[STATS] Adding process id to output filename

[tlwilmar]

Summary

This change appends the process id to the KMP_STATS_FILE (if specified) which enables MPI processes to output their stats to separate files.

Patch by Johnny Peyton.

[AndreyChurbanov]

LGTM

runtime/src/kmp_stats.h

  public:
     struct rgb_color {
         float r;
         float g;
         float b;
     };
 
  private:
-    static const char* outputFileName;
+    std::string outputFileName;
     static const char* eventsFileName;
     static const char* plotFileName;
     static int printPerThreadFlag;
     static int printPerThreadEventsFlag;
     static const rgb_color globalColorArray[];
     static       rgb_color timerColorInfo[];
 
     void init();

runtime/src/kmp_stats.cpp

 }
 kmp_stats_list* kmp_stats_list::iterator::operator*() const {
     return this->ptr;
 }
 
 /* *************************************************************** */
 /* *************  kmp_stats_output_module functions ************** */
 
-const char* kmp_stats_output_module::outputFileName = NULL;
 const char* kmp_stats_output_module::eventsFileName = NULL;
 const char* kmp_stats_output_module::plotFileName   = NULL;
 int kmp_stats_output_module::printPerThreadFlag       = 0;
 int kmp_stats_output_module::printPerThreadEventsFlag = 0;
 
 // init() is called very near the beginning of execution time in the constructor of __kmp_stats_global_output
 void kmp_stats_output_module::init()
 {
     char * statsFileName  = getenv("KMP_STATS_FILE");
     eventsFileName        = getenv("KMP_STATS_EVENTS_FILE");
     plotFileName          = getenv("KMP_STATS_PLOT_FILE");
     char * threadStats    = getenv("KMP_STATS_THREADS");
     char * threadEvents   = getenv("KMP_STATS_EVENTS");
 
     // set the stats output filenames based on environment variables and defaults
-    outputFileName = statsFileName;
+    if(statsFileName) {
+        // append the process id to the output filename
+        // events.csv --> events-pid.csv
+        size_t index;
+        std::string baseFileName, pid, suffix;
+        std::stringstream ss;
+        outputFileName = std::string(statsFileName);
+        index = outputFileName.find_last_of('.');
+        if(index == std::string::npos) {
+            baseFileName = outputFileName;
+        } else {
+            baseFileName = outputFileName.substr(0, index);
+            suffix = outputFileName.substr(index);
+        }
+        ss << getpid();
+        pid = ss.str();
+        outputFileName = baseFileName + "-" + pid + suffix;
+    }
     eventsFileName = eventsFileName ? eventsFileName : "events.dat";
     plotFileName   = plotFileName   ? plotFileName   : "events.plt";
 
     // set the flags based on environment variables matching: true, on, 1, .true. , .t. , yes
     printPerThreadFlag        = __kmp_str_match_true(threadStats);
     printPerThreadEventsFlag  = __kmp_str_match_true(threadEvents);
 
     if(printPerThreadEventsFlag) {
void kmp_stats_output_module::outputStats(const char* heading)
     // Stop all the explicit timers in all threads
     // Do this before declaring the local statistics because thay have constructors so will take time to create.
     windupExplicitTimers();
 
     statistic allStats[TIMER_LAST];
     statistic totalStats[TIMER_LAST];           /* Synthesized, cross threads versions of normal timer stats */
     statistic allCounters[COUNTER_LAST];
 
-    FILE * statsOut = outputFileName ? fopen (outputFileName, "a+") : stderr;
+    FILE * statsOut = !outputFileName.empty() ? fopen (outputFileName.c_str(), "a+") : stderr;
     if (!statsOut)
         statsOut = stderr;
 
     FILE * eventsOut;
     if (eventPrintingEnabled()) {
         eventsOut = fopen(eventsFileName, "w+");
     }