unit_tests: add threadpool unit test

tests/unit_tests/CMakeLists.txt

@@ -62,6 +62,7 @@ set(unit_tests_sources
   test_tx_utils.cpp
   test_peerlist.cpp
   test_protocol_pack.cpp
+  threadpool.cpp
   hardfork.cpp
   unbound.cpp
   uri.cpp

tests/unit_tests/threadpool.cpp

@@ -0,0 +1,101 @@
+// Copyright (c) 2018, The Monero Project
+// 
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+// 
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+// 
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+// 
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <atomic>
+#include "gtest/gtest.h"
+#include "misc_language.h"
+#include "common/threadpool.h"
+
+TEST(threadpool, wait_nothing)
+{
+  std::shared_ptr<tools::threadpool> tpool(tools::threadpool::getNewForUnitTests());
+  tools::threadpool::waiter waiter;
+  waiter.wait();
+}
+
+TEST(threadpool, wait_waits)
+{
+  std::shared_ptr<tools::threadpool> tpool(tools::threadpool::getNewForUnitTests());
+  tools::threadpool::waiter waiter;
+  std::atomic<bool> b(false);
+  tpool->submit(&waiter, [&b](){ epee::misc_utils::sleep_no_w(1000); b = true; });
+  ASSERT_FALSE(b);
+  waiter.wait();
+  ASSERT_TRUE(b);
+}
+
+TEST(threadpool, one_thread)
+{
+  std::shared_ptr<tools::threadpool> tpool(tools::threadpool::getNewForUnitTests(1));
+  tools::threadpool::waiter waiter;
+
+  std::atomic<unsigned int> counter(0);
+  for (size_t n = 0; n < 4096; ++n)
+  {
+    tpool->submit(&waiter, [&counter](){++counter;});
+  }
+  waiter.wait();
+  ASSERT_EQ(counter, 4096);
+}
+
+TEST(threadpool, many_threads)
+{
+  std::shared_ptr<tools::threadpool> tpool(tools::threadpool::getNewForUnitTests(256));
+  tools::threadpool::waiter waiter;
+
+  std::atomic<unsigned int> counter(0);
+  for (size_t n = 0; n < 4096; ++n)
+  {
+    tpool->submit(&waiter, [&counter](){++counter;});
+  }
+  waiter.wait();
+  ASSERT_EQ(counter, 4096);
+}
+
+static uint64_t fibonacci(std::shared_ptr<tools::threadpool> tpool, uint64_t n)
+{
+  if (n <= 1)
+    return n;
+  uint64_t f1, f2;
+  tools::threadpool::waiter waiter;
+  tpool->submit(&waiter, [&tpool, &f1, n](){ f1 = fibonacci(tpool, n-1); });
+  tpool->submit(&waiter, [&tpool, &f2, n](){ f2 = fibonacci(tpool, n-2); });
+  waiter.wait();
+  return f1 + f2;
+}
+
+TEST(threadpool, reentrency)
+{
+  std::shared_ptr<tools::threadpool> tpool(tools::threadpool::getNewForUnitTests(4));
+  tools::threadpool::waiter waiter;
+
+  uint64_t f = fibonacci(tpool, 13);
+  waiter.wait();
+  ASSERT_EQ(f, 233);
+}
+