1 /*
2  * z_Linux_util.cpp -- platform specific routines.
3  */
4 
5 
6 //===----------------------------------------------------------------------===//
7 //
8 //                     The LLVM Compiler Infrastructure
9 //
10 // This file is dual licensed under the MIT and the University of Illinois Open
11 // Source Licenses. See LICENSE.txt for details.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 
16 #include "kmp.h"
17 #include "kmp_affinity.h"
18 #include "kmp_i18n.h"
19 #include "kmp_io.h"
20 #include "kmp_itt.h"
21 #include "kmp_lock.h"
22 #include "kmp_stats.h"
23 #include "kmp_str.h"
24 #include "kmp_wait_release.h"
25 #include "kmp_wrapper_getpid.h"
26 
27 #if !KMP_OS_FREEBSD && !KMP_OS_NETBSD
28 #include <alloca.h>
29 #endif
30 #include <math.h> // HUGE_VAL.
31 #include <sys/resource.h>
32 #include <sys/syscall.h>
33 #include <sys/time.h>
34 #include <sys/times.h>
35 #include <unistd.h>
36 
37 #if KMP_OS_LINUX && !KMP_OS_CNK
38 #include <sys/sysinfo.h>
39 #if KMP_USE_FUTEX
40 // We should really include <futex.h>, but that causes compatibility problems on
41 // different Linux* OS distributions that either require that you include (or
42 // break when you try to include) <pci/types.h>. Since all we need is the two
43 // macros below (which are part of the kernel ABI, so can't change) we just
44 // define the constants here and don't include <futex.h>
45 #ifndef FUTEX_WAIT
46 #define FUTEX_WAIT 0
47 #endif
48 #ifndef FUTEX_WAKE
49 #define FUTEX_WAKE 1
50 #endif
51 #endif
52 #elif KMP_OS_DARWIN
53 #include <mach/mach.h>
54 #include <sys/sysctl.h>
55 #elif KMP_OS_FREEBSD
56 #include <pthread_np.h>
57 #endif
58 
59 #include <ctype.h>
60 #include <dirent.h>
61 #include <fcntl.h>
62 
63 #include "tsan_annotations.h"
64 
65 struct kmp_sys_timer {
66   struct timespec start;
67 };
68 
69 // Convert timespec to nanoseconds.
70 #define TS2NS(timespec) (((timespec).tv_sec * 1e9) + (timespec).tv_nsec)
71 
72 static struct kmp_sys_timer __kmp_sys_timer_data;
73 
74 #if KMP_HANDLE_SIGNALS
75 typedef void (*sig_func_t)(int);
76 STATIC_EFI2_WORKAROUND struct sigaction __kmp_sighldrs[NSIG];
77 static sigset_t __kmp_sigset;
78 #endif
79 
80 static int __kmp_init_runtime = FALSE;
81 
82 static int __kmp_fork_count = 0;
83 
84 static pthread_condattr_t __kmp_suspend_cond_attr;
85 static pthread_mutexattr_t __kmp_suspend_mutex_attr;
86 
87 static kmp_cond_align_t __kmp_wait_cv;
88 static kmp_mutex_align_t __kmp_wait_mx;
89 
90 kmp_uint64 __kmp_ticks_per_msec = 1000000;
91 
92 #ifdef DEBUG_SUSPEND
93 static void __kmp_print_cond(char *buffer, kmp_cond_align_t *cond) {
94   KMP_SNPRINTF(buffer, 128, "(cond (lock (%ld, %d)), (descr (%p)))",
95                cond->c_cond.__c_lock.__status, cond->c_cond.__c_lock.__spinlock,
96                cond->c_cond.__c_waiting);
97 }
98 #endif
99 
100 #if (KMP_OS_LINUX && KMP_AFFINITY_SUPPORTED)
101 
102 /* Affinity support */
103 
104 void __kmp_affinity_bind_thread(int which) {
105   KMP_ASSERT2(KMP_AFFINITY_CAPABLE(),
106               "Illegal set affinity operation when not capable");
107 
108   kmp_affin_mask_t *mask;
109   KMP_CPU_ALLOC_ON_STACK(mask);
110   KMP_CPU_ZERO(mask);
111   KMP_CPU_SET(which, mask);
112   __kmp_set_system_affinity(mask, TRUE);
113   KMP_CPU_FREE_FROM_STACK(mask);
114 }
115 
116 /* Determine if we can access affinity functionality on this version of
117  * Linux* OS by checking __NR_sched_{get,set}affinity system calls, and set
118  * __kmp_affin_mask_size to the appropriate value (0 means not capable). */
119 void __kmp_affinity_determine_capable(const char *env_var) {
120 // Check and see if the OS supports thread affinity.
121 
122 #define KMP_CPU_SET_SIZE_LIMIT (1024 * 1024)
123 
124   int gCode;
125   int sCode;
126   unsigned char *buf;
127   buf = (unsigned char *)KMP_INTERNAL_MALLOC(KMP_CPU_SET_SIZE_LIMIT);
128 
129   // If Linux* OS:
130   // If the syscall fails or returns a suggestion for the size,
131   // then we don't have to search for an appropriate size.
132   gCode = syscall(__NR_sched_getaffinity, 0, KMP_CPU_SET_SIZE_LIMIT, buf);
133   KA_TRACE(30, ("__kmp_affinity_determine_capable: "
134                 "initial getaffinity call returned %d errno = %d\n",
135                 gCode, errno));
136 
137   // if ((gCode < 0) && (errno == ENOSYS))
138   if (gCode < 0) {
139     // System call not supported
140     if (__kmp_affinity_verbose ||
141         (__kmp_affinity_warnings && (__kmp_affinity_type != affinity_none) &&
142          (__kmp_affinity_type != affinity_default) &&
143          (__kmp_affinity_type != affinity_disabled))) {
144       int error = errno;
145       kmp_msg_t err_code = KMP_ERR(error);
146       __kmp_msg(kmp_ms_warning, KMP_MSG(GetAffSysCallNotSupported, env_var),
147                 err_code, __kmp_msg_null);
148       if (__kmp_generate_warnings == kmp_warnings_off) {
149         __kmp_str_free(&err_code.str);
150       }
151     }
152     KMP_AFFINITY_DISABLE();
153     KMP_INTERNAL_FREE(buf);
154     return;
155   }
156   if (gCode > 0) { // Linux* OS only
157     // The optimal situation: the OS returns the size of the buffer it expects.
158     //
159     // A verification of correct behavior is that Isetaffinity on a NULL
160     // buffer with the same size fails with errno set to EFAULT.
161     sCode = syscall(__NR_sched_setaffinity, 0, gCode, NULL);
162     KA_TRACE(30, ("__kmp_affinity_determine_capable: "
163                   "setaffinity for mask size %d returned %d errno = %d\n",
164                   gCode, sCode, errno));
165     if (sCode < 0) {
166       if (errno == ENOSYS) {
167         if (__kmp_affinity_verbose ||
168             (__kmp_affinity_warnings &&
169              (__kmp_affinity_type != affinity_none) &&
170              (__kmp_affinity_type != affinity_default) &&
171              (__kmp_affinity_type != affinity_disabled))) {
172           int error = errno;
173           kmp_msg_t err_code = KMP_ERR(error);
174           __kmp_msg(kmp_ms_warning, KMP_MSG(SetAffSysCallNotSupported, env_var),
175                     err_code, __kmp_msg_null);
176           if (__kmp_generate_warnings == kmp_warnings_off) {
177             __kmp_str_free(&err_code.str);
178           }
179         }
180         KMP_AFFINITY_DISABLE();
181         KMP_INTERNAL_FREE(buf);
182       }
183       if (errno == EFAULT) {
184         KMP_AFFINITY_ENABLE(gCode);
185         KA_TRACE(10, ("__kmp_affinity_determine_capable: "
186                       "affinity supported (mask size %d)\n",
187                       (int)__kmp_affin_mask_size));
188         KMP_INTERNAL_FREE(buf);
189         return;
190       }
191     }
192   }
193 
194   // Call the getaffinity system call repeatedly with increasing set sizes
195   // until we succeed, or reach an upper bound on the search.
196   KA_TRACE(30, ("__kmp_affinity_determine_capable: "
197                 "searching for proper set size\n"));
198   int size;
199   for (size = 1; size <= KMP_CPU_SET_SIZE_LIMIT; size *= 2) {
200     gCode = syscall(__NR_sched_getaffinity, 0, size, buf);
201     KA_TRACE(30, ("__kmp_affinity_determine_capable: "
202                   "getaffinity for mask size %d returned %d errno = %d\n",
203                   size, gCode, errno));
204 
205     if (gCode < 0) {
206       if (errno == ENOSYS) {
207         // We shouldn't get here
208         KA_TRACE(30, ("__kmp_affinity_determine_capable: "
209                       "inconsistent OS call behavior: errno == ENOSYS for mask "
210                       "size %d\n",
211                       size));
212         if (__kmp_affinity_verbose ||
213             (__kmp_affinity_warnings &&
214              (__kmp_affinity_type != affinity_none) &&
215              (__kmp_affinity_type != affinity_default) &&
216              (__kmp_affinity_type != affinity_disabled))) {
217           int error = errno;
218           kmp_msg_t err_code = KMP_ERR(error);
219           __kmp_msg(kmp_ms_warning, KMP_MSG(GetAffSysCallNotSupported, env_var),
220                     err_code, __kmp_msg_null);
221           if (__kmp_generate_warnings == kmp_warnings_off) {
222             __kmp_str_free(&err_code.str);
223           }
224         }
225         KMP_AFFINITY_DISABLE();
226         KMP_INTERNAL_FREE(buf);
227         return;
228       }
229       continue;
230     }
231 
232     sCode = syscall(__NR_sched_setaffinity, 0, gCode, NULL);
233     KA_TRACE(30, ("__kmp_affinity_determine_capable: "
234                   "setaffinity for mask size %d returned %d errno = %d\n",
235                   gCode, sCode, errno));
236     if (sCode < 0) {
237       if (errno == ENOSYS) { // Linux* OS only
238         // We shouldn't get here
239         KA_TRACE(30, ("__kmp_affinity_determine_capable: "
240                       "inconsistent OS call behavior: errno == ENOSYS for mask "
241                       "size %d\n",
242                       size));
243         if (__kmp_affinity_verbose ||
244             (__kmp_affinity_warnings &&
245              (__kmp_affinity_type != affinity_none) &&
246              (__kmp_affinity_type != affinity_default) &&
247              (__kmp_affinity_type != affinity_disabled))) {
248           int error = errno;
249           kmp_msg_t err_code = KMP_ERR(error);
250           __kmp_msg(kmp_ms_warning, KMP_MSG(SetAffSysCallNotSupported, env_var),
251                     err_code, __kmp_msg_null);
252           if (__kmp_generate_warnings == kmp_warnings_off) {
253             __kmp_str_free(&err_code.str);
254           }
255         }
256         KMP_AFFINITY_DISABLE();
257         KMP_INTERNAL_FREE(buf);
258         return;
259       }
260       if (errno == EFAULT) {
261         KMP_AFFINITY_ENABLE(gCode);
262         KA_TRACE(10, ("__kmp_affinity_determine_capable: "
263                       "affinity supported (mask size %d)\n",
264                       (int)__kmp_affin_mask_size));
265         KMP_INTERNAL_FREE(buf);
266         return;
267       }
268     }
269   }
270   // save uncaught error code
271   // int error = errno;
272   KMP_INTERNAL_FREE(buf);
273   // restore uncaught error code, will be printed at the next KMP_WARNING below
274   // errno = error;
275 
276   // Affinity is not supported
277   KMP_AFFINITY_DISABLE();
278   KA_TRACE(10, ("__kmp_affinity_determine_capable: "
279                 "cannot determine mask size - affinity not supported\n"));
280   if (__kmp_affinity_verbose ||
281       (__kmp_affinity_warnings && (__kmp_affinity_type != affinity_none) &&
282        (__kmp_affinity_type != affinity_default) &&
283        (__kmp_affinity_type != affinity_disabled))) {
284     KMP_WARNING(AffCantGetMaskSize, env_var);
285   }
286 }
287 
288 #endif // KMP_OS_LINUX && KMP_AFFINITY_SUPPORTED
289 
