1 /*
2  * z_Linux_util.cpp -- platform specific routines.
3  */
4 
5 //===----------------------------------------------------------------------===//
6 //
7 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
8 // See https://llvm.org/LICENSE.txt for license information.
9 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "kmp.h"
14 #include "kmp_affinity.h"
15 #include "kmp_i18n.h"
16 #include "kmp_io.h"
17 #include "kmp_itt.h"
18 #include "kmp_lock.h"
19 #include "kmp_stats.h"
20 #include "kmp_str.h"
21 #include "kmp_wait_release.h"
22 #include "kmp_wrapper_getpid.h"
23 
24 #if !KMP_OS_DRAGONFLY && !KMP_OS_FREEBSD && !KMP_OS_NETBSD && !KMP_OS_OPENBSD
25 #include <alloca.h>
26 #endif
27 #include <math.h> // HUGE_VAL.
28 #include <sys/resource.h>
29 #include <sys/syscall.h>
30 #include <sys/time.h>
31 #include <sys/times.h>
32 #include <unistd.h>
33 
34 #if KMP_OS_LINUX
35 #include <sys/sysinfo.h>
36 #if KMP_USE_FUTEX
37 // We should really include <futex.h>, but that causes compatibility problems on
38 // different Linux* OS distributions that either require that you include (or
39 // break when you try to include) <pci/types.h>. Since all we need is the two
40 // macros below (which are part of the kernel ABI, so can't change) we just
41 // define the constants here and don't include <futex.h>
42 #ifndef FUTEX_WAIT
43 #define FUTEX_WAIT 0
44 #endif
45 #ifndef FUTEX_WAKE
46 #define FUTEX_WAKE 1
47 #endif
48 #endif
49 #elif KMP_OS_DARWIN
50 #include <mach/mach.h>
51 #include <sys/sysctl.h>
52 #elif KMP_OS_DRAGONFLY || KMP_OS_FREEBSD
53 #include <sys/types.h>
54 #include <sys/sysctl.h>
55 #include <sys/user.h>
56 #include <pthread_np.h>
57 #elif KMP_OS_NETBSD || KMP_OS_OPENBSD
58 #include <sys/types.h>
59 #include <sys/sysctl.h>
60 #endif
61 
62 #include <ctype.h>
63 #include <dirent.h>
64 #include <fcntl.h>
65 
66 #include "tsan_annotations.h"
67 
68 struct kmp_sys_timer {
69   struct timespec start;
70 };
71 
72 // Convert timespec to nanoseconds.
73 #define TS2NS(timespec) (((timespec).tv_sec * 1e9) + (timespec).tv_nsec)
74 
75 static struct kmp_sys_timer __kmp_sys_timer_data;
76 
77 #if KMP_HANDLE_SIGNALS
78 typedef void (*sig_func_t)(int);
79 STATIC_EFI2_WORKAROUND struct sigaction __kmp_sighldrs[NSIG];
80 static sigset_t __kmp_sigset;
81 #endif
82 
83 static int __kmp_init_runtime = FALSE;
84 
85 static int __kmp_fork_count = 0;
86 
87 static pthread_condattr_t __kmp_suspend_cond_attr;
88 static pthread_mutexattr_t __kmp_suspend_mutex_attr;
89 
90 static kmp_cond_align_t __kmp_wait_cv;
91 static kmp_mutex_align_t __kmp_wait_mx;
92 
93 kmp_uint64 __kmp_ticks_per_msec = 1000000;
94 
95 #ifdef DEBUG_SUSPEND
96 static void __kmp_print_cond(char *buffer, kmp_cond_align_t *cond) {
97   KMP_SNPRINTF(buffer, 128, "(cond (lock (%ld, %d)), (descr (%p)))",
98                cond->c_cond.__c_lock.__status, cond->c_cond.__c_lock.__spinlock,
99                cond->c_cond.__c_waiting);
100 }
101 #endif
102 
103 #if ((KMP_OS_LINUX || KMP_OS_FREEBSD) && KMP_AFFINITY_SUPPORTED)
104 
105 /* Affinity support */
106 
107 void __kmp_affinity_bind_thread(int which) {
108   KMP_ASSERT2(KMP_AFFINITY_CAPABLE(),
109               "Illegal set affinity operation when not capable");
110 
111   kmp_affin_mask_t *mask;
112   KMP_CPU_ALLOC_ON_STACK(mask);
113   KMP_CPU_ZERO(mask);
114   KMP_CPU_SET(which, mask);
115   __kmp_set_system_affinity(mask, TRUE);
116   KMP_CPU_FREE_FROM_STACK(mask);
117 }
118 
119 /* Determine if we can access affinity functionality on this version of
120  * Linux* OS by checking __NR_sched_{get,set}affinity system calls, and set
121  * __kmp_affin_mask_size to the appropriate value (0 means not capable). */
122 void __kmp_affinity_determine_capable(const char *env_var) {
123 // Check and see if the OS supports thread affinity.
124 
125 #if KMP_OS_LINUX
126 #define KMP_CPU_SET_SIZE_LIMIT (1024 * 1024)
127 #elif KMP_OS_FREEBSD
128 #define KMP_CPU_SET_SIZE_LIMIT (sizeof(cpuset_t))
129 #endif
130 
131 
132 #if KMP_OS_LINUX
133   // If Linux* OS:
134   // If the syscall fails or returns a suggestion for the size,
135   // then we don't have to search for an appropriate size.
136   int gCode;
137   int sCode;
138   unsigned char *buf;
139   buf = (unsigned char *)KMP_INTERNAL_MALLOC(KMP_CPU_SET_SIZE_LIMIT);
140   gCode = syscall(__NR_sched_getaffinity, 0, KMP_CPU_SET_SIZE_LIMIT, buf);
141   KA_TRACE(30, ("__kmp_affinity_determine_capable: "
142                 "initial getaffinity call returned %d errno = %d\n",
143                 gCode, errno));
144 
145   // if ((gCode < 0) && (errno == ENOSYS))
146   if (gCode < 0) {
147     // System call not supported
148     if (__kmp_affinity_verbose ||
149         (__kmp_affinity_warnings && (__kmp_affinity_type != affinity_none) &&
150          (__kmp_affinity_type != affinity_default) &&
151          (__kmp_affinity_type != affinity_disabled))) {
152       int error = errno;
153       kmp_msg_t err_code = KMP_ERR(error);
154       __kmp_msg(kmp_ms_warning, KMP_MSG(GetAffSysCallNotSupported, env_var),
155                 err_code, __kmp_msg_null);
156       if (__kmp_generate_warnings == kmp_warnings_off) {
157         __kmp_str_free(&err_code.str);
158       }
159     }
160     KMP_AFFINITY_DISABLE();
161     KMP_INTERNAL_FREE(buf);
162     return;
163   }
164   if (gCode > 0) { // Linux* OS only
165     // The optimal situation: the OS returns the size of the buffer it expects.
166     //
167     // A verification of correct behavior is that setaffinity on a NULL
168     // buffer with the same size fails with errno set to EFAULT.
169     sCode = syscall(__NR_sched_setaffinity, 0, gCode, NULL);
170     KA_TRACE(30, ("__kmp_affinity_determine_capable: "
171                   "setaffinity for mask size %d returned %d errno = %d\n",
172                   gCode, sCode, errno));
173     if (sCode < 0) {
174       if (errno == ENOSYS) {
175         if (__kmp_affinity_verbose ||
176             (__kmp_affinity_warnings &&
177              (__kmp_affinity_type != affinity_none) &&
178              (__kmp_affinity_type != affinity_default) &&
179              (__kmp_affinity_type != affinity_disabled))) {
180           int error = errno;
181           kmp_msg_t err_code = KMP_ERR(error);
182           __kmp_msg(kmp_ms_warning, KMP_MSG(SetAffSysCallNotSupported, env_var),
183                     err_code, __kmp_msg_null);
184           if (__kmp_generate_warnings == kmp_warnings_off) {
185             __kmp_str_free(&err_code.str);
186           }
187         }
188         KMP_AFFINITY_DISABLE();
189         KMP_INTERNAL_FREE(buf);
190       }
191       if (errno == EFAULT) {
192         KMP_AFFINITY_ENABLE(gCode);
193         KA_TRACE(10, ("__kmp_affinity_determine_capable: "
194                       "affinity supported (mask size %d)\n",
195                       (int)__kmp_affin_mask_size));
196         KMP_INTERNAL_FREE(buf);
197         return;
198       }
199     }
200   }
201 
202   // Call the getaffinity system call repeatedly with increasing set sizes
203   // until we succeed, or reach an upper bound on the search.
204   KA_TRACE(30, ("__kmp_affinity_determine_capable: "
205                 "searching for proper set size\n"));
206   int size;
207   for (size = 1; size <= KMP_CPU_SET_SIZE_LIMIT; size *= 2) {
208     gCode = syscall(__NR_sched_getaffinity, 0, size, buf);
209     KA_TRACE(30, ("__kmp_affinity_determine_capable: "
210                   "getaffinity for mask size %d returned %d errno = %d\n",
211                   size, gCode, errno));
212 
213     if (gCode < 0) {
214       if (errno == ENOSYS) {
215         // We shouldn't get here
216         KA_TRACE(30, ("__kmp_affinity_determine_capable: "
217                       "inconsistent OS call behavior: errno == ENOSYS for mask "
218                       "size %d\n",
219                       size));
220         if (__kmp_affinity_verbose ||
221             (__kmp_affinity_warnings &&
222              (__kmp_affinity_type != affinity_none) &&
223              (__kmp_affinity_type != affinity_default) &&
224              (__kmp_affinity_type != affinity_disabled))) {
225           int error = errno;
226           kmp_msg_t err_code = KMP_ERR(error);
227           __kmp_msg(kmp_ms_warning, KMP_MSG(GetAffSysCallNotSupported, env_var),
228                     err_code, __kmp_msg_null);
229           if (__kmp_generate_warnings == kmp_warnings_off) {
230             __kmp_str_free(&err_code.str);
231           }
232         }
233         KMP_AFFINITY_DISABLE();
234         KMP_INTERNAL_FREE(buf);
235         return;
236       }
237       continue;
238     }
239 
240     sCode = syscall(__NR_sched_setaffinity, 0, gCode, NULL);
241     KA_TRACE(30, ("__kmp_affinity_determine_capable: "
242                   "setaffinity for mask size %d returned %d errno = %d\n",
243                   gCode, sCode, errno));
244     if (sCode < 0) {
245       if (errno == ENOSYS) { // Linux* OS only
246         // We shouldn't get here
247         KA_TRACE(30, ("__kmp_affinity_determine_capable: "
248                       "inconsistent OS call behavior: errno == ENOSYS for mask "
249                       "size %d\n",
250                       size));
251         if (__kmp_affinity_verbose ||
252             (__kmp_affinity_warnings &&
253              (__kmp_affinity_type != affinity_none) &&
254              (__kmp_affinity_type != affinity_default) &&
255              (__kmp_affinity_type != affinity_disabled))) {
256           int error = errno;
257           kmp_msg_t err_code = KMP_ERR(error);
258           __kmp_msg(kmp_ms_warning, KMP_MSG(SetAffSysCallNotSupported, env_var),
259                     err_code, __kmp_msg_null);
260           if (__kmp_generate_warnings == kmp_warnings_off) {
261             __kmp_str_free(&err_code.str);
262           }
263         }
264         KMP_AFFINITY_DISABLE();
265         KMP_INTERNAL_FREE(buf);
266         return;
267       }
268       if (errno == EFAULT) {
269         KMP_AFFINITY_ENABLE(gCode);
270         KA_TRACE(10, ("__kmp_affinity_determine_capable: "
271                       "affinity supported (mask size %d)\n",
272                       (int)__kmp_affin_mask_size));
273         KMP_INTERNAL_FREE(buf);
274         return;
275       }
276     }
277   }
278 #elif KMP_OS_FREEBSD
279   int gCode;
280   unsigned char *buf;
281   buf = (unsigned char *)KMP_INTERNAL_MALLOC(KMP_CPU_SET_SIZE_LIMIT);
282   gCode = pthread_getaffinity_np(pthread_self(), KMP_CPU_SET_SIZE_LIMIT, reinterpret_cast<cpuset_t *>(buf));
283   KA_TRACE(30, ("__kmp_affinity_determine_capable: "
284                 "initial getaffinity call returned %d errno = %d\n",
285                 gCode, errno));
286   if (gCode == 0) {
287     KMP_AFFINITY_ENABLE(KMP_CPU_SET_SIZE_LIMIT);
288     KA_TRACE(10, ("__kmp_affinity_determine_capable: "
289                   "affinity supported (mask size %d)\n",
290 		  (int)__kmp_affin_mask_size));
291     KMP_INTERNAL_FREE(buf);
292     return;
293   }
294 #endif
295   // save uncaught error code
296   // int error = errno;
297   KMP_INTERNAL_FREE(buf);
298   // restore uncaught error code, will be printed at the next KMP_WARNING below
299   // errno = error;
300 
301   // Affinity is not supported
302   KMP_AFFINITY_DISABLE();
303   KA_TRACE(10, ("__kmp_affinity_determine_capable: "
304                 "cannot determine mask size - affinity not supported\n"));
305   if (__kmp_affinity_verbose ||
306       (__kmp_affinity_warnings && (__kmp_affinity_type != affinity_none) &&
