Add communication region annotations

include/caliper/cali.h

@@ -390,6 +390,23 @@ cali_begin_phase(const char* name);
 void
 cali_end_phase(const char* name);
 
+/**
+ * \brief Begin communication region \a name
+ *
+ * A communication region can be used to mark communication operations (e.g.,
+ * MPI calls) that belong to a single communication pattern. They can be used
+ * to summarize communication pattern statistics. Otherwise they behave
+ * identical to regular Caliper regions.
+ */
+void
+cali_begin_comm_region(const char* name);
+
+/**
+ * \brief End phase region \a name
+ */
+void
+cali_end_comm_region(const char* name);
+
 /**
  * \brief Begin region where the value for \a attr is `true` on the blackboard.
  */

include/caliper/cali_macros.h

@@ -217,6 +217,17 @@ extern cali_id_t cali_annotation_attr_id;
 /// \brief Mark end of a phase region
 #define CALI_MARK_PHASE_END(name) \
     cali_end_phase(name)
+
+/// \brief Mark begin of a communication region
+///
+/// A communication region marks communication operations (e.g., MPI calls)
+/// that belong to a single communication pattern.
+#define CALI_MARK_COMM_REGION_BEGIN(name) \
+    cali_begin_comm_region(name)
+
+/// \brief Mark end of a communication region
+#define CALI_MARK_COMM_REGION_END(name) \
+    cali_end_comm_region(name)
 /**
  * \} (group)
  */

src/caliper/api.cpp

@@ -39,6 +39,7 @@ namespace cali
     Attribute region_attr;
     Attribute phase_attr;
     Attribute loop_attr;
+    Attribute comm_region_attr;
 
     void init_attribute_classes(Caliper* c) {
         class_aggregatable_attr =
@@ -65,6 +66,8 @@ namespace cali
             c->create_attribute("region", CALI_TYPE_STRING, CALI_ATTR_NESTED);
         phase_attr =
             c->create_attribute("phase", CALI_TYPE_STRING, CALI_ATTR_NESTED | CALI_ATTR_LEVEL_4);
+        comm_region_attr =
+            c->create_attribute("comm.region", CALI_TYPE_STRING, CALI_ATTR_NESTED | CALI_ATTR_LEVEL_1);
 
         cali_region_attr_id = region_attr.id();
         cali_phase_attr_id = phase_attr.id();

src/caliper/cali.cpp

@@ -32,6 +32,7 @@ namespace cali
 
 extern Attribute region_attr;
 extern Attribute phase_attr;
+extern Attribute comm_region_attr;
 
 }
 
@@ -404,6 +405,20 @@ cali_end_phase(const char* name)
     c.end_with_value_check(cali::phase_attr, Variant(name));
 }
 
+void
+cali_begin_comm_region(const char* name)
+{
+    Caliper c;
+    c.begin(cali::comm_region_attr, Variant(name));
+}
+
+void
+cali_end_comm_region(const char* name)
+{
+    Caliper c;
+    c.end_with_value_check(cali::comm_region_attr, Variant(name));
+}
+
 void
 cali_begin(cali_id_t attr_id)
 {

test/ci_app_tests/ci_test_mpi_before_cali.cpp

@@ -40,10 +40,10 @@ int main(int argc, char* argv[])
         MPI_Bcast(&val, 1, MPI_INT, 0, MPI_COMM_WORLD);
 
         int in  = val, out;
-
+        CALI_MARK_COMM_REGION_BEGIN("reduction");
         MPI_Reduce(&in, &out, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
-
         MPI_Barrier(MPI_COMM_WORLD);
+        CALI_MARK_COMM_REGION_END("reduction");
     }
 
     mgr.flush();