290 #if KMP_USE_FUTEX
291 
292 int __kmp_futex_determine_capable() {
293   int loc = 0;
294   int rc = syscall(__NR_futex, &loc, FUTEX_WAKE, 1, NULL, NULL, 0);
295   int retval = (rc == 0) || (errno != ENOSYS);
296 
297   KA_TRACE(10,
298            ("__kmp_futex_determine_capable: rc = %d errno = %d\n", rc, errno));
299   KA_TRACE(10, ("__kmp_futex_determine_capable: futex syscall%s supported\n",
300                 retval ? "" : " not"));
301 
302   return retval;
303 }
304 
305 #endif // KMP_USE_FUTEX
306 
307 #if (KMP_ARCH_X86 || KMP_ARCH_X86_64) && (!KMP_ASM_INTRINS)
308 /* Only 32-bit "add-exchange" instruction on IA-32 architecture causes us to
309    use compare_and_store for these routines */
310 
311 kmp_int8 __kmp_test_then_or8(volatile kmp_int8 *p, kmp_int8 d) {
312   kmp_int8 old_value, new_value;
313 
314   old_value = TCR_1(*p);
315   new_value = old_value | d;
316 
317   while (!KMP_COMPARE_AND_STORE_REL8(p, old_value, new_value)) {
318     KMP_CPU_PAUSE();
319     old_value = TCR_1(*p);
320     new_value = old_value | d;
321   }
322   return old_value;
323 }
324 
325 kmp_int8 __kmp_test_then_and8(volatile kmp_int8 *p, kmp_int8 d) {
326   kmp_int8 old_value, new_value;
327 
328   old_value = TCR_1(*p);
329   new_value = old_value & d;
330 
331   while (!KMP_COMPARE_AND_STORE_REL8(p, old_value, new_value)) {
332     KMP_CPU_PAUSE();
333     old_value = TCR_1(*p);
334     new_value = old_value & d;
335   }
336   return old_value;
337 }
338 
339 kmp_uint32 __kmp_test_then_or32(volatile kmp_uint32 *p, kmp_uint32 d) {
340   kmp_uint32 old_value, new_value;
341 
342   old_value = TCR_4(*p);
343   new_value = old_value | d;
344 
345   while (!KMP_COMPARE_AND_STORE_REL32(p, old_value, new_value)) {
346     KMP_CPU_PAUSE();
347     old_value = TCR_4(*p);
348     new_value = old_value | d;
349   }
350   return old_value;
351 }
352 
353 kmp_uint32 __kmp_test_then_and32(volatile kmp_uint32 *p, kmp_uint32 d) {
354   kmp_uint32 old_value, new_value;
355 
356   old_value = TCR_4(*p);
357   new_value = old_value & d;
358 
359   while (!KMP_COMPARE_AND_STORE_REL32(p, old_value, new_value)) {
360     KMP_CPU_PAUSE();
361     old_value = TCR_4(*p);
362     new_value = old_value & d;
363   }
364   return old_value;
365 }
366 
367 #if KMP_ARCH_X86
368 kmp_int8 __kmp_test_then_add8(volatile kmp_int8 *p, kmp_int8 d) {
369   kmp_int8 old_value, new_value;
370 
371   old_value = TCR_1(*p);
372   new_value = old_value + d;
373 
374   while (!KMP_COMPARE_AND_STORE_REL8(p, old_value, new_value)) {
375     KMP_CPU_PAUSE();
376     old_value = TCR_1(*p);
377     new_value = old_value + d;
378   }
379   return old_value;
380 }
381 
382 kmp_int64 __kmp_test_then_add64(volatile kmp_int64 *p, kmp_int64 d) {
383   kmp_int64 old_value, new_value;
384 
385   old_value = TCR_8(*p);
386   new_value = old_value + d;
387 
388   while (!KMP_COMPARE_AND_STORE_REL64(p, old_value, new_value)) {
389     KMP_CPU_PAUSE();
390     old_value = TCR_8(*p);
391     new_value = old_value + d;
392   }
393   return old_value;
394 }
395 #endif /* KMP_ARCH_X86 */
396 
397 kmp_uint64 __kmp_test_then_or64(volatile kmp_uint64 *p, kmp_uint64 d) {
398   kmp_uint64 old_value, new_value;
399 
400   old_value = TCR_8(*p);
401   new_value = old_value | d;
402   while (!KMP_COMPARE_AND_STORE_REL64(p, old_value, new_value)) {
403     KMP_CPU_PAUSE();
404     old_value = TCR_8(*p);
405     new_value = old_value | d;
406   }
407   return old_value;
408 }
409 
410 kmp_uint64 __kmp_test_then_and64(volatile kmp_uint64 *p, kmp_uint64 d) {
411   kmp_uint64 old_value, new_value;
412 
413   old_value = TCR_8(*p);
414   new_value = old_value & d;
415   while (!KMP_COMPARE_AND_STORE_REL64(p, old_value, new_value)) {
416     KMP_CPU_PAUSE();
417     old_value = TCR_8(*p);
418     new_value = old_value & d;
419   }
420   return old_value;
421 }
422 
423 #endif /* (KMP_ARCH_X86 || KMP_ARCH_X86_64) && (! KMP_ASM_INTRINS) */
424 
425 void __kmp_terminate_thread(int gtid) {
426   int status;
427   kmp_info_t *th = __kmp_threads[gtid];
428 
429   if (!th)
430     return;
431 
432 #ifdef KMP_CANCEL_THREADS
433   KA_TRACE(10, ("__kmp_terminate_thread: kill (%d)\n", gtid));
434   status = pthread_cancel(th->th.th_info.ds.ds_thread);
435   if (status != 0 && status != ESRCH) {
436     __kmp_msg(kmp_ms_fatal, KMP_MSG(CantTerminateWorkerThread), KMP_ERR(status),
437               __kmp_msg_null);
438   }; // if
439 #endif
440   __kmp_yield(TRUE);
441 } //
442 
443 /* Set thread stack info according to values returned by pthread_getattr_np().
444    If values are unreasonable, assume call failed and use incremental stack
445    refinement method instead. Returns TRUE if the stack parameters could be
446    determined exactly, FALSE if incremental refinement is necessary. */
447 static kmp_int32 __kmp_set_stack_info(int gtid, kmp_info_t *th) {
448   int stack_data;
449 #if KMP_OS_LINUX || KMP_OS_FREEBSD || KMP_OS_NETBSD
450   /* Linux* OS only -- no pthread_getattr_np support on OS X* */
451   pthread_attr_t attr;
452   int status;
453   size_t size = 0;
454   void *addr = 0;
455 
456   /* Always do incremental stack refinement for ubermaster threads since the
457      initial thread stack range can be reduced by sibling thread creation so
458      pthread_attr_getstack may cause thread gtid aliasing */
459   if (!KMP_UBER_GTID(gtid)) {
460 
461     /* Fetch the real thread attributes */
462     status = pthread_attr_init(&attr);
463     KMP_CHECK_SYSFAIL("pthread_attr_init", status);
464 #if KMP_OS_FREEBSD || KMP_OS_NETBSD
465     status = pthread_attr_get_np(pthread_self(), &attr);
466     KMP_CHECK_SYSFAIL("pthread_attr_get_np", status);
467 #else
468     status = pthread_getattr_np(pthread_self(), &attr);
469     KMP_CHECK_SYSFAIL("pthread_getattr_np", status);
470 #endif
471     status = pthread_attr_getstack(&attr, &addr, &size);
472     KMP_CHECK_SYSFAIL("pthread_attr_getstack", status);
473     KA_TRACE(60,
474              ("__kmp_set_stack_info: T#%d pthread_attr_getstack returned size:"
475               " %lu, low addr: %p\n",
476               gtid, size, addr));
477     status = pthread_attr_destroy(&attr);
478     KMP_CHECK_SYSFAIL("pthread_attr_destroy", status);
479   }
480 
481   if (size != 0 && addr != 0) { // was stack parameter determination successful?
482     /* Store the correct base and size */
483     TCW_PTR(th->th.th_info.ds.ds_stackbase, (((char *)addr) + size));
484     TCW_PTR(th->th.th_info.ds.ds_stacksize, size);
485     TCW_4(th->th.th_info.ds.ds_stackgrow, FALSE);
486     return TRUE;
487   }
488 #endif /* KMP_OS_LINUX || KMP_OS_FREEBSD || KMP_OS_NETBSD */
489   /* Use incremental refinement starting from initial conservative estimate */
490   TCW_PTR(th->th.th_info.ds.ds_stacksize, 0);
491   TCW_PTR(th->th.th_info.ds.ds_stackbase, &stack_data);
492   TCW_4(th->th.th_info.ds.ds_stackgrow, TRUE);
493   return FALSE;
494 }
495 
496 static void *__kmp_launch_worker(void *thr) {
497   int status, old_type, old_state;
498 #ifdef KMP_BLOCK_SIGNALS
499   sigset_t new_set, old_set;
500 #endif /* KMP_BLOCK_SIGNALS */
501   void *exit_val;
502 #if KMP_OS_LINUX || KMP_OS_FREEBSD || KMP_OS_NETBSD
503   void *volatile padding = 0;
504 #endif
505   int gtid;
506 
507   gtid = ((kmp_info_t *)thr)->th.th_info.ds.ds_gtid;
508   __kmp_gtid_set_specific(gtid);
509 #ifdef KMP_TDATA_GTID
510   __kmp_gtid = gtid;
511 #endif
512 #if KMP_STATS_ENABLED
513   // set __thread local index to point to thread-specific stats
514   __kmp_stats_thread_ptr = ((kmp_info_t *)thr)->th.th_stats;
515   KMP_START_EXPLICIT_TIMER(OMP_worker_thread_life);
516   KMP_SET_THREAD_STATE(IDLE);
517   KMP_INIT_PARTITIONED_TIMERS(OMP_idle);
518 #endif
519 
520 #if USE_ITT_BUILD
521   __kmp_itt_thread_name(gtid);
522 #endif /* USE_ITT_BUILD */
523 
524 #if KMP_AFFINITY_SUPPORTED
525   __kmp_affinity_set_init_mask(gtid, FALSE);
526 #endif
527 
528 #ifdef KMP_CANCEL_THREADS
529   status = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old_type);
530   KMP_CHECK_SYSFAIL("pthread_setcanceltype", status);
531   // josh todo: isn't PTHREAD_CANCEL_ENABLE default for newly-created threads?
532   status = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_state);
533   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
534 #endif
535 
536 #if KMP_ARCH_X86 || KMP_ARCH_X86_64
537   // Set FP control regs to be a copy of the parallel initialization thread's.
538   __kmp_clear_x87_fpu_status_word();
539   __kmp_load_x87_fpu_control_word(&__kmp_init_x87_fpu_control_word);
540   __kmp_load_mxcsr(&__kmp_init_mxcsr);
541 #endif /* KMP_ARCH_X86 || KMP_ARCH_X86_64 */
542 
543 #ifdef KMP_BLOCK_SIGNALS
544   status = sigfillset(&new_set);
545   KMP_CHECK_SYSFAIL_ERRNO("sigfillset", status);
546   status = pthread_sigmask(SIG_BLOCK, &new_set, &old_set);
547   KMP_CHECK_SYSFAIL("pthread_sigmask", status);
548 #endif /* KMP_BLOCK_SIGNALS */
549 
550 #if KMP_OS_LINUX || KMP_OS_FREEBSD || KMP_OS_NETBSD
551   if (__kmp_stkoffset > 0 && gtid > 0) {
552     padding = KMP_ALLOCA(gtid * __kmp_stkoffset);
553   }
554 #endif
555 
556   KMP_MB();
557   __kmp_set_stack_info(gtid, (kmp_info_t *)thr);
558 
559   __kmp_check_stack_overlap((kmp_info_t *)thr);
560 
561   exit_val = __kmp_launch_thread((kmp_info_t *)thr);
562 
563 #ifdef KMP_BLOCK_SIGNALS
564   status = pthread_sigmask(SIG_SETMASK, &old_set, NULL);
565   KMP_CHECK_SYSFAIL("pthread_sigmask", status);
566 #endif /* KMP_BLOCK_SIGNALS */
567 
568   return exit_val;
569 }
570 
571 #if KMP_USE_MONITOR
572 /* The monitor thread controls all of the threads in the complex */
573 
574 static void *__kmp_launch_monitor(void *thr) {
575   int status, old_type, old_state;
576 #ifdef KMP_BLOCK_SIGNALS
577   sigset_t new_set;
578 #endif /* KMP_BLOCK_SIGNALS */
579   struct timespec interval;
580   int yield_count;
581   int yield_cycles = 0;
582 
583   KMP_MB(); /* Flush all pending memory write invalidates.  */
584 
585   KA_TRACE(10, ("__kmp_launch_monitor: #1 launched\n"));
586 
587   /* register us as the monitor thread */
588   __kmp_gtid_set_specific(KMP_GTID_MONITOR);
589 #ifdef KMP_TDATA_GTID
590   __kmp_gtid = KMP_GTID_MONITOR;
591 #endif
592 
593   KMP_MB();
594 
595 #if USE_ITT_BUILD
596   // Instruct Intel(R) Threading Tools to ignore monitor thread.
597   __kmp_itt_thread_ignore();
598 #endif /* USE_ITT_BUILD */
599 
600   __kmp_set_stack_info(((kmp_info_t *)thr)->th.th_info.ds.ds_gtid,
601                        (kmp_info_t *)thr);
602 
603   __kmp_check_stack_overlap((kmp_info_t *)thr);
604 
605 #ifdef KMP_CANCEL_THREADS
606   status = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old_type);
607   KMP_CHECK_SYSFAIL("pthread_setcanceltype", status);
608   // josh todo: isn't PTHREAD_CANCEL_ENABLE default for newly-created threads?
