU affinity set by the Linux
 728  * `taskset` command, They'd get a higher CPU count than can be used, start more threads etc.
 729  * which results in unnecessary context switches and overloaded systems. That's why we need
 730  * to respect sched_getaffinity.
 731  *
 732  * So while in an ideal world we would be able to rely on sched_getaffinity/_SC_NPROCESSORS_ONLN
 733  * to return the number of theoretically available CPUs regardless of power saving measures
 734  * everywhere, we can't do this on ARM.
 735  *
 736  * I think the pragmatic solution is the following:
 737  * * use sched_getaffinity (+ fallback to _SC_NPROCESSORS_ONLN in case of error) on x86. This
 738  * ensures we're inline with what OpenJDK [4] and CoreCLR [5] do
 739  * * use _SC_NPROCESSORS_CONF exclusively on ARM (I think we could eventually even get rid of
 740  * the PLATFORM_ANDROID special case)
 741  *
 742  * Helpful links:
 743  *
 744  * [1] https://sourceware.org/ml/libc-alpha/2013-07/msg00383.html
 745  * [2] https://lists.01.org/pipermail/powertop/2012-September/000433.html
 746  * [3] https://android.googlesource.com/platform/libcore/+/750dc634e56c58d1d04f6a138734ac2b772900b5%5E1..750dc634e56c58d1d04f6a138734ac2b772900b5/
 747  * [4] https://bugs.openjdk.java.net/browse/JDK-6515172
 748  * [5] https://github.com/dotnet/coreclr/blob/7058273693db2555f127ce16e6b0c5b40fb04867/src/pal/src/misc/sysinfo.cpp#L148
 749  */
 750
 751 #ifdef _SC_NPROCESSORS_CONF
 752         {
 753                 int count = sysconf (_SC_NPROCESSORS_CONF);
 754                 if (count > 0)
 755                         return count;
 756         }
 757 #endif
 758
 759 #else
 760
 761 #ifdef HAVE_SCHED_GETAFFINITY
 762         {
 763                 cpu_set_t set;
 764                 if (sched_getaffinity (mono_process_current_pid (), sizeof (set), &set) == 0)
 765                         return CPU_COUNT (&set);
 766         }
 767 #endif
 768 #ifdef _SC_NPROCESSORS_ONLN
 769         {
 770                 int count = sysconf (_SC_NPROCESSORS_ONLN);
 771                 if (count > 0)
 772                         return count;
 773         }
 774 #endif
 775
 776 #endif /* defined(HOST_ARM) || defined (HOST_ARM64) */
 777
 778 #ifdef USE_SYSCTL
 779         {
 780                 int count;
 781                 int mib [2];
 782                 size_t len = sizeof (int);
 783                 mib [0] = CTL_HW;
 784                 mib [1] = HW_NCPU;
 785                 if (sysctl (mib, 2, &count, &len, NULL, 0) == 0)
 786                         return count;
 787         }
 788 #endif
 789         /* FIXME: warn */
 790         return 1;
 791 }
 792 #endif /* !HOST_WIN32 */
 793
 794 static void
 795 get_cpu_times (int cpu_id, gint64 *user, gint64 *systemt, gint64 *irq, gint64 *sirq, gint64 *idle)
 796 {
 797         char buf [256];
 798         char *s;
 799         int hz = get_user_hz ();
 800         guint64 user_ticks = 0, nice_ticks = 0, system_ticks = 0, idle_ticks = 0, irq_ticks = 0, sirq_ticks = 0;
 801         FILE *f = fopen ("/proc/stat", "r");
 802         if (!f)
 803                 return;
 804         if (cpu_id < 0)
 805                 hz *= mono_cpu_count ();
 806         while ((s = fgets (buf, sizeof (buf), f))) {
 807                 char *data = NULL;
 808                 if (cpu_id < 0 && strncmp (s, "cpu", 3) == 0 && g_ascii_isspace (s [3])) {
 809                         data = s + 4;
 810                 } else if (cpu_id >= 0 && strncmp (s, "cpu", 3) == 0 && strtol (s + 3, &data, 10) == cpu_id) {
 811                         if (data == s + 3)
 812                                 continue;
 813                         data++;
 814                 } else {
 815                         continue;
 816                 }
 817
 818                 user_ticks = strtoull (data, &data, 10);
 819                 nice_ticks = strtoull (data, &data, 10);
 820                 system_ticks = strtoull (data, &data, 10);
 821                 idle_ticks = strtoull (data, &data, 10);
 822                 /* iowait_ticks = strtoull (data, &data, 10); */
 823                 irq_ticks = strtoull (data, &data, 10);
 824                 sirq_ticks = strtoull (data, &data, 10);
 825                 break;
 826         }
 827         fclose (f);
 828
 829         if (user)
 830                 *user = (user_ticks + nice_ticks) * 10000000 / hz;
 831         if (systemt)
 832                 *systemt = (system_ticks) * 10000000 / hz;
 833         if (irq)
 834                 *irq = (irq_ticks) * 10000000 / hz;
 835         if (sirq)
 836                 *sirq = (sirq_ticks) * 10000000 / hz;
 837         if (idle)
 838                 *idle = (idle_ticks) * 10000000 / hz;
 839 }
 840
 841 /**
 842  * mono_cpu_get_data:
 843  * @cpu_id: processor number or -1 to get a summary of all the processors
 844  * @data: type of data to retrieve
 845  *
 846  * Get data about a processor on the system, like time spent in user space or idle time.
