LUMIERA.clone/tests/library/sync-classlock-test.cpp
Ichthyostega a20e233ca0 Library: now using controlled seed and replaced rand (closes #1378)
After augmenting our `lib/random.hpp` abstraction framework to add the necessary flexibility,
a common seeding scheme was ''built into the Test-Runner.''
 * all tests relying on some kind of randomness should invoke `seedRand()`
 * this draws a seed from the `entropyGen` — which is also documented in the log
 * individual tests can now be launched with `--seed` to force a dedicated seed
 * moreover, tests should build a coherent structure of linked generators,
   especially when running concurrently. The existing tests were adapted accordingly

All usages of `rand()` in the code base were investigated and replaced
by suitable calls to our abstraction framework; the code base is thus
isolated from the actual implementation, simplifying further adaptation.
2024-11-17 19:45:41 +01:00

109 lines
4.1 KiB
C++

/*
SyncClasslock(Test) - validate the type-based Monitor locking
Copyright (C) Lumiera.org
2008, Hermann Vosseler <Ichthyostega@web.de>
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., 675 Mass Ave, Cambridge, MA 02139, USA.
* *****************************************************/
/** @file sync-classlock-test.cpp
** unit test \ref SyncClasslock_test
*/
#include "lib/test/run.hpp"
#include "lib/sync-classlock.hpp"
#include "lib/scoped-collection.hpp"
#include "lib/thread.hpp"
using test::Test;
//using vault::ThreadJoinable; //////////////////WIP
namespace lib {
namespace test {
namespace { // Parameters for multithreaded contention test
const uint NUM_THREADS = 20; ///< number of contending threads to create
const uint NUM_LOOP = 1000; ///< number of loop iterations per thread
}
/**********************************************************************//**
* @test check proper handling of class (not instance)-based Monitor locks.
* Because no instance is available in this case, a hidden storage for the
* Monitor object needs to be provided in a way safe for use even in the
* static startup/shutdown phase. This can not directly validate this
* allocation of a shared monitor object behind the scenes, but it
* can verify the monitor is indeed shared by all ClassLock instances
* templated to a specific type.
*
* @see sync.hpp
*/
class SyncClasslock_test : public Test
{
virtual void
run (Arg)
{
seedRand();
auto gen = buildCappedSubSequence(defaultGen);
int contended = 0;
using Threads = lib::ScopedCollection<ThreadJoinable<>>;
// Start a bunch of threads with random access pattern
Threads threads{NUM_THREADS,
[&](Threads::ElementHolder& storage)
{
storage.create<ThreadJoinable<>> ("Sync-ClassLock stress test"
,[&]{
for (uint i=0; i<NUM_LOOP; ++i)
{
uint delay = gen.i(10);
usleep (delay);
{
ClassLock<void> guard;
++contended;
}
}
});
}
};
for (auto& thread : threads)
thread.join(); // block until thread terminates // @suppress("Return value not evaluated")
CHECK (contended == NUM_THREADS * NUM_LOOP,
"ALARM: Lock failed, concurrent modification "
"during counter increment. Delta == %d"
,NUM_THREADS * NUM_LOOP - contended);
}
};
/** Register this test class... */
LAUNCHER (SyncClasslock_test, "unit common");
}} // namespace lib::test