609   status = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_state);
610   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
611 #endif
612 
613 #if KMP_REAL_TIME_FIX
614   // This is a potential fix which allows application with real-time scheduling
615   // policy work. However, decision about the fix is not made yet, so it is
616   // disabled by default.
617   { // Are program started with real-time scheduling policy?
618     int sched = sched_getscheduler(0);
619     if (sched == SCHED_FIFO || sched == SCHED_RR) {
620       // Yes, we are a part of real-time application. Try to increase the
621       // priority of the monitor.
622       struct sched_param param;
623       int max_priority = sched_get_priority_max(sched);
624       int rc;
625       KMP_WARNING(RealTimeSchedNotSupported);
626       sched_getparam(0, &param);
627       if (param.sched_priority < max_priority) {
628         param.sched_priority += 1;
629         rc = sched_setscheduler(0, sched, &param);
630         if (rc != 0) {
631           int error = errno;
632           kmp_msg_t err_code = KMP_ERR(error);
633           __kmp_msg(kmp_ms_warning, KMP_MSG(CantChangeMonitorPriority),
634                     err_code, KMP_MSG(MonitorWillStarve), __kmp_msg_null);
635           if (__kmp_generate_warnings == kmp_warnings_off) {
636             __kmp_str_free(&err_code.str);
637           }
638         }; // if
639       } else {
640         // We cannot abort here, because number of CPUs may be enough for all
641         // the threads, including the monitor thread, so application could
642         // potentially work...
643         __kmp_msg(kmp_ms_warning, KMP_MSG(RunningAtMaxPriority),
644                   KMP_MSG(MonitorWillStarve), KMP_HNT(RunningAtMaxPriority),
645                   __kmp_msg_null);
646       }; // if
647     }; // if
648     // AC: free thread that waits for monitor started
649     TCW_4(__kmp_global.g.g_time.dt.t_value, 0);
650   }
651 #endif // KMP_REAL_TIME_FIX
652 
653   KMP_MB(); /* Flush all pending memory write invalidates.  */
654 
655   if (__kmp_monitor_wakeups == 1) {
656     interval.tv_sec = 1;
657     interval.tv_nsec = 0;
658   } else {
659     interval.tv_sec = 0;
660     interval.tv_nsec = (KMP_NSEC_PER_SEC / __kmp_monitor_wakeups);
661   }
662 
663   KA_TRACE(10, ("__kmp_launch_monitor: #2 monitor\n"));
664 
665   if (__kmp_yield_cycle) {
666     __kmp_yielding_on = 0; /* Start out with yielding shut off */
667     yield_count = __kmp_yield_off_count;
668   } else {
669     __kmp_yielding_on = 1; /* Yielding is on permanently */
670   }
671 
672   while (!TCR_4(__kmp_global.g.g_done)) {
673     struct timespec now;
674     struct timeval tval;
675 
676     /*  This thread monitors the state of the system */
677 
678     KA_TRACE(15, ("__kmp_launch_monitor: update\n"));
679 
680     status = gettimeofday(&tval, NULL);
681     KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
682     TIMEVAL_TO_TIMESPEC(&tval, &now);
683 
684     now.tv_sec += interval.tv_sec;
685     now.tv_nsec += interval.tv_nsec;
686 
687     if (now.tv_nsec >= KMP_NSEC_PER_SEC) {
688       now.tv_sec += 1;
689       now.tv_nsec -= KMP_NSEC_PER_SEC;
690     }
691 
692     status = pthread_mutex_lock(&__kmp_wait_mx.m_mutex);
693     KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
694     // AC: the monitor should not fall asleep if g_done has been set
695     if (!TCR_4(__kmp_global.g.g_done)) { // check once more under mutex
696       status = pthread_cond_timedwait(&__kmp_wait_cv.c_cond,
697                                       &__kmp_wait_mx.m_mutex, &now);
698       if (status != 0) {
699         if (status != ETIMEDOUT && status != EINTR) {
700           KMP_SYSFAIL("pthread_cond_timedwait", status);
701         };
702       };
703     };
704     status = pthread_mutex_unlock(&__kmp_wait_mx.m_mutex);
705     KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
706 
707     if (__kmp_yield_cycle) {
708       yield_cycles++;
709       if ((yield_cycles % yield_count) == 0) {
710         if (__kmp_yielding_on) {
711           __kmp_yielding_on = 0; /* Turn it off now */
712           yield_count = __kmp_yield_off_count;
713         } else {
714           __kmp_yielding_on = 1; /* Turn it on now */
715           yield_count = __kmp_yield_on_count;
716         }
717         yield_cycles = 0;
718       }
719     } else {
720       __kmp_yielding_on = 1;
721     }
722 
723     TCW_4(__kmp_global.g.g_time.dt.t_value,
724           TCR_4(__kmp_global.g.g_time.dt.t_value) + 1);
725 
726     KMP_MB(); /* Flush all pending memory write invalidates.  */
727   }
728 
729   KA_TRACE(10, ("__kmp_launch_monitor: #3 cleanup\n"));
730 
731 #ifdef KMP_BLOCK_SIGNALS
732   status = sigfillset(&new_set);
733   KMP_CHECK_SYSFAIL_ERRNO("sigfillset", status);
734   status = pthread_sigmask(SIG_UNBLOCK, &new_set, NULL);
735   KMP_CHECK_SYSFAIL("pthread_sigmask", status);
736 #endif /* KMP_BLOCK_SIGNALS */
737 
738   KA_TRACE(10, ("__kmp_launch_monitor: #4 finished\n"));
739 
740   if (__kmp_global.g.g_abort != 0) {
741     /* now we need to terminate the worker threads  */
742     /* the value of t_abort is the signal we caught */
743 
744     int gtid;
745 
746     KA_TRACE(10, ("__kmp_launch_monitor: #5 terminate sig=%d\n",
747                   __kmp_global.g.g_abort));
748 
749     /* terminate the OpenMP worker threads */
750     /* TODO this is not valid for sibling threads!!
751      * the uber master might not be 0 anymore.. */
752     for (gtid = 1; gtid < __kmp_threads_capacity; ++gtid)
753       __kmp_terminate_thread(gtid);
754 
755     __kmp_cleanup();
756 
757     KA_TRACE(10, ("__kmp_launch_monitor: #6 raise sig=%d\n",
758                   __kmp_global.g.g_abort));
759 
760     if (__kmp_global.g.g_abort > 0)
761       raise(__kmp_global.g.g_abort);
762   }
763 
764   KA_TRACE(10, ("__kmp_launch_monitor: #7 exit\n"));
765 
766   return thr;
767 }
768 #endif // KMP_USE_MONITOR
769 
770 void __kmp_create_worker(int gtid, kmp_info_t *th, size_t stack_size) {
771   pthread_t handle;
772   pthread_attr_t thread_attr;
773   int status;
774 
775   th->th.th_info.ds.ds_gtid = gtid;
776 
777 #if KMP_STATS_ENABLED
778   // sets up worker thread stats
779   __kmp_acquire_tas_lock(&__kmp_stats_lock, gtid);
780 
781   // th->th.th_stats is used to transfer thread-specific stats-pointer to
782   // __kmp_launch_worker. So when thread is created (goes into
783   // __kmp_launch_worker) it will set its __thread local pointer to
784   // th->th.th_stats
785   if (!KMP_UBER_GTID(gtid)) {
786     th->th.th_stats = __kmp_stats_list->push_back(gtid);
787   } else {
788     // For root threads, __kmp_stats_thread_ptr is set in __kmp_register_root(),
789     // so set the th->th.th_stats field to it.
790     th->th.th_stats = __kmp_stats_thread_ptr;
791   }
792   __kmp_release_tas_lock(&__kmp_stats_lock, gtid);
793 
794 #endif // KMP_STATS_ENABLED
795 
796   if (KMP_UBER_GTID(gtid)) {
797     KA_TRACE(10, ("__kmp_create_worker: uber thread (%d)\n", gtid));
798     th->th.th_info.ds.ds_thread = pthread_self();
799     __kmp_set_stack_info(gtid, th);
800     __kmp_check_stack_overlap(th);
801     return;
802   }; // if
803 
804   KA_TRACE(10, ("__kmp_create_worker: try to create thread (%d)\n", gtid));
805 
806   KMP_MB(); /* Flush all pending memory write invalidates.  */
807 
808 #ifdef KMP_THREAD_ATTR
809   status = pthread_attr_init(&thread_attr);
810   if (status != 0) {
811     __kmp_msg(kmp_ms_fatal, KMP_MSG(CantInitThreadAttrs), KMP_ERR(status),
812               __kmp_msg_null);
813   }; // if
814   status = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_JOINABLE);
815   if (status != 0) {
816     __kmp_msg(kmp_ms_fatal, KMP_MSG(CantSetWorkerState), KMP_ERR(status),
817               __kmp_msg_null);
818   }; // if
819 
820   /* Set stack size for this thread now.
821      The multiple of 2 is there because on some machines, requesting an unusual
822      stacksize causes the thread to have an offset before the dummy alloca()
823      takes place to create the offset.  Since we want the user to have a
824      sufficient stacksize AND support a stack offset, we alloca() twice the
825      offset so that the upcoming alloca() does not eliminate any premade offset,
826      and also gives the user the stack space they requested for all threads */
827   stack_size += gtid * __kmp_stkoffset * 2;
828 
829   KA_TRACE(10, ("__kmp_create_worker: T#%d, default stacksize = %lu bytes, "
830                 "__kmp_stksize = %lu bytes, final stacksize = %lu bytes\n",
831                 gtid, KMP_DEFAULT_STKSIZE, __kmp_stksize, stack_size));
832 
833 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
834   status = pthread_attr_setstacksize(&thread_attr, stack_size);
835 #ifdef KMP_BACKUP_STKSIZE
836   if (status != 0) {
837     if (!__kmp_env_stksize) {
838       stack_size = KMP_BACKUP_STKSIZE + gtid * __kmp_stkoffset;
839       __kmp_stksize = KMP_BACKUP_STKSIZE;
840       KA_TRACE(10, ("__kmp_create_worker: T#%d, default stacksize = %lu bytes, "
841                     "__kmp_stksize = %lu bytes, (backup) final stacksize = %lu "
842                     "bytes\n",
843                     gtid, KMP_DEFAULT_STKSIZE, __kmp_stksize, stack_size));
844       status = pthread_attr_setstacksize(&thread_attr, stack_size);
845     }; // if
846   }; // if
847 #endif /* KMP_BACKUP_STKSIZE */
848   if (status != 0) {
849     __kmp_msg(kmp_ms_fatal, KMP_MSG(CantSetWorkerStackSize, stack_size),
850               KMP_ERR(status), KMP_HNT(ChangeWorkerStackSize), __kmp_msg_null);
851   }; // if
852 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
853 
854 #endif /* KMP_THREAD_ATTR */
855 
856   status =
857       pthread_create(&handle, &thread_attr, __kmp_launch_worker, (void *)th);
858   if (status != 0 || !handle) { // ??? Why do we check handle??
859 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
860     if (status == EINVAL) {
861       __kmp_msg(kmp_ms_fatal, KMP_MSG(CantSetWorkerStackSize, stack_size),
862                 KMP_ERR(status), KMP_HNT(IncreaseWorkerStackSize),
863                 __kmp_msg_null);
864     };
865     if (status == ENOMEM) {
866       __kmp_msg(kmp_ms_fatal, KMP_MSG(CantSetWorkerStackSize, stack_size),
867                 KMP_ERR(status), KMP_HNT(DecreaseWorkerStackSize),
868                 __kmp_msg_null);
869     };
870 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
871     if (status == EAGAIN) {
872       __kmp_msg(kmp_ms_fatal, KMP_MSG(NoResourcesForWorkerThread),
873                 KMP_ERR(status), KMP_HNT(Decrease_NUM_THREADS), __kmp_msg_null);
874     }; // if
875     KMP_SYSFAIL("pthread_create", status);
876   }; // if
877 
878   th->th.th_info.ds.ds_thread = handle;
879 
880 #ifdef KMP_THREAD_ATTR
881   status = pthread_attr_destroy(&thread_attr);
882   if (status) {
883     kmp_msg_t err_code = KMP_ERR(status);
884     __kmp_msg(kmp_ms_warning, KMP_MSG(CantDestroyThreadAttrs), err_code,
885               __kmp_msg_null);
886     if (__kmp_generate_warnings == kmp_warnings_off) {
887       __kmp_str_free(&err_code.str);
888     }
889   }; // if
890 #endif /* KMP_THREAD_ATTR */
891 
892   KMP_MB(); /* Flush all pending memory write invalidates.  */
893 
894   KA_TRACE(10, ("__kmp_create_worker: done creating thread (%d)\n", gtid));
895 
896 } // __kmp_create_worker
897 
898 #if KMP_USE_MONITOR
899 void __kmp_create_monitor(kmp_info_t *th) {
900   pthread_t handle;
901   pthread_attr_t thread_attr;
902   size_t size;
903   int status;
904   int auto_adj_size = FALSE;
905 
906   if (__kmp_dflt_blocktime == KMP_MAX_BLOCKTIME) {
907     // We don't need monitor thread in case of MAX_BLOCKTIME
908     KA_TRACE(10, ("__kmp_create_monitor: skipping monitor thread because of "
909                   "MAX blocktime\n"));
910     th->th.th_info.ds.ds_tid = 0; // this makes reap_monitor no-op
911     th->th.th_info.ds.ds_gtid = 0;
912     return;
913   }
914   KA_TRACE(10, ("__kmp_create_monitor: try to create monitor\n"));
915 
916   KMP_MB(); /* Flush all pending memory write invalidates.  */
917 
918   th->th.th_info.ds.ds_tid = KMP_GTID_MONITOR;
919   th->th.th_info.ds.ds_gtid = KMP_GTID_MONITOR;
920 #if KMP_REAL_TIME_FIX
921   TCW_4(__kmp_global.g.g_time.dt.t_value,
922         -1); // Will use it for synchronization a bit later.
