Expose more parallelism with relaxed atomics (suggested in #9938). Fix a test to check the exclusive or of two properties rather than just or.

src/test/checkqueue_tests.cpp

@@ -38,7 +38,7 @@ struct FakeCheckCheckCompletion {
     static std::atomic<size_t> n_calls;
     bool operator()()
     {
-        ++n_calls;
+        n_calls.fetch_add(1, std::memory_order_relaxed);
         return true;
     }
     void swap(FakeCheckCheckCompletion& x){};
@@ -88,15 +88,15 @@ struct MemoryCheck {
         //
         // Really, copy constructor should be deletable, but CCheckQueue breaks
         // if it is deleted because of internal push_back.
-        fake_allocated_memory += b;
+        fake_allocated_memory.fetch_add(b, std::memory_order_relaxed);
     };
     MemoryCheck(bool b_) : b(b_)
     {
-        fake_allocated_memory += b;
+        fake_allocated_memory.fetch_add(b, std::memory_order_relaxed);
     };
-    ~MemoryCheck(){
-        fake_allocated_memory -= b;
-    
+    ~MemoryCheck()
+    {
+        fake_allocated_memory.fetch_sub(b, std::memory_order_relaxed);
     };
     void swap(MemoryCheck& x) { std::swap(b, x.b); };
 };
@@ -117,9 +117,9 @@ struct FrozenCleanupCheck {
     {
         if (should_freeze) {
             std::unique_lock<std::mutex> l(m);
-            nFrozen = 1;
+            nFrozen.store(1, std::memory_order_relaxed);
             cv.notify_one();
-            cv.wait(l, []{ return nFrozen == 0;});
+            cv.wait(l, []{ return nFrozen.load(std::memory_order_relaxed) == 0;});
         }
     }
     void swap(FrozenCleanupCheck& x){std::swap(should_freeze, x.should_freeze);};
@@ -262,7 +262,7 @@ BOOST_AUTO_TEST_CASE(test_CheckQueue_Recovers_From_Failure)
                 control.Add(vChecks);
             }
             bool r =control.Wait();
-            BOOST_REQUIRE(r || end_fails);
+            BOOST_REQUIRE(r != end_fails);
         }
     }
     tg.interrupt_all();
@@ -361,11 +361,14 @@ BOOST_AUTO_TEST_CASE(test_CheckQueue_FrozenCleanup)
         std::unique_lock<std::mutex> l(FrozenCleanupCheck::m);
         // Wait until the queue has finished all jobs and frozen
         FrozenCleanupCheck::cv.wait(l, [](){return FrozenCleanupCheck::nFrozen == 1;});
-        // Try to get control of the queue a bunch of times
-        for (auto x = 0; x < 100 && !fails; ++x) {
-            fails = queue->ControlMutex.try_lock();
-        }
-        // Unfreeze
+    }
+    // Try to get control of the queue a bunch of times
+    for (auto x = 0; x < 100 && !fails; ++x) {
+        fails = queue->ControlMutex.try_lock();
+    }
+    {
+        // Unfreeze (we need lock n case of spurious wakeup)
+        std::unique_lock<std::mutex> l(FrozenCleanupCheck::m);
         FrozenCleanupCheck::nFrozen = 0;
     }
     // Awaken frozen destructor