From 837a83fc16b601d4abc68aa859e58c9abdf04430 Mon Sep 17 00:00:00 2001
From: tqiu <tqiu@bda-04.domain_not_set.invalid>
Date: Tue, 26 Jan 2021 17:32:18 +0100
Subject: [PATCH] Added error checking and std::call_once

---
 opm/simulators/linalg/bda/fgpilu.cpp | 13 +++++++++----
 opm/simulators/linalg/bda/fgpilu.hpp |  6 +++---
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/opm/simulators/linalg/bda/fgpilu.cpp b/opm/simulators/linalg/bda/fgpilu.cpp
index 70226f44f..d57ca981a 100644
--- a/opm/simulators/linalg/bda/fgpilu.cpp
+++ b/opm/simulators/linalg/bda/fgpilu.cpp
@@ -487,9 +487,13 @@ void FGPILU::decomposition(
     const int block_size = 3;
 
     try {
-        if (initialized == false) {
+        // just put everything in the capture list
+        std::call_once(initialize_flag, [&](){
             cl::Program::Sources source(1, std::make_pair(fgpilu_sweep_s, strlen(fgpilu_sweep_s)));  // what does this '1' mean? cl::Program::Sources is of type 'std::vector<std::pair<const char*, long unsigned int> >'
             cl::Program program = cl::Program(*context, source, &err);
+            if (err != CL_SUCCESS) {
+                OPM_THROW(std::logic_error, "FGPILU OpenCL could not create Program");
+            }
 
             std::vector<cl::Device> devices = context->getInfo<CL_CONTEXT_DEVICES>();
             program.build(devices);
@@ -499,6 +503,9 @@ void FGPILU::decomposition(
                                                      cl::Buffer&, cl::Buffer&, cl::Buffer&,
                                                      cl::Buffer&, cl::Buffer&,
                                                      const int, cl::LocalSpaceArg, cl::LocalSpaceArg>(cl::Kernel(program, "fgpilu_sweep", &err)));
+            if (err != CL_SUCCESS) {
+                OPM_THROW(std::logic_error, "FGPILU OpenCL could not create Kernel");
+            }
 
             // allocate GPU memory
             d_Ut_vals = cl::Buffer(*context, CL_MEM_READ_WRITE, sizeof(double) * Ut_nnzbs * block_size * block_size);
@@ -530,9 +537,7 @@ void FGPILU::decomposition(
                 out << "FGPILU PARALLEL: " << PARALLEL;
                 OpmLog::info(out.str());
             }
-
-            initialized = true;
-        }
+        });
 
 
         // copy to GPU
diff --git a/opm/simulators/linalg/bda/fgpilu.hpp b/opm/simulators/linalg/bda/fgpilu.hpp
index d51c21061..880db43b2 100644
--- a/opm/simulators/linalg/bda/fgpilu.hpp
+++ b/opm/simulators/linalg/bda/fgpilu.hpp
@@ -21,8 +21,9 @@
 #define FGPILU_HEADER_INCLUDED
 
 
-#include <opm/simulators/linalg/bda/opencl.hpp>
+#include <mutex>
 
+#include <opm/simulators/linalg/bda/opencl.hpp>
 
 
 namespace bda
@@ -43,6 +44,7 @@ namespace bda
 
         cl::Event event;
         cl_int err;
+        std::once_flag initialize_flag;
 
         std::unique_ptr<cl::make_kernel<cl::Buffer&, cl::Buffer&, cl::Buffer&,
                                         cl::Buffer&, cl::Buffer&, cl::Buffer&,
@@ -50,8 +52,6 @@ namespace bda
                                         cl::Buffer&, cl::Buffer&,
                                         const int, cl::LocalSpaceArg, cl::LocalSpaceArg> > fgpilu_sweep_k;
 
-        bool initialized = false;
-
     public:
         /// Executes the FGPILU sweeps
         /// also copies data from CPU to GPU and GPU to CPU