Commit 92f9e5c7 authored by gbalduzz's avatar gbalduzz
Browse files

set affinity is a no-op on non-linux systems. 

Updated affinity_test.cpp.
parent bce2e7fc

include/dca/parallel/stdthread/thread_pool/affinity.hpp

+5 −1
Original line number Diff line number Diff line
@@ -19,11 +19,15 @@ namespace parallel { 
// dca::parallel::



// Returns a list of cores id for which the calling thread has affinity.

// If the macro __linux__ is not defined, returns an empty vector.

std::vector<int> get_affinity();



// Sets the affinity list of the current thread.

// If the macro __linux__ is not defined, performs a no-op.

void set_affinity(const std::vector<int>& cores);



// Number of cores used by this process.

// Returns the number of visible hardware cores.

// If the macro __linux__ is not defined, returns std::hardware_concurrency().

int get_core_count();



}  // namespace parallel

src/parallel/stdthread/thread_pool/affinity.cpp

+24 −5
Original line number Diff line number Diff line
@@ -9,24 +9,30 @@ 
//

// This file implements the methods in affinity.hpp.



// GNU extensions are required for linux-specific features for querying affinity

#if defined(__linux__) && !defined(_GNU_SOURCE)

#define _GNU_SOURCE

#endif



#include "dca/parallel/stdthread/thread_pool/affinity.hpp"



#include <iostream>

#include <cstdlib>

#include <stdexcept>

#include <thread>



// GNU extensions are required for linux-specific features for querying affinity

#ifndef _GNU_SOURCE

#define _GNU_SOURCE

#endif

#include "dca/util/ignore.hpp"



#if defined(__linux__)

#include <sched.h>

#include <stdexcept>

#endif



namespace dca {

namespace parallel {

// dca::parallel::



std::vector<int> get_affinity() {

#if defined(__linux__)

  cpu_set_t cpu_set_mask;



  auto status = sched_getaffinity(0, sizeof(cpu_set_t), &cpu_set_mask);
@@ -51,9 +57,14 @@ std::vector<int> get_affinity() { 
  }



  return cores;



#else  // !defined(__linux__)

  return {};

#endif

}



void set_affinity(const std::vector<int>& cores) {

#if defined(__linux__)

  cpu_set_t cpu_set_mask;

  CPU_ZERO(&cpu_set_mask);
@@ -62,12 +73,20 @@ void set_affinity(const std::vector<int>& cores) { 
  }



  sched_setaffinity(0, sizeof(cpu_set_t), &cpu_set_mask);

#else  // !defined(__linux__)

  dca::util::ignoreUnused(cores);

#endif

}



int get_core_count() {

#if defined(__linux__)

  cpu_set_t cpu_set_mask;

  sched_getaffinity(0, sizeof(cpu_set_t), &cpu_set_mask);

  return CPU_COUNT(&cpu_set_mask);



#else  // !defined(__linux__)

  return std::thread::hardware_concurrency();

#endif

}



}  // namespace parallel

test/unit/parallel/stdthread/thread_pool/affinity_test.cpp

+4 −5
Original line number Diff line number Diff line
@@ -13,7 +13,6 @@ 


#include <iostream>

#include <future>

#include <thread>



#include "gtest/gtest.h"
@@ -40,12 +39,12 @@ TEST(AffinityTest, All) { 
    dca::parallel::set_affinity(new_set);



    auto b = dca::parallel::get_affinity();

#if defined(__linux__)

    EXPECT_TRUE(equal(new_set, b));

#else

    EXPECT_TRUE(equal(std::vector<int>{}, b));

#endif

  });



  f.get();

}
 


 TEST(AffinityTest, Count) {

  EXPECT_EQ(std::thread::hardware_concurrency(), dca::parallel::get_core_count());

}