923 #else
924   TCW_4(__kmp_global.g.g_time.dt.t_value, 0);
925 #endif // KMP_REAL_TIME_FIX
926 
927 #ifdef KMP_THREAD_ATTR
928   if (__kmp_monitor_stksize == 0) {
929     __kmp_monitor_stksize = KMP_DEFAULT_MONITOR_STKSIZE;
930     auto_adj_size = TRUE;
931   }
932   status = pthread_attr_init(&thread_attr);
933   if (status != 0) {
934     __kmp_msg(kmp_ms_fatal, KMP_MSG(CantInitThreadAttrs), KMP_ERR(status),
935               __kmp_msg_null);
936   }; // if
937   status = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_JOINABLE);
938   if (status != 0) {
939     __kmp_msg(kmp_ms_fatal, KMP_MSG(CantSetMonitorState), KMP_ERR(status),
940               __kmp_msg_null);
941   }; // if
942 
943 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
944   status = pthread_attr_getstacksize(&thread_attr, &size);
945   KMP_CHECK_SYSFAIL("pthread_attr_getstacksize", status);
946 #else
947   size = __kmp_sys_min_stksize;
948 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
949 #endif /* KMP_THREAD_ATTR */
950 
951   if (__kmp_monitor_stksize == 0) {
952     __kmp_monitor_stksize = KMP_DEFAULT_MONITOR_STKSIZE;
953   }
954   if (__kmp_monitor_stksize < __kmp_sys_min_stksize) {
955     __kmp_monitor_stksize = __kmp_sys_min_stksize;
956   }
957 
958   KA_TRACE(10, ("__kmp_create_monitor: default stacksize = %lu bytes,"
959                 "requested stacksize = %lu bytes\n",
960                 size, __kmp_monitor_stksize));
961 
962 retry:
963 
964 /* Set stack size for this thread now. */
965 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
966   KA_TRACE(10, ("__kmp_create_monitor: setting stacksize = %lu bytes,",
967                 __kmp_monitor_stksize));
968   status = pthread_attr_setstacksize(&thread_attr, __kmp_monitor_stksize);
969   if (status != 0) {
970     if (auto_adj_size) {
971       __kmp_monitor_stksize *= 2;
972       goto retry;
973     }
974     kmp_msg_t err_code = KMP_ERR(status);
975     __kmp_msg(kmp_ms_warning, // should this be fatal?  BB
976               KMP_MSG(CantSetMonitorStackSize, (long int)__kmp_monitor_stksize),
977               err_code, KMP_HNT(ChangeMonitorStackSize), __kmp_msg_null);
978     if (__kmp_generate_warnings == kmp_warnings_off) {
979       __kmp_str_free(&err_code.str);
980     }
981   }; // if
982 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
983 
984   status =
985       pthread_create(&handle, &thread_attr, __kmp_launch_monitor, (void *)th);
986 
987   if (status != 0) {
988 #ifdef _POSIX_THREAD_ATTR_STACKSIZE
989     if (status == EINVAL) {
990       if (auto_adj_size && (__kmp_monitor_stksize < (size_t)0x40000000)) {
991         __kmp_monitor_stksize *= 2;
992         goto retry;
993       }
994       __kmp_msg(
995           kmp_ms_fatal, KMP_MSG(CantSetMonitorStackSize, __kmp_monitor_stksize),
996           KMP_ERR(status), KMP_HNT(IncreaseMonitorStackSize), __kmp_msg_null);
997     }; // if
998     if (status == ENOMEM) {
999       __kmp_msg(
1000           kmp_ms_fatal, KMP_MSG(CantSetMonitorStackSize, __kmp_monitor_stksize),
1001           KMP_ERR(status), KMP_HNT(DecreaseMonitorStackSize), __kmp_msg_null);
1002     }; // if
1003 #endif /* _POSIX_THREAD_ATTR_STACKSIZE */
1004     if (status == EAGAIN) {
1005       __kmp_msg(kmp_ms_fatal, KMP_MSG(NoResourcesForMonitorThread),
1006                 KMP_ERR(status), KMP_HNT(DecreaseNumberOfThreadsInUse),
1007                 __kmp_msg_null);
1008     }; // if
1009     KMP_SYSFAIL("pthread_create", status);
1010   }; // if
1011 
1012   th->th.th_info.ds.ds_thread = handle;
1013 
1014 #if KMP_REAL_TIME_FIX
1015   // Wait for the monitor thread is really started and set its *priority*.
1016   KMP_DEBUG_ASSERT(sizeof(kmp_uint32) ==
1017                    sizeof(__kmp_global.g.g_time.dt.t_value));
1018   __kmp_wait_yield_4((kmp_uint32 volatile *)&__kmp_global.g.g_time.dt.t_value,
1019                      -1, &__kmp_neq_4, NULL);
1020 #endif // KMP_REAL_TIME_FIX
1021 
1022 #ifdef KMP_THREAD_ATTR
1023   status = pthread_attr_destroy(&thread_attr);
1024   if (status != 0) {
1025     kmp_msg_t err_code = KMP_ERR(status);
1026     __kmp_msg(kmp_ms_warning, KMP_MSG(CantDestroyThreadAttrs), err_code,
1027               __kmp_msg_null);
1028     if (__kmp_generate_warnings == kmp_warnings_off) {
1029       __kmp_str_free(&err_code.str);
1030     }
1031   }; // if
1032 #endif
1033 
1034   KMP_MB(); /* Flush all pending memory write invalidates.  */
1035 
1036   KA_TRACE(10, ("__kmp_create_monitor: monitor created %#.8lx\n",
1037                 th->th.th_info.ds.ds_thread));
1038 
1039 } // __kmp_create_monitor
1040 #endif // KMP_USE_MONITOR
1041 
1042 void __kmp_exit_thread(int exit_status) {
1043   pthread_exit((void *)(intptr_t)exit_status);
1044 } // __kmp_exit_thread
1045 
1046 #if KMP_USE_MONITOR
1047 void __kmp_resume_monitor();
1048 
1049 void __kmp_reap_monitor(kmp_info_t *th) {
1050   int status;
1051   void *exit_val;
1052 
1053   KA_TRACE(10, ("__kmp_reap_monitor: try to reap monitor thread with handle"
1054                 " %#.8lx\n",
1055                 th->th.th_info.ds.ds_thread));
1056 
1057   // If monitor has been created, its tid and gtid should be KMP_GTID_MONITOR.
1058   // If both tid and gtid are 0, it means the monitor did not ever start.
1059   // If both tid and gtid are KMP_GTID_DNE, the monitor has been shut down.
1060   KMP_DEBUG_ASSERT(th->th.th_info.ds.ds_tid == th->th.th_info.ds.ds_gtid);
1061   if (th->th.th_info.ds.ds_gtid != KMP_GTID_MONITOR) {
1062     KA_TRACE(10, ("__kmp_reap_monitor: monitor did not start, returning\n"));
1063     return;
1064   }; // if
1065 
1066   KMP_MB(); /* Flush all pending memory write invalidates.  */
1067 
1068   /* First, check to see whether the monitor thread exists to wake it up. This
1069      is to avoid performance problem when the monitor sleeps during
1070      blocktime-size interval */
1071 
1072   status = pthread_kill(th->th.th_info.ds.ds_thread, 0);
1073   if (status != ESRCH) {
1074     __kmp_resume_monitor(); // Wake up the monitor thread
1075   }
1076   KA_TRACE(10, ("__kmp_reap_monitor: try to join with monitor\n"));
1077   status = pthread_join(th->th.th_info.ds.ds_thread, &exit_val);
1078   if (exit_val != th) {
1079     __kmp_msg(kmp_ms_fatal, KMP_MSG(ReapMonitorError), KMP_ERR(status),
1080               __kmp_msg_null);
1081   }
1082 
1083   th->th.th_info.ds.ds_tid = KMP_GTID_DNE;
1084   th->th.th_info.ds.ds_gtid = KMP_GTID_DNE;
1085 
1086   KA_TRACE(10, ("__kmp_reap_monitor: done reaping monitor thread with handle"
1087                 " %#.8lx\n",
1088                 th->th.th_info.ds.ds_thread));
1089 
1090   KMP_MB(); /* Flush all pending memory write invalidates.  */
1091 }
1092 #endif // KMP_USE_MONITOR
1093 
1094 void __kmp_reap_worker(kmp_info_t *th) {
1095   int status;
1096   void *exit_val;
1097 
1098   KMP_MB(); /* Flush all pending memory write invalidates.  */
1099 
1100   KA_TRACE(
1101       10, ("__kmp_reap_worker: try to reap T#%d\n", th->th.th_info.ds.ds_gtid));
1102 
1103   status = pthread_join(th->th.th_info.ds.ds_thread, &exit_val);
1104 #ifdef KMP_DEBUG
1105   /* Don't expose these to the user until we understand when they trigger */
1106   if (status != 0) {
1107     __kmp_msg(kmp_ms_fatal, KMP_MSG(ReapWorkerError), KMP_ERR(status),
1108               __kmp_msg_null);
1109   }
1110   if (exit_val != th) {
1111     KA_TRACE(10, ("__kmp_reap_worker: worker T#%d did not reap properly, "
1112                   "exit_val = %p\n",
1113                   th->th.th_info.ds.ds_gtid, exit_val));
1114   }
1115 #endif /* KMP_DEBUG */
1116 
1117   KA_TRACE(10, ("__kmp_reap_worker: done reaping T#%d\n",
1118                 th->th.th_info.ds.ds_gtid));
1119 
1120   KMP_MB(); /* Flush all pending memory write invalidates.  */
1121 }
1122 
1123 #if KMP_HANDLE_SIGNALS
1124 
1125 static void __kmp_null_handler(int signo) {
1126   //  Do nothing, for doing SIG_IGN-type actions.
1127 } // __kmp_null_handler
1128 
1129 static void __kmp_team_handler(int signo) {
1130   if (__kmp_global.g.g_abort == 0) {
1131 /* Stage 1 signal handler, let's shut down all of the threads */
1132 #ifdef KMP_DEBUG
1133     __kmp_debug_printf("__kmp_team_handler: caught signal = %d\n", signo);
1134 #endif
1135     switch (signo) {
1136     case SIGHUP:
1137     case SIGINT:
1138     case SIGQUIT:
1139     case SIGILL:
1140     case SIGABRT:
1141     case SIGFPE:
1142     case SIGBUS:
1143     case SIGSEGV:
1144 #ifdef SIGSYS
1145     case SIGSYS:
1146 #endif
1147     case SIGTERM:
1148       if (__kmp_debug_buf) {
1149         __kmp_dump_debug_buffer();
1150       }; // if
1151       KMP_MB(); // Flush all pending memory write invalidates.
1152       TCW_4(__kmp_global.g.g_abort, signo);
1153       KMP_MB(); // Flush all pending memory write invalidates.
1154       TCW_4(__kmp_global.g.g_done, TRUE);
1155       KMP_MB(); // Flush all pending memory write invalidates.
1156       break;
1157     default:
1158 #ifdef KMP_DEBUG
1159       __kmp_debug_printf("__kmp_team_handler: unknown signal type");
1160 #endif
1161       break;
1162     }; // switch
1163   }; // if
1164 } // __kmp_team_handler
1165 
1166 static void __kmp_sigaction(int signum, const struct sigaction *act,
1167                             struct sigaction *oldact) {
1168   int rc = sigaction(signum, act, oldact);
1169   KMP_CHECK_SYSFAIL_ERRNO("sigaction", rc);
1170 }
1171 
1172 static void __kmp_install_one_handler(int sig, sig_func_t handler_func,
1173                                       int parallel_init) {
1174   KMP_MB(); // Flush all pending memory write invalidates.
1175   KB_TRACE(60,
1176            ("__kmp_install_one_handler( %d, ..., %d )\n", sig, parallel_init));
1177   if (parallel_init) {
1178     struct sigaction new_action;
1179     struct sigaction old_action;
1180     new_action.sa_handler = handler_func;
1181     new_action.sa_flags = 0;
1182     sigfillset(&new_action.sa_mask);
1183     __kmp_sigaction(sig, &new_action, &old_action);
1184     if (old_action.sa_handler == __kmp_sighldrs[sig].sa_handler) {
1185       sigaddset(&__kmp_sigset, sig);
1186     } else {
1187       // Restore/keep user's handler if one previously installed.
