Adding utilities for perf profiling

benchmarks/Benchmark_wilson.cc

@@ -4,7 +4,7 @@
 
     Source file: ./benchmarks/Benchmark_wilson.cc
 
-    Copyright (C) 2015
+    Copyright (C) 2018
 
 Author: Peter Boyle <paboyle@ph.ed.ac.uk>
 Author: paboyle <paboyle@ph.ed.ac.uk>
@@ -32,6 +32,9 @@ using namespace std;
 using namespace Grid;
 using namespace Grid::QCD;
 
+
+#include "Grid/util/Profiling.h"
+
 template<class d>
 struct scal {
   d internal;
@@ -45,6 +48,7 @@ struct scal {
   };
 
 bool overlapComms = false;
+bool perfProfiling = false;
 
 int main (int argc, char ** argv)
 {
@@ -53,6 +57,9 @@ int main (int argc, char ** argv)
   if( GridCmdOptionExists(argv,argv+argc,"--asynch") ){
     overlapComms = true;
   }
+  if( GridCmdOptionExists(argv,argv+argc,"--perf") ){
+    perfProfiling = true;
+  }
 
   long unsigned int single_site_flops = 8*QCD::Nc*(7+16*QCD::Nc);
 
@@ -144,6 +151,21 @@ int main (int argc, char ** argv)
   double t1=usecond();
   double flops=single_site_flops*volume*ncall;
   
+  if (perfProfiling){
+  std::cout<<GridLogMessage << "Profiling Dw with perf"<<std::endl;
+    
+  System::profile("kernel", [&]() {
+    for(int i=0;i<ncall;i++){
+      Dw.Dhop(src,result,0);
+    }
+  });
+
+  std::cout<<GridLogMessage << "Generated kernel.data"<<std::endl;
+  std::cout<<GridLogMessage << "Use with: perf report -i kernel.data"<<std::endl;
+
+  }
+
+
   std::cout<<GridLogMessage << "Called Dw"<<std::endl;
   std::cout<<GridLogMessage << "flops per site " << single_site_flops << std::endl;
   std::cout<<GridLogMessage << "norm result "<< norm2(result)<<std::endl;

lib/util/Profiling.h

@@ -0,0 +1,72 @@
+   /*************************************************************************************
+
+    Grid physics library, www.github.com/paboyle/Grid 
+
+    Source file: ./lib/util/Profiling.h
+
+    Copyright (C) 2018
+
+    Author: Guido Cossu <guido.cossu@ed.ac.uk>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+    See the full license in the file "LICENSE" in the top level distribution directory
+    *************************************************************************************/
+    /*  END LEGAL */
+
+#ifndef GRID_PERF_PROFILING_H
+#define GRID_PERF_PROFILING_H
+
+#include <sstream>
+#include <iostream>
+#include <functional>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <signal.h>
+
+struct System
+{
+    static void profile(const std::string& name,std::function<void()> body) {
+        std::string filename = name.find(".data") == std::string::npos ? (name + ".data") : name;
+
+        // Launch profiler
+        pid_t pid;
+        std::stringstream s;
+        s << getpid();
+        pid = fork();
+        if (pid == 0) {
+            auto fd=open("/dev/null",O_RDWR);
+            dup2(fd,1);
+            dup2(fd,2);
+            exit(execl("/usr/bin/perf","perf","record","-o",filename.c_str(),"-p",s.str().c_str(),nullptr));
+        }
+
+        // Run body
+        body();
+
+        // Kill profiler  
+        kill(pid,SIGINT);
+        waitpid(pid,nullptr,0);
+    }
+
+    static void profile(std::function<void()> body) {
+        profile("perf.data",body);
+    }
+};
+
+#endif // GRID_PERF_PROFILING_H