 847  */
 848 gint64
 849 mono_cpu_get_data (int cpu_id, MonoCpuData data, MonoProcessError *error)
 850 {
 851         gint64 value = 0;
 852
 853         if (error)
 854                 *error = MONO_PROCESS_ERROR_NONE;
 855         switch (data) {
 856         case MONO_CPU_USER_TIME:
 857                 get_cpu_times (cpu_id, &value, NULL, NULL, NULL, NULL);
 858                 break;
 859         case MONO_CPU_PRIV_TIME:
 860                 get_cpu_times (cpu_id, NULL, &value, NULL, NULL, NULL);
 861                 break;
 862         case MONO_CPU_INTR_TIME:
 863                 get_cpu_times (cpu_id, NULL, NULL, &value, NULL, NULL);
 864                 break;
 865         case MONO_CPU_DCP_TIME:
 866                 get_cpu_times (cpu_id, NULL, NULL, NULL, &value, NULL);
 867                 break;
 868         case MONO_CPU_IDLE_TIME:
 869                 get_cpu_times (cpu_id, NULL, NULL, NULL, NULL, &value);
 870                 break;
 871
 872         case MONO_CPU_END:
 873                 /* Nothing yet */
 874                 return 0;
 875         }
 876         return value;
 877 }
 878
 879 int
 880 mono_atexit (void (*func)(void))
 881 {
 882 #ifdef PLATFORM_ANDROID
 883         /* Some versions of android libc doesn't define atexit () */
 884         return 0;
 885 #else
 886         return atexit (func);
 887 #endif
 888 }
 889
 890 /*
 891  * This function returns the cpu usage in percentage,
 892  * normalized on the number of cores.
 893  *
 894  * Warning : the percentage returned can be > 100%. This
 895  * might happens on systems like Android which, for
 896  * battery and performance reasons, shut down cores and
 897  * lie about the number of active cores.
 898  */
 899 #ifndef HOST_WIN32
 900 gint32
 901 mono_cpu_usage (MonoCpuUsageState *prev)
 902 {
 903         gint32 cpu_usage = 0;
 904         gint64 cpu_total_time;
 905         gint64 cpu_busy_time;
 906         struct rusage resource_usage;
 907         gint64 current_time;
 908         gint64 kernel_time;
 909         gint64 user_time;
 910
 911         if (getrusage (RUSAGE_SELF, &resource_usage) == -1) {
 912                 g_error ("getrusage() failed, errno is %d (%s)\n", errno, strerror (errno));
 913                 return -1;
 914         }
 915
 916         current_time = mono_100ns_ticks ();
 917         kernel_time = resource_usage.ru_stime.tv_sec * 1000 * 1000 * 10 + resource_usage.ru_stime.tv_usec * 10;
 918         user_time = resource_usage.ru_utime.tv_sec * 1000 * 1000 * 10 + resource_usage.ru_utime.tv_usec * 10;
 919
 920         cpu_busy_time = (user_time - (prev ? prev->user_time : 0)) + (kernel_time - (prev ? prev->kernel_time : 0));
 921         cpu_total_time = (current_time - (prev ? prev->current_time : 0)) * mono_cpu_count ();
 922
 923         if (prev) {
 924                 prev->kernel_time = kernel_time;
 925                 prev->user_time = user_time;
 926                 prev->current_time = current_time;
 927         }
 928
 929         if (cpu_total_time > 0 && cpu_busy_time > 0)
 930                 cpu_usage = (gint32)(cpu_busy_time * 100 / cpu_total_time);
 931
 932         return cpu_usage;
 933 }
 934 #endif /* !HOST_WIN32 */