1 /** @file kmp_stats.cpp
2  * Statistics gathering and processing.
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 #include "kmp.h"
16 #include "kmp_str.h"
17 #include "kmp_lock.h"
18 #include "kmp_stats.h"
19 
20 #include <algorithm>
21 #include <sstream>
22 #include <iomanip>
23 #include <stdlib.h>                             // for atexit
24 #include <ctime>
25 
26 #define STRINGIZE2(x) #x
27 #define STRINGIZE(x) STRINGIZE2(x)
28 
29 #define expandName(name,flags,ignore)  {STRINGIZE(name),flags},
30 statInfo timeStat::timerInfo[] = {
31     KMP_FOREACH_TIMER(expandName,0)
32     {0,0}
33 };
34 const statInfo counter::counterInfo[] = {
35     KMP_FOREACH_COUNTER(expandName,0)
36     {0,0}
37 };
38 #undef expandName
39 
40 #define expandName(ignore1,ignore2,ignore3)  {0.0,0.0,0.0},
41 kmp_stats_output_module::rgb_color kmp_stats_output_module::timerColorInfo[] = {
42     KMP_FOREACH_TIMER(expandName,0)
43     {0.0,0.0,0.0}
44 };
45 #undef expandName
46 
47 const kmp_stats_output_module::rgb_color kmp_stats_output_module::globalColorArray[] = {
48     {1.0, 0.0, 0.0}, // red
49     {1.0, 0.6, 0.0}, // orange
50     {1.0, 1.0, 0.0}, // yellow
51     {0.0, 1.0, 0.0}, // green
52     {0.0, 0.0, 1.0}, // blue
53     {0.6, 0.2, 0.8}, // purple
54     {1.0, 0.0, 1.0}, // magenta
55     {0.0, 0.4, 0.2}, // dark green
56     {1.0, 1.0, 0.6}, // light yellow
57     {0.6, 0.4, 0.6}, // dirty purple
58     {0.0, 1.0, 1.0}, // cyan
59     {1.0, 0.4, 0.8}, // pink
60     {0.5, 0.5, 0.5}, // grey
61     {0.8, 0.7, 0.5}, // brown
62     {0.6, 0.6, 1.0}, // light blue
63     {1.0, 0.7, 0.5}, // peach
64     {0.8, 0.5, 1.0}, // lavender
65     {0.6, 0.0, 0.0}, // dark red
66     {0.7, 0.6, 0.0}, // gold
67     {0.0, 0.0, 0.0}  // black
68 };
69 
70 // Ensure that the atexit handler only runs once.
71 static uint32_t statsPrinted = 0;
72 
73 // output interface
74 static kmp_stats_output_module __kmp_stats_global_output;
75 
76 /* ****************************************************** */
77 /* ************* statistic member functions ************* */
78 
79 void statistic::addSample(double sample)
80 {
81     double delta = sample - meanVal;
82 
83     sampleCount = sampleCount + 1;
84     meanVal     = meanVal + delta/sampleCount;
85     m2          = m2 + delta*(sample - meanVal);
86 
87     minVal = std::min(minVal, sample);
88     maxVal = std::max(maxVal, sample);
89 }
90 
91 statistic & statistic::operator+= (const statistic & other)
92 {
93     if (sampleCount == 0)
94     {
95         *this = other;
96         return *this;
97     }
98 
99     uint64_t newSampleCount = sampleCount + other.sampleCount;
100     double dnsc  = double(newSampleCount);
101     double dsc   = double(sampleCount);
102     double dscBydnsc = dsc/dnsc;
103     double dosc  = double(other.sampleCount);
104     double delta = other.meanVal - meanVal;
105 
106     // Try to order these calculations to avoid overflows.
107     // If this were Fortran, then the compiler would not be able to re-order over brackets.
108     // In C++ it may be legal to do that (we certainly hope it doesn't, and CC+ Programming Language 2nd edition
109     // suggests it shouldn't, since it says that exploitation of associativity can only be made if the operation
110     // really is associative (which floating addition isn't...)).