1188       __kmp_sigaction(sig, &old_action, NULL);
1189     }; // if
1190   } else {
1191     // Save initial/system signal handlers to see if user handlers installed.
1192     __kmp_sigaction(sig, NULL, &__kmp_sighldrs[sig]);
1193   }; // if
1194   KMP_MB(); // Flush all pending memory write invalidates.
1195 } // __kmp_install_one_handler
1196 
1197 static void __kmp_remove_one_handler(int sig) {
1198   KB_TRACE(60, ("__kmp_remove_one_handler( %d )\n", sig));
1199   if (sigismember(&__kmp_sigset, sig)) {
1200     struct sigaction old;
1201     KMP_MB(); // Flush all pending memory write invalidates.
1202     __kmp_sigaction(sig, &__kmp_sighldrs[sig], &old);
1203     if ((old.sa_handler != __kmp_team_handler) &&
1204         (old.sa_handler != __kmp_null_handler)) {
1205       // Restore the users signal handler.
1206       KB_TRACE(10, ("__kmp_remove_one_handler: oops, not our handler, "
1207                     "restoring: sig=%d\n",
1208                     sig));
1209       __kmp_sigaction(sig, &old, NULL);
1210     }; // if
1211     sigdelset(&__kmp_sigset, sig);
1212     KMP_MB(); // Flush all pending memory write invalidates.
1213   }; // if
1214 } // __kmp_remove_one_handler
1215 
1216 void __kmp_install_signals(int parallel_init) {
1217   KB_TRACE(10, ("__kmp_install_signals( %d )\n", parallel_init));
1218   if (__kmp_handle_signals || !parallel_init) {
1219     // If ! parallel_init, we do not install handlers, just save original
1220     // handlers. Let us do it even __handle_signals is 0.
1221     sigemptyset(&__kmp_sigset);
1222     __kmp_install_one_handler(SIGHUP, __kmp_team_handler, parallel_init);
1223     __kmp_install_one_handler(SIGINT, __kmp_team_handler, parallel_init);
1224     __kmp_install_one_handler(SIGQUIT, __kmp_team_handler, parallel_init);
1225     __kmp_install_one_handler(SIGILL, __kmp_team_handler, parallel_init);
1226     __kmp_install_one_handler(SIGABRT, __kmp_team_handler, parallel_init);
1227     __kmp_install_one_handler(SIGFPE, __kmp_team_handler, parallel_init);
1228     __kmp_install_one_handler(SIGBUS, __kmp_team_handler, parallel_init);
1229     __kmp_install_one_handler(SIGSEGV, __kmp_team_handler, parallel_init);
1230 #ifdef SIGSYS
1231     __kmp_install_one_handler(SIGSYS, __kmp_team_handler, parallel_init);
1232 #endif // SIGSYS
1233     __kmp_install_one_handler(SIGTERM, __kmp_team_handler, parallel_init);
1234 #ifdef SIGPIPE
1235     __kmp_install_one_handler(SIGPIPE, __kmp_team_handler, parallel_init);
1236 #endif // SIGPIPE
1237   }; // if
1238 } // __kmp_install_signals
1239 
1240 void __kmp_remove_signals(void) {
1241   int sig;
1242   KB_TRACE(10, ("__kmp_remove_signals()\n"));
1243   for (sig = 1; sig < NSIG; ++sig) {
1244     __kmp_remove_one_handler(sig);
1245   }; // for sig
1246 } // __kmp_remove_signals
1247 
1248 #endif // KMP_HANDLE_SIGNALS
1249 
1250 void __kmp_enable(int new_state) {
1251 #ifdef KMP_CANCEL_THREADS
1252   int status, old_state;
1253   status = pthread_setcancelstate(new_state, &old_state);
1254   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
1255   KMP_DEBUG_ASSERT(old_state == PTHREAD_CANCEL_DISABLE);
1256 #endif
1257 }
1258 
1259 void __kmp_disable(int *old_state) {
1260 #ifdef KMP_CANCEL_THREADS
1261   int status;
1262   status = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, old_state);
1263   KMP_CHECK_SYSFAIL("pthread_setcancelstate", status);
1264 #endif
1265 }
1266 
1267 static void __kmp_atfork_prepare(void) { /*  nothing to do  */
1268 }
1269 
1270 static void __kmp_atfork_parent(void) { /*  nothing to do  */
1271 }
1272 
1273 /* Reset the library so execution in the child starts "all over again" with
1274    clean data structures in initial states.  Don't worry about freeing memory
1275    allocated by parent, just abandon it to be safe. */
1276 static void __kmp_atfork_child(void) {
1277   /* TODO make sure this is done right for nested/sibling */
1278   // ATT:  Memory leaks are here? TODO: Check it and fix.
1279   /* KMP_ASSERT( 0 ); */
1280 
1281   ++__kmp_fork_count;
1282 
1283 #if KMP_AFFINITY_SUPPORTED
1284 #if KMP_OS_LINUX
1285   // reset the affinity in the child to the initial thread
1286   // affinity in the parent
1287   kmp_set_thread_affinity_mask_initial();
1288 #endif
1289   // Set default not to bind threads tightly in the child (we’re expecting
1290   // over-subscription after the fork and this can improve things for
1291   // scripting languages that use OpenMP inside process-parallel code).
1292   __kmp_affinity_type = affinity_none;
1293 #if OMP_40_ENABLED
1294   if (__kmp_nested_proc_bind.bind_types != NULL) {
1295     __kmp_nested_proc_bind.bind_types[0] = proc_bind_false;
1296   }
1297 #endif // OMP_40_ENABLED
1298 #endif // KMP_AFFINITY_SUPPORTED
1299 
1300   __kmp_init_runtime = FALSE;
1301 #if KMP_USE_MONITOR
1302   __kmp_init_monitor = 0;
1303 #endif
1304   __kmp_init_parallel = FALSE;
1305   __kmp_init_middle = FALSE;
1306   __kmp_init_serial = FALSE;
1307   TCW_4(__kmp_init_gtid, FALSE);
1308   __kmp_init_common = FALSE;
1309 
1310   TCW_4(__kmp_init_user_locks, FALSE);
1311 #if !KMP_USE_DYNAMIC_LOCK
1312   __kmp_user_lock_table.used = 1;
1313   __kmp_user_lock_table.allocated = 0;
1314   __kmp_user_lock_table.table = NULL;
1315   __kmp_lock_blocks = NULL;
1316 #endif
1317 
1318   __kmp_all_nth = 0;
1319   TCW_4(__kmp_nth, 0);
1320 
1321   /* Must actually zero all the *cache arguments passed to __kmpc_threadprivate
1322      here so threadprivate doesn't use stale data */
1323   KA_TRACE(10, ("__kmp_atfork_child: checking cache address list %p\n",
1324                 __kmp_threadpriv_cache_list));
1325 
1326   while (__kmp_threadpriv_cache_list != NULL) {
1327 
1328     if (*__kmp_threadpriv_cache_list->addr != NULL) {
1329       KC_TRACE(50, ("__kmp_atfork_child: zeroing cache at address %p\n",
1330                     &(*__kmp_threadpriv_cache_list->addr)));
1331 
1332       *__kmp_threadpriv_cache_list->addr = NULL;
1333     }
1334     __kmp_threadpriv_cache_list = __kmp_threadpriv_cache_list->next;
1335   }
1336 
1337   __kmp_init_runtime = FALSE;
1338 
1339   /* reset statically initialized locks */
1340   __kmp_init_bootstrap_lock(&__kmp_initz_lock);
1341   __kmp_init_bootstrap_lock(&__kmp_stdio_lock);
1342   __kmp_init_bootstrap_lock(&__kmp_console_lock);
1343 
1344   /* This is necessary to make sure no stale data is left around */
1345   /* AC: customers complain that we use unsafe routines in the atfork
1346      handler. Mathworks: dlsym() is unsafe. We call dlsym and dlopen
1347      in dynamic_link when check the presence of shared tbbmalloc library.
1348      Suggestion is to make the library initialization lazier, similar
1349      to what done for __kmpc_begin(). */
1350   // TODO: synchronize all static initializations with regular library
1351   //       startup; look at kmp_global.cpp and etc.
1352   //__kmp_internal_begin ();
1353 }
1354 
1355 void __kmp_register_atfork(void) {
1356   if (__kmp_need_register_atfork) {
1357     int status = pthread_atfork(__kmp_atfork_prepare, __kmp_atfork_parent,
1358                                 __kmp_atfork_child);
1359     KMP_CHECK_SYSFAIL("pthread_atfork", status);
1360     __kmp_need_register_atfork = FALSE;
1361   }
1362 }
1363 
1364 void __kmp_suspend_initialize(void) {
1365   int status;
1366   status = pthread_mutexattr_init(&__kmp_suspend_mutex_attr);
1367   KMP_CHECK_SYSFAIL("pthread_mutexattr_init", status);
1368   status = pthread_condattr_init(&__kmp_suspend_cond_attr);
1369   KMP_CHECK_SYSFAIL("pthread_condattr_init", status);
1370 }
1371 
1372 static void __kmp_suspend_initialize_thread(kmp_info_t *th) {
1373   ANNOTATE_HAPPENS_AFTER(&th->th.th_suspend_init_count);
1374   if (th->th.th_suspend_init_count <= __kmp_fork_count) {
1375     /* this means we haven't initialized the suspension pthread objects for this
1376        thread in this instance of the process */
1377     int status;
1378     status = pthread_cond_init(&th->th.th_suspend_cv.c_cond,
1379                                &__kmp_suspend_cond_attr);
1380     KMP_CHECK_SYSFAIL("pthread_cond_init", status);
1381     status = pthread_mutex_init(&th->th.th_suspend_mx.m_mutex,
1382                                 &__kmp_suspend_mutex_attr);
1383     KMP_CHECK_SYSFAIL("pthread_mutex_init", status);
1384     *(volatile int *)&th->th.th_suspend_init_count = __kmp_fork_count + 1;
1385     ANNOTATE_HAPPENS_BEFORE(&th->th.th_suspend_init_count);
1386   };
1387 }
1388 
1389 void __kmp_suspend_uninitialize_thread(kmp_info_t *th) {
1390   if (th->th.th_suspend_init_count > __kmp_fork_count) {
1391     /* this means we have initialize the suspension pthread objects for this
1392        thread in this instance of the process */
1393     int status;
1394 
1395     status = pthread_cond_destroy(&th->th.th_suspend_cv.c_cond);
1396     if (status != 0 && status != EBUSY) {
1397       KMP_SYSFAIL("pthread_cond_destroy", status);
1398     };
1399     status = pthread_mutex_destroy(&th->th.th_suspend_mx.m_mutex);
1400     if (status != 0 && status != EBUSY) {
1401       KMP_SYSFAIL("pthread_mutex_destroy", status);
1402     };
1403     --th->th.th_suspend_init_count;
1404     KMP_DEBUG_ASSERT(th->th.th_suspend_init_count == __kmp_fork_count);
1405   }
1406 }
1407 
1408 
1409 /* This routine puts the calling thread to sleep after setting the
1410    sleep bit for the indicated flag variable to true. */
1411 template <class C>
1412 static inline void __kmp_suspend_template(int th_gtid, C *flag) {
1413   KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_suspend);
1414   kmp_info_t *th = __kmp_threads[th_gtid];
1415   int status;
1416   typename C::flag_t old_spin;
1417 
1418   KF_TRACE(30, ("__kmp_suspend_template: T#%d enter for flag = %p\n", th_gtid,
1419                 flag->get()));
1420 
1421   __kmp_suspend_initialize_thread(th);
1422 
1423   status = pthread_mutex_lock(&th->th.th_suspend_mx.m_mutex);
1424   KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
1425 
1426   KF_TRACE(10, ("__kmp_suspend_template: T#%d setting sleep bit for spin(%p)\n",
1427                 th_gtid, flag->get()));
1428 
1429   /* TODO: shouldn't this use release semantics to ensure that
1430      __kmp_suspend_initialize_thread gets called first? */
1431   old_spin = flag->set_sleeping();
1432 
1433   KF_TRACE(5, ("__kmp_suspend_template: T#%d set sleep bit for spin(%p)==%x,"
1434                " was %x\n",
1435                th_gtid, flag->get(), *(flag->get()), old_spin));
1436 
1437   if (flag->done_check_val(old_spin)) {
1438     old_spin = flag->unset_sleeping();
1439     KF_TRACE(5, ("__kmp_suspend_template: T#%d false alarm, reset sleep bit "
1440                  "for spin(%p)\n",
1441                  th_gtid, flag->get()));
1442   } else {
1443     /* Encapsulate in a loop as the documentation states that this may
1444        "with low probability" return when the condition variable has
1445        not been signaled or broadcast */
1446     int deactivated = FALSE;
1447     TCW_PTR(th->th.th_sleep_loc, (void *)flag);
1448 
1449     while (flag->is_sleeping()) {
1450 #ifdef DEBUG_SUSPEND
1451       char buffer[128];
1452       __kmp_suspend_count++;
1453       __kmp_print_cond(buffer, &th->th.th_suspend_cv);
1454       __kmp_printf("__kmp_suspend_template: suspending T#%d: %s\n", th_gtid,
1455                    buffer);
1456 #endif
1457       // Mark the thread as no longer active (only in the first iteration of the
1458       // loop).
