import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

xpcom/tests/gtest/TestDeadlockDetectorScalability.cpp

@@ -0,0 +1,170 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: sw=4 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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// 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)
+        NS_RUNTIMEABORT("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)
+        NS_RUNTIMEABORT("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));
+}