blob: 78c4f84ce1ff879739e51aa238e7b561c2150cfc [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stddef.h>
#include <stdio.h>
#include "base/compiler_specific.h"
#include "base/logging.h"
#include "base/process/process_metrics.h"
#include "base/sys_info.h"
#include "build/build_config.h"
#include "testing/gtest/include/gtest/gtest.h"
#if defined(USE_TCMALLOC)
namespace {
using std::min;
#ifdef NDEBUG
// We wrap malloc and free in noinline functions to ensure that we test the real
// implementation of the allocator. Otherwise, the compiler may specifically
// recognize the calls to malloc and free in our tests and optimize them away.
NOINLINE void* TCMallocDoMallocForTest(size_t size) {
return malloc(size);
}
NOINLINE void TCMallocDoFreeForTest(void* ptr) {
free(ptr);
}
#endif
// Fill a buffer of the specified size with a predetermined pattern
static void Fill(unsigned char* buffer, int n) {
for (int i = 0; i < n; i++) {
buffer[i] = (i & 0xff);
}
}
// Check that the specified buffer has the predetermined pattern
// generated by Fill()
static bool Valid(unsigned char* buffer, int n) {
for (int i = 0; i < n; i++) {
if (buffer[i] != (i & 0xff)) {
return false;
}
}
return true;
}
// Return the next interesting size/delta to check. Returns -1 if no more.
static int NextSize(int size) {
if (size < 100)
return size + 1;
if (size < 100000) {
// Find next power of two
int power = 1;
while (power < size)
power <<= 1;
// Yield (power-1, power, power+1)
if (size < power - 1)
return power - 1;
if (size == power - 1)
return power;
CHECK_EQ(size, power);
return power + 1;
} else {
return -1;
}
}
static void TestCalloc(size_t n, size_t s, bool ok) {
char* p = reinterpret_cast<char*>(calloc(n, s));
if (!ok) {
EXPECT_EQ(nullptr, p) << "calloc(n, s) should not succeed";
} else {
EXPECT_NE(reinterpret_cast<void*>(NULL), p)
<< "calloc(n, s) should succeed";
for (size_t i = 0; i < n * s; i++) {
EXPECT_EQ('\0', p[i]);
}
free(p);
}
}
bool IsLowMemoryDevice() {
return base::SysInfo::AmountOfPhysicalMemory() <= 256LL * 1024 * 1024;
}
} // namespace
TEST(TCMallocTest, Malloc) {
// Try allocating data with a bunch of alignments and sizes
for (int size = 1; size < 1048576; size *= 2) {
unsigned char* ptr = reinterpret_cast<unsigned char*>(malloc(size));
// Should be 2 byte aligned
EXPECT_EQ(0u, reinterpret_cast<uintptr_t>(ptr) & 1);
Fill(ptr, size);
EXPECT_TRUE(Valid(ptr, size));
free(ptr);
}
}
TEST(TCMallocTest, Calloc) {
TestCalloc(0, 0, true);
TestCalloc(0, 1, true);
TestCalloc(1, 1, true);
TestCalloc(1 << 10, 0, true);
TestCalloc(1 << 20, 0, true);
TestCalloc(0, 1 << 10, true);
TestCalloc(0, 1 << 20, true);
TestCalloc(1 << 20, 2, true);
TestCalloc(2, 1 << 20, true);
TestCalloc(1000, 1000, true);
}
#ifdef NDEBUG
// This makes sure that reallocing a small number of bytes in either
// direction doesn't cause us to allocate new memory. Tcmalloc in debug mode
// does not follow this.
TEST(TCMallocTest, ReallocSmallDelta) {
int start_sizes[] = {100, 1000, 10000, 100000};
int deltas[] = {1, -2, 4, -8, 16, -32, 64, -128};
for (unsigned s = 0; s < sizeof(start_sizes) / sizeof(*start_sizes); ++s) {
void* p = malloc(start_sizes[s]);
ASSERT_TRUE(p);
// The larger the start-size, the larger the non-reallocing delta.
for (unsigned d = 0; d < s * 2; ++d) {
void* new_p = realloc(p, start_sizes[s] + deltas[d]);
ASSERT_EQ(p, new_p); // realloc should not allocate new memory
}
// Test again, but this time reallocing smaller first.
