1 /*
2 The Hoard Multiprocessor Memory Allocator
3 www.hoard.org
4
5 Author: Emery Berger, http://www.emeryberger.org
6
7 Copyright (c) 1998-2019 Emery Berger
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22
23 */
24
25 #if !defined(__APPLE__)
26 #error "This file is intended for use with MacOS systems only."
27 #endif
28
29 #include <dlfcn.h>
30 #include <pthread.h>
31 #include <utility>
32
33 #include "Heap-Layers/heaplayers.h"
34 #include "hoard/hoardtlab.h"
35
36 extern Hoard::HoardHeapType * getMainHoardHeap();
37
38 static pthread_key_t theHeapKey;
39 static pthread_once_t key_once = PTHREAD_ONCE_INIT;
40
41 // Called when the thread goes away. This function clears out the
42 // TLAB and then reclaims the memory allocated to hold it.
43
deleteThatHeap(void * p)44 static void deleteThatHeap(void * p) {
45 reinterpret_cast<TheCustomHeapType *>(p)->clear();
46 getMainHoardHeap()->free(p);
47
48 // Relinquish the assigned heap.
49 getMainHoardHeap()->releaseHeap();
50 }
51
make_heap_key()52 static void make_heap_key() {
53 if (pthread_key_create(&theHeapKey, deleteThatHeap) != 0) {
54 // This should never happen.
55 }
56 }
57
58 static bool initializedTSD = false;
59
initTSD()60 static bool initTSD() {
61 if (!initializedTSD) {
62 // Ensure that the key is initialized -- once.
63 pthread_once(&key_once, make_heap_key);
64 initializedTSD = true;
65 }
66 return true;
67 }
68
isCustomHeapInitialized()69 bool isCustomHeapInitialized() {
70 return initializedTSD;
71 }
72
initializeCustomHeap()73 static TheCustomHeapType * initializeCustomHeap() {
74 TheCustomHeapType * heap =
75 reinterpret_cast<TheCustomHeapType *>(pthread_getspecific(theHeapKey));
76 if (heap == NULL) {
77 // Defensive programming in case this is called twice.
78 // Allocate a per-thread heap.
79 size_t sz = sizeof(TheCustomHeapType);
80 char * mh = reinterpret_cast<char *>(getMainHoardHeap()->malloc(sz));
81 heap = new (mh) TheCustomHeapType(getMainHoardHeap());
82 // Store it in the appropriate thread-local area.
83 pthread_setspecific(theHeapKey, heap);
84 }
85 return heap;
86 }
87
getCustomHeap()88 TheCustomHeapType * getCustomHeap() {
89 initTSD();
90 // Allocate a per-thread heap.
91 TheCustomHeapType * heap =
92 reinterpret_cast<TheCustomHeapType *>(pthread_getspecific(theHeapKey));
93 if (heap == NULL) {
94 heap = initializeCustomHeap();
95 }
96 return heap;
97 }
98
99
100 //
101 // Intercept thread creation and destruction to flush the TLABs.
102 //
103
104
105 extern "C" {
106 typedef void * (*threadFunctionType)(void * arg);
107 }
108
109 // A special routine we call on thread exits to free up some resources.
exitRoutine()110 static void exitRoutine() {
111 TheCustomHeapType * heap = getCustomHeap();
112
113 // Clear the TLAB's buffer.
114 heap->clear();
115
116 // Relinquish the assigned heap.
117 getMainHoardHeap()->releaseHeap();
118 }
119
120 extern "C" {
startMeUp(void * a)121 static inline void * startMeUp(void * a) {
122 // Make sure that the custom heap has been initialized,
123 // then find an unused process heap for this thread, if possible.
124 getCustomHeap();
125 getMainHoardHeap()->findUnusedHeap();
126
127 // Extract the pair elements (function, argument).
128 pair<threadFunctionType, void *> * z
129 = reinterpret_cast<pair<threadFunctionType, void *> *>(a);
130
131 threadFunctionType fun = z->first;
132 void * arg = z->second;
133
134 // Execute the function.
135 void * result = (*fun)(arg);
136
137 // We're done: free up resources.
138 exitRoutine();
139 getCustomHeap()->free(a);
140 return result;
141 }
142 }
143
144
145 extern volatile bool anyThreadCreated;
146
147
148 // Intercept thread creation. We need this to first associate
149 // a heap with the thread and instantiate the thread-specific heap
150 // (TLAB). When the thread ends, we relinquish the assigned heap and
151 // free up the TLAB.
152
153
xxpthread_exit(void * value_ptr)154 extern "C" void xxpthread_exit(void * value_ptr) {
155 // Do necessary clean-up of the TLAB and get out.
156 exitRoutine();
157 pthread_exit(value_ptr);
158 }
159
xxpthread_create(pthread_t * thread,const pthread_attr_t * attr,void * (* start_routine)(void *),void * arg)160 extern "C" int xxpthread_create(pthread_t *thread,
161 const pthread_attr_t *attr,
162 void * (*start_routine)(void *),
163 void * arg) {
164 // Force initialization of the TLAB before our first thread is created.
165 static TheCustomHeapType * t = getCustomHeap();
166
167 anyThreadCreated = true;
168
169 pair<threadFunctionType, void *> * args =
170 new (t->malloc(sizeof(pair<threadFunctionType, void *>)))
171 pair<threadFunctionType, void *>(start_routine, arg);
172
173 int result = pthread_create(thread, attr, startMeUp, args);
174 return result;
175 }
176
177
178 MAC_INTERPOSE(xxpthread_create, pthread_create);
179 MAC_INTERPOSE(xxpthread_exit, pthread_exit);
180
181
182
183