307        (__kmp_affinity_type != affinity_default) &&
308        (__kmp_affinity_type != affinity_disabled))) {
309     KMP_WARNING(AffCantGetMaskSize, env_var);
310   }
311 }
312 
313 #endif // KMP_OS_LINUX && KMP_AFFINITY_SUPPORTED
314 
315 #if KMP_USE_FUTEX
316 
317 int __kmp_futex_determine_capable() {
318   int loc = 0;
319   int rc = syscall(__NR_futex, &loc, FUTEX_WAKE, 1, NULL, NULL, 0);
320   int retval = (rc == 0) || (errno != ENOSYS);
321 
322   KA_TRACE(10,
323            ("__kmp_futex_determine_capable: rc = %d errno = %d\n", rc, errno));
324   KA_TRACE(10, ("__kmp_futex_determine_capable: futex syscall%s supported\n",
325                 retval ? "" : " not"));
326 
327   return retval;
328 }
329 
330 #endif // KMP_USE_FUTEX
331 
332 #if (KMP_ARCH_X86 || KMP_ARCH_X86_64) && (!KMP_ASM_INTRINS)
333 /* Only 32-bit "add-exchange" instruction on IA-32 architecture causes us to
334    use compare_and_store for these routines */
335 
336 kmp_int8 __kmp_test_then_or8(volatile kmp_int8 *p, kmp_int8 d) {
337   kmp_int8 old_value, new_value;
338 
339   old_value = TCR_1(*p);
340   new_value = old_value | d;
341 
342   while (!KMP_COMPARE_AND_STORE_REL8(p, old_value, new_value)) {
343     KMP_CPU_PAUSE();
344     old_value = TCR_1(*p);
345     new_value = old_value | d;
346   }
347   return old_value;
348 }
349 
350 kmp_int8 __kmp_test_then_and8(volatile kmp_int8 *p, kmp_int8 d) {
351   kmp_int8 old_value, new_value;
352 
353   old_value = TCR_1(*p);
354   new_value = old_value & d;
355 
356   while (!KMP_COMPARE_AND_STORE_REL8(p, old_value, new_value)) {
357     KMP_CPU_PAUSE();
358     old_value = TCR_1(*p);
359     new_value = old_value & d;
360   }
361   return old_value;
362 }
363 
364 kmp_uint32 __kmp_test_then_or32(volatile kmp_uint32 *p, kmp_uint32 d) {
365   kmp_uint32 old_value, new_value;
366 
367   old_value = TCR_4(*p);
368   new_value = old_value | d;
369 
370   while (!KMP_COMPARE_AND_STORE_REL32(p, old_value, new_value)) {
371     KMP_CPU_PAUSE();
372     old_value = TCR_4(*p);
373     new_value = old_value | d;
374   }
375   return old_value;
376 }
377 
378 kmp_uint32 __kmp_test_then_and32(volatile kmp_uint32 *p, kmp_uint32 d) {
379   kmp_uint32 old_value, new_value;
380 
381   old_value = TCR_4(*p);
382   new_value = old_value & d;
383 
384   while (!KMP_COMPARE_AND_STORE_REL32(p, old_value, new_value)) {
385     KMP_CPU_PAUSE();
386     old_value = TCR_4(*p);
387     new_value = old_value & d;
388   }
389   return old_value;
390 }
391 
392 #if KMP_ARCH_X86
393 kmp_int8 __kmp_test_then_add8(volatile kmp_int8 *p, kmp_int8 d) {
394   kmp_int8 old_value, new_value;
395 
396   old_value = TCR_1(*p);
397   new_value = old_value + d;
398 
399   while (!KMP_COMPARE_AND_STORE_REL8(p, old_value, new_value)) {
400     KMP_CPU_PAUSE();
401     old_value = TCR_1(*p);
402     new_value = old_value + d;
403   }
404   return old_value;
405 }
406 
407 kmp_int64 __kmp_test_then_add64(volatile kmp_int64 *p, kmp_int64 d) {
408   kmp_int64 old_value, new_value;
409 
410   old_value = TCR_8(*p);
411   new_value = old_value + d;
412 
413   while (!KMP_COMPARE_AND_STORE_REL64(p, old_value, new_value)) {
414     KMP_CPU_PAUSE();
415     old_value = TCR_8(*p);
416     new_value = old_value + d;
417   }
418   return old_value;
419 }
420 #endif /* KMP_ARCH_X86 */
421 
422 kmp_uint64 __kmp_test_then_or64(volatile kmp_uint64 *p, kmp_uint64 d) {
423   kmp_uint64 old_value, new_value;
424 
425   old_value = TCR_8(*p);
426   new_value = old_value | d;
427   while (!KMP_COMPARE_AND_STORE_REL64(p, old_value, new_value)) {
428     KMP_CPU_PAUSE();
429     old_value = TCR_8(*p);
430     new_value = old_value | d;
431   }
432   return old_value;
433 }
434 
435 kmp_uint64 __kmp_test_then_and64(volatile kmp_uint64 *p, kmp_uint64 d) {
436   kmp_uint64 old_value, new_value;
437 
438   old_value = TCR_8(*p);
439   new_value = old_value & d;
440   while (!KMP_COMPARE_AND_STORE_REL64(p, old_value, new_value)) {
441     KMP_CPU_PAUSE();
442     old_value = TCR_8(*p);
443     new_value = old_value & d;
444   }
445   return old_value;
446 }
447 
448 #endif /* (KMP_ARCH_X86 || KMP_ARCH_X86_64) && (! KMP_ASM_INTRINS) */
449 
450 void __kmp_terminate_thread(int gtid) {
451   int status;
452   kmp_info_t *th = __kmp_threads[gtid];
453 
454   if (!th)
455     return;
456 
457 #ifdef KMP_CANCEL_THREADS
458   KA_TRACE(10, ("__kmp_terminate_thread: kill (%d)\n", gtid));
459   status = pthread_cancel(th->th.th_info.ds.ds_thread);
460   if (status != 0 && status != ESRCH) {
461     __kmp_fatal(KMP_MSG(CantTerminateWorkerThread), KMP_ERR(status),
462                 __kmp_msg_null);
463   }
464 #endif
465   KMP_YIELD(TRUE);
466 } //
467 
468 /* Set thread stack info according to values returned by pthread_getattr_np().
469    If values are unreasonable, assume call failed and use incremental stack
470    refinement method instead. Returns TRUE if the stack parameters could be
471    determined exactly, FALSE if incremental refinement is necessary. */
472 static kmp_int32 __kmp_set_stack_info(int gtid, kmp_info_t *th) {
473   int stack_data;
474 #if KMP_OS_LINUX || KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD ||     \
475         KMP_OS_HURD
476   pthread_attr_t attr;
477   int status;
478   size_t size = 0;
479   void *addr = 0;
480 
481   /* Always do incremental stack refinement for ubermaster threads since the
482      initial thread stack range can be reduced by sibling thread creation so
483      pthread_attr_getstack may cause thread gtid aliasing */
484   if (!KMP_UBER_GTID(gtid)) {
485 
486     /* Fetch the real thread attributes */
487     status = pthread_attr_init(&attr);
488     KMP_CHECK_SYSFAIL("pthread_attr_init", status);
489 #if KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD
490     status = pthread_attr_get_np(pthread_self(), &attr);
491     KMP_CHECK_SYSFAIL("pthread_attr_get_np", status);
492 #else
493     status = pthread_getattr_np(pthread_self(), &attr);
494     KMP_CHECK_SYSFAIL("pthread_getattr_np", status);
495 #endif
496     status = pthread_attr_getstack(&attr, &addr, &size);
497     KMP_CHECK_SYSFAIL("pthread_attr_getstack", status);
498     KA_TRACE(60,
499              ("__kmp_set_stack_info: T#%d pthread_attr_getstack returned size:"
500               " %lu, low addr: %p\n",
501               gtid, size, addr));
502     status = pthread_attr_destroy(&attr);
503     KMP_CHECK_SYSFAIL("pthread_attr_destroy", status);
504   }
505 
506   if (size != 0 && addr != 0) { // was stack parameter determination successful?
507     /* Store the correct base and size */
508     TCW_PTR(th->th.th_info.ds.ds_stackbase, (((char *)addr) + size));
509     TCW_PTR(th->th.th_info.ds.ds_stacksize, size);
510     TCW_4(th->th.th_info.ds.ds_stackgrow, FALSE);
511     return TRUE;
512   }
513 #endif /* KMP_OS_LINUX || KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD ||
514               KMP_OS_HURD */
515   /* Use incremental refinement starting from initial conservative estimate */
516   TCW_PTR(th->th.th_info.ds.ds_stacksize, 0);
517   TCW_PTR(th->th.th_info.ds.ds_stackbase, &stack_data);
518   TCW_4(th->th.th_info.ds.ds_stackgrow, TRUE);
519   return FALSE;
520 }
521 
522 static void *__kmp_launch_worker(void *thr) {
523   int status, old_type, old_state;
524 #ifdef KMP_BLOCK_SIGNALS
525   sigset_t new_set, old_set;
526 #endif /* KMP_BLOCK_SIGNALS */
527   void *exit_val;
528 #if KMP_OS_LINUX || KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD ||     \
529         KMP_OS_OPENBSD || KMP_OS_HURD
530   void *volatile padding = 0;
531 #endif
532   int gtid;
533 
534   gtid = ((kmp_info_t *)thr)->th.th_info.ds.ds_gtid;
535   __kmp_gtid_set_specific(gtid);
536 #ifdef KMP_TDATA_GTID
537   __kmp_gtid = gtid;
538 #endif
539 #if KMP_STATS_ENABLED
540   // set thread local index to point to thread-specific stats
541   __kmp_stats_thread_ptr = ((kmp_info_t *)thr)->th.th_stats;
542   __kmp_stats_thread_ptr->startLife();
543   KMP_SET_THREAD_STATE(IDLE);
544   KMP_INIT_PARTITIONED_TIMERS(OMP_idle);
545 #endif
546 
547 #if USE_ITT_BUILD
548   __kmp_itt_thread_name(gtid);
549 #endif /* USE_ITT_BUILD */
550 
551 #if KMP_AFFINITY_SUPPORTED
552   __kmp_affinity_set_init_mask(gtid, FALSE);
553 #endif
554 
555 #ifdef KMP_CANCEL_THREADS
556   status = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old_type);
557   KMP_CHECK_SYSFAIL("pthread_setcanceltype", status);
558   // josh todo: isn't PTHREAD_CANCEL_ENABLE default for newly-created threads?
559   status = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_state);
560   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
561 #endif
562 
563 #if KMP_ARCH_X86 || KMP_ARCH_X86_64
564   // Set FP control regs to be a copy of the parallel initialization thread's.
565   __kmp_clear_x87_fpu_status_word();
566   __kmp_load_x87_fpu_control_word(&__kmp_init_x87_fpu_control_word);
567   __kmp_load_mxcsr(&__kmp_init_mxcsr);
568 #endif /* KMP_ARCH_X86 || KMP_ARCH_X86_64 */
569 
570 #ifdef KMP_BLOCK_SIGNALS
571   status = sigfillset(&new_set);
572   KMP_CHECK_SYSFAIL_ERRNO("sigfillset", status);
573   status = pthread_sigmask(SIG_BLOCK, &new_set, &old_set);
574   KMP_CHECK_SYSFAIL("pthread_sigmask", status);
575 #endif /* KMP_BLOCK_SIGNALS */
576 
577 #if KMP_OS_LINUX || KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD ||     \
578         KMP_OS_OPENBSD
579   if (__kmp_stkoffset > 0 && gtid > 0) {
580     padding = KMP_ALLOCA(gtid * __kmp_stkoffset);
581   }
582 #endif
583 
584   KMP_MB();
585   __kmp_set_stack_info(gtid, (kmp_info_t *)thr);
586 
587   __kmp_check_stack_overlap((kmp_info_t *)thr);
588 
589   exit_val = __kmp_launch_thread((kmp_info_t *)thr);
590 
591 #ifdef KMP_BLOCK_SIGNALS
592   status = pthread_sigmask(SIG_SETMASK, &old_set, NULL);
593   KMP_CHECK_SYSFAIL("pthread_sigmask", status);
594 #endif /* KMP_BLOCK_SIGNALS */
595 
596   return exit_val;
597 }
598 
599 #if KMP_USE_MONITOR
600 /* The monitor thread controls all of the threads in the complex */
601 
602 static void *__kmp_launch_monitor(void *thr) {
603   int status, old_type, old_state;
604 #ifdef KMP_BLOCK_SIGNALS
605   sigset_t new_set;
606 #endif /* KMP_BLOCK_SIGNALS */
607   struct timespec interval;
608 
609   KMP_MB(); /* Flush all pending memory write invalidates.  */
610 
611   KA_TRACE(10, ("__kmp_launch_monitor: #1 launched\n"));
612 
613   /* register us as the monitor thread */
614   __kmp_gtid_set_specific(KMP_GTID_MONITOR);
615 #ifdef KMP_TDATA_GTID
616   __kmp_gtid = KMP_GTID_MONITOR;
617 #endif
618 
619   KMP_MB();
620 
621 #if USE_ITT_BUILD
622   // Instruct Intel(R) Threading Tools to ignore monitor thread.
623   __kmp_itt_thread_ignore();
624 #endif /* USE_ITT_BUILD */
625 
626   __kmp_set_stack_info(((kmp_info_t *)thr)->th.th_info.ds.ds_gtid,
627                        (kmp_info_t *)thr);
628 
629   __kmp_check_stack_overlap((kmp_info_t *)thr);
630 
631 #ifdef KMP_CANCEL_THREADS
632   status = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old_type);
633   KMP_CHECK_SYSFAIL("pthread_setcanceltype", status);
634   // josh todo: isn't PTHREAD_CANCEL_ENABLE default for newly-created threads?
635   status = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_state);
636   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
637 #endif
638 
639 #if KMP_REAL_TIME_FIX
640   // This is a potential fix which allows application with real-time scheduling
641   // policy work. However, decision about the fix is not made yet, so it is
642   // disabled by default.