111     meanVal     = meanVal*dscBydnsc + other.meanVal*(1-dscBydnsc);
112     m2          = m2 + other.m2 + dscBydnsc*dosc*delta*delta;
113     minVal      = std::min (minVal, other.minVal);
114     maxVal      = std::max (maxVal, other.maxVal);
115     sampleCount = newSampleCount;
116 
117 
118     return *this;
119 }
120 
121 void statistic::scale(double factor)
122 {
123     minVal = minVal*factor;
124     maxVal = maxVal*factor;
125     meanVal= meanVal*factor;
126     m2     = m2*factor*factor;
127     return;
128 }
129 
130 std::string statistic::format(char unit, bool total) const
131 {
132     std::string result = formatSI(sampleCount,9,' ');
133 
134     if (sampleCount == 0)
135     {
136         result = result + std::string(", ") + formatSI(0.0, 9, unit);
137         result = result + std::string(", ") + formatSI(0.0, 9, unit);
138         result = result + std::string(", ") + formatSI(0.0, 9, unit);
139         if (total)
140             result = result + std::string(", ") + formatSI(0.0, 9, unit);
141         result = result + std::string(", ") + formatSI(0.0, 9, unit);
142     }
143     else
144     {
145         result = result + std::string(", ") + formatSI(minVal,  9, unit);
146         result = result + std::string(", ") + formatSI(meanVal, 9, unit);
147         result = result + std::string(", ") + formatSI(maxVal,  9, unit);
148         if (total)
149             result = result + std::string(", ") + formatSI(meanVal*sampleCount, 9, unit);
150         result = result + std::string(", ") + formatSI(getSD(), 9, unit);
151     }
152     return result;
153 }
154 
155 /* ********************************************************** */
156 /* ************* explicitTimer member functions ************* */
157 
158 void explicitTimer::start(timer_e timerEnumValue) {
159     startTime = tsc_tick_count::now();
160     if(timeStat::logEvent(timerEnumValue)) {
161         __kmp_stats_thread_ptr->incrementNestValue();
162     }
163     return;
164 }
165 
166 void explicitTimer::stop(timer_e timerEnumValue) {
167     if (startTime.getValue() == 0)
168         return;
169 
170     tsc_tick_count finishTime = tsc_tick_count::now();
171 
172     //stat->addSample ((tsc_tick_count::now() - startTime).ticks());
173     stat->addSample ((finishTime - startTime).ticks());
174 
175     if(timeStat::logEvent(timerEnumValue)) {
176         __kmp_stats_thread_ptr->push_event(startTime.getValue() - __kmp_stats_start_time.getValue(), finishTime.getValue() - __kmp_stats_start_time.getValue(), __kmp_stats_thread_ptr->getNestValue(), timerEnumValue);
177         __kmp_stats_thread_ptr->decrementNestValue();
178     }
179 
180     /* We accept the risk that we drop a sample because it really did start at t==0. */
181     startTime = 0;
182     return;
183 }
184 
185 /* ******************************************************************* */
186 /* ************* kmp_stats_event_vector member functions ************* */
187 
188 void kmp_stats_event_vector::deallocate() {
189     __kmp_free(events);
190     internal_size = 0;
191     allocated_size = 0;
192     events = NULL;
193 }
194 
195 // This function is for qsort() which requires the compare function to return
196 // either a negative number if event1 < event2, a positive number if event1 > event2
197 // or zero if event1 == event2.
198 // This sorts by start time (lowest to highest).
199 int compare_two_events(const void* event1, const void* event2) {
200     kmp_stats_event* ev1 = (kmp_stats_event*)event1;
201     kmp_stats_event* ev2 = (kmp_stats_event*)event2;
202 
203     if(ev1->getStart() < ev2->getStart()) return -1;
204     else if(ev1->getStart() > ev2->getStart()) return 1;
205     else return 0;
206 }
207 
208 void kmp_stats_event_vector::sort() {
209     qsort(events, internal_size, sizeof(kmp_stats_event), compare_two_events);
210 }
211 
212 /* *********************************************************** */
213 /* ************* kmp_stats_list member functions ************* */
214 
215 // returns a pointer to newly created stats node
216 kmp_stats_list* kmp_stats_list::push_back(int gtid) {
217     kmp_stats_list* newnode = (kmp_stats_list*)__kmp_allocate(sizeof(kmp_stats_list));
218     // placement new, only requires space and pointer and initializes (so __kmp_allocate instead of C++ new[] is used)
219     new (newnode) kmp_stats_list();
220     newnode->setGtid(gtid);
221     newnode->prev = this->prev;
222     newnode->next = this;
223     newnode->prev->next = newnode;
224     newnode->next->prev = newnode;
225     return newnode;
226 }
227 void kmp_stats_list::deallocate() {
228     kmp_stats_list* ptr = this->next;
229     kmp_stats_list* delptr = this->next;
230     while(ptr != this) {
231         delptr = ptr;
232         ptr=ptr->next;
233         // placement new means we have to explicitly call destructor.
