1 files changed, 149 insertions, 0 deletions
diff --git a/src/test/common/test_intrusive_lru.cc b/src/test/common/test_intrusive_lru.cc
new file mode 100644
index 000000000..f242bdba1
--- /dev/null
+++ b/src/test/common/test_intrusive_lru.cc
@@ -0,0 +1,149 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include <stdio.h>
+#include "gtest/gtest.h"
+#include "common/intrusive_lru.h"
+
+template <typename TestLRUItem>
+struct item_to_unsigned {
+  using type = unsigned;
+  const type &operator()(const TestLRUItem &item) {
+    return item.key;
+  }
+};
+
+struct TestLRUItem : public ceph::common::intrusive_lru_base<
+  ceph::common::intrusive_lru_config<
+    unsigned, TestLRUItem, item_to_unsigned<TestLRUItem>>> {
+  unsigned key = 0;
+  int value = 0;
+  bool seen = false;
+
+  TestLRUItem(unsigned key) : key(key) {}
+};
+
+class LRUTest : public TestLRUItem::lru_t {
+public:
+  auto add(unsigned int key, int value) {
+    auto [ref, key_existed] = get_or_create(key);
+    if (!key_existed) {
+      ref->value = value;
+    }
+    return std::pair(ref, key_existed);
+  }
+};
+
+TEST(LRU, add_immediate_evict) {
+  LRUTest cache;
+  unsigned int key = 1;
+  int value1 = 2;
+  int value2 = 3;
+  {
+    auto [ref, existed] = cache.add(key, value1);
+    ASSERT_TRUE(ref);
+    ASSERT_EQ(value1, ref->value);
+    ASSERT_FALSE(existed);
+  }
+  {
+    auto [ref2, existed] = cache.add(key, value2);
+    ASSERT_EQ(value2, ref2->value);
+    ASSERT_FALSE(existed);
+  }
+}
+
+TEST(LRU, lookup_lru_size) {
+  LRUTest cache;
+  int key = 1;
+  int value = 1;
+  cache.set_target_size(1);
+  {
+    auto [ref, existed] = cache.add(key, value);
+    ASSERT_TRUE(ref);
+    ASSERT_FALSE(existed);
+  }
+  {
+    auto [ref, existed] = cache.add(key, value);
+    ASSERT_TRUE(ref);
+    ASSERT_TRUE(existed);
+  }
+  cache.set_target_size(0);
+  auto [ref2, existed2] = cache.add(key, value);
+  ASSERT_TRUE(ref2);
+  ASSERT_FALSE(existed2);
+  {
+    auto [ref, existed] = cache.add(key, value);
+    ASSERT_TRUE(ref);
+    ASSERT_TRUE(existed);
+  }
+}
+
+TEST(LRU, eviction) {
+  const unsigned SIZE = 3;
+  LRUTest cache;
+  cache.set_target_size(SIZE);
+
+  for (unsigned i = 0; i < SIZE; ++i) {
+    auto [ref, existed] = cache.add(i, i);
+    ASSERT_TRUE(ref && !existed);
+  }
+
+  {
+    auto [ref, existed] = cache.add(0, 0);
+    ASSERT_TRUE(ref && existed);
+  }
+
+  for (unsigned i = SIZE; i < (2*SIZE) - 1; ++i) {
+    auto [ref, existed]  = cache.add(i, i);
+    ASSERT_TRUE(ref && !existed);
+  }
+
+  {
+    auto [ref, existed] = cache.add(0, 0);
+    ASSERT_TRUE(ref && existed);
+  }
+
+  for (unsigned i = 1; i < SIZE; ++i) {
+    auto [ref, existed] = cache.add(i, i);
+    ASSERT_TRUE(ref && !existed);
+  }
+}
+
+TEST(LRU, eviction_live_ref) {
+  const unsigned SIZE = 3;
+  LRUTest cache;
+  cache.set_target_size(SIZE);
+
+  auto [live_ref, existed2] = cache.add(1, 1);
+  ASSERT_TRUE(live_ref && !existed2);
+
+  for (unsigned i = 0; i < SIZE; ++i) {
+    auto [ref, existed] = cache.add(i, i);
+    ASSERT_TRUE(ref);
+    if (i == 1) {
+      ASSERT_TRUE(existed);
+    } else {
+      ASSERT_FALSE(existed);
+    }
+  }
+
+  {
+    auto [ref, existed] = cache.add(0, 0);
+    ASSERT_TRUE(ref && existed);
+  }
+
+  for (unsigned i = SIZE; i < (2*SIZE) - 1; ++i) {
+    auto [ref, existed]  = cache.add(i, i);
+    ASSERT_TRUE(ref && !existed);
+  }
+
+  for (unsigned i = 0; i < SIZE; ++i) {
+    auto [ref, existed] = cache.add(i, i);
+    ASSERT_TRUE(ref);
+    if (i == 1) {
+      ASSERT_TRUE(existed);
+    } else {
+      ASSERT_FALSE(existed);
+    }
+  }
+}