643   { // Are program started with real-time scheduling policy?
644     int sched = sched_getscheduler(0);
645     if (sched == SCHED_FIFO || sched == SCHED_RR) {
646       // Yes, we are a part of real-time application. Try to increase the
647       // priority of the monitor.
648       struct sched_param param;
649       int max_priority = sched_get_priority_max(sched);
650       int rc;
651       KMP_WARNING(RealTimeSchedNotSupported);
652       sched_getparam(0, &param);
653       if (param.sched_priority < max_priority) {
654         param.sched_priority += 1;
655         rc = sched_setscheduler(0, sched, &param);
656         if (rc != 0) {
657           int error = errno;
658           kmp_msg_t err_code = KMP_ERR(error);
659           __kmp_msg(kmp_ms_warning, KMP_MSG(CantChangeMonitorPriority),
660                     err_code, KMP_MSG(MonitorWillStarve), __kmp_msg_null);
661           if (__kmp_generate_warnings == kmp_warnings_off) {
662             __kmp_str_free(&err_code.str);
663           }
664         }
665       } else {
666         // We cannot abort here, because number of CPUs may be enough for all
667         // the threads, including the monitor thread, so application could
668         // potentially work...
669         __kmp_msg(kmp_ms_warning, KMP_MSG(RunningAtMaxPriority),
670                   KMP_MSG(MonitorWillStarve), KMP_HNT(RunningAtMaxPriority),
671                   __kmp_msg_null);
672       }
673     }
674     // AC: free thread that waits for monitor started
675     TCW_4(__kmp_global.g.g_time.dt.t_value, 0);
676   }
677 #endif // KMP_REAL_TIME_FIX
678 
679   KMP_MB(); /* Flush all pending memory write invalidates.  */
680 
681   if (__kmp_monitor_wakeups == 1) {
682     interval.tv_sec = 1;
683     interval.tv_nsec = 0;
684   } else {
685     interval.tv_sec = 0;
686     interval.tv_nsec = (KMP_NSEC_PER_SEC / __kmp_monitor_wakeups);
687   }
688 
689   KA_TRACE(10, ("__kmp_launch_monitor: #2 monitor\n"));
690 
691   while (!TCR_4(__kmp_global.g.g_done)) {
692     struct timespec now;
693     struct timeval tval;
694 
695     /*  This thread monitors the state of the system */
696 
697     KA_TRACE(15, ("__kmp_launch_monitor: update\n"));
698 
699     status = gettimeofday(&tval, NULL);
700     KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
701     TIMEVAL_TO_TIMESPEC(&tval, &now);
702 
703     now.tv_sec += interval.tv_sec;
704     now.tv_nsec += interval.tv_nsec;
705 
706     if (now.tv_nsec >= KMP_NSEC_PER_SEC) {
707       now.tv_sec += 1;
708       now.tv_nsec -= KMP_NSEC_PER_SEC;
709     }
710 
711     status = pthread_mutex_lock(&__kmp_wait_mx.m_mutex);
712     KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
713     // AC: the monitor should not fall asleep if g_done has been set
714     if (!TCR_4(__kmp_global.g.g_done)) { // check once more under mutex
715       status = pthread_cond_timedwait(&__kmp_wait_cv.c_cond,
716                                       &__kmp_wait_mx.m_mutex, &now);
717       if (status != 0) {
718         if (status != ETIMEDOUT && status != EINTR) {
719           KMP_SYSFAIL("pthread_cond_timedwait", status);
720         }
721       }
722     }
723     status = pthread_mutex_unlock(&__kmp_wait_mx.m_mutex);
724     KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
725 
726     TCW_4(__kmp_global.g.g_time.dt.t_value,
727           TCR_4(__kmp_global.g.g_time.dt.t_value) + 1);
728 
729     KMP_MB(); /* Flush all pending memory write invalidates.  */
730   }
731 
732   KA_TRACE(10, ("__kmp_launch_monitor: #3 cleanup\n"));
733 
734 #ifdef KMP_BLOCK_SIGNALS
735   status = sigfillset(&new_set);
736   KMP_CHECK_SYSFAIL_ERRNO("sigfillset", status);
737   status = pthread_sigmask(SIG_UNBLOCK, &new_set, NULL);
738   KMP_CHECK_SYSFAIL("pthread_sigmask", status);
739 #endif /* KMP_BLOCK_SIGNALS */
740 
741   KA_TRACE(10, ("__kmp_launch_monitor: #4 finished\n"));
742 
743   if (__kmp_global.g.g_abort != 0) {
744     /* now we need to terminate the worker threads  */
745     /* the value of t_abort is the signal we caught */
746 
747     int gtid;
748 
749     KA_TRACE(10, ("__kmp_launch_monitor: #5 terminate sig=%d\n",
750                   __kmp_global.g.g_abort));
751 
752     /* terminate the OpenMP worker threads */
753     /* TODO this is not valid for sibling threads!!
754      * the uber master might not be 0 anymore.. */
755     for (gtid = 1; gtid < __kmp_threads_capacity; ++gtid)
756       __kmp_terminate_thread(gtid);
757 
758     __kmp_cleanup();
759 
760     KA_TRACE(10, ("__kmp_launch_monitor: #6 raise sig=%d\n",
761                   __kmp_global.g.g_abort));
762 
763     if (__kmp_global.g.g_abort > 0)
764       raise(__kmp_global.g.g_abort);
765   }
766 
767   KA_TRACE(10, ("__kmp_launch_monitor: #7 exit\n"));
768 
769   return thr;
770 }
771 #endif // KMP_USE_MONITOR
772 
773 void __kmp_create_worker(int gtid, kmp_info_t *th, size_t stack_size) {
774   pthread_t handle;
775   pthread_attr_t thread_attr;
776   int status;
777 
778   th->th.th_info.ds.ds_gtid = gtid;
779 
780 #if KMP_STATS_ENABLED
781   // sets up worker thread stats
782   __kmp_acquire_tas_lock(&__kmp_stats_lock, gtid);
783 
784   // th->th.th_stats is used to transfer thread-specific stats-pointer to
785   // __kmp_launch_worker. So when thread is created (goes into
786   // __kmp_launch_worker) it will set its thread local pointer to
787   // th->th.th_stats
788   if (!KMP_UBER_GTID(gtid)) {
789     th->th.th_stats = __kmp_stats_list->push_back(gtid);
790   } else {
791     // For root threads, __kmp_stats_thread_ptr is set in __kmp_register_root(),
792     // so set the th->th.th_stats field to it.
793     th->th.th_stats = __kmp_stats_thread_ptr;
794   }
795   __kmp_release_tas_lock(&__kmp_stats_lock, gtid);
796 
797 #endif // KMP_STATS_ENABLED
798 
799   if (KMP_UBER_GTID(gtid)) {
800     KA_TRACE(10, ("__kmp_create_worker: uber thread (%d)\n", gtid));
801     th->th.th_info.ds.ds_thread = pthread_self();
802     __kmp_set_stack_info(gtid, th);
803     __kmp_check_stack_overlap(th);
804     return;
805   }
806 
807   KA_TRACE(10, ("__kmp_create_worker: try to create thread (%d)\n", gtid));
808 
809   KMP_MB(); /* Flush all pending memory write invalidates.  */
810 
811 #ifdef KMP_THREAD_ATTR
812   status = pthread_attr_init(&thread_attr);
813   if (status != 0) {
814     __kmp_fatal(KMP_MSG(CantInitThreadAttrs), KMP_ERR(status), __kmp_msg_null);
815   }
816   status = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_JOINABLE);
817   if (status != 0) {
818     __kmp_fatal(KMP_MSG(CantSetWorkerState), KMP_ERR(status), __kmp_msg_null);
819   }
820 
821   /* Set stack size for this thread now.
822      The multiple of 2 is there because on some machines, requesting an unusual
823      stacksize causes the thread to have an offset before the dummy alloca()
824      takes place to create the offset.  Since we want the user to have a
825      sufficient stacksize AND support a stack offset, we alloca() twice the
826      offset so that the upcoming alloca() does not eliminate any premade offset,
827      and also gives the user the stack space they requested for all threads */
828   stack_size += gtid * __kmp_stkoffset * 2;
829 
830 #if defined(__ANDROID__) && __ANDROID_API__ < 19
831     // Round the stack size to a multiple of the page size. Older versions of
832     // Android (until KitKat) would fail pthread_attr_setstacksize with EINVAL
833     // if the stack size was not a multiple of the page size.
834     stack_size = (stack_size + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1);
835 #endif
836 
837   KA_TRACE(10, ("__kmp_create_worker: T#%d, default stacksize = %lu bytes, "
838                 "__kmp_stksize = %lu bytes, final stacksize = %lu bytes\n",
839                 gtid, KMP_DEFAULT_STKSIZE, __kmp_stksize, stack_size));
840 
841 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
842   status = pthread_attr_setstacksize(&thread_attr, stack_size);
843 #ifdef KMP_BACKUP_STKSIZE
844   if (status != 0) {
845     if (!__kmp_env_stksize) {
846       stack_size = KMP_BACKUP_STKSIZE + gtid * __kmp_stkoffset;
847       __kmp_stksize = KMP_BACKUP_STKSIZE;
848       KA_TRACE(10, ("__kmp_create_worker: T#%d, default stacksize = %lu bytes, "
849                     "__kmp_stksize = %lu bytes, (backup) final stacksize = %lu "
850                     "bytes\n",
851                     gtid, KMP_DEFAULT_STKSIZE, __kmp_stksize, stack_size));
852       status = pthread_attr_setstacksize(&thread_attr, stack_size);
853     }
854   }
855 #endif /* KMP_BACKUP_STKSIZE */
856   if (status != 0) {
857     __kmp_fatal(KMP_MSG(CantSetWorkerStackSize, stack_size), KMP_ERR(status),
858                 KMP_HNT(ChangeWorkerStackSize), __kmp_msg_null);
859   }
860 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
861 
862 #endif /* KMP_THREAD_ATTR */
863 
864   status =
865       pthread_create(&handle, &thread_attr, __kmp_launch_worker, (void *)th);
866   if (status != 0 || !handle) { // ??? Why do we check handle??
867 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
868     if (status == EINVAL) {
869       __kmp_fatal(KMP_MSG(CantSetWorkerStackSize, stack_size), KMP_ERR(status),
870                   KMP_HNT(IncreaseWorkerStackSize), __kmp_msg_null);
871     }
872     if (status == ENOMEM) {
873       __kmp_fatal(KMP_MSG(CantSetWorkerStackSize, stack_size), KMP_ERR(status),
874                   KMP_HNT(DecreaseWorkerStackSize), __kmp_msg_null);
875     }
876 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
877     if (status == EAGAIN) {
878       __kmp_fatal(KMP_MSG(NoResourcesForWorkerThread), KMP_ERR(status),
879                   KMP_HNT(Decrease_NUM_THREADS), __kmp_msg_null);
880     }
881     KMP_SYSFAIL("pthread_create", status);
882   }
883 
884   th->th.th_info.ds.ds_thread = handle;
885 
886 #ifdef KMP_THREAD_ATTR
887   status = pthread_attr_destroy(&thread_attr);
888   if (status) {
889     kmp_msg_t err_code = KMP_ERR(status);
890     __kmp_msg(kmp_ms_warning, KMP_MSG(CantDestroyThreadAttrs), err_code,
891               __kmp_msg_null);
892     if (__kmp_generate_warnings == kmp_warnings_off) {
893       __kmp_str_free(&err_code.str);
894     }
895   }
896 #endif /* KMP_THREAD_ATTR */
897 
898   KMP_MB(); /* Flush all pending memory write invalidates.  */
899 
900   KA_TRACE(10, ("__kmp_create_worker: done creating thread (%d)\n", gtid));
901 
902 } // __kmp_create_worker
903 
904 #if KMP_USE_MONITOR
905 void __kmp_create_monitor(kmp_info_t *th) {
906   pthread_t handle;
907   pthread_attr_t thread_attr;
908   size_t size;
909   int status;
910   int auto_adj_size = FALSE;
911 
912   if (__kmp_dflt_blocktime == KMP_MAX_BLOCKTIME) {
913     // We don't need monitor thread in case of MAX_BLOCKTIME
914     KA_TRACE(10, ("__kmp_create_monitor: skipping monitor thread because of "
915                   "MAX blocktime\n"));
916     th->th.th_info.ds.ds_tid = 0; // this makes reap_monitor no-op
917     th->th.th_info.ds.ds_gtid = 0;
918     return;
919   }
920   KA_TRACE(10, ("__kmp_create_monitor: try to create monitor\n"));
921 
922   KMP_MB(); /* Flush all pending memory write invalidates.  */
923 
924   th->th.th_info.ds.ds_tid = KMP_GTID_MONITOR;
925   th->th.th_info.ds.ds_gtid = KMP_GTID_MONITOR;
926 #if KMP_REAL_TIME_FIX
927   TCW_4(__kmp_global.g.g_time.dt.t_value,
928         -1); // Will use it for synchronization a bit later.