234         delptr->_event_vector.deallocate();
235         delptr->~kmp_stats_list();
236         __kmp_free(delptr);
237     }
238 }
239 kmp_stats_list::iterator kmp_stats_list::begin() {
240     kmp_stats_list::iterator it;
241     it.ptr = this->next;
242     return it;
243 }
244 kmp_stats_list::iterator kmp_stats_list::end() {
245     kmp_stats_list::iterator it;
246     it.ptr = this;
247     return it;
248 }
249 int kmp_stats_list::size() {
250     int retval;
251     kmp_stats_list::iterator it;
252     for(retval=0, it=begin(); it!=end(); it++, retval++) {}
253     return retval;
254 }
255 
256 /* ********************************************************************* */
257 /* ************* kmp_stats_list::iterator member functions ************* */
258 
259 kmp_stats_list::iterator::iterator() : ptr(NULL) {}
260 kmp_stats_list::iterator::~iterator() {}
261 kmp_stats_list::iterator kmp_stats_list::iterator::operator++() {
262     this->ptr = this->ptr->next;
263     return *this;
264 }
265 kmp_stats_list::iterator kmp_stats_list::iterator::operator++(int dummy) {
266     this->ptr = this->ptr->next;
267     return *this;
268 }
269 kmp_stats_list::iterator kmp_stats_list::iterator::operator--() {
270     this->ptr = this->ptr->prev;
271     return *this;
272 }
273 kmp_stats_list::iterator kmp_stats_list::iterator::operator--(int dummy) {
274     this->ptr = this->ptr->prev;
275     return *this;
276 }
277 bool kmp_stats_list::iterator::operator!=(const kmp_stats_list::iterator & rhs) {
278    return this->ptr!=rhs.ptr;
279 }
280 bool kmp_stats_list::iterator::operator==(const kmp_stats_list::iterator & rhs) {
281    return this->ptr==rhs.ptr;
282 }
283 kmp_stats_list* kmp_stats_list::iterator::operator*() const {
284     return this->ptr;
285 }
286 
287 /* *************************************************************** */
288 /* *************  kmp_stats_output_module functions ************** */
289 
290 const char* kmp_stats_output_module::outputFileName = NULL;
291 const char* kmp_stats_output_module::eventsFileName = NULL;
292 const char* kmp_stats_output_module::plotFileName   = NULL;
293 int kmp_stats_output_module::printPerThreadFlag       = 0;
294 int kmp_stats_output_module::printPerThreadEventsFlag = 0;
295 
296 // init() is called very near the beginning of execution time in the constructor of __kmp_stats_global_output
297 void kmp_stats_output_module::init()
298 {
299     char * statsFileName  = getenv("KMP_STATS_FILE");
300     eventsFileName        = getenv("KMP_STATS_EVENTS_FILE");
301     plotFileName          = getenv("KMP_STATS_PLOT_FILE");
302     char * threadStats    = getenv("KMP_STATS_THREADS");
303     char * threadEvents   = getenv("KMP_STATS_EVENTS");
304 
305     // set the stats output filenames based on environment variables and defaults
306     outputFileName = statsFileName;
307     eventsFileName = eventsFileName ? eventsFileName : "events.dat";
308     plotFileName   = plotFileName   ? plotFileName   : "events.plt";
309 
310     // set the flags based on environment variables matching: true, on, 1, .true. , .t. , yes
311     printPerThreadFlag        = __kmp_str_match_true(threadStats);
312     printPerThreadEventsFlag  = __kmp_str_match_true(threadEvents);
313 
314     if(printPerThreadEventsFlag) {
315         // assigns a color to each timer for printing
316         setupEventColors();
317     } else {
318         // will clear flag so that no event will be logged
319         timeStat::clearEventFlags();
320     }
321 
322     return;
323 }
324 
325 void kmp_stats_output_module::setupEventColors() {
326     int i;
327     int globalColorIndex = 0;
328     int numGlobalColors = sizeof(globalColorArray) / sizeof(rgb_color);
329     for(i=0;i<TIMER_LAST;i++) {
330         if(timeStat::logEvent((timer_e)i)) {
331             timerColorInfo[i] = globalColorArray[globalColorIndex];
332             globalColorIndex = (globalColorIndex+1)%numGlobalColors;
333         }
334     }
335     return;
336 }
337 
338 void kmp_stats_output_module::printTimerStats(FILE *statsOut, statistic const * theStats, statistic const * totalStats)
339 {
340     fprintf (statsOut, "Timer,                      SampleCount,    Min,      Mean,       Max,     Total,        SD\n");
341     for (timer_e s = timer_e(0); s<TIMER_LAST; s = timer_e(s+1)) {
342         statistic const * stat = &theStats[s];
343         char tag = timeStat::noUnits(s) ? ' ' : 'T';
344 
345         fprintf (statsOut, "%-28s, %s\n", timeStat::name(s), stat->format(tag, true).c_str());
346     }
347     // Also print the Total_ versions of times.
