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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: sw=2 ts=4 et :
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
// Avoid DMD-specific parts of MOZ_DEFINE_MALLOC_SIZE_OF
#undef MOZ_DMD
#include "nsIMemoryReporter.h"
#include "mozilla/Mutex.h"
#include "gtest/gtest.h"
//-----------------------------------------------------------------------------
static void AllocLockRecurseUnlockFree(int i) {
if (0 == i) return;
mozilla::Mutex* lock = new mozilla::Mutex("deadlockDetector.scalability.t1");
{
mozilla::MutexAutoLock _(*lock);
AllocLockRecurseUnlockFree(i - 1);
}
delete lock;
}
// This test creates a resource dependency chain N elements long, then
// frees all the resources in the chain.
TEST(DeadlockDetectorScalability, LengthNDepChain)
{
const int N = 1 << 14; // 16K
AllocLockRecurseUnlockFree(N);
ASSERT_TRUE(true);
}
//-----------------------------------------------------------------------------
// This test creates a single lock that is ordered < N resources, then
// repeatedly exercises this order k times.
//
// NB: It takes a minute or two to run so it is disabled by default.
TEST(DeadlockDetectorScalability, DISABLED_OneLockNDeps)
{
// NB: Using a larger test size to stress our traversal logic.
const int N = 1 << 17; // 131k
const int K = 100;
mozilla::Mutex* lock =
new mozilla::Mutex("deadlockDetector.scalability.t2.master");
mozilla::Mutex** locks = new mozilla::Mutex*[N];
if (!locks) MOZ_CRASH("couldn't allocate lock array");
for (int i = 0; i < N; ++i)
locks[i] = new mozilla::Mutex("deadlockDetector.scalability.t2.dep");
// establish orders
{
mozilla::MutexAutoLock m(*lock);
for (int i = 0; i < N; ++i) mozilla::MutexAutoLock s(*locks[i]);
}
// exercise order check
{
mozilla::MutexAutoLock m(*lock);
for (int i = 0; i < K; ++i)
for (int j = 0; j < N; ++j) mozilla::MutexAutoLock s(*locks[i]);
}
for (int i = 0; i < N; ++i) delete locks[i];
delete[] locks;
ASSERT_TRUE(true);
}
//-----------------------------------------------------------------------------
// This test creates N resources and adds the theoretical maximum number
// of dependencies, O(N^2). It then repeats that sequence of
// acquisitions k times. Finally, all resources are freed.
//
// It's very difficult to perform well on this test. It's put forth as a
// challenge problem.
TEST(DeadlockDetectorScalability, MaxDepsNsq)
{
const int N = 1 << 10; // 1k
const int K = 10;
mozilla::Mutex** locks = new mozilla::Mutex*[N];
if (!locks) MOZ_CRASH("couldn't allocate lock array");
for (int i = 0; i < N; ++i)
locks[i] = new mozilla::Mutex("deadlockDetector.scalability.t3");
for (int i = 0; i < N; ++i) {
mozilla::MutexAutoLock al1(*locks[i]);
for (int j = i + 1; j < N; ++j) mozilla::MutexAutoLock al2(*locks[j]);
}
for (int i = 0; i < K; ++i) {
for (int j = 0; j < N; ++j) {
mozilla::MutexAutoLock al1(*locks[j]);
for (int k = j + 1; k < N; ++k) mozilla::MutexAutoLock al2(*locks[k]);
}
}
for (int i = 0; i < N; ++i) delete locks[i];
delete[] locks;
ASSERT_TRUE(true);
}
//-----------------------------------------------------------------------------
// This test creates a single lock that is ordered < N resources. The
// resources are allocated, exercised K times, and deallocated one at
// a time.
TEST(DeadlockDetectorScalability, OneLockNDepsUsedSeveralTimes)
{
const size_t N = 1 << 17; // 131k
const size_t K = 3;
// Create master lock.
mozilla::Mutex* lock_1 =
new mozilla::Mutex("deadlockDetector.scalability.t4.master");
for (size_t n = 0; n < N; n++) {
// Create child lock.
mozilla::Mutex* lock_2 =
new mozilla::Mutex("deadlockDetector.scalability.t4.child");
// First lock the master.
mozilla::MutexAutoLock m(*lock_1);
// Now lock and unlock the child a few times.
for (size_t k = 0; k < K; k++) {
mozilla::MutexAutoLock c(*lock_2);
}
// Destroy the child lock.
delete lock_2;
}
// Cleanup the master lock.
delete lock_1;
ASSERT_TRUE(true);
}
//-----------------------------------------------------------------------------
MOZ_DEFINE_MALLOC_SIZE_OF(DeadlockDetectorMallocSizeOf)
// This is a simple test that exercises the deadlock detector memory reporting
// functionality.
TEST(DeadlockDetectorScalability, SizeOf)
{
size_t memory_used = mozilla::BlockingResourceBase::SizeOfDeadlockDetector(
DeadlockDetectorMallocSizeOf);
ASSERT_GT(memory_used, size_t(0));
}