1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
2 * vim: sw=2 ts=4 et :
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7 // Avoid DMD-specific parts of MOZ_DEFINE_MALLOC_SIZE_OF
8 #undef MOZ_DMD
9
10 #include "nsIMemoryReporter.h"
11 #include "mozilla/Mutex.h"
12
13 #include "gtest/gtest.h"
14
15 //-----------------------------------------------------------------------------
16
AllocLockRecurseUnlockFree(int i)17 static void AllocLockRecurseUnlockFree(int i) {
18 if (0 == i) return;
19
20 mozilla::Mutex* lock = new mozilla::Mutex("deadlockDetector.scalability.t1");
21 {
22 mozilla::MutexAutoLock _(*lock);
23 AllocLockRecurseUnlockFree(i - 1);
24 }
25 delete lock;
26 }
27
28 // This test creates a resource dependency chain N elements long, then
29 // frees all the resources in the chain.
TEST(DeadlockDetectorScalability,LengthNDepChain)30 TEST(DeadlockDetectorScalability, LengthNDepChain)
31 {
32 const int N = 1 << 14; // 16K
33 AllocLockRecurseUnlockFree(N);
34 ASSERT_TRUE(true);
35 }
36
37 //-----------------------------------------------------------------------------
38
39 // This test creates a single lock that is ordered < N resources, then
40 // repeatedly exercises this order k times.
41 //
42 // NB: It takes a minute or two to run so it is disabled by default.
TEST(DeadlockDetectorScalability,DISABLED_OneLockNDeps)43 TEST(DeadlockDetectorScalability, DISABLED_OneLockNDeps)
44 {
45 // NB: Using a larger test size to stress our traversal logic.
46 const int N = 1 << 17; // 131k
47 const int K = 100;
48
49 mozilla::Mutex* lock =
50 new mozilla::Mutex("deadlockDetector.scalability.t2.master");
51 mozilla::Mutex** locks = new mozilla::Mutex*[N];
52 if (!locks) MOZ_CRASH("couldn't allocate lock array");
53
54 for (int i = 0; i < N; ++i)
55 locks[i] = new mozilla::Mutex("deadlockDetector.scalability.t2.dep");
56
57 // establish orders
58 {
59 mozilla::MutexAutoLock m(*lock);
60 for (int i = 0; i < N; ++i) mozilla::MutexAutoLock s(*locks[i]);
61 }
62
63 // exercise order check
64 {
65 mozilla::MutexAutoLock m(*lock);
66 for (int i = 0; i < K; ++i)
67 for (int j = 0; j < N; ++j) mozilla::MutexAutoLock s(*locks[i]);
68 }
69
70 for (int i = 0; i < N; ++i) delete locks[i];
71 delete[] locks;
72
73 ASSERT_TRUE(true);
74 }
75
76 //-----------------------------------------------------------------------------
77
78 // This test creates N resources and adds the theoretical maximum number
79 // of dependencies, O(N^2). It then repeats that sequence of
80 // acquisitions k times. Finally, all resources are freed.
81 //
82 // It's very difficult to perform well on this test. It's put forth as a
83 // challenge problem.
84
TEST(DeadlockDetectorScalability,MaxDepsNsq)85 TEST(DeadlockDetectorScalability, MaxDepsNsq)
86 {
87 const int N = 1 << 10; // 1k
88 const int K = 10;
89
90 mozilla::Mutex** locks = new mozilla::Mutex*[N];
91 if (!locks) MOZ_CRASH("couldn't allocate lock array");
92
93 for (int i = 0; i < N; ++i)
94 locks[i] = new mozilla::Mutex("deadlockDetector.scalability.t3");
95
96 for (int i = 0; i < N; ++i) {
97 mozilla::MutexAutoLock al1(*locks[i]);
98 for (int j = i + 1; j < N; ++j) mozilla::MutexAutoLock al2(*locks[j]);
99 }
100
101 for (int i = 0; i < K; ++i) {
102 for (int j = 0; j < N; ++j) {
103 mozilla::MutexAutoLock al1(*locks[j]);
104 for (int k = j + 1; k < N; ++k) mozilla::MutexAutoLock al2(*locks[k]);
105 }
106 }
107
108 for (int i = 0; i < N; ++i) delete locks[i];
109 delete[] locks;
110
111 ASSERT_TRUE(true);
112 }
113
114 //-----------------------------------------------------------------------------
115
116 // This test creates a single lock that is ordered < N resources. The
117 // resources are allocated, exercised K times, and deallocated one at
118 // a time.
119
TEST(DeadlockDetectorScalability,OneLockNDepsUsedSeveralTimes)120 TEST(DeadlockDetectorScalability, OneLockNDepsUsedSeveralTimes)
121 {
122 const size_t N = 1 << 17; // 131k
123 const size_t K = 3;
124
125 // Create master lock.
126 mozilla::Mutex* lock_1 =
127 new mozilla::Mutex("deadlockDetector.scalability.t4.master");
128 for (size_t n = 0; n < N; n++) {
129 // Create child lock.
130 mozilla::Mutex* lock_2 =
131 new mozilla::Mutex("deadlockDetector.scalability.t4.child");
132
133 // First lock the master.
134 mozilla::MutexAutoLock m(*lock_1);
135
136 // Now lock and unlock the child a few times.
137 for (size_t k = 0; k < K; k++) {
138 mozilla::MutexAutoLock c(*lock_2);
139 }
140
141 // Destroy the child lock.
142 delete lock_2;
143 }
144
145 // Cleanup the master lock.
146 delete lock_1;
147
148 ASSERT_TRUE(true);
149 }
150
151 //-----------------------------------------------------------------------------
152
153 MOZ_DEFINE_MALLOC_SIZE_OF(DeadlockDetectorMallocSizeOf)
154
155 // This is a simple test that exercises the deadlock detector memory reporting
156 // functionality.
TEST(DeadlockDetectorScalability,SizeOf)157 TEST(DeadlockDetectorScalability, SizeOf)
158 {
159 size_t memory_used = mozilla::BlockingResourceBase::SizeOfDeadlockDetector(
160 DeadlockDetectorMallocSizeOf);
161
162 ASSERT_GT(memory_used, size_t(0));
163 }
164