929 #else
930   TCW_4(__kmp_global.g.g_time.dt.t_value, 0);
931 #endif // KMP_REAL_TIME_FIX
932 
933 #ifdef KMP_THREAD_ATTR
934   if (__kmp_monitor_stksize == 0) {
935     __kmp_monitor_stksize = KMP_DEFAULT_MONITOR_STKSIZE;
936     auto_adj_size = TRUE;
937   }
938   status = pthread_attr_init(&thread_attr);
939   if (status != 0) {
940     __kmp_fatal(KMP_MSG(CantInitThreadAttrs), KMP_ERR(status), __kmp_msg_null);
941   }
942   status = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_JOINABLE);
943   if (status != 0) {
944     __kmp_fatal(KMP_MSG(CantSetMonitorState), KMP_ERR(status), __kmp_msg_null);
945   }
946 
947 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
948   status = pthread_attr_getstacksize(&thread_attr, &size);
949   KMP_CHECK_SYSFAIL("pthread_attr_getstacksize", status);
950 #else
951   size = __kmp_sys_min_stksize;
952 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
953 #endif /* KMP_THREAD_ATTR */
954 
955   if (__kmp_monitor_stksize == 0) {
956     __kmp_monitor_stksize = KMP_DEFAULT_MONITOR_STKSIZE;
957   }
958   if (__kmp_monitor_stksize < __kmp_sys_min_stksize) {
959     __kmp_monitor_stksize = __kmp_sys_min_stksize;
960   }
961 
962   KA_TRACE(10, ("__kmp_create_monitor: default stacksize = %lu bytes,"
963                 "requested stacksize = %lu bytes\n",
964                 size, __kmp_monitor_stksize));
965 
966 retry:
967 
968 /* Set stack size for this thread now. */
969 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
970   KA_TRACE(10, ("__kmp_create_monitor: setting stacksize = %lu bytes,",
971                 __kmp_monitor_stksize));
972   status = pthread_attr_setstacksize(&thread_attr, __kmp_monitor_stksize);
973   if (status != 0) {
974     if (auto_adj_size) {
975       __kmp_monitor_stksize *= 2;
976       goto retry;
977     }
978     kmp_msg_t err_code = KMP_ERR(status);
979     __kmp_msg(kmp_ms_warning, // should this be fatal?  BB
980               KMP_MSG(CantSetMonitorStackSize, (long int)__kmp_monitor_stksize),
981               err_code, KMP_HNT(ChangeMonitorStackSize), __kmp_msg_null);
982     if (__kmp_generate_warnings == kmp_warnings_off) {
983       __kmp_str_free(&err_code.str);
984     }
985   }
986 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
987 
988   status =
989       pthread_create(&handle, &thread_attr, __kmp_launch_monitor, (void *)th);
990 
991   if (status != 0) {
992 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
993     if (status == EINVAL) {
994       if (auto_adj_size && (__kmp_monitor_stksize < (size_t)0x40000000)) {
995         __kmp_monitor_stksize *= 2;
996         goto retry;
997       }
998       __kmp_fatal(KMP_MSG(CantSetMonitorStackSize, __kmp_monitor_stksize),
999                   KMP_ERR(status), KMP_HNT(IncreaseMonitorStackSize),
1000                   __kmp_msg_null);
1001     }
1002     if (status == ENOMEM) {
1003       __kmp_fatal(KMP_MSG(CantSetMonitorStackSize, __kmp_monitor_stksize),
1004                   KMP_ERR(status), KMP_HNT(DecreaseMonitorStackSize),
1005                   __kmp_msg_null);
1006     }
1007 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
1008     if (status == EAGAIN) {
1009       __kmp_fatal(KMP_MSG(NoResourcesForMonitorThread), KMP_ERR(status),
1010                   KMP_HNT(DecreaseNumberOfThreadsInUse), __kmp_msg_null);
1011     }
1012     KMP_SYSFAIL("pthread_create", status);
1013   }
1014 
1015   th->th.th_info.ds.ds_thread = handle;
1016 
1017 #if KMP_REAL_TIME_FIX
1018   // Wait for the monitor thread is really started and set its *priority*.
1019   KMP_DEBUG_ASSERT(sizeof(kmp_uint32) ==
1020                    sizeof(__kmp_global.g.g_time.dt.t_value));
1021   __kmp_wait_4((kmp_uint32 volatile *)&__kmp_global.g.g_time.dt.t_value, -1,
1022                &__kmp_neq_4, NULL);
1023 #endif // KMP_REAL_TIME_FIX
1024 
1025 #ifdef KMP_THREAD_ATTR
1026   status = pthread_attr_destroy(&thread_attr);
1027   if (status != 0) {
1028     kmp_msg_t err_code = KMP_ERR(status);
1029     __kmp_msg(kmp_ms_warning, KMP_MSG(CantDestroyThreadAttrs), err_code,
1030               __kmp_msg_null);
1031     if (__kmp_generate_warnings == kmp_warnings_off) {
1032       __kmp_str_free(&err_code.str);
1033     }
1034   }
1035 #endif
1036 
1037   KMP_MB(); /* Flush all pending memory write invalidates.  */
1038 
1039   KA_TRACE(10, ("__kmp_create_monitor: monitor created %#.8lx\n",
1040                 th->th.th_info.ds.ds_thread));
1041 
1042 } // __kmp_create_monitor
1043 #endif // KMP_USE_MONITOR
1044 
1045 void __kmp_exit_thread(int exit_status) {
1046   pthread_exit((void *)(intptr_t)exit_status);
1047 } // __kmp_exit_thread
1048 
1049 #if KMP_USE_MONITOR
1050 void __kmp_resume_monitor();
1051 
1052 void __kmp_reap_monitor(kmp_info_t *th) {
1053   int status;
1054   void *exit_val;
1055 
1056   KA_TRACE(10, ("__kmp_reap_monitor: try to reap monitor thread with handle"
1057                 " %#.8lx\n",
1058                 th->th.th_info.ds.ds_thread));
1059 
1060   // If monitor has been created, its tid and gtid should be KMP_GTID_MONITOR.
1061   // If both tid and gtid are 0, it means the monitor did not ever start.
1062   // If both tid and gtid are KMP_GTID_DNE, the monitor has been shut down.
1063   KMP_DEBUG_ASSERT(th->th.th_info.ds.ds_tid == th->th.th_info.ds.ds_gtid);
1064   if (th->th.th_info.ds.ds_gtid != KMP_GTID_MONITOR) {
1065     KA_TRACE(10, ("__kmp_reap_monitor: monitor did not start, returning\n"));
1066     return;
1067   }
1068 
1069   KMP_MB(); /* Flush all pending memory write invalidates.  */
1070 
1071   /* First, check to see whether the monitor thread exists to wake it up. This
1072      is to avoid performance problem when the monitor sleeps during
1073      blocktime-size interval */
1074 
1075   status = pthread_kill(th->th.th_info.ds.ds_thread, 0);
1076   if (status != ESRCH) {
1077     __kmp_resume_monitor(); // Wake up the monitor thread
1078   }
1079   KA_TRACE(10, ("__kmp_reap_monitor: try to join with monitor\n"));
1080   status = pthread_join(th->th.th_info.ds.ds_thread, &exit_val);
1081   if (exit_val != th) {
1082     __kmp_fatal(KMP_MSG(ReapMonitorError), KMP_ERR(status), __kmp_msg_null);
1083   }
1084 
1085   th->th.th_info.ds.ds_tid = KMP_GTID_DNE;
1086   th->th.th_info.ds.ds_gtid = KMP_GTID_DNE;
1087 
1088   KA_TRACE(10, ("__kmp_reap_monitor: done reaping monitor thread with handle"
1089                 " %#.8lx\n",
1090                 th->th.th_info.ds.ds_thread));
1091 
1092   KMP_MB(); /* Flush all pending memory write invalidates.  */
1093 }
1094 #endif // KMP_USE_MONITOR
1095 
1096 void __kmp_reap_worker(kmp_info_t *th) {
1097   int status;
1098   void *exit_val;
1099 
1100   KMP_MB(); /* Flush all pending memory write invalidates.  */
1101 
1102   KA_TRACE(
1103       10, ("__kmp_reap_worker: try to reap T#%d\n", th->th.th_info.ds.ds_gtid));
1104 
1105   status = pthread_join(th->th.th_info.ds.ds_thread, &exit_val);
1106 #ifdef KMP_DEBUG
1107   /* Don't expose these to the user until we understand when they trigger */
1108   if (status != 0) {
1109     __kmp_fatal(KMP_MSG(ReapWorkerError), KMP_ERR(status), __kmp_msg_null);
1110   }
1111   if (exit_val != th) {
1112     KA_TRACE(10, ("__kmp_reap_worker: worker T#%d did not reap properly, "
1113                   "exit_val = %p\n",
1114                   th->th.th_info.ds.ds_gtid, exit_val));
1115   }
1116 #endif /* KMP_DEBUG */
1117 
1118   KA_TRACE(10, ("__kmp_reap_worker: done reaping T#%d\n",
1119                 th->th.th_info.ds.ds_gtid));
1120 
1121   KMP_MB(); /* Flush all pending memory write invalidates.  */
1122 }
1123 
1124 #if KMP_HANDLE_SIGNALS
1125 
1126 static void __kmp_null_handler(int signo) {
1127   //  Do nothing, for doing SIG_IGN-type actions.
1128 } // __kmp_null_handler
1129 
1130 static void __kmp_team_handler(int signo) {
1131   if (__kmp_global.g.g_abort == 0) {
1132 /* Stage 1 signal handler, let's shut down all of the threads */
1133 #ifdef KMP_DEBUG
1134     __kmp_debug_printf("__kmp_team_handler: caught signal = %d\n", signo);
1135 #endif
1136     switch (signo) {
1137     case SIGHUP:
1138     case SIGINT:
1139     case SIGQUIT:
1140     case SIGILL:
1141     case SIGABRT:
1142     case SIGFPE:
1143     case SIGBUS:
1144     case SIGSEGV:
1145 #ifdef SIGSYS
1146     case SIGSYS:
1147 #endif
1148     case SIGTERM:
1149       if (__kmp_debug_buf) {
1150         __kmp_dump_debug_buffer();
1151       }
1152       KMP_MB(); // Flush all pending memory write invalidates.
1153       TCW_4(__kmp_global.g.g_abort, signo);
1154       KMP_MB(); // Flush all pending memory write invalidates.
1155       TCW_4(__kmp_global.g.g_done, TRUE);
1156       KMP_MB(); // Flush all pending memory write invalidates.
1157       break;
1158     default:
1159 #ifdef KMP_DEBUG
1160       __kmp_debug_printf("__kmp_team_handler: unknown signal type");
1161 #endif
1162       break;
1163     }
1164   }
1165 } // __kmp_team_handler
1166 
1167 static void __kmp_sigaction(int signum, const struct sigaction *act,
1168                             struct sigaction *oldact) {
1169   int rc = sigaction(signum, act, oldact);
1170   KMP_CHECK_SYSFAIL_ERRNO("sigaction", rc);
1171 }
1172 
1173 static void __kmp_install_one_handler(int sig, sig_func_t handler_func,
1174                                       int parallel_init) {
1175   KMP_MB(); // Flush all pending memory write invalidates.
1176   KB_TRACE(60,
1177            ("__kmp_install_one_handler( %d, ..., %d )\n", sig, parallel_init));
1178   if (parallel_init) {
1179     struct sigaction new_action;
1180     struct sigaction old_action;
1181     new_action.sa_handler = handler_func;
1182     new_action.sa_flags = 0;
1183     sigfillset(&new_action.sa_mask);
1184     __kmp_sigaction(sig, &new_action, &old_action);
1185     if (old_action.sa_handler == __kmp_sighldrs[sig].sa_handler) {
1186       sigaddset(&__kmp_sigset, sig);
1187     } else {
1188       // Restore/keep user's handler if one previously installed.
1189       __kmp_sigaction(sig, &old_action, NULL);
1190     }
1191   } else {
1192     // Save initial/system signal handlers to see if user handlers installed.
1193     __kmp_sigaction(sig, NULL, &__kmp_sighldrs[sig]);
1194   }
1195   KMP_MB(); // Flush all pending memory write invalidates.
1196 } // __kmp_install_one_handler
1197 
1198 static void __kmp_remove_one_handler(int sig) {
1199   KB_TRACE(60, ("__kmp_remove_one_handler( %d )\n", sig));
1200   if (sigismember(&__kmp_sigset, sig)) {
1201     struct sigaction old;
1202     KMP_MB(); // Flush all pending memory write invalidates.
1203     __kmp_sigaction(sig, &__kmp_sighldrs[sig], &old);
1204     if ((old.sa_handler != __kmp_team_handler) &&
1205         (old.sa_handler != __kmp_null_handler)) {
1206       // Restore the users signal handler.
1207       KB_TRACE(10, ("__kmp_remove_one_handler: oops, not our handler, "
1208                     "restoring: sig=%d\n",
1209                     sig));
1210       __kmp_sigaction(sig, &old, NULL);
1211     }
1212     sigdelset(&__kmp_sigset, sig);
1213     KMP_MB(); // Flush all pending memory write invalidates.
1214   }
1215 } // __kmp_remove_one_handler
1216 
1217 void __kmp_install_signals(int parallel_init) {
1218   KB_TRACE(10, ("__kmp_install_signals( %d )\n", parallel_init));
1219   if (__kmp_handle_signals || !parallel_init) {
1220     // If ! parallel_init, we do not install handlers, just save original
1221     // handlers. Let us do it even __handle_signals is 0.