348     for (timer_e s = timer_e(0); s<TIMER_LAST; s = timer_e(s+1)) {
349         char tag = timeStat::noUnits(s) ? ' ' : 'T';
350         if (totalStats && !timeStat::noTotal(s))
351             fprintf(statsOut, "Total_%-22s, %s\n", timeStat::name(s), totalStats[s].format(tag, true).c_str());
352     }
353 }
354 
355 void kmp_stats_output_module::printCounterStats(FILE *statsOut, statistic const * theStats)
356 {
357     fprintf (statsOut, "Counter,                 ThreadCount,    Min,      Mean,       Max,     Total,        SD\n");
358     for (int s = 0; s<COUNTER_LAST; s++) {
359         statistic const * stat = &theStats[s];
360         fprintf (statsOut, "%-25s, %s\n", counter::name(counter_e(s)), stat->format(' ', true).c_str());
361     }
362 }
363 
364 void kmp_stats_output_module::printCounters(FILE * statsOut, counter const * theCounters)
365 {
366     // We print all the counters even if they are zero.
367     // That makes it easier to slice them into a spreadsheet if you need to.
368     fprintf (statsOut, "\nCounter,                    Count\n");
369     for (int c = 0; c<COUNTER_LAST; c++) {
370         counter const * stat = &theCounters[c];
371         fprintf (statsOut, "%-25s, %s\n", counter::name(counter_e(c)), formatSI(stat->getValue(), 9, ' ').c_str());
372     }
373 }
374 
375 void kmp_stats_output_module::printEvents(FILE* eventsOut, kmp_stats_event_vector* theEvents, int gtid) {
376     // sort by start time before printing
377     theEvents->sort();
378     for (int i = 0; i < theEvents->size(); i++) {
379         kmp_stats_event ev = theEvents->at(i);
380         rgb_color color = getEventColor(ev.getTimerName());
381         fprintf(eventsOut, "%d %lu %lu %1.1f rgb(%1.1f,%1.1f,%1.1f) %s\n",
382                 gtid,
383                 ev.getStart(),
384                 ev.getStop(),
385                 1.2 - (ev.getNestLevel() * 0.2),
386                 color.r, color.g, color.b,
387                 timeStat::name(ev.getTimerName())
388                );
389     }
390     return;
391 }
392 
393 void kmp_stats_output_module::windupExplicitTimers()
394 {
395     // Wind up any explicit timers. We assume that it's fair at this point to just walk all the explcit timers in all threads
396     // and say "it's over".
397     // If the timer wasn't running, this won't record anything anyway.
