#2302: Refine access to PAPI events and use preset events

src/vt/context/runnable_context/lb_data.cc

@@ -51,7 +51,9 @@ void LBData::start(TimeType time) {
   if (should_instrument_) {
     lb_data_->start(time);
   }
+}
 
+void LBData::startPAPIMetrics() {
   /* -- PAPI START -- */
   /* Start counting events in the Event Set */
   papi_retval_ = PAPI_start(EventSet_);
@@ -71,7 +73,9 @@ void LBData::finish(TimeType time) {
   if (should_instrument_) {
     lb_data_->stop(time);
   }
+}
 
+void LBData::stopPAPIMetrics() {
   /* -- PAPI STOP -- */
   /* Stop the counting of events in the Event Set */
   papi_retval_ = PAPI_stop(EventSet_, papi_values_);
@@ -104,11 +108,22 @@ typename LBData::ElementIDStruct const& LBData::getCurrentElementID() const {
   return cur_elm_id_;
 }
 
-std::unordered_map<std::string, double> LBData::getPAPIMetrics() const {
+std::unordered_map<std::string, double> LBData::getPAPIMetrics() {
   std::unordered_map<std::string, double> papi_metrics = {};
-  for (size_t i = 0; i < native_events_.size(); i++) {
-    papi_metrics[native_events_[i]] = papi_values_[i];
+  char event_code_str[PAPI_MAX_STR_LEN];
+  for (size_t i = 0; i < events_.size(); i++) {
+    papi_retval_ = PAPI_event_code_to_name(events_[i], event_code_str);
+    if (papi_retval_ != PAPI_OK)
+      handle_papi_error(papi_retval_, "LBData getPAPIMetrics: couldn't get name from event code: ");
+    papi_metrics[std::string(event_code_str)] = papi_values_[i];
   }
+  papi_metrics[std::string("real_time")] = end_real_usec_ - start_real_usec_;
+  papi_metrics[std::string("real_cycles")] = end_real_cycles_ - start_real_cycles_;
+  papi_metrics[std::string("virt_time")] = end_virt_usec_ - start_virt_usec_;
+  papi_metrics[std::string("virt_cycles")] = end_virt_cycles_ - start_virt_cycles_;
+  // for (auto [name, value] : papi_metrics) {
+  //   fmt::print("{}: {}\n", name, value);
+  // }
   return papi_metrics;
 }
 

src/vt/context/runnable_context/lb_data.h

@@ -60,7 +60,7 @@ struct LBData {
   using ElementIDStruct = elm::ElementIDStruct;
   using ElementLBData    = elm::ElementLBData;
 
-  void handle_papi_error (int retval, std::string info)
+  void handle_papi_error (int retval, std::string info) const
   {
     printf("%s: PAPI error %d: %s\n", info.c_str(), retval, PAPI_strerror(retval));
     exit(1);
@@ -95,16 +95,12 @@ struct LBData {
       exit(1);
     }
 
-    for (const auto& event_name : native_events_) {
-      int native = 0x0;
-      papi_retval_ = PAPI_event_name_to_code(event_name.c_str(), &native);
+    for (const auto& event : events_) {
+      papi_retval_ = PAPI_add_event(EventSet_, event);
+      char event_code_str[PAPI_MAX_STR_LEN];
       if (papi_retval_ != PAPI_OK) {
-        printf("LBData Constructor 2: Couldn't event_name_to_code for %s: PAPI error %d: %s\n",event_name.c_str(), papi_retval_, PAPI_strerror(papi_retval_));
-        exit(1);
-      }
-      papi_retval_ = PAPI_add_event(EventSet_, native);
-      if (papi_retval_ != PAPI_OK) {
-        printf("LBData Constructor 2: Couldn't add %s to the PAPI Event Set: PAPI error %d: %s\n",event_name.c_str(), papi_retval_, PAPI_strerror(papi_retval_));
+        PAPI_event_code_to_name(event, event_code_str);
+        printf("LBData Constructor 2: Couldn't add %s: PAPI error %d: %s\n", event_code_str, papi_retval_, PAPI_strerror(papi_retval_));
         exit(1);
       }
     }
@@ -144,12 +140,25 @@ struct LBData {
    */
   ElementIDStruct const& getCurrentElementID() const;
 