for (unsigned d = 0; d < s * 2; ++d) {
void* new_p = realloc(p, start_sizes[s] - deltas[d]);
ASSERT_EQ(p, new_p); // realloc should not allocate new memory
}
free(p);
}
}
#endif
TEST(TCMallocTest, Realloc) {
for (int src_size = 0; src_size >= 0; src_size = NextSize(src_size)) {
for (int dst_size = 0; dst_size >= 0; dst_size = NextSize(dst_size)) {
unsigned char* src = reinterpret_cast<unsigned char*>(malloc(src_size));
Fill(src, src_size);
unsigned char* dst =
reinterpret_cast<unsigned char*>(realloc(src, dst_size));
EXPECT_TRUE(Valid(dst, min(src_size, dst_size)));
Fill(dst, dst_size);
EXPECT_TRUE(Valid(dst, dst_size));
if (dst != nullptr)
free(dst);
}
}
// The logic below tries to allocate kNumEntries * 9000 ~= 130 MB of memory.
// This would cause the test to crash on low memory devices with no VM
// overcommit (e.g., chromecast).
if (IsLowMemoryDevice())
return;
// Now make sure realloc works correctly even when we overflow the
// packed cache, so some entries are evicted from the cache.
// The cache has 2^12 entries, keyed by page number.
const int kNumEntries = 1 << 14;
int** p = reinterpret_cast<int**>(malloc(sizeof(*p) * kNumEntries));
int sum = 0;
for (int i = 0; i < kNumEntries; i++) {
// no page size is likely to be bigger than 8192?
p[i] = reinterpret_cast<int*>(malloc(8192));
p[i][1000] = i; // use memory deep in the heart of p
}
for (int i = 0; i < kNumEntries; i++) {
p[i] = reinterpret_cast<int*>(realloc(p[i], 9000));
}
for (int i = 0; i < kNumEntries; i++) {
sum += p[i][1000];
free(p[i]);
}
EXPECT_EQ(kNumEntries / 2 * (kNumEntries - 1), sum); // assume kNE is even
free(p);
}
#ifdef NDEBUG
TEST(TCMallocFreeTest, BadPointerInFirstPageOfTheLargeObject) {
const size_t kPageSize = base::GetPageSize();
char* p =
reinterpret_cast<char*>(TCMallocDoMallocForTest(10 * kPageSize + 1));
for (unsigned offset = 1; offset < kPageSize; offset <<= 1) {
ASSERT_DEATH(TCMallocDoFreeForTest(p + offset),
"Pointer is not pointing to the start of a span");
}
TCMallocDoFreeForTest(p);
}
// TODO(ssid): Fix flakiness and enable the test, crbug.com/571549.
TEST(TCMallocFreeTest, DISABLED_BadPageAlignedPointerInsideLargeObject) {
const size_t kPageSize = base::GetPageSize();
const size_t kMaxSize = 10 * kPageSize;
char* p = reinterpret_cast<char*>(TCMallocDoMallocForTest(kMaxSize + 1));
for (unsigned offset = kPageSize; offset < kMaxSize; offset += kPageSize) {
// Only the first and last page of a span are in heap map. So for others
// tcmalloc will give a general error of invalid pointer.
ASSERT_DEATH(TCMallocDoFreeForTest(p + offset), "");
}
ASSERT_DEATH(TCMallocDoFreeForTest(p + kMaxSize),
"Pointer is not pointing to the start of a span");
TCMallocDoFreeForTest(p);
}
TEST(TCMallocFreeTest, DoubleFreeLargeObject) {
const size_t kMaxSize = 10 * base::GetPageSize();
char* p = reinterpret_cast<char*>(TCMallocDoMallocForTest(kMaxSize + 1));
ASSERT_DEATH(TCMallocDoFreeForTest(p); TCMallocDoFreeForTest(p),
"Object was not in-use");
}
TEST(TCMallocFreeTest, DoubleFreeSmallObject) {
const size_t kPageSize = base::GetPageSize();
for (size_t size = 1; size <= kPageSize; size <<= 1) {
char* p = reinterpret_cast<char*>(TCMallocDoMallocForTest(size));
ASSERT_DEATH(TCMallocDoFreeForTest(p); TCMallocDoFreeForTest(p),
"Circular loop in list detected");
}
}
#endif // NDEBUG
#endif