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#include "lf_stack.h"
#include "ut_common.h"
#include <library/cpp/testing/unittest/registar.h>
#include <util/generic/vector.h>
namespace NKikimr {
Y_UNIT_TEST_SUITE(TLockFreeIntrusiveStackTest) {
template<template<class> class TItemBase, template<class> class TStack>
void DoConcurrent(const size_t itemsCount, const size_t workersCount) {
static constexpr size_t Iterations = 100000;
struct TMyItem : public TItemBase<TMyItem> {
size_t Count = 0; // this count is not lock-free
};
TVector<TMyItem> rawItems(itemsCount);
TStack<TMyItem> stack;
for (auto& item : rawItems) {
stack.Push(&item);
}
std::atomic<size_t> totalCount{ 0 };
TVector<THolder<TWorkerThread>> workers(workersCount);
for (size_t i = 0; i < workersCount; ++i) {
workers[i] = TWorkerThread::Spawn([&]() {
THPTimer timer;
while (timer.Passed() < 5.0) {
size_t added = 0;
for (size_t i = 0; i < Iterations; ++i) {
if (TMyItem* item = stack.Pop()) {
item->Count++;
stack.Push(item);
++added;
} else {
Y_VERIFY(itemsCount < workersCount, "Unexpected nullptr from stack.Pop()");
}
}
totalCount.fetch_add(added, std::memory_order_relaxed);
}
});
}
for (size_t i = 0; i < workersCount; ++i) {
workers[i]->Join();
}
size_t checkCount = 0;
for (auto& item : rawItems) {
checkCount += item.Count;
}
UNIT_ASSERT_VALUES_EQUAL(checkCount, totalCount.load());
}
Y_UNIT_TEST(ConcurrentRefCountNeverEmpty) {
DoConcurrent<TLockFreeIntrusiveStackItemWithRefCount, TLockFreeIntrusiveStackWithRefCount>(4, 4);
}
Y_UNIT_TEST(ConcurrentRefCountHeavyContention) {
DoConcurrent<TLockFreeIntrusiveStackItemWithRefCount, TLockFreeIntrusiveStackWithRefCount>(4, 8);
}
#if 0
// Currently causes link errors with arcadia clang
Y_UNIT_TEST(ConcurrentDCASNeverEmpty) {
DoConcurrent<TLockFreeIntrusiveStackItemWithDCAS, TLockFreeIntrusiveStackWithDCAS>(4, 4);
}
// Currently causes link errors with arcadia clang
Y_UNIT_TEST(ConcurrentDCASHeavyContention) {
DoConcurrent<TLockFreeIntrusiveStackItemWithDCAS, TLockFreeIntrusiveStackWithDCAS>(4, 8);
}
#endif
Y_UNIT_TEST(ConcurrentAutoNeverEmpty) {
DoConcurrent<TLockFreeIntrusiveStackItem, TLockFreeIntrusiveStack>(4, 4);
}
Y_UNIT_TEST(ConcurrentAutoHeavyContention) {
DoConcurrent<TLockFreeIntrusiveStackItem, TLockFreeIntrusiveStack>(4, 8);
}
}
}
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