1222     sigemptyset(&__kmp_sigset);
1223     __kmp_install_one_handler(SIGHUP, __kmp_team_handler, parallel_init);
1224     __kmp_install_one_handler(SIGINT, __kmp_team_handler, parallel_init);
1225     __kmp_install_one_handler(SIGQUIT, __kmp_team_handler, parallel_init);
1226     __kmp_install_one_handler(SIGILL, __kmp_team_handler, parallel_init);
1227     __kmp_install_one_handler(SIGABRT, __kmp_team_handler, parallel_init);
1228     __kmp_install_one_handler(SIGFPE, __kmp_team_handler, parallel_init);
1229     __kmp_install_one_handler(SIGBUS, __kmp_team_handler, parallel_init);
1230     __kmp_install_one_handler(SIGSEGV, __kmp_team_handler, parallel_init);
1231 #ifdef SIGSYS
1232     __kmp_install_one_handler(SIGSYS, __kmp_team_handler, parallel_init);
1233 #endif // SIGSYS
1234     __kmp_install_one_handler(SIGTERM, __kmp_team_handler, parallel_init);
1235 #ifdef SIGPIPE
1236     __kmp_install_one_handler(SIGPIPE, __kmp_team_handler, parallel_init);
1237 #endif // SIGPIPE
1238   }
1239 } // __kmp_install_signals
1240 
1241 void __kmp_remove_signals(void) {
1242   int sig;
1243   KB_TRACE(10, ("__kmp_remove_signals()\n"));
1244   for (sig = 1; sig < NSIG; ++sig) {
1245     __kmp_remove_one_handler(sig);
1246   }
1247 } // __kmp_remove_signals
1248 
1249 #endif // KMP_HANDLE_SIGNALS
1250 
1251 void __kmp_enable(int new_state) {
1252 #ifdef KMP_CANCEL_THREADS
1253   int status, old_state;
1254   status = pthread_setcancelstate(new_state, &old_state);
1255   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
1256   KMP_DEBUG_ASSERT(old_state == PTHREAD_CANCEL_DISABLE);
1257 #endif
1258 }
1259 
1260 void __kmp_disable(int *old_state) {
1261 #ifdef KMP_CANCEL_THREADS
1262   int status;
1263   status = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, old_state);
1264   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
1265 #endif
1266 }
1267 
1268 static void __kmp_atfork_prepare(void) {
1269   __kmp_acquire_bootstrap_lock(&__kmp_initz_lock);
1270   __kmp_acquire_bootstrap_lock(&__kmp_forkjoin_lock);
1271 }
1272 
1273 static void __kmp_atfork_parent(void) {
1274   __kmp_release_bootstrap_lock(&__kmp_initz_lock);
1275   __kmp_release_bootstrap_lock(&__kmp_forkjoin_lock);
1276 }
1277 
1278 /* Reset the library so execution in the child starts "all over again" with
1279    clean data structures in initial states.  Don't worry about freeing memory
1280    allocated by parent, just abandon it to be safe. */
1281 static void __kmp_atfork_child(void) {
1282   __kmp_release_bootstrap_lock(&__kmp_forkjoin_lock);
1283   /* TODO make sure this is done right for nested/sibling */
1284   // ATT:  Memory leaks are here? TODO: Check it and fix.
1285   /* KMP_ASSERT( 0 ); */
1286 
1287   ++__kmp_fork_count;
1288 
1289 #if KMP_AFFINITY_SUPPORTED
1290 #if KMP_OS_LINUX || KMP_OS_FREEBSD
1291   // reset the affinity in the child to the initial thread
1292   // affinity in the parent
1293   kmp_set_thread_affinity_mask_initial();
1294 #endif
1295   // Set default not to bind threads tightly in the child (we’re expecting
1296   // over-subscription after the fork and this can improve things for
1297   // scripting languages that use OpenMP inside process-parallel code).
1298   __kmp_affinity_type = affinity_none;
1299   if (__kmp_nested_proc_bind.bind_types != NULL) {
1300     __kmp_nested_proc_bind.bind_types[0] = proc_bind_false;
1301   }
1302 #endif // KMP_AFFINITY_SUPPORTED
1303 
1304   __kmp_init_runtime = FALSE;
1305 #if KMP_USE_MONITOR
1306   __kmp_init_monitor = 0;
1307 #endif
1308   __kmp_init_parallel = FALSE;
1309   __kmp_init_middle = FALSE;
1310   __kmp_init_serial = FALSE;
1311   TCW_4(__kmp_init_gtid, FALSE);
1312   __kmp_init_common = FALSE;
1313 
1314   TCW_4(__kmp_init_user_locks, FALSE);
1315 #if !KMP_USE_DYNAMIC_LOCK
1316   __kmp_user_lock_table.used = 1;
1317   __kmp_user_lock_table.allocated = 0;
1318   __kmp_user_lock_table.table = NULL;
1319   __kmp_lock_blocks = NULL;
1320 #endif
1321 
1322   __kmp_all_nth = 0;
1323   TCW_4(__kmp_nth, 0);
1324 
1325   __kmp_thread_pool = NULL;
1326   __kmp_thread_pool_insert_pt = NULL;
1327   __kmp_team_pool = NULL;
1328 
1329   /* Must actually zero all the *cache arguments passed to __kmpc_threadprivate
1330      here so threadprivate doesn't use stale data */
1331   KA_TRACE(10, ("__kmp_atfork_child: checking cache address list %p\n",
1332                 __kmp_threadpriv_cache_list));
1333 
1334   while (__kmp_threadpriv_cache_list != NULL) {
1335 
1336     if (*__kmp_threadpriv_cache_list->addr != NULL) {
1337       KC_TRACE(50, ("__kmp_atfork_child: zeroing cache at address %p\n",
1338                     &(*__kmp_threadpriv_cache_list->addr)));
1339 
1340       *__kmp_threadpriv_cache_list->addr = NULL;
1341     }
1342     __kmp_threadpriv_cache_list = __kmp_threadpriv_cache_list->next;
1343   }
1344 
1345   __kmp_init_runtime = FALSE;
1346 
1347   /* reset statically initialized locks */
1348   __kmp_init_bootstrap_lock(&__kmp_initz_lock);
1349   __kmp_init_bootstrap_lock(&__kmp_stdio_lock);
1350   __kmp_init_bootstrap_lock(&__kmp_console_lock);
1351   __kmp_init_bootstrap_lock(&__kmp_task_team_lock);
1352 
1353 #if USE_ITT_BUILD
1354   __kmp_itt_reset(); // reset ITT's global state
1355 #endif /* USE_ITT_BUILD */
1356 
1357   /* This is necessary to make sure no stale data is left around */
1358   /* AC: customers complain that we use unsafe routines in the atfork
1359      handler. Mathworks: dlsym() is unsafe. We call dlsym and dlopen
1360      in dynamic_link when check the presence of shared tbbmalloc library.
1361      Suggestion is to make the library initialization lazier, similar
1362      to what done for __kmpc_begin(). */
1363   // TODO: synchronize all static initializations with regular library
1364   //       startup; look at kmp_global.cpp and etc.
1365   //__kmp_internal_begin ();
1366 }
1367 
1368 void __kmp_register_atfork(void) {
1369   if (__kmp_need_register_atfork) {
1370     int status = pthread_atfork(__kmp_atfork_prepare, __kmp_atfork_parent,
1371                                 __kmp_atfork_child);
1372     KMP_CHECK_SYSFAIL("pthread_atfork", status);
1373     __kmp_need_register_atfork = FALSE;
1374   }
1375 }
1376 
1377 void __kmp_suspend_initialize(void) {
1378   int status;
1379   status = pthread_mutexattr_init(&__kmp_suspend_mutex_attr);
1380   KMP_CHECK_SYSFAIL("pthread_mutexattr_init", status);
1381   status = pthread_condattr_init(&__kmp_suspend_cond_attr);
1382   KMP_CHECK_SYSFAIL("pthread_condattr_init", status);
1383 }
1384 
1385 void __kmp_suspend_initialize_thread(kmp_info_t *th) {
1386   ANNOTATE_HAPPENS_AFTER(&th->th.th_suspend_init_count);
1387   int old_value = KMP_ATOMIC_LD_RLX(&th->th.th_suspend_init_count);
1388   int new_value = __kmp_fork_count + 1;
1389   // Return if already initialized
1390   if (old_value == new_value)
1391     return;
1392   // Wait, then return if being initialized
1393   if (old_value == -1 ||
1394       !__kmp_atomic_compare_store(&th->th.th_suspend_init_count, old_value,
1395                                   -1)) {
1396     while (KMP_ATOMIC_LD_ACQ(&th->th.th_suspend_init_count) != new_value) {
1397       KMP_CPU_PAUSE();
1398     }
1399   } else {
1400     // Claim to be the initializer and do initializations
1401     int status;
1402     status = pthread_cond_init(&th->th.th_suspend_cv.c_cond,
1403                                &__kmp_suspend_cond_attr);
1404     KMP_CHECK_SYSFAIL("pthread_cond_init", status);
1405     status = pthread_mutex_init(&th->th.th_suspend_mx.m_mutex,
1406                                 &__kmp_suspend_mutex_attr);
1407     KMP_CHECK_SYSFAIL("pthread_mutex_init", status);
1408     KMP_ATOMIC_ST_REL(&th->th.th_suspend_init_count, new_value);
1409     ANNOTATE_HAPPENS_BEFORE(&th->th.th_suspend_init_count);
1410   }
1411 }
1412 
1413 void __kmp_suspend_uninitialize_thread(kmp_info_t *th) {
1414   if (KMP_ATOMIC_LD_ACQ(&th->th.th_suspend_init_count) > __kmp_fork_count) {
1415     /* this means we have initialize the suspension pthread objects for this
1416        thread in this instance of the process */
1417     int status;
1418 
1419     status = pthread_cond_destroy(&th->th.th_suspend_cv.c_cond);
1420     if (status != 0 && status != EBUSY) {
1421       KMP_SYSFAIL("pthread_cond_destroy", status);
1422     }
1423     status = pthread_mutex_destroy(&th->th.th_suspend_mx.m_mutex);
1424     if (status != 0 && status != EBUSY) {
1425       KMP_SYSFAIL("pthread_mutex_destroy", status);
1426     }
1427     --th->th.th_suspend_init_count;
1428     KMP_DEBUG_ASSERT(KMP_ATOMIC_LD_RLX(&th->th.th_suspend_init_count) ==
1429                      __kmp_fork_count);
1430   }
1431 }
1432 
1433 // return true if lock obtained, false otherwise
1434 int __kmp_try_suspend_mx(kmp_info_t *th) {
1435   return (pthread_mutex_trylock(&th->th.th_suspend_mx.m_mutex) == 0);
1436 }
1437 
1438 void __kmp_lock_suspend_mx(kmp_info_t *th) {
1439   int status = pthread_mutex_lock(&th->th.th_suspend_mx.m_mutex);
1440   KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
1441 }
1442 
1443 void __kmp_unlock_suspend_mx(kmp_info_t *th) {
1444   int status = pthread_mutex_unlock(&th->th.th_suspend_mx.m_mutex);
1445   KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1446 }
1447 
1448 /* This routine puts the calling thread to sleep after setting the
1449    sleep bit for the indicated flag variable to true. */
1450 template <class C>
1451 static inline void __kmp_suspend_template(int th_gtid, C *flag) {
1452   KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_suspend);
1453   kmp_info_t *th = __kmp_threads[th_gtid];
1454   int status;
1455   typename C::flag_t old_spin;
1456 
1457   KF_TRACE(30, ("__kmp_suspend_template: T#%d enter for flag = %p\n", th_gtid,
1458                 flag->get()));
1459 
1460   __kmp_suspend_initialize_thread(th);
1461 
1462   __kmp_lock_suspend_mx(th);
1463 
1464   KF_TRACE(10, ("__kmp_suspend_template: T#%d setting sleep bit for spin(%p)\n",
1465                 th_gtid, flag->get()));
1466 
1467   /* TODO: shouldn't this use release semantics to ensure that
1468      __kmp_suspend_initialize_thread gets called first? */
1469   old_spin = flag->set_sleeping();
1470   if (__kmp_dflt_blocktime == KMP_MAX_BLOCKTIME &&
1471       __kmp_pause_status != kmp_soft_paused) {
1472     flag->unset_sleeping();
1473     __kmp_unlock_suspend_mx(th);
1474     return;
1475   }
1476   KF_TRACE(5, ("__kmp_suspend_template: T#%d set sleep bit for spin(%p)==%x,"
1477                " was %x\n",
1478                th_gtid, flag->get(), flag->load(), old_spin));
1479 
1480   if (flag->done_check_val(old_spin)) {
1481     old_spin = flag->unset_sleeping();
1482     KF_TRACE(5, ("__kmp_suspend_template: T#%d false alarm, reset sleep bit "
1483                  "for spin(%p)\n",
1484                  th_gtid, flag->get()));
1485   } else {
1486     /* Encapsulate in a loop as the documentation states that this may
1487        "with low probability" return when the condition variable has
1488        not been signaled or broadcast */
1489     int deactivated = FALSE;
1490     TCW_PTR(th->th.th_sleep_loc, (void *)flag);
1491 
1492     while (flag->is_sleeping()) {
1493 #ifdef DEBUG_SUSPEND
1494       char buffer[128];
1495       __kmp_suspend_count++;
1496       __kmp_print_cond(buffer, &th->th.th_suspend_cv);
1497       __kmp_printf("__kmp_suspend_template: suspending T#%d: %s\n", th_gtid,
1498                    buffer);
1499 #endif
1500       // Mark the thread as no longer active (only in the first iteration of the
1501       // loop).
