Source/bmalloc/libpas/src/test/ScavengerExternalWorkTests.cpp

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#include "TestHarness.h"

#include <atomic>
#include <chrono>
#include <thread>

#include "pas_scavenger.h"

using namespace std;

extern "C" inline bool incrementCounter(void* counter)
{
    auto* atomic_counter = reinterpret_cast<std::atomic<int>*>(counter);
    (*atomic_counter)++;
    return false;
}

inline void testCallbacksAreCalledWhenExpected(int scavenger_on_ms, int scavenger_off_ms)
{
    TestScope frequentScavenging(
        "frequent-scavenging",
        [] () {
            pas_scavenger_period_in_milliseconds = 1.;
            pas_scavenger_max_epoch_delta = -1ll * 1000ll * 1000ll;
        });

    auto counter = 0;
    [[maybe_unused]] void* counter_ptr = reinterpret_cast<void*>(&counter);
    CHECK(pas_scavenger_try_install_foreign_work_callback(incrementCounter, 1, counter_ptr));

    int prevCounterValue;
    {
        SuspendScavengerScope suspendScavenger;
        prevCounterValue = counter;

        std::this_thread::sleep_for(std::chrono::milliseconds(scavenger_off_ms));
        CHECK_EQUAL(counter, prevCounterValue);
    }

    std::this_thread::sleep_for(std::chrono::milliseconds(scavenger_on_ms));
    CHECK_GREATER(counter, prevCounterValue);
}

void addScavengerExternalWorkTests()
{
    ADD_TEST(testCallbacksAreCalledWhenExpected(50, 50));
}