1459       if (!deactivated) {
1460         th->th.th_active = FALSE;
1461         if (th->th.th_active_in_pool) {
1462           th->th.th_active_in_pool = FALSE;
1463           KMP_TEST_THEN_DEC32(&__kmp_thread_pool_active_nth);
1464           KMP_DEBUG_ASSERT(TCR_4(__kmp_thread_pool_active_nth) >= 0);
1465         }
1466         deactivated = TRUE;
1467       }
1468 
1469 #if USE_SUSPEND_TIMEOUT
1470       struct timespec now;
1471       struct timeval tval;
1472       int msecs;
1473 
1474       status = gettimeofday(&tval, NULL);
1475       KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1476       TIMEVAL_TO_TIMESPEC(&tval, &now);
1477 
1478       msecs = (4 * __kmp_dflt_blocktime) + 200;
1479       now.tv_sec += msecs / 1000;
1480       now.tv_nsec += (msecs % 1000) * 1000;
1481 
1482       KF_TRACE(15, ("__kmp_suspend_template: T#%d about to perform "
1483                     "pthread_cond_timedwait\n",
1484                     th_gtid));
1485       status = pthread_cond_timedwait(&th->th.th_suspend_cv.c_cond,
1486                                       &th->th.th_suspend_mx.m_mutex, &now);
1487 #else
1488       KF_TRACE(15, ("__kmp_suspend_template: T#%d about to perform"
1489                     " pthread_cond_wait\n",
1490                     th_gtid));
1491       status = pthread_cond_wait(&th->th.th_suspend_cv.c_cond,
1492                                  &th->th.th_suspend_mx.m_mutex);
1493 #endif
1494 
1495       if ((status != 0) && (status != EINTR) && (status != ETIMEDOUT)) {
1496         KMP_SYSFAIL("pthread_cond_wait", status);
1497       }
1498 #ifdef KMP_DEBUG
1499       if (status == ETIMEDOUT) {
1500         if (flag->is_sleeping()) {
1501           KF_TRACE(100,
1502                    ("__kmp_suspend_template: T#%d timeout wakeup\n", th_gtid));
1503         } else {
1504           KF_TRACE(2, ("__kmp_suspend_template: T#%d timeout wakeup, sleep bit "
1505                        "not set!\n",
1506                        th_gtid));
1507         }
1508       } else if (flag->is_sleeping()) {
1509         KF_TRACE(100,
1510                  ("__kmp_suspend_template: T#%d spurious wakeup\n", th_gtid));
1511       }
1512 #endif
1513     } // while
1514 
1515     // Mark the thread as active again (if it was previous marked as inactive)
1516     if (deactivated) {
1517       th->th.th_active = TRUE;
1518       if (TCR_4(th->th.th_in_pool)) {
1519         KMP_TEST_THEN_INC32(&__kmp_thread_pool_active_nth);
1520         th->th.th_active_in_pool = TRUE;
1521       }
1522     }
1523   }
1524 #ifdef DEBUG_SUSPEND
1525   {
1526     char buffer[128];
1527     __kmp_print_cond(buffer, &th->th.th_suspend_cv);
1528     __kmp_printf("__kmp_suspend_template: T#%d has awakened: %s\n", th_gtid,
1529                  buffer);
1530   }
1531 #endif
1532 
1533   status = pthread_mutex_unlock(&th->th.th_suspend_mx.m_mutex);
1534   KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1535   KF_TRACE(30, ("__kmp_suspend_template: T#%d exit\n", th_gtid));
1536 }
1537 
1538 void __kmp_suspend_32(int th_gtid, kmp_flag_32 *flag) {
1539   __kmp_suspend_template(th_gtid, flag);
1540 }
1541 void __kmp_suspend_64(int th_gtid, kmp_flag_64 *flag) {
1542   __kmp_suspend_template(th_gtid, flag);
1543 }
1544 void __kmp_suspend_oncore(int th_gtid, kmp_flag_oncore *flag) {
1545   __kmp_suspend_template(th_gtid, flag);
1546 }
1547 
1548 /* This routine signals the thread specified by target_gtid to wake up
1549    after setting the sleep bit indicated by the flag argument to FALSE.
1550    The target thread must already have called __kmp_suspend_template() */
1551 template <class C>
1552 static inline void __kmp_resume_template(int target_gtid, C *flag) {
1553   KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_resume);
1554   kmp_info_t *th = __kmp_threads[target_gtid];
1555   int status;
1556 
1557 #ifdef KMP_DEBUG
1558   int gtid = TCR_4(__kmp_init_gtid) ? __kmp_get_gtid() : -1;
1559 #endif
1560 
1561   KF_TRACE(30, ("__kmp_resume_template: T#%d wants to wakeup T#%d enter\n",
1562                 gtid, target_gtid));
1563   KMP_DEBUG_ASSERT(gtid != target_gtid);
1564 
1565   __kmp_suspend_initialize_thread(th);
1566 
1567   status = pthread_mutex_lock(&th->th.th_suspend_mx.m_mutex);
1568   KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
1569 
1570   if (!flag) { // coming from __kmp_null_resume_wrapper
1571     flag = (C *)CCAST(void *, th->th.th_sleep_loc);
1572   }
1573 
1574   // First, check if the flag is null or its type has changed. If so, someone
1575   // else woke it up.
1576   if (!flag || flag->get_type() != flag->get_ptr_type()) { // get_ptr_type
1577     // simply shows what
1578     // flag was cast to
1579     KF_TRACE(5, ("__kmp_resume_template: T#%d exiting, thread T#%d already "
1580                  "awake: flag(%p)\n",
1581                  gtid, target_gtid, NULL));
1582     status = pthread_mutex_unlock(&th->th.th_suspend_mx.m_mutex);
1583     KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1584     return;
1585   } else { // if multiple threads are sleeping, flag should be internally
1586     // referring to a specific thread here
1587     typename C::flag_t old_spin = flag->unset_sleeping();
1588     if (!flag->is_sleeping_val(old_spin)) {
1589       KF_TRACE(5, ("__kmp_resume_template: T#%d exiting, thread T#%d already "
1590                    "awake: flag(%p): "
1591                    "%u => %u\n",
1592                    gtid, target_gtid, flag->get(), old_spin, *flag->get()));
1593       status = pthread_mutex_unlock(&th->th.th_suspend_mx.m_mutex);
1594       KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1595       return;
1596     }
1597     KF_TRACE(5, ("__kmp_resume_template: T#%d about to wakeup T#%d, reset "
1598                  "sleep bit for flag's loc(%p): "
1599                  "%u => %u\n",
1600                  gtid, target_gtid, flag->get(), old_spin, *flag->get()));
1601   }
1602   TCW_PTR(th->th.th_sleep_loc, NULL);
1603 
1604 #ifdef DEBUG_SUSPEND
1605   {
1606     char buffer[128];
1607     __kmp_print_cond(buffer, &th->th.th_suspend_cv);
1608     __kmp_printf("__kmp_resume_template: T#%d resuming T#%d: %s\n", gtid,
1609                  target_gtid, buffer);
1610   }
1611 #endif
1612   status = pthread_cond_signal(&th->th.th_suspend_cv.c_cond);
1613   KMP_CHECK_SYSFAIL("pthread_cond_signal", status);
1614   status = pthread_mutex_unlock(&th->th.th_suspend_mx.m_mutex);
1615   KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1616   KF_TRACE(30, ("__kmp_resume_template: T#%d exiting after signaling wake up"
1617                 " for T#%d\n",
1618                 gtid, target_gtid));
1619 }
1620 
1621 void __kmp_resume_32(int target_gtid, kmp_flag_32 *flag) {
1622   __kmp_resume_template(target_gtid, flag);
1623 }
1624 void __kmp_resume_64(int target_gtid, kmp_flag_64 *flag) {
1625   __kmp_resume_template(target_gtid, flag);
1626 }
1627 void __kmp_resume_oncore(int target_gtid, kmp_flag_oncore *flag) {
1628   __kmp_resume_template(target_gtid, flag);
1629 }
1630 
1631 #if KMP_USE_MONITOR
1632 void __kmp_resume_monitor() {
1633   KMP_TIME_DEVELOPER_PARTITIONED_BLOCK(USER_resume);
1634   int status;
1635 #ifdef KMP_DEBUG
1636   int gtid = TCR_4(__kmp_init_gtid) ? __kmp_get_gtid() : -1;
1637   KF_TRACE(30, ("__kmp_resume_monitor: T#%d wants to wakeup T#%d enter\n", gtid,
1638                 KMP_GTID_MONITOR));
1639   KMP_DEBUG_ASSERT(gtid != KMP_GTID_MONITOR);
1640 #endif
1641   status = pthread_mutex_lock(&__kmp_wait_mx.m_mutex);
1642   KMP_CHECK_SYSFAIL("pthread_mutex_lock", status);
1643 #ifdef DEBUG_SUSPEND
1644   {
1645     char buffer[128];
1646     __kmp_print_cond(buffer, &__kmp_wait_cv.c_cond);
1647     __kmp_printf("__kmp_resume_monitor: T#%d resuming T#%d: %s\n", gtid,
1648                  KMP_GTID_MONITOR, buffer);
1649   }
1650 #endif
1651   status = pthread_cond_signal(&__kmp_wait_cv.c_cond);
1652   KMP_CHECK_SYSFAIL("pthread_cond_signal", status);
1653   status = pthread_mutex_unlock(&__kmp_wait_mx.m_mutex);
1654   KMP_CHECK_SYSFAIL("pthread_mutex_unlock", status);
1655   KF_TRACE(30, ("__kmp_resume_monitor: T#%d exiting after signaling wake up"
1656                 " for T#%d\n",
1657                 gtid, KMP_GTID_MONITOR));
1658 }
1659 #endif // KMP_USE_MONITOR
1660 
1661 void __kmp_yield(int cond) {
1662   if (!cond)
1663     return;
1664 #if KMP_USE_MONITOR
1665   if (!__kmp_yielding_on)
1666     return;
1667 #else
1668   if (__kmp_yield_cycle && !KMP_YIELD_NOW())
1669     return;
1670 #endif
1671   sched_yield();
1672 }
1673 
1674 void __kmp_gtid_set_specific(int gtid) {
1675   if (__kmp_init_gtid) {
1676     int status;
1677     status = pthread_setspecific(__kmp_gtid_threadprivate_key,
1678                                  (void *)(intptr_t)(gtid + 1));
1679     KMP_CHECK_SYSFAIL("pthread_setspecific", status);
1680   } else {
1681     KA_TRACE(50, ("__kmp_gtid_set_specific: runtime shutdown, returning\n"));
1682   }
1683 }
1684 
1685 int __kmp_gtid_get_specific() {
1686   int gtid;
1687   if (!__kmp_init_gtid) {
1688     KA_TRACE(50, ("__kmp_gtid_get_specific: runtime shutdown, returning "
1689                   "KMP_GTID_SHUTDOWN\n"));
1690     return KMP_GTID_SHUTDOWN;
1691   }
1692   gtid = (int)(size_t)pthread_getspecific(__kmp_gtid_threadprivate_key);
1693   if (gtid == 0) {
1694     gtid = KMP_GTID_DNE;
1695   } else {
1696     gtid--;
1697   }
1698   KA_TRACE(50, ("__kmp_gtid_get_specific: key:%d gtid:%d\n",
1699                 __kmp_gtid_threadprivate_key, gtid));
1700   return gtid;
1701 }
1702 
1703 double __kmp_read_cpu_time(void) {
1704   /*clock_t   t;*/
1705   struct tms buffer;
1706 
1707   /*t =*/times(&buffer);
1708 
1709   return (buffer.tms_utime + buffer.tms_cutime) / (double)CLOCKS_PER_SEC;
1710 }
1711 
1712 int __kmp_read_system_info(struct kmp_sys_info *info) {
1713   int status;
1714   struct rusage r_usage;
1715 
1716   memset(info, 0, sizeof(*info));
1717 
1718   status = getrusage(RUSAGE_SELF, &r_usage);
1719   KMP_CHECK_SYSFAIL_ERRNO("getrusage", status);
1720 
1721   // The maximum resident set size utilized (in kilobytes)
1722   info->maxrss = r_usage.ru_maxrss;
1723   // The number of page faults serviced without any I/O
1724   info->minflt = r_usage.ru_minflt;
1725   // The number of page faults serviced that required I/O
1726   info->majflt = r_usage.ru_majflt;
1727   // The number of times a process was "swapped" out of memory
1728   info->nswap = r_usage.ru_nswap;
1729   // The number of times the file system had to perform input
1730   info->inblock = r_usage.ru_inblock;
1731   // The number of times the file system had to perform output
1732   info->oublock = r_usage.ru_oublock;
1733   // The number of times a context switch was voluntarily
1734   info->nvcsw = r_usage.ru_nvcsw;
1735   // The number of times a context switch was forced
1736   info->nivcsw = r_usage.ru_nivcsw;
1737 
1738   return (status != 0);
1739 }
1740 
1741 void __kmp_read_system_time(double *delta) {
1742   double t_ns;
1743   struct timeval tval;
1744   struct timespec stop;
1745   int status;
1746 
1747   status = gettimeofday(&tval, NULL);
1748   KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1749   TIMEVAL_TO_TIMESPEC(&tval, &stop);
1750   t_ns = TS2NS(stop) - TS2NS(__kmp_sys_timer_data.start);
1751   *delta = (t_ns * 1e-9);
1752 }
1753 
1754 void __kmp_clear_system_time(void) {
1755   struct timeval tval;
1756   int status;
1757   status = gettimeofday(&tval, NULL);
1758   KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1759   TIMEVAL_TO_TIMESPEC(&tval, &__kmp_sys_timer_data.start);
1760 }
1761 
1762 #ifdef BUILD_TV
1763 
1764 void __kmp_tv_threadprivate_store(kmp_info_t *th, void *global_addr,
1765                                   void *thread_addr) {
1766   struct tv_data *p;
1767 
1768   p = (struct tv_data *)__kmp_allocate(sizeof(*p));
1769 
1770   p->u.tp.global_addr = global_addr;
1771   p->u.tp.thread_addr = thread_addr;
1772 
1773   p->type = (void *)1;
1774 
1775   p->next = th->th.th_local.tv_data;
1776   th->th.th_local.tv_data = p;
1777 
1778   if (p->next == 0) {
1779     int rc = pthread_setspecific(__kmp_tv_key, p);
1780     KMP_CHECK_SYSFAIL("pthread_setspecific", rc);
1781   }
1782 }
1783 
1784 #endif /* BUILD_TV */
1785 
1786 static int __kmp_get_xproc(void) {
1787 
1788   int r = 0;
1789 
1790 #if KMP_OS_LINUX || KMP_OS_FREEBSD || KMP_OS_NETBSD
1791 
1792   r = sysconf(_SC_NPROCESSORS_ONLN);
1793 
1794 #elif KMP_OS_DARWIN
1795 
1796   // Bug C77011 High "OpenMP Threads and number of active cores".