1502       if (!deactivated) {
1503         th->th.th_active = FALSE;
1504         if (th->th.th_active_in_pool) {
1505           th->th.th_active_in_pool = FALSE;
1506           KMP_ATOMIC_DEC(&__kmp_thread_pool_active_nth);
1507           KMP_DEBUG_ASSERT(TCR_4(__kmp_thread_pool_active_nth) >= 0);
1508         }
1509         deactivated = TRUE;
1510       }
1511 
1512 #if USE_SUSPEND_TIMEOUT
1513       struct timespec now;
1514       struct timeval tval;
1515       int msecs;
1516 
1517       status = gettimeofday(&tval, NULL);
1518       KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1519       TIMEVAL_TO_TIMESPEC(&tval, &now);
1520 
1521       msecs = (4 * __kmp_dflt_blocktime) + 200;
1522       now.tv_sec += msecs / 1000;
1523       now.tv_nsec += (msecs % 1000) * 1000;
1524 
1525       KF_TRACE(15, ("__kmp_suspend_template: T#%d about to perform "
1526                     "pthread_cond_timedwait\n",
1527                     th_gtid));
1528       status = pthread_cond_timedwait(&th->th.th_suspend_cv.c_cond,
1529                                       &th->th.th_suspend_mx.m_mutex, &now);
1530 #else
1531       KF_TRACE(15, ("__kmp_suspend_template: T#%d about to perform"
1532                     " pthread_cond_wait\n",
1533                     th_gtid));
1534       status = pthread_cond_wait(&th->th.th_suspend_cv.c_cond,
1535                                  &th->th.th_suspend_mx.m_mutex);
1536 #endif // USE_SUSPEND_TIMEOUT
1537 
1538       if ((status != 0) && (status != EINTR) && (status != ETIMEDOUT)) {
1539         KMP_SYSFAIL("pthread_cond_wait", status);
1540       }
1541 #ifdef KMP_DEBUG
1542       if (status == ETIMEDOUT) {
1543         if (flag->is_sleeping()) {
1544           KF_TRACE(100,
1545                    ("__kmp_suspend_template: T#%d timeout wakeup\n", th_gtid));
1546         } else {
1547           KF_TRACE(2, ("__kmp_suspend_template: T#%d timeout wakeup, sleep bit "
1548                        "not set!\n",
1549                        th_gtid));
1550         }
1551       } else if (flag->is_sleeping()) {
1552         KF_TRACE(100,
1553                  ("__kmp_suspend_template: T#%d spurious wakeup\n", th_gtid));
1554       }
1555 #endif
1556     } // while
1557 
1558     // Mark the thread as active again (if it was previous marked as inactive)
1559     if (deactivated) {
1560       th->th.th_active = TRUE;
1561       if (TCR_4(th->th.th_in_pool)) {
1562         KMP_ATOMIC_INC(&__kmp_thread_pool_active_nth);
1563         th->th.th_active_in_pool = TRUE;
1564       }
1565     }
1566   }
1567 #ifdef DEBUG_SUSPEND
1568   {
1569     char buffer[128];
1570     __kmp_print_cond(buffer, &th->th.th_suspend_cv);
1571     __kmp_printf("__kmp_suspend_template: T#%d has awakened: %s\n", th_gtid,
1572                  buffer);
1573   }
1574 #endif
1575 
1576   __kmp_unlock_suspend_mx(th);
1577   KF_TRACE(30, ("__kmp_suspend_template: T#%d exit\n", th_gtid));
1578 }
1579 
1580 template <bool C, bool S>
1581 void __kmp_suspend_32(int th_gtid, kmp_flag_32<C, S> *flag) {
1582   __kmp_suspend_template(th_gtid, flag);
1583 }
1584 template <bool C, bool S>
1585 void __kmp_suspend_64(int th_gtid, kmp_flag_64<C, S> *flag) {
1586   __kmp_suspend_template(th_gtid, flag);
1587 }
1588 void __kmp_suspend_oncore(int th_gtid, kmp_flag_oncore *flag) {
1589   __kmp_suspend_template(th_gtid, flag);
1590 }
1591 
1592 template void __kmp_suspend_32<false, false>(int, kmp_flag_32<false, false> *);
1593 template void __kmp_suspend_64<false, true>(int, kmp_flag_64<false, true> *);
1594 template void __kmp_suspend_64<true, false>(int, kmp_flag_64<true, false> *);
1595 
1596 /* This routine signals the thread specified by target_gtid to wake up
1597    after setting the sleep bit indicated by the flag argument to FALSE.
1598    The target thread must already have called __kmp_suspend_template() */
1599 template <class C>
1600 static inline void __kmp_resume_template(int target_gtid, C *flag) {
1601   KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_resume);
1602   kmp_info_t *th = __kmp_threads[target_gtid];
1603   int status;
1604 
1605 #ifdef KMP_DEBUG
1606   int gtid = TCR_4(__kmp_init_gtid) ? __kmp_get_gtid() : -1;
1607 #endif
1608 
1609   KF_TRACE(30, ("__kmp_resume_template: T#%d wants to wakeup T#%d enter\n",
1610                 gtid, target_gtid));
1611   KMP_DEBUG_ASSERT(gtid != target_gtid);
1612 
1613   __kmp_suspend_initialize_thread(th);
1614   __kmp_lock_suspend_mx(th);
1615 
1616   if (!flag) { // coming from __kmp_null_resume_wrapper
1617     flag = (C *)CCAST(void *, th->th.th_sleep_loc);
1618   }
1619 
1620   // First, check if the flag is null or its type has changed. If so, someone
1621   // else woke it up.
1622   if (!flag || flag->get_type() != flag->get_ptr_type()) { // get_ptr_type
1623     // simply shows what flag was cast to
1624     KF_TRACE(5, ("__kmp_resume_template: T#%d exiting, thread T#%d already "
1625                  "awake: flag(%p)\n",
1626                  gtid, target_gtid, NULL));
1627     __kmp_unlock_suspend_mx(th);
1628     return;
1629   } else { // if multiple threads are sleeping, flag should be internally
1630     // referring to a specific thread here
1631     typename C::flag_t old_spin = flag->unset_sleeping();
1632     if (!flag->is_sleeping_val(old_spin)) {
1633       KF_TRACE(5, ("__kmp_resume_template: T#%d exiting, thread T#%d already "
1634                    "awake: flag(%p): "
1635                    "%u => %u\n",
1636                    gtid, target_gtid, flag->get(), old_spin, flag->load()));
1637       __kmp_unlock_suspend_mx(th);
1638       return;
1639     }
1640     KF_TRACE(5, ("__kmp_resume_template: T#%d about to wakeup T#%d, reset "
1641                  "sleep bit for flag's loc(%p): "
1642                  "%u => %u\n",
1643                  gtid, target_gtid, flag->get(), old_spin, flag->load()));
1644   }
1645   TCW_PTR(th->th.th_sleep_loc, NULL);
1646 
1647 #ifdef DEBUG_SUSPEND
1648   {
1649     char buffer[128];
1650     __kmp_print_cond(buffer, &th->th.th_suspend_cv);
1651     __kmp_printf("__kmp_resume_template: T#%d resuming T#%d: %s\n", gtid,
1652                  target_gtid, buffer);
1653   }
1654 #endif
1655   status = pthread_cond_signal(&th->th.th_suspend_cv.c_cond);
1656   KMP_CHECK_SYSFAIL("pthread_cond_signal", status);
1657   __kmp_unlock_suspend_mx(th);
1658   KF_TRACE(30, ("__kmp_resume_template: T#%d exiting after signaling wake up"
1659                 " for T#%d\n",
1660                 gtid, target_gtid));
1661 }
1662 
1663 template <bool C, bool S>
1664 void __kmp_resume_32(int target_gtid, kmp_flag_32<C, S> *flag) {
1665   __kmp_resume_template(target_gtid, flag);
1666 }
1667 template <bool C, bool S>
1668 void __kmp_resume_64(int target_gtid, kmp_flag_64<C, S> *flag) {
1669   __kmp_resume_template(target_gtid, flag);
1670 }
1671 void __kmp_resume_oncore(int target_gtid, kmp_flag_oncore *flag) {
1672   __kmp_resume_template(target_gtid, flag);
1673 }
1674 
1675 template void __kmp_resume_32<false, true>(int, kmp_flag_32<false, true> *);
1676 template void __kmp_resume_64<false, true>(int, kmp_flag_64<false, true> *);
1677 
1678 #if KMP_USE_MONITOR
1679 void __kmp_resume_monitor() {
1680   KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_resume);
1681   int status;
1682 #ifdef KMP_DEBUG
1683   int gtid = TCR_4(__kmp_init_gtid) ? __kmp_get_gtid() : -1;
1684   KF_TRACE(30, ("__kmp_resume_monitor: T#%d wants to wakeup T#%d enter\n", gtid,
1685                 KMP_GTID_MONITOR));
1686   KMP_DEBUG_ASSERT(gtid != KMP_GTID_MONITOR);
1687 #endif
1688   status = pthread_mutex_lock(&__kmp_wait_mx.m_mutex);
1689   KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
1690 #ifdef DEBUG_SUSPEND
1691   {
1692     char buffer[128];
1693     __kmp_print_cond(buffer, &__kmp_wait_cv.c_cond);
1694     __kmp_printf("__kmp_resume_monitor: T#%d resuming T#%d: %s\n", gtid,
1695                  KMP_GTID_MONITOR, buffer);
1696   }
1697 #endif
1698   status = pthread_cond_signal(&__kmp_wait_cv.c_cond);
1699   KMP_CHECK_SYSFAIL("pthread_cond_signal", status);
1700   status = pthread_mutex_unlock(&__kmp_wait_mx.m_mutex);
1701   KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1702   KF_TRACE(30, ("__kmp_resume_monitor: T#%d exiting after signaling wake up"
1703                 " for T#%d\n",
1704                 gtid, KMP_GTID_MONITOR));
1705 }
1706 #endif // KMP_USE_MONITOR
1707 
1708 void __kmp_yield() { sched_yield(); }
1709 
1710 void __kmp_gtid_set_specific(int gtid) {
1711   if (__kmp_init_gtid) {
1712     int status;
1713     status = pthread_setspecific(__kmp_gtid_threadprivate_key,
1714                                  (void *)(intptr_t)(gtid + 1));
1715     KMP_CHECK_SYSFAIL("pthread_setspecific", status);
1716   } else {
1717     KA_TRACE(50, ("__kmp_gtid_set_specific: runtime shutdown, returning\n"));
1718   }
1719 }
1720 
1721 int __kmp_gtid_get_specific() {
1722   int gtid;
1723   if (!__kmp_init_gtid) {
1724     KA_TRACE(50, ("__kmp_gtid_get_specific: runtime shutdown, returning "
1725                   "KMP_GTID_SHUTDOWN\n"));
1726     return KMP_GTID_SHUTDOWN;
1727   }
1728   gtid = (int)(size_t)pthread_getspecific(__kmp_gtid_threadprivate_key);
1729   if (gtid == 0) {
1730     gtid = KMP_GTID_DNE;
1731   } else {
1732     gtid--;
1733   }
1734   KA_TRACE(50, ("__kmp_gtid_get_specific: key:%d gtid:%d\n",
1735                 __kmp_gtid_threadprivate_key, gtid));
1736   return gtid;
1737 }
1738 
1739 double __kmp_read_cpu_time(void) {
1740   /*clock_t   t;*/
1741   struct tms buffer;
1742 
1743   /*t =*/times(&buffer);
1744 
1745   return (buffer.tms_utime + buffer.tms_cutime) / (double)CLOCKS_PER_SEC;
1746 }
1747 
1748 int __kmp_read_system_info(struct kmp_sys_info *info) {
1749   int status;
1750   struct rusage r_usage;
1751 
1752   memset(info, 0, sizeof(*info));
1753 
1754   status = getrusage(RUSAGE_SELF, &r_usage);
1755   KMP_CHECK_SYSFAIL_ERRNO("getrusage", status);
1756 
1757   // The maximum resident set size utilized (in kilobytes)
1758   info->maxrss = r_usage.ru_maxrss;
1759   // The number of page faults serviced without any I/O
1760   info->minflt = r_usage.ru_minflt;
1761   // The number of page faults serviced that required I/O
1762   info->majflt = r_usage.ru_majflt;
1763   // The number of times a process was "swapped" out of memory
1764   info->nswap = r_usage.ru_nswap;
1765   // The number of times the file system had to perform input
1766   info->inblock = r_usage.ru_inblock;
1767   // The number of times the file system had to perform output
1768   info->oublock = r_usage.ru_oublock;
1769   // The number of times a context switch was voluntarily
1770   info->nvcsw = r_usage.ru_nvcsw;
1771   // The number of times a context switch was forced
1772   info->nivcsw = r_usage.ru_nivcsw;
1773 
1774   return (status != 0);
1775 }
1776 
1777 void __kmp_read_system_time(double *delta) {
1778   double t_ns;
1779   struct timeval tval;
1780   struct timespec stop;
1781   int status;
1782 
1783   status = gettimeofday(&tval, NULL);
1784   KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1785   TIMEVAL_TO_TIMESPEC(&tval, &stop);
1786   t_ns = TS2NS(stop) - TS2NS(__kmp_sys_timer_data.start);
1787   *delta = (t_ns * 1e-9);
1788 }
1789 
1790 void __kmp_clear_system_time(void) {
1791   struct timeval tval;
1792   int status;
1793   status = gettimeofday(&tval, NULL);
1794   KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1795   TIMEVAL_TO_TIMESPEC(&tval, &__kmp_sys_timer_data.start);
1796 }
1797 
1798 static int __kmp_get_xproc(void) {
1799 
1800   int r = 0;
1801 
1802 #if KMP_OS_LINUX || KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD ||     \
1803         KMP_OS_OPENBSD || KMP_OS_HURD
1804 
1805   r = sysconf(_SC_NPROCESSORS_ONLN);
1806 
1807 #elif KMP_OS_DARWIN
1808 
1809   // Bug C77011 High "OpenMP Threads and number of active cores".
1810 
1811   // Find the number of available CPUs.
1812   kern_return_t rc;
1813   host_basic_info_data_t info;
1814   mach_msg_type_number_t num = HOST_BASIC_INFO_COUNT;
1815   rc = host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&info, &num);
1816   if (rc == 0 && num == HOST_BASIC_INFO_COUNT) {
1817     // Cannot use KA_TRACE() here because this code works before trace support
1818     // is initialized.