+  /**
+   * \brief Start PAPI metrics map for the running context
+   */
+  void startPAPIMetrics();
+
+  /**
+   * \brief Stop PAPI metrics map for the running context
+   * 
+   * \note has to be called after startPAPIMetrics
+   * 
+   */
+  void stopPAPIMetrics();
+
   /**
    * \brief Get the current PAPI metrics map for the running context
    *
    * \return the PAPI metrics map
    */
-  std::unordered_map<std::string, double> getPAPIMetrics() const;
+  std::unordered_map<std::string, double> getPAPIMetrics();
 
 private:
   ElementLBData* lb_data_ = nullptr;     /**< Element LB data */
@@ -159,8 +168,8 @@ struct LBData {
   int papi_retval_;
   long long start_real_cycles_, end_real_cycles_, start_real_usec_, end_real_usec_;
   long long start_virt_cycles_, end_virt_cycles_, start_virt_usec_, end_virt_usec_;
-  std::vector<std::string> native_events_ = {"instructions", "cache-misses", "fp_arith_inst_retired.scalar_double"};
-  long_long papi_values_[3];
+  std::vector<int> events_ = {PAPI_L1_DCM, PAPI_TOT_INS};
+  long_long papi_values_[5];
 };
 
 }} /* end namespace vt::ctx */

src/vt/context/runnable_context/lb_data.impl.h

@@ -70,16 +70,12 @@ LBData::LBData(ElmT* in_elm, MsgT* msg)
     exit(1);
   }
 
-  for (const auto& event_name : native_events_) {
-    int native = 0x0;
-    papi_retval_ = PAPI_event_name_to_code(event_name.c_str(), &native);
+  for (const auto& event : events_) {
+    papi_retval_ = PAPI_add_event(EventSet_, event);
+    char event_code_str[PAPI_MAX_STR_LEN];
     if (papi_retval_ != PAPI_OK) {
-      printf("LBData Constructor 1: Couldn't event_name_to_code for %s: PAPI error %d: %s\n",event_name.c_str(), papi_retval_, PAPI_strerror(papi_retval_));
-      exit(1);
-    }
-    papi_retval_ = PAPI_add_event(EventSet_, native);
-    if (papi_retval_ != PAPI_OK) {
-      printf("LBData Constructor 1: Couldn't add %s to the PAPI Event Set: PAPI error %d: %s\n",event_name.c_str(), papi_retval_, PAPI_strerror(papi_retval_));
+      PAPI_event_code_to_name(event, event_code_str);
+      printf("LBData Constructor 1: Couldn't add %s: PAPI error %d: %s\n", event_code_str, papi_retval_, PAPI_strerror(papi_retval_));
       exit(1);
     }
   }

src/vt/runnable/runnable.cc

@@ -199,7 +199,7 @@ void RunnableNew::run() {
 #endif
 }
 
-std::unordered_map<std::string, double> RunnableNew::getPAPIMetrics() const {
+std::unordered_map<std::string, double> RunnableNew::getPAPIMetrics() {
   std::unordered_map<std::string, double> result = {};
   if (contexts_.has_lb)
   {

src/vt/runnable/runnable.h

@@ -321,12 +321,25 @@ struct RunnableNew {
    */
   BaseMsgType* getMsg() const { return msg_.get(); }
 
+  /**
+   * \brief Start PAPI metrics map for the running context
+   */
+  void startPAPIMetrics() { contexts_.lb.startPAPIMetrics(); }
+
+  /**
+   * \brief Stop PAPI metrics map for the running context
+   * 
+   * \note has to be called after startPAPIMetrics
+   * 
+   */
+  void stopPAPIMetrics() { contexts_.lb.stopPAPIMetrics(); }
+
   /**
    * \brief Get the dictionnary of PAPI metrics associated with the runnable
    *
    * \return the dictionnary
    */
-  std::unordered_map<std::string, double> getPAPIMetrics() const;
+  std::unordered_map<std::string, double> getPAPIMetrics();
 
 #if vt_check_enabled(fcontext)
   /**