1797 
1798   // Find the number of available CPUs.
1799   kern_return_t rc;
1800   host_basic_info_data_t info;
1801   mach_msg_type_number_t num = HOST_BASIC_INFO_COUNT;
1802   rc = host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&info, &num);
1803   if (rc == 0 && num == HOST_BASIC_INFO_COUNT) {
1804     // Cannot use KA_TRACE() here because this code works before trace support
1805     // is initialized.
1806     r = info.avail_cpus;
1807   } else {
1808     KMP_WARNING(CantGetNumAvailCPU);
1809     KMP_INFORM(AssumedNumCPU);
1810   }; // if
1811 
1812 #else
1813 
1814 #error "Unknown or unsupported OS."
1815 
1816 #endif
1817 
1818   return r > 0 ? r : 2; /* guess value of 2 if OS told us 0 */
1819 
1820 } // __kmp_get_xproc
1821 
1822 int __kmp_read_from_file(char const *path, char const *format, ...) {
1823   int result;
1824   va_list args;
1825 
1826   va_start(args, format);
1827   FILE *f = fopen(path, "rb");
1828   if (f == NULL)
1829     return 0;
1830   result = vfscanf(f, format, args);
1831   fclose(f);
1832 
1833   return result;
1834 }
1835 
1836 void __kmp_runtime_initialize(void) {
1837   int status;
1838   pthread_mutexattr_t mutex_attr;
1839   pthread_condattr_t cond_attr;
1840 
1841   if (__kmp_init_runtime) {
1842     return;
1843   }; // if
1844 
1845 #if (KMP_ARCH_X86 || KMP_ARCH_X86_64)
1846   if (!__kmp_cpuinfo.initialized) {
1847     __kmp_query_cpuid(&__kmp_cpuinfo);
1848   }; // if
1849 #endif /* KMP_ARCH_X86 || KMP_ARCH_X86_64 */
1850 
1851   __kmp_xproc = __kmp_get_xproc();
1852 
1853   if (sysconf(_SC_THREADS)) {
1854 
1855     /* Query the maximum number of threads */
1856     __kmp_sys_max_nth = sysconf(_SC_THREAD_THREADS_MAX);
1857     if (__kmp_sys_max_nth == -1) {
1858       /* Unlimited threads for NPTL */
1859       __kmp_sys_max_nth = INT_MAX;
1860     } else if (__kmp_sys_max_nth <= 1) {
1861       /* Can't tell, just use PTHREAD_THREADS_MAX */
1862       __kmp_sys_max_nth = KMP_MAX_NTH;
1863     }
1864 
1865     /* Query the minimum stack size */
1866     __kmp_sys_min_stksize = sysconf(_SC_THREAD_STACK_MIN);
1867     if (__kmp_sys_min_stksize <= 1) {
1868       __kmp_sys_min_stksize = KMP_MIN_STKSIZE;
1869     }
1870   }
1871 
1872   /* Set up minimum number of threads to switch to TLS gtid */
1873   __kmp_tls_gtid_min = KMP_TLS_GTID_MIN;
1874 
1875 #ifdef BUILD_TV
1876   {
1877     int rc = pthread_key_create(&__kmp_tv_key, 0);
1878     KMP_CHECK_SYSFAIL("pthread_key_create", rc);
1879   }
1880 #endif
1881 
1882   status = pthread_key_create(&__kmp_gtid_threadprivate_key,
1883                               __kmp_internal_end_dest);
1884   KMP_CHECK_SYSFAIL("pthread_key_create", status);
1885   status = pthread_mutexattr_init(&mutex_attr);
1886   KMP_CHECK_SYSFAIL("pthread_mutexattr_init", status);
1887   status = pthread_mutex_init(&__kmp_wait_mx.m_mutex, &mutex_attr);
1888   KMP_CHECK_SYSFAIL("pthread_mutex_init", status);
1889   status = pthread_condattr_init(&cond_attr);
1890   KMP_CHECK_SYSFAIL("pthread_condattr_init", status);
1891   status = pthread_cond_init(&__kmp_wait_cv.c_cond, &cond_attr);
1892   KMP_CHECK_SYSFAIL("pthread_cond_init", status);
1893 #if USE_ITT_BUILD
1894   __kmp_itt_initialize();
1895 #endif /* USE_ITT_BUILD */
1896 
1897   __kmp_init_runtime = TRUE;
1898 }
1899 
1900 void __kmp_runtime_destroy(void) {
1901   int status;
1902 
1903   if (!__kmp_init_runtime) {
1904     return; // Nothing to do.
1905   };
1906 
1907 #if USE_ITT_BUILD
1908   __kmp_itt_destroy();
1909 #endif /* USE_ITT_BUILD */
1910 
1911   status = pthread_key_delete(__kmp_gtid_threadprivate_key);
1912   KMP_CHECK_SYSFAIL("pthread_key_delete", status);
1913 #ifdef BUILD_TV
1914   status = pthread_key_delete(__kmp_tv_key);
1915   KMP_CHECK_SYSFAIL("pthread_key_delete", status);
1916 #endif
1917 
1918   status = pthread_mutex_destroy(&__kmp_wait_mx.m_mutex);
1919   if (status != 0 && status != EBUSY) {
1920     KMP_SYSFAIL("pthread_mutex_destroy", status);
1921   }
1922   status = pthread_cond_destroy(&__kmp_wait_cv.c_cond);
1923   if (status != 0 && status != EBUSY) {
1924     KMP_SYSFAIL("pthread_cond_destroy", status);
1925   }
1926 #if KMP_AFFINITY_SUPPORTED
1927   __kmp_affinity_uninitialize();
1928 #endif
1929 
1930   __kmp_init_runtime = FALSE;
1931 }
1932 
1933 /* Put the thread to sleep for a time period */
1934 /* NOTE: not currently used anywhere */
1935 void __kmp_thread_sleep(int millis) { sleep((millis + 500) / 1000); }
1936 
1937 /* Calculate the elapsed wall clock time for the user */
1938 void __kmp_elapsed(double *t) {
1939   int status;
1940 #ifdef FIX_SGI_CLOCK
1941   struct timespec ts;
1942 
1943   status = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
1944   KMP_CHECK_SYSFAIL_ERRNO("clock_gettime", status);
1945   *t =
1946       (double)ts.tv_nsec * (1.0 / (double)KMP_NSEC_PER_SEC) + (double)ts.tv_sec;
1947 #else
1948   struct timeval tv;
1949 
1950   status = gettimeofday(&tv, NULL);
1951   KMP_CHECK_SYSFAIL_ERRNO("gettimeofday", status);
1952   *t =
1953       (double)tv.tv_usec * (1.0 / (double)KMP_USEC_PER_SEC) + (double)tv.tv_sec;
1954 #endif
1955 }
1956 
1957 /* Calculate the elapsed wall clock tick for the user */
1958 void __kmp_elapsed_tick(double *t) { *t = 1 / (double)CLOCKS_PER_SEC; }
1959 
1960 /* Return the current time stamp in nsec */
1961 kmp_uint64 __kmp_now_nsec() {
1962   struct timeval t;
1963   gettimeofday(&t, NULL);
1964   return KMP_NSEC_PER_SEC * t.tv_sec + 1000 * t.tv_usec;
1965 }
1966 
1967 #if KMP_ARCH_X86 || KMP_ARCH_X86_64
1968 /* Measure clock ticks per millisecond */
1969 void __kmp_initialize_system_tick() {
1970   kmp_uint64 delay = 100000; // 50~100 usec on most machines.
1971   kmp_uint64 nsec = __kmp_now_nsec();
1972   kmp_uint64 goal = __kmp_hardware_timestamp() + delay;
1973   kmp_uint64 now;
1974   while ((now = __kmp_hardware_timestamp()) < goal)
1975     ;
1976   __kmp_ticks_per_msec =
1977       (kmp_uint64)(1e6 * (delay + (now - goal)) / (__kmp_now_nsec() - nsec));
1978 }
1979 #endif
1980 
1981 /* Determine whether the given address is mapped into the current address
1982    space. */
1983 
1984 int __kmp_is_address_mapped(void *addr) {
1985 
1986   int found = 0;
1987   int rc;
1988 
1989 #if KMP_OS_LINUX || KMP_OS_FREEBSD
1990 
1991   /* On Linux* OS, read the /proc/<pid>/maps pseudo-file to get all the address
1992      ranges mapped into the address space. */
1993 
1994   char *name = __kmp_str_format("/proc/%d/maps", getpid());
1995   FILE *file = NULL;
1996 
1997   file = fopen(name, "r");
1998   KMP_ASSERT(file != NULL);
1999 
2000   for (;;) {
2001 
2002     void *beginning = NULL;
2003     void *ending = NULL;
2004     char perms[5];
2005 
2006     rc = fscanf(file, "%p-%p %4s %*[^\n]\n", &beginning, &ending, perms);
2007     if (rc == EOF) {
2008       break;
2009     }; // if
2010     KMP_ASSERT(rc == 3 &&
2011                KMP_STRLEN(perms) == 4); // Make sure all fields are read.
2012 
2013     // Ending address is not included in the region, but beginning is.
2014     if ((addr >= beginning) && (addr < ending)) {
2015       perms[2] = 0; // 3th and 4th character does not matter.
2016       if (strcmp(perms, "rw") == 0) {
2017         // Memory we are looking for should be readable and writable.
2018         found = 1;
2019       }; // if
2020       break;
2021     }; // if
2022 
2023   }; // forever
2024 
2025   // Free resources.
2026   fclose(file);
2027   KMP_INTERNAL_FREE(name);
2028 
2029 #elif KMP_OS_DARWIN
2030 
2031   /* On OS X*, /proc pseudo filesystem is not available. Try to read memory
2032      using vm interface. */
2033 
2034   int buffer;
2035   vm_size_t count;
2036   rc = vm_read_overwrite(
2037       mach_task_self(), // Task to read memory of.
2038       (vm_address_t)(addr), // Address to read from.
2039       1, // Number of bytes to be read.
2040       (vm_address_t)(&buffer), // Address of buffer to save read bytes in.
2041       &count // Address of var to save number of read bytes in.
2042       );
2043   if (rc == 0) {
2044     // Memory successfully read.
2045     found = 1;
2046   }; // if
2047 
2048 #elif KMP_OS_FREEBSD || KMP_OS_NETBSD
2049 
2050   // FIXME(FreeBSD, NetBSD): Implement this
2051   found = 1;
2052 
2053 #else
2054 
2055 #error "Unknown or unsupported OS"
2056 
2057 #endif
2058 
2059   return found;
2060 
2061 } // __kmp_is_address_mapped
2062 
2063 #ifdef USE_LOAD_BALANCE
2064 
2065 #if KMP_OS_DARWIN
2066 
2067 // The function returns the rounded value of the system load average
2068 // during given time interval which depends on the value of
2069 // __kmp_load_balance_interval variable (default is 60 sec, other values
2070 // may be 300 sec or 900 sec).