1819     r = info.avail_cpus;
1820   } else {
1821     KMP_WARNING(CantGetNumAvailCPU);
1822     KMP_INFORM(AssumedNumCPU);
1823   }
1824 
1825 #else
1826 
1827 #error "Unknown or unsupported OS."
1828 
1829 #endif
1830 
1831   return r > 0 ? r : 2; /* guess value of 2 if OS told us 0 */
1832 
1833 } // __kmp_get_xproc
1834 
1835 int __kmp_read_from_file(char const *path, char const *format, ...) {
1836   int result;
1837   va_list args;
1838 
1839   va_start(args, format);
1840   FILE *f = fopen(path, "rb");
1841   if (f == NULL)
1842     return 0;
1843   result = vfscanf(f, format, args);
1844   fclose(f);
1845 
1846   return result;
1847 }
1848 
1849 void __kmp_runtime_initialize(void) {
1850   int status;
1851   pthread_mutexattr_t mutex_attr;
1852   pthread_condattr_t cond_attr;
1853 
1854   if (__kmp_init_runtime) {
1855     return;
1856   }
1857 
1858 #if (KMP_ARCH_X86 || KMP_ARCH_X86_64)
1859   if (!__kmp_cpuinfo.initialized) {
1860     __kmp_query_cpuid(&__kmp_cpuinfo);
1861   }
1862 #endif /* KMP_ARCH_X86 || KMP_ARCH_X86_64 */
1863 
1864   __kmp_xproc = __kmp_get_xproc();
1865 
1866 #if ! KMP_32_BIT_ARCH
1867   struct rlimit rlim;
1868   // read stack size of calling thread, save it as default for worker threads;
1869   // this should be done before reading environment variables
1870   status = getrlimit(RLIMIT_STACK, &rlim);
1871   if (status == 0) { // success?
1872     __kmp_stksize = rlim.rlim_cur;
1873     __kmp_check_stksize(&__kmp_stksize); // check value and adjust if needed
1874   }
1875 #endif /* KMP_32_BIT_ARCH */
1876 
1877   if (sysconf(_SC_THREADS)) {
1878 
1879     /* Query the maximum number of threads */
1880     __kmp_sys_max_nth = sysconf(_SC_THREAD_THREADS_MAX);
1881     if (__kmp_sys_max_nth == -1) {
1882       /* Unlimited threads for NPTL */
1883       __kmp_sys_max_nth = INT_MAX;
1884     } else if (__kmp_sys_max_nth <= 1) {
1885       /* Can't tell, just use PTHREAD_THREADS_MAX */
1886       __kmp_sys_max_nth = KMP_MAX_NTH;
1887     }
1888 
1889     /* Query the minimum stack size */
1890     __kmp_sys_min_stksize = sysconf(_SC_THREAD_STACK_MIN);
1891     if (__kmp_sys_min_stksize <= 1) {
1892       __kmp_sys_min_stksize = KMP_MIN_STKSIZE;
1893     }
1894   }
1895 
1896   /* Set up minimum number of threads to switch to TLS gtid */
1897   __kmp_tls_gtid_min = KMP_TLS_GTID_MIN;
1898 
1899   status = pthread_key_create(&__kmp_gtid_threadprivate_key,
1900                               __kmp_internal_end_dest);
1901   KMP_CHECK_SYSFAIL("pthread_key_create", status);
1902   status = pthread_mutexattr_init(&mutex_attr);
1903   KMP_CHECK_SYSFAIL("pthread_mutexattr_init", status);
1904   status = pthread_mutex_init(&__kmp_wait_mx.m_mutex, &mutex_attr);
1905   KMP_CHECK_SYSFAIL("pthread_mutex_init", status);
1906   status = pthread_condattr_init(&cond_attr);
1907   KMP_CHECK_SYSFAIL("pthread_condattr_init", status);
1908   status = pthread_cond_init(&__kmp_wait_cv.c_cond, &cond_attr);
1909   KMP_CHECK_SYSFAIL("pthread_cond_init", status);
1910 #if USE_ITT_BUILD
1911   __kmp_itt_initialize();
1912 #endif /* USE_ITT_BUILD */
1913 
1914   __kmp_init_runtime = TRUE;
1915 }
1916 
1917 void __kmp_runtime_destroy(void) {
1918   int status;
1919 
1920   if (!__kmp_init_runtime) {
1921     return; // Nothing to do.
1922   }
1923 
1924 #if USE_ITT_BUILD
1925   __kmp_itt_destroy();
1926 #endif /* USE_ITT_BUILD */
1927 
1928   status = pthread_key_delete(__kmp_gtid_threadprivate_key);
1929   KMP_CHECK_SYSFAIL("pthread_key_delete", status);
1930 
1931   status = pthread_mutex_destroy(&__kmp_wait_mx.m_mutex);
1932   if (status != 0 && status != EBUSY) {
1933     KMP_SYSFAIL("pthread_mutex_destroy", status);
1934   }
1935   status = pthread_cond_destroy(&__kmp_wait_cv.c_cond);
1936   if (status != 0 && status != EBUSY) {
1937     KMP_SYSFAIL("pthread_cond_destroy", status);
1938   }
1939 #if KMP_AFFINITY_SUPPORTED
1940   __kmp_affinity_uninitialize();
1941 #endif
1942 
1943   __kmp_init_runtime = FALSE;
1944 }
1945 
1946 /* Put the thread to sleep for a time period */
1947 /* NOTE: not currently used anywhere */
1948 void __kmp_thread_sleep(int millis) { sleep((millis + 500) / 1000); }
1949 
1950 /* Calculate the elapsed wall clock time for the user */
1951 void __kmp_elapsed(double *t) {
1952   int status;
1953 #ifdef FIX_SGI_CLOCK
1954   struct timespec ts;
1955 
1956   status = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
1957   KMP_CHECK_SYSFAIL_ERRNO("clock_gettime", status);
1958   *t =
1959       (double)ts.tv_nsec * (1.0 / (double)KMP_NSEC_PER_SEC) + (double)ts.tv_sec;
1960 #else
1961   struct timeval tv;
1962 
1963   status = gettimeofday(&tv, NULL);
1964   KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1965   *t =
1966       (double)tv.tv_usec * (1.0 / (double)KMP_USEC_PER_SEC) + (double)tv.tv_sec;
1967 #endif
1968 }
1969 
1970 /* Calculate the elapsed wall clock tick for the user */
1971 void __kmp_elapsed_tick(double *t) { *t = 1 / (double)CLOCKS_PER_SEC; }
1972 
1973 /* Return the current time stamp in nsec */
1974 kmp_uint64 __kmp_now_nsec() {
1975   struct timeval t;
1976   gettimeofday(&t, NULL);
1977   kmp_uint64 nsec = (kmp_uint64)KMP_NSEC_PER_SEC * (kmp_uint64)t.tv_sec +
1978                     (kmp_uint64)1000 * (kmp_uint64)t.tv_usec;
1979   return nsec;
1980 }
1981 
1982 #if KMP_ARCH_X86 || KMP_ARCH_X86_64
1983 /* Measure clock ticks per millisecond */
1984 void __kmp_initialize_system_tick() {
1985   kmp_uint64 now, nsec2, diff;
1986   kmp_uint64 delay = 100000; // 50~100 usec on most machines.
1987   kmp_uint64 nsec = __kmp_now_nsec();
1988   kmp_uint64 goal = __kmp_hardware_timestamp() + delay;
1989   while ((now = __kmp_hardware_timestamp()) < goal)
1990     ;
1991   nsec2 = __kmp_now_nsec();
1992   diff = nsec2 - nsec;
1993   if (diff > 0) {
1994     kmp_uint64 tpms = (kmp_uint64)(1e6 * (delay + (now - goal)) / diff);
1995     if (tpms > 0)
1996       __kmp_ticks_per_msec = tpms;
1997   }
1998 }
1999 #endif
2000 
2001 /* Determine whether the given address is mapped into the current address
2002    space. */
2003 
2004 int __kmp_is_address_mapped(void *addr) {
2005 
2006   int found = 0;
2007   int rc;
2008 
2009 #if KMP_OS_LINUX || KMP_OS_HURD
2010 
2011   /* On GNUish OSes, read the /proc/<pid>/maps pseudo-file to get all the address
2012      ranges mapped into the address space. */
2013 
2014   char *name = __kmp_str_format("/proc/%d/maps", getpid());
2015   FILE *file = NULL;
2016 
2017   file = fopen(name, "r");
2018   KMP_ASSERT(file != NULL);
2019 
2020   for (;;) {
2021 
2022     void *beginning = NULL;
2023     void *ending = NULL;
2024     char perms[5];
2025 
2026     rc = fscanf(file, "%p-%p %4s %*[^\n]\n", &beginning, &ending, perms);
2027     if (rc == EOF) {
2028       break;
2029     }
2030     KMP_ASSERT(rc == 3 &&
2031                KMP_STRLEN(perms) == 4); // Make sure all fields are read.
2032 
2033     // Ending address is not included in the region, but beginning is.
2034     if ((addr >= beginning) && (addr < ending)) {
2035       perms[2] = 0; // 3th and 4th character does not matter.
2036       if (strcmp(perms, "rw") == 0) {
2037         // Memory we are looking for should be readable and writable.
2038         found = 1;
2039       }
2040       break;
2041     }
2042   }
2043 
2044   // Free resources.
2045   fclose(file);
2046   KMP_INTERNAL_FREE(name);
2047 #elif KMP_OS_FREEBSD
2048   char *buf;
2049   size_t lstsz;
2050   int mib[] = {CTL_KERN, KERN_PROC, KERN_PROC_VMMAP, getpid()};
2051   rc = sysctl(mib, 4, NULL, &lstsz, NULL, 0);
2052   if (rc < 0)
2053      return 0;
2054   // We pass from number of vm entry's semantic
2055   // to size of whole entry map list.
2056   lstsz = lstsz * 4 / 3;
2057   buf = reinterpret_cast<char *>(kmpc_malloc(lstsz));
2058   rc = sysctl(mib, 4, buf, &lstsz, NULL, 0);
2059   if (rc < 0) {
2060      kmpc_free(buf);
2061      return 0;
2062   }
2063 
2064   char *lw = buf;
2065   char *up = buf + lstsz;
2066 
2067   while (lw < up) {
2068       struct kinfo_vmentry *cur = reinterpret_cast<struct kinfo_vmentry *>(lw);
2069       size_t cursz = cur->kve_structsize;
2070       if (cursz == 0)
2071           break;
2072       void *start = reinterpret_cast<void *>(cur->kve_start);
2073       void *end = reinterpret_cast<void *>(cur->kve_end);
2074       // Readable/Writable addresses within current map entry
2075       if ((addr >= start) && (addr < end)) {
2076           if ((cur->kve_protection & KVME_PROT_READ) != 0 &&
2077               (cur->kve_protection & KVME_PROT_WRITE) != 0) {
2078               found = 1;
2079               break;
2080           }
2081       }
2082       lw += cursz;
2083   }
2084   kmpc_free(buf);
2085 
2086 #elif KMP_OS_DARWIN
2087 
2088   /* On OS X*, /proc pseudo filesystem is not available. Try to read memory
2089      using vm interface. */
2090 
2091   int buffer;
2092   vm_size_t count;
2093   rc = vm_read_overwrite(
2094       mach_task_self(), // Task to read memory of.
2095       (vm_address_t)(addr), // Address to read from.
2096       1, // Number of bytes to be read.
2097       (vm_address_t)(&buffer), // Address of buffer to save read bytes in.
2098       &count // Address of var to save number of read bytes in.
2099       );
2100   if (rc == 0) {
2101     // Memory successfully read.
2102     found = 1;
2103   }
2104 
2105 #elif KMP_OS_NETBSD
2106 
2107   int mib[5];
2108   mib[0] = CTL_VM;
2109   mib[1] = VM_PROC;
2110   mib[2] = VM_PROC_MAP;
2111   mib[3] = getpid();
2112   mib[4] = sizeof(struct kinfo_vmentry);
2113 
2114   size_t size;
2115   rc = sysctl(mib, __arraycount(mib), NULL, &size, NULL, 0);
2116   KMP_ASSERT(!rc);
2117   KMP_ASSERT(size);
2118 
2119   size = size * 4 / 3;
2120   struct kinfo_vmentry *kiv = (struct kinfo_vmentry *)KMP_INTERNAL_MALLOC(size);
2121   KMP_ASSERT(kiv);
2122 
2123   rc = sysctl(mib, __arraycount(mib), kiv, &size, NULL, 0);
2124   KMP_ASSERT(!rc);
2125   KMP_ASSERT(size);
2126 
2127   for (size_t i = 0; i < size; i++) {
2128     if (kiv[i].kve_start >= (uint64_t)addr &&
2129         kiv[i].kve_end <= (uint64_t)addr) {
2130       found = 1;
2131       break;
2132     }
2133   }
2134   KMP_INTERNAL_FREE(kiv);
2135 #elif KMP_OS_OPENBSD
2136 
2137   int mib[3];
2138   mib[0] = CTL_KERN;
2139   mib[1] = KERN_PROC_VMMAP;
2140   mib[2] = getpid();
2141 
2142   size_t size;
2143   uint64_t end;
2144   rc = sysctl(mib, 3, NULL, &size, NULL, 0);
2145   KMP_ASSERT(!rc);
2146   KMP_ASSERT(size);
2147   end = size;
2148 
2149   struct kinfo_vmentry kiv = {.kve_start = 0};
2150 
2151   while ((rc = sysctl(mib, 3, &kiv, &size, NULL, 0)) == 0) {
2152     KMP_ASSERT(size);
2153     if (kiv.kve_end == end)
2154       break;
2155 
2156     if (kiv.kve_start >= (uint64_t)addr && kiv.kve_end <= (uint64_t)addr) {
2157       found = 1;
2158       break;
2159     }
2160     kiv.kve_start += 1;
2161   }
2162 #elif KMP_OS_DRAGONFLY
2163 
2164   // FIXME(DragonFly): Implement this
2165   found = 1;
2166 
2167 #else
2168 
2169 #error "Unknown or unsupported OS"
2170 
2171 #endif
2172 
2173   return found;
2174 
2175 } // __kmp_is_address_mapped
2176 
2177 #ifdef USE_LOAD_BALANCE
2178 
2179 #if KMP_OS_DARWIN || KMP_OS_NETBSD
2180 
2181 // The function returns the rounded value of the system load average
2182 // during given time interval which depends on the value of
2183 // __kmp_load_balance_interval variable (default is 60 sec, other values
2184 // may be 300 sec or 900 sec).