398     kmp_stats_list::iterator it;
399     for(it = __kmp_stats_list.begin(); it != __kmp_stats_list.end(); it++) {
400         for (int timer=0; timer<EXPLICIT_TIMER_LAST; timer++) {
401             (*it)->getExplicitTimer(explicit_timer_e(timer))->stop((timer_e)timer);
402         }
403     }
404 }
405 
406 void kmp_stats_output_module::printPloticusFile() {
407     int i;
408     int size = __kmp_stats_list.size();
409     FILE* plotOut = fopen(plotFileName, "w+");
410 
411     fprintf(plotOut, "#proc page\n"
412                      "   pagesize: 15 10\n"
413                      "   scale: 1.0\n\n");
414 
415     fprintf(plotOut, "#proc getdata\n"
416                      "   file: %s\n\n",
417                      eventsFileName);
418 
419     fprintf(plotOut, "#proc areadef\n"
420                      "   title: OpenMP Sampling Timeline\n"
421                      "   titledetails: align=center size=16\n"
422                      "   rectangle: 1 1 13 9\n"
423                      "   xautorange: datafield=2,3\n"
424                      "   yautorange: -1 %d\n\n",
425                      size);
426 
427     fprintf(plotOut, "#proc xaxis\n"
428                      "   stubs: inc\n"
429                      "   stubdetails: size=12\n"
430                      "   label: Time (ticks)\n"
431                      "   labeldetails: size=14\n\n");
432 
433     fprintf(plotOut, "#proc yaxis\n"
434                      "   stubs: inc 1\n"
435                      "   stubrange: 0 %d\n"
436                      "   stubdetails: size=12\n"
437                      "   label: Thread #\n"
438                      "   labeldetails: size=14\n\n",
439                      size-1);
440 
441     fprintf(plotOut, "#proc bars\n"
442                      "   exactcolorfield: 5\n"
443                      "   axis: x\n"
444                      "   locfield: 1\n"
445                      "   segmentfields: 2 3\n"
446                      "   barwidthfield: 4\n\n");
447 
448     // create legend entries corresponding to the timer color
449     for(i=0;i<TIMER_LAST;i++) {
450         if(timeStat::logEvent((timer_e)i)) {
451             rgb_color c = getEventColor((timer_e)i);
452             fprintf(plotOut, "#proc legendentry\n"
453                              "   sampletype: color\n"
454                              "   label: %s\n"
455                              "   details: rgb(%1.1f,%1.1f,%1.1f)\n\n",
456                              timeStat::name((timer_e)i),
457                              c.r, c.g, c.b);
458 
459         }
460     }
461 
462     fprintf(plotOut, "#proc legend\n"
463                      "   format: down\n"
464                      "   location: max max\n\n");
465     fclose(plotOut);
466     return;
467 }
468 
469 /*
470  * Print some useful information about
471  *    * the date and time this experiment ran.
472  *    * the machine on which it ran.
473  * We output all of this as stylised comments, though we may decide to parse some of it.
474  */
475 void kmp_stats_output_module::printHeaderInfo(FILE * statsOut)
476 {
477     std::time_t now = std::time(0);
478     char buffer[40];
479     char hostName[80];
480 
481     std::strftime(&buffer[0], sizeof(buffer), "%c", std::localtime(&now));
482     fprintf (statsOut, "# Time of run: %s\n", &buffer[0]);
483     if (gethostname(&hostName[0], sizeof(hostName)) == 0)
484         fprintf (statsOut,"# Hostname: %s\n", &hostName[0]);
485 #if KMP_ARCH_X86 || KMP_ARCH_X86_64
486     fprintf (statsOut, "# CPU:  %s\n", &__kmp_cpuinfo.name[0]);
487     fprintf (statsOut, "# Family: %d, Model: %d, Stepping: %d\n", __kmp_cpuinfo.family, __kmp_cpuinfo.model, __kmp_cpuinfo.stepping);
488     if (__kmp_cpuinfo.frequency == 0)
489         fprintf (statsOut, "# Nominal frequency: Unknown\n");
490     else
491         fprintf (statsOut, "# Nominal frequency: %sz\n", formatSI(double(__kmp_cpuinfo.frequency),9,'H').c_str());
492 #endif
493 }
494 
495 void kmp_stats_output_module::outputStats(const char* heading)
496 {
497     // Stop all the explicit timers in all threads
498     // Do this before declaring the local statistics because thay have constructors so will take time to create.
499     windupExplicitTimers();
500 
501     statistic allStats[TIMER_LAST];
502     statistic totalStats[TIMER_LAST];           /* Synthesized, cross threads versions of normal timer stats */
503     statistic allCounters[COUNTER_LAST];
504 
505     FILE * statsOut = outputFileName ? fopen (outputFileName, "a+") : stderr;
506     if (!statsOut)
507         statsOut = stderr;
508 
509     FILE * eventsOut;
510     if (eventPrintingEnabled()) {
511         eventsOut = fopen(eventsFileName, "w+");
512     }
513 
514     printHeaderInfo (statsOut);
515     fprintf(statsOut, "%s\n",heading);
516     // Accumulate across threads.
