Let dist interface control logging output (#2930)

src/ngraph/distributed.hpp

@@ -31,6 +31,7 @@ namespace ngraph
         virtual const std::string& get_name() const = 0;
         virtual int get_size() = 0;
         virtual int get_rank() = 0;
+        virtual void log_print(const std::string& timestamp, const std::vector<char>& buf) = 0;
 
         virtual void
             all_reduce(void* in, void* out, element::Type_t element_type, size_t count) = 0;

src/ngraph/distributed/mlsl.hpp

@@ -60,6 +60,11 @@ namespace ngraph
                 return static_cast<int>(MLSL::Environment::GetEnv().GetProcessIdx());
             }
 
+            void log_print(const std::string& timestamp, const std::vector<char>& buf) override
+            {
+                std::printf("%s [MLSL RANK: %d]: %s\n", timestamp.c_str(), get_rank(), buf.data());
+            }
+
             void
                 all_reduce(void* in, void* out, element::Type_t element_type, size_t count) override
             {

src/ngraph/distributed/null.hpp

@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <cstdio>
 #include <string>
 
 #include "ngraph/distributed.hpp"
@@ -30,6 +31,10 @@ namespace ngraph
             const std::string& get_name() const override { return m_name; }
             int get_size() override { return 0; }
             int get_rank() override { return 0; }
+            void log_print(const std::string& timestamp, const std::vector<char>& buf) override
+            {
+                std::printf("%s: %s\n", timestamp.c_str(), buf.data());
+            }
             void
                 all_reduce(void* in, void* out, element::Type_t element_type, size_t count) override
             {

src/ngraph/distributed/open_mpi.hpp

@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <cstdio>
 #include <iostream>
 
 #include "ngraph/distributed.hpp"
@@ -70,6 +71,12 @@ namespace ngraph
                 return rank;
             }
 
+            void log_print(const std::string& timestamp, const std::vector<char>& buf) override
+            {
+                std::printf(
+                    "%s [OpenMPI RANK: %d]: %s\n", timestamp.c_str(), get_rank(), buf.data());
+            }
+
             void
                 all_reduce(void* in, void* out, element::Type_t element_type, size_t count) override
             {

src/ngraph/log.cpp

@@ -112,11 +112,7 @@ void ngraph::LogPrintf(const char* fmt, ...)
     std::vsnprintf(buf.data(), buf.size(), fmt, args2);
 #pragma GCC diagnostic pop
     va_end(args2);
-
-    std::printf("%s [RANK: %d]: %s\n",
-                get_timestamp().c_str(),
-                get_distributed_interface()->get_rank(),
-                buf.data());
+    get_distributed_interface()->log_print(get_timestamp(), buf);
 }
 
 // This function will be executed only once during startup (loading of the DSO)