2185 // It returns -1 in case of error.
2186 int __kmp_get_load_balance(int max) {
2187   double averages[3];
2188   int ret_avg = 0;
2189 
2190   int res = getloadavg(averages, 3);
2191 
2192   // Check __kmp_load_balance_interval to determine which of averages to use.
2193   // getloadavg() may return the number of samples less than requested that is
2194   // less than 3.
2195   if (__kmp_load_balance_interval < 180 && (res >= 1)) {
2196     ret_avg = averages[0]; // 1 min
2197   } else if ((__kmp_load_balance_interval >= 180 &&
2198               __kmp_load_balance_interval < 600) &&
2199              (res >= 2)) {
2200     ret_avg = averages[1]; // 5 min
2201   } else if ((__kmp_load_balance_interval >= 600) && (res == 3)) {
2202     ret_avg = averages[2]; // 15 min
2203   } else { // Error occurred
2204     return -1;
2205   }
2206 
2207   return ret_avg;
2208 }
2209 
2210 #else // Linux* OS
2211 
2212 // The function returns number of running (not sleeping) threads, or -1 in case
2213 // of error. Error could be reported if Linux* OS kernel too old (without
2214 // "/proc" support). Counting running threads stops if max running threads
2215 // encountered.
2216 int __kmp_get_load_balance(int max) {
2217   static int permanent_error = 0;
2218   static int glb_running_threads = 0; // Saved count of the running threads for
2219   // the thread balance algorithm
2220   static double glb_call_time = 0; /* Thread balance algorithm call time */
2221 
2222   int running_threads = 0; // Number of running threads in the system.
2223 
2224   DIR *proc_dir = NULL; // Handle of "/proc/" directory.
2225   struct dirent *proc_entry = NULL;
2226 
2227   kmp_str_buf_t task_path; // "/proc/<pid>/task/<tid>/" path.
2228   DIR *task_dir = NULL; // Handle of "/proc/<pid>/task/<tid>/" directory.
2229   struct dirent *task_entry = NULL;
2230   int task_path_fixed_len;
2231 
2232   kmp_str_buf_t stat_path; // "/proc/<pid>/task/<tid>/stat" path.
2233   int stat_file = -1;
2234   int stat_path_fixed_len;
2235 
2236   int total_processes = 0; // Total number of processes in system.
2237   int total_threads = 0; // Total number of threads in system.
2238 
2239   double call_time = 0.0;
2240 
2241   __kmp_str_buf_init(&task_path);
2242   __kmp_str_buf_init(&stat_path);
2243 
2244   __kmp_elapsed(&call_time);
2245 
2246   if (glb_call_time &&
2247       (call_time - glb_call_time < __kmp_load_balance_interval)) {
2248     running_threads = glb_running_threads;
2249     goto finish;
2250   }
2251 
2252   glb_call_time = call_time;
2253 
2254   // Do not spend time on scanning "/proc/" if we have a permanent error.
2255   if (permanent_error) {
2256     running_threads = -1;
2257     goto finish;
2258   }
2259 
2260   if (max <= 0) {
2261     max = INT_MAX;
2262   }
2263 
2264   // Open "/proc/" directory.
2265   proc_dir = opendir("/proc");
2266   if (proc_dir == NULL) {
2267     // Cannot open "/prroc/". Probably the kernel does not support it. Return an
2268     // error now and in subsequent calls.
2269     running_threads = -1;
2270     permanent_error = 1;
2271     goto finish;
2272   }
2273 
2274   // Initialize fixed part of task_path. This part will not change.
2275   __kmp_str_buf_cat(&task_path, "/proc/", 6);
2276   task_path_fixed_len = task_path.used; // Remember number of used characters.
2277 
2278   proc_entry = readdir(proc_dir);
2279   while (proc_entry != NULL) {
2280     // Proc entry is a directory and name starts with a digit. Assume it is a
2281     // process' directory.
2282     if (proc_entry->d_type == DT_DIR && isdigit(proc_entry->d_name[0])) {
2283 
2284       ++total_processes;
2285       // Make sure init process is the very first in "/proc", so we can replace
2286       // strcmp( proc_entry->d_name, "1" ) == 0 with simpler total_processes ==
2287       // 1. We are going to check that total_processes == 1 => d_name == "1" is
2288       // true (where "=>" is implication). Since C++ does not have => operator,
2289       // let us replace it with its equivalent: a => b == ! a || b.
2290       KMP_DEBUG_ASSERT(total_processes != 1 ||
2291                        strcmp(proc_entry->d_name, "1") == 0);
2292 
2293       // Construct task_path.
2294       task_path.used = task_path_fixed_len; // Reset task_path to "/proc/".
2295       __kmp_str_buf_cat(&task_path, proc_entry->d_name,
2296                         KMP_STRLEN(proc_entry->d_name));
2297       __kmp_str_buf_cat(&task_path, "/task", 5);
2298 
2299       task_dir = opendir(task_path.str);
2300       if (task_dir == NULL) {
2301         // Process can finish between reading "/proc/" directory entry and
2302         // opening process' "task/" directory. So, in general case we should not
2303         // complain, but have to skip this process and read the next one. But on
2304         // systems with no "task/" support we will spend lot of time to scan
2305         // "/proc/" tree again and again without any benefit. "init" process
2306         // (its pid is 1) should exist always, so, if we cannot open
2307         // "/proc/1/task/" directory, it means "task/" is not supported by
2308         // kernel. Report an error now and in the future.
2309         if (strcmp(proc_entry->d_name, "1") == 0) {
2310           running_threads = -1;
2311           permanent_error = 1;
2312           goto finish;
2313         }
2314       } else {
2315         // Construct fixed part of stat file path.
2316         __kmp_str_buf_clear(&stat_path);
2317         __kmp_str_buf_cat(&stat_path, task_path.str, task_path.used);
2318         __kmp_str_buf_cat(&stat_path, "/", 1);
2319         stat_path_fixed_len = stat_path.used;
2320 
2321         task_entry = readdir(task_dir);
2322         while (task_entry != NULL) {
2323           // It is a directory and name starts with a digit.
2324           if (proc_entry->d_type == DT_DIR && isdigit(task_entry->d_name[0])) {
2325             ++total_threads;
2326 
2327             // Construct complete stat file path. Easiest way would be:
2328             //  __kmp_str_buf_print( & stat_path, "%s/%s/stat", task_path.str,
2329             //  task_entry->d_name );
2330             // but seriae of __kmp_str_buf_cat works a bit faster.
2331             stat_path.used =
2332                 stat_path_fixed_len; // Reset stat path to its fixed part.
2333             __kmp_str_buf_cat(&stat_path, task_entry->d_name,
2334                               KMP_STRLEN(task_entry->d_name));
2335             __kmp_str_buf_cat(&stat_path, "/stat", 5);
2336 
2337             // Note: Low-level API (open/read/close) is used. High-level API
2338             // (fopen/fclose)  works ~ 30 % slower.
2339             stat_file = open(stat_path.str, O_RDONLY);
2340             if (stat_file == -1) {
2341               // We cannot report an error because task (thread) can terminate
2342               // just before reading this file.
2343             } else {
2344               /* Content of "stat" file looks like:
2345                  24285 (program) S ...
2346 
2347                  It is a single line (if program name does not include funny
2348                  symbols). First number is a thread id, then name of executable
2349                  file name in paretheses, then state of the thread. We need just
2350                  thread state.
2351 
2352                  Good news: Length of program name is 15 characters max. Longer
2353                  names are truncated.
2354 
2355                  Thus, we need rather short buffer: 15 chars for program name +
2356                  2 parenthesis, + 3 spaces + ~7 digits of pid = 37.
2357 
2358                  Bad news: Program name may contain special symbols like space,
2359                  closing parenthesis, or even new line. This makes parsing
2360                  "stat" file not 100 % reliable. In case of fanny program names
2361                  parsing may fail (report incorrect thread state).
2362 
2363                  Parsing "status" file looks more promissing (due to different
2364                  file structure and escaping special symbols) but reading and
2365                  parsing of "status" file works slower.
2366                   -- ln
2367               */
2368               char buffer[65];
2369               int len;
2370               len = read(stat_file, buffer, sizeof(buffer) - 1);
2371               if (len >= 0) {
2372                 buffer[len] = 0;
2373                 // Using scanf:
2374                 //     sscanf( buffer, "%*d (%*s) %c ", & state );
2375                 // looks very nice, but searching for a closing parenthesis
2376                 // works a bit faster.
2377                 char *close_parent = strstr(buffer, ") ");
2378                 if (close_parent != NULL) {
2379                   char state = *(close_parent + 2);
2380                   if (state == 'R') {
2381                     ++running_threads;
2382                     if (running_threads >= max) {
2383                       goto finish;
2384                     }
2385                   }
2386                 }
2387               }
2388               close(stat_file);
2389               stat_file = -1;
2390             }
2391           }
2392           task_entry = readdir(task_dir);
2393         }
2394         closedir(task_dir);
2395         task_dir = NULL;
2396       }
2397     }
2398     proc_entry = readdir(proc_dir);
2399   }
2400 
2401   // There _might_ be a timing hole where the thread executing this
2402   // code get skipped in the load balance, and running_threads is 0.
2403   // Assert in the debug builds only!!!
2404   KMP_DEBUG_ASSERT(running_threads > 0);
2405   if (running_threads <= 0) {
2406     running_threads = 1;
2407   }
2408 
2409 finish: // Clean up and exit.
2410   if (proc_dir != NULL) {
2411     closedir(proc_dir);
2412   }
2413   __kmp_str_buf_free(&task_path);
2414   if (task_dir != NULL) {
2415     closedir(task_dir);
2416   }
2417   __kmp_str_buf_free(&stat_path);
2418   if (stat_file != -1) {
2419     close(stat_file);
2420   }
2421 
2422   glb_running_threads = running_threads;
2423 
2424   return running_threads;
2425 
2426 } // __kmp_get_load_balance
2427 
2428 #endif // KMP_OS_DARWIN
2429 
2430 #endif // USE_LOAD_BALANCE
2431 
2432 #if !(KMP_ARCH_X86 || KMP_ARCH_X86_64 || KMP_MIC ||                            \
2433       ((KMP_OS_LINUX || KMP_OS_DARWIN) && KMP_ARCH_AARCH64) ||                 \
2434       KMP_ARCH_PPC64 || KMP_ARCH_RISCV64)
2435 
2436 // we really only need the case with 1 argument, because CLANG always build
2437 // a struct of pointers to shared variables referenced in the outlined function
2438 int __kmp_invoke_microtask(microtask_t pkfn, int gtid, int tid, int argc,
2439                            void *p_argv[]
2440 #if OMPT_SUPPORT
2441                            ,
2442                            void **exit_frame_ptr
2443 #endif
2444                            ) {
2445 #if OMPT_SUPPORT
2446   *exit_frame_ptr = OMPT_GET_FRAME_ADDRESS(0);
2447 #endif
2448 
2449   switch (argc) {
2450   default:
2451     fprintf(stderr, "Too many args to microtask: %d!\n", argc);
2452     fflush(stderr);
2453     exit(-1);
2454   case 0:
2455     (*pkfn)(&gtid, &tid);
2456     break;
2457   case 1:
2458     (*pkfn)(&gtid, &tid, p_argv[0]);
2459     break;
2460   case 2:
2461     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1]);
2462     break;
2463   case 3:
2464     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2]);
2465     break;
2466   case 4:
2467     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3]);
2468     break;
2469   case 5:
2470     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4]);
2471     break;
2472   case 6:
2473     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2474             p_argv[5]);
2475     break;
2476   case 7:
2477     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2478             p_argv[5], p_argv[6]);
2479     break;
2480   case 8:
2481     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2482             p_argv[5], p_argv[6], p_argv[7]);
2483     break;
2484   case 9:
2485     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2486             p_argv[5], p_argv[6], p_argv[7], p_argv[8]);
2487     break;
2488   case 10:
2489     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2490             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9]);
2491     break;
2492   case 11:
2493     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2494             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10]);
2495     break;
2496   case 12:
2497     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2498             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2499             p_argv[11]);
2500     break;
2501   case 13:
2502     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2503             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2504             p_argv[11], p_argv[12]);
2505     break;
2506   case 14:
2507     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2508             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2509             p_argv[11], p_argv[12], p_argv[13]);
2510     break;
2511   case 15:
2512     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2513             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2514             p_argv[11], p_argv[12], p_argv[13], p_argv[14]);
2515     break;
2516   }
2517 
2518   return 1;
2519 }
2520 
2521 #endif
2522 
2523 // end of file //
2524