2071 // It returns -1 in case of error.
2072 int __kmp_get_load_balance(int max) {
2073   double averages[3];
2074   int ret_avg = 0;
2075 
2076   int res = getloadavg(averages, 3);
2077 
2078   // Check __kmp_load_balance_interval to determine which of averages to use.
2079   // getloadavg() may return the number of samples less than requested that is
2080   // less than 3.
2081   if (__kmp_load_balance_interval < 180 && (res >= 1)) {
2082     ret_avg = averages[0]; // 1 min
2083   } else if ((__kmp_load_balance_interval >= 180 &&
2084               __kmp_load_balance_interval < 600) &&
2085              (res >= 2)) {
2086     ret_avg = averages[1]; // 5 min
2087   } else if ((__kmp_load_balance_interval >= 600) && (res == 3)) {
2088     ret_avg = averages[2]; // 15 min
2089   } else { // Error occurred
2090     return -1;
2091   }
2092 
2093   return ret_avg;
2094 }
2095 
2096 #else // Linux* OS
2097 
2098 // The fuction returns number of running (not sleeping) threads, or -1 in case
2099 // of error. Error could be reported if Linux* OS kernel too old (without
2100 // "/proc" support). Counting running threads stops if max running threads
2101 // encountered.
2102 int __kmp_get_load_balance(int max) {
2103   static int permanent_error = 0;
2104   static int glb_running_threads = 0; // Saved count of the running threads for
2105   // the thread balance algortihm
2106   static double glb_call_time = 0; /* Thread balance algorithm call time */
2107 
2108   int running_threads = 0; // Number of running threads in the system.
2109 
2110   DIR *proc_dir = NULL; // Handle of "/proc/" directory.
2111   struct dirent *proc_entry = NULL;
2112 
2113   kmp_str_buf_t task_path; // "/proc/<pid>/task/<tid>/" path.
2114   DIR *task_dir = NULL; // Handle of "/proc/<pid>/task/<tid>/" directory.
2115   struct dirent *task_entry = NULL;
2116   int task_path_fixed_len;
2117 
2118   kmp_str_buf_t stat_path; // "/proc/<pid>/task/<tid>/stat" path.
2119   int stat_file = -1;
2120   int stat_path_fixed_len;
2121 
2122   int total_processes = 0; // Total number of processes in system.
2123   int total_threads = 0; // Total number of threads in system.
2124 
2125   double call_time = 0.0;
2126 
2127   __kmp_str_buf_init(&task_path);
2128   __kmp_str_buf_init(&stat_path);
2129 
2130   __kmp_elapsed(&call_time);
2131 
2132   if (glb_call_time &&
2133       (call_time - glb_call_time < __kmp_load_balance_interval)) {
2134     running_threads = glb_running_threads;
2135     goto finish;
2136   }
2137 
2138   glb_call_time = call_time;
2139 
2140   // Do not spend time on scanning "/proc/" if we have a permanent error.
2141   if (permanent_error) {
2142     running_threads = -1;
2143     goto finish;
2144   }; // if
2145 
2146   if (max <= 0) {
2147     max = INT_MAX;
2148   }; // if
2149 
2150   // Open "/proc/" directory.
2151   proc_dir = opendir("/proc");
2152   if (proc_dir == NULL) {
2153     // Cannot open "/prroc/". Probably the kernel does not support it. Return an
2154     // error now and in subsequent calls.
2155     running_threads = -1;
2156     permanent_error = 1;
2157     goto finish;
2158   }; // if
2159 
2160   // Initialize fixed part of task_path. This part will not change.
2161   __kmp_str_buf_cat(&task_path, "/proc/", 6);
2162   task_path_fixed_len = task_path.used; // Remember number of used characters.
2163 
2164   proc_entry = readdir(proc_dir);
2165   while (proc_entry != NULL) {
2166     // Proc entry is a directory and name starts with a digit. Assume it is a
2167     // process' directory.
2168     if (proc_entry->d_type == DT_DIR && isdigit(proc_entry->d_name[0])) {
2169 
2170       ++total_processes;
2171       // Make sure init process is the very first in "/proc", so we can replace
2172       // strcmp( proc_entry->d_name, "1" ) == 0 with simpler total_processes ==
2173       // 1. We are going to check that total_processes == 1 => d_name == "1" is
2174       // true (where "=>" is implication). Since C++ does not have => operator,
2175       // let us replace it with its equivalent: a => b == ! a || b.
2176       KMP_DEBUG_ASSERT(total_processes != 1 ||
2177                        strcmp(proc_entry->d_name, "1") == 0);
2178 
2179       // Construct task_path.
2180       task_path.used = task_path_fixed_len; // Reset task_path to "/proc/".
2181       __kmp_str_buf_cat(&task_path, proc_entry->d_name,
2182                         KMP_STRLEN(proc_entry->d_name));
2183       __kmp_str_buf_cat(&task_path, "/task", 5);
2184 
2185       task_dir = opendir(task_path.str);
2186       if (task_dir == NULL) {
2187         // Process can finish between reading "/proc/" directory entry and
2188         // opening process' "task/" directory. So, in general case we should not
2189         // complain, but have to skip this process and read the next one. But on
2190         // systems with no "task/" support we will spend lot of time to scan
2191         // "/proc/" tree again and again without any benefit. "init" process
2192         // (its pid is 1) should exist always, so, if we cannot open
2193         // "/proc/1/task/" directory, it means "task/" is not supported by
2194         // kernel. Report an error now and in the future.
2195         if (strcmp(proc_entry->d_name, "1") == 0) {
2196           running_threads = -1;
2197           permanent_error = 1;
2198           goto finish;
2199         }; // if
2200       } else {
2201         // Construct fixed part of stat file path.
2202         __kmp_str_buf_clear(&stat_path);
2203         __kmp_str_buf_cat(&stat_path, task_path.str, task_path.used);
2204         __kmp_str_buf_cat(&stat_path, "/", 1);
2205         stat_path_fixed_len = stat_path.used;
2206 
2207         task_entry = readdir(task_dir);
2208         while (task_entry != NULL) {
2209           // It is a directory and name starts with a digit.
2210           if (proc_entry->d_type == DT_DIR && isdigit(task_entry->d_name[0])) {
2211             ++total_threads;
2212 
2213             // Consruct complete stat file path. Easiest way would be:
2214             //  __kmp_str_buf_print( & stat_path, "%s/%s/stat", task_path.str,
2215             //  task_entry->d_name );
2216             // but seriae of __kmp_str_buf_cat works a bit faster.
2217             stat_path.used =
2218                 stat_path_fixed_len; // Reset stat path to its fixed part.
2219             __kmp_str_buf_cat(&stat_path, task_entry->d_name,
2220                               KMP_STRLEN(task_entry->d_name));
2221             __kmp_str_buf_cat(&stat_path, "/stat", 5);
2222 
2223             // Note: Low-level API (open/read/close) is used. High-level API
2224             // (fopen/fclose)  works ~ 30 % slower.
2225             stat_file = open(stat_path.str, O_RDONLY);
2226             if (stat_file == -1) {
2227               // We cannot report an error because task (thread) can terminate
2228               // just before reading this file.
2229             } else {
2230               /* Content of "stat" file looks like:
2231                  24285 (program) S ...
2232 
2233                  It is a single line (if program name does not include funny
2234                  symbols). First number is a thread id, then name of executable
2235                  file name in paretheses, then state of the thread. We need just
2236                  thread state.
2237 
2238                  Good news: Length of program name is 15 characters max. Longer
2239                  names are truncated.
2240 
2241                  Thus, we need rather short buffer: 15 chars for program name +
2242                  2 parenthesis, + 3 spaces + ~7 digits of pid = 37.
2243 
2244                  Bad news: Program name may contain special symbols like space,
2245                  closing parenthesis, or even new line. This makes parsing
2246                  "stat" file not 100 % reliable. In case of fanny program names
2247                  parsing may fail (report incorrect thread state).
2248 
2249                  Parsing "status" file looks more promissing (due to different
2250                  file structure and escaping special symbols) but reading and
2251                  parsing of "status" file works slower.
2252                   -- ln
2253               */
2254               char buffer[65];
2255               int len;
2256               len = read(stat_file, buffer, sizeof(buffer) - 1);
2257               if (len >= 0) {
2258                 buffer[len] = 0;
2259                 // Using scanf:
2260                 //     sscanf( buffer, "%*d (%*s) %c ", & state );
2261                 // looks very nice, but searching for a closing parenthesis
2262                 // works a bit faster.
2263                 char *close_parent = strstr(buffer, ") ");
2264                 if (close_parent != NULL) {
2265                   char state = *(close_parent + 2);
2266                   if (state == 'R') {
2267                     ++running_threads;
2268                     if (running_threads >= max) {
2269                       goto finish;
2270                     }; // if
2271                   }; // if
2272                 }; // if
2273               }; // if
2274               close(stat_file);
2275               stat_file = -1;
2276             }; // if
2277           }; // if
2278           task_entry = readdir(task_dir);
2279         }; // while
2280         closedir(task_dir);
2281         task_dir = NULL;
2282       }; // if
2283     }; // if
2284     proc_entry = readdir(proc_dir);
2285   }; // while
2286 
2287   // There _might_ be a timing hole where the thread executing this
2288   // code get skipped in the load balance, and running_threads is 0.
2289   // Assert in the debug builds only!!!
2290   KMP_DEBUG_ASSERT(running_threads > 0);
2291   if (running_threads <= 0) {
2292     running_threads = 1;
2293   }
2294 
2295 finish: // Clean up and exit.
2296   if (proc_dir != NULL) {
2297     closedir(proc_dir);
2298   }; // if
2299   __kmp_str_buf_free(&task_path);
2300   if (task_dir != NULL) {
2301     closedir(task_dir);
2302   }; // if
2303   __kmp_str_buf_free(&stat_path);
2304   if (stat_file != -1) {
2305     close(stat_file);
2306   }; // if
2307 
2308   glb_running_threads = running_threads;
2309 
2310   return running_threads;
2311 
2312 } // __kmp_get_load_balance
2313 
2314 #endif // KMP_OS_DARWIN
2315 
2316 #endif // USE_LOAD_BALANCE
2317 
2318 #if !(KMP_ARCH_X86 || KMP_ARCH_X86_64 || KMP_MIC ||                            \
2319       ((KMP_OS_LINUX || KMP_OS_DARWIN) && KMP_ARCH_AARCH64) || KMP_ARCH_PPC64)
2320 
2321 // we really only need the case with 1 argument, because CLANG always build
2322 // a struct of pointers to shared variables referenced in the outlined function
2323 int __kmp_invoke_microtask(microtask_t pkfn, int gtid, int tid, int argc,
2324                            void *p_argv[]
2325 #if OMPT_SUPPORT
2326                            ,
2327                            void **exit_frame_ptr
2328 #endif
2329                            ) {
2330 #if OMPT_SUPPORT
2331   *exit_frame_ptr = __builtin_frame_address(0);
2332 #endif
2333 
2334   switch (argc) {
2335   default:
2336     fprintf(stderr, "Too many args to microtask: %d!\n", argc);
2337     fflush(stderr);
2338     exit(-1);
2339   case 0:
2340     (*pkfn)(&gtid, &tid);
2341     break;
2342   case 1:
2343     (*pkfn)(&gtid, &tid, p_argv[0]);
2344     break;
2345   case 2:
2346     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1]);
2347     break;
2348   case 3:
2349     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2]);
2350     break;
2351   case 4:
2352     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3]);
2353     break;
2354   case 5:
2355     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4]);
2356     break;
2357   case 6:
2358     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2359             p_argv[5]);
2360     break;
2361   case 7:
2362     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2363             p_argv[5], p_argv[6]);
2364     break;
2365   case 8:
2366     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2367             p_argv[5], p_argv[6], p_argv[7]);
2368     break;
2369   case 9:
2370     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2371             p_argv[5], p_argv[6], p_argv[7], p_argv[8]);
2372     break;
2373   case 10:
2374     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2375             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9]);
2376     break;
2377   case 11:
2378     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2379             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10]);
2380     break;
2381   case 12:
2382     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2383             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2384             p_argv[11]);
2385     break;
2386   case 13:
2387     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2388             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2389             p_argv[11], p_argv[12]);
2390     break;
2391   case 14:
2392     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2393             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2394             p_argv[11], p_argv[12], p_argv[13]);
2395     break;
2396   case 15:
2397     (*pkfn)(&gtid, &tid, p_argv[0], p_argv[1], p_argv[2], p_argv[3], p_argv[4],
2398             p_argv[5], p_argv[6], p_argv[7], p_argv[8], p_argv[9], p_argv[10],
2399             p_argv[11], p_argv[12], p_argv[13], p_argv[14]);
2400     break;
2401   }
2402 
2403 #if OMPT_SUPPORT
2404   *exit_frame_ptr = 0;
2405 #endif
2406 
2407   return 1;
2408 }
2409 
2410 #endif
2411 
2412 // end of file //
2413