517     kmp_stats_list::iterator it;
518     for (it = __kmp_stats_list.begin(); it != __kmp_stats_list.end(); it++) {
519         int t = (*it)->getGtid();
520         // Output per thread stats if requested.
521         if (printPerThreadFlag) {
522             fprintf (statsOut, "Thread %d\n", t);
523             printTimerStats (statsOut, (*it)->getTimers(), 0);
524             printCounters   (statsOut, (*it)->getCounters());
525             fprintf (statsOut,"\n");
526         }
527         // Output per thread events if requested.
528         if (eventPrintingEnabled()) {
529             kmp_stats_event_vector events = (*it)->getEventVector();
530             printEvents(eventsOut, &events, t);
531         }
532 
533         // Accumulate timers.
534         for (timer_e s = timer_e(0); s<TIMER_LAST; s = timer_e(s+1)) {
535             // See if we should ignore this timer when aggregating
536             if ((timeStat::masterOnly(s) && (t != 0)) || // Timer is only valid on the master and this thread is a worker
537                 (timeStat::workerOnly(s) && (t == 0))    // Timer is only valid on a worker and this thread is the master
538                )
539             {
540                 continue;
541             }
542 
543             statistic * threadStat = (*it)->getTimer(s);
544             allStats[s] += *threadStat;
545 
546             // Add Total stats for timers that are valid in more than one thread
547             if (!timeStat::noTotal(s))
548                 totalStats[s].addSample(threadStat->getTotal());
549         }
550 
551         // Accumulate counters.
552         for (counter_e c = counter_e(0); c<COUNTER_LAST; c = counter_e(c+1)) {
553             if (counter::masterOnly(c) && t != 0)
554                 continue;
555             allCounters[c].addSample ((*it)->getCounter(c)->getValue());
556         }
557     }
558 
559     if (eventPrintingEnabled()) {
560         printPloticusFile();
561         fclose(eventsOut);
562     }
563 
564     fprintf (statsOut, "Aggregate for all threads\n");
565     printTimerStats (statsOut, &allStats[0], &totalStats[0]);
566     fprintf (statsOut, "\n");
567     printCounterStats (statsOut, &allCounters[0]);
568 
569     if (statsOut != stderr)
570         fclose(statsOut);
571 }
572 
573 /* ************************************************** */
574 /* *************  exported C functions ************** */
575 
576 // no name mangling for these functions, we want the c files to be able to get at these functions
577 extern "C" {
578 
579 void __kmp_reset_stats()
580 {
581     kmp_stats_list::iterator it;
582     for(it = __kmp_stats_list.begin(); it != __kmp_stats_list.end(); it++) {
583         timeStat * timers     = (*it)->getTimers();
584         counter * counters    = (*it)->getCounters();
585         explicitTimer * eTimers = (*it)->getExplicitTimers();
586 
587         for (int t = 0; t<TIMER_LAST; t++)
588             timers[t].reset();
589 
590         for (int c = 0; c<COUNTER_LAST; c++)
591             counters[c].reset();
592 
593         for (int t=0; t<EXPLICIT_TIMER_LAST; t++)
594             eTimers[t].reset();
595 
596         // reset the event vector so all previous events are "erased"
597         (*it)->resetEventVector();
598 
599         // May need to restart the explicit timers in thread zero?
600     }
601     KMP_START_EXPLICIT_TIMER(OMP_serial);
602     KMP_START_EXPLICIT_TIMER(OMP_start_end);
603 }
604 
605 // This function will reset all stats and stop all threads' explicit timers if they haven't been stopped already.
606 void __kmp_output_stats(const char * heading)
607 {
608     __kmp_stats_global_output.outputStats(heading);
609     __kmp_reset_stats();
610 }
611 
612 void __kmp_accumulate_stats_at_exit(void)
613 {
614     // Only do this once.
615     if (KMP_XCHG_FIXED32(&statsPrinted, 1) != 0)
616         return;
617 
618     __kmp_output_stats("Statistics on exit");
619 }
620 
621 void __kmp_stats_init(void)
622 {
623 }
624 
625 } // extern "C"
626 
627