Wed, 20 Aug 2014 08:41:15 -0400
8054546: NMT2 leaks memory
Summary: Fixed memory leak in NMT by baselining memory in c heap instead of an arena.
Reviewed-by: coleenp, minqi
1 /*
2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #ifndef SHARE_VM_SERVICES_MALLOC_TRACKER_HPP
26 #define SHARE_VM_SERVICES_MALLOC_TRACKER_HPP
28 #if INCLUDE_NMT
30 #include "memory/allocation.hpp"
31 #include "runtime/atomic.hpp"
32 #include "services/nmtCommon.hpp"
33 #include "utilities/nativeCallStack.hpp"
35 /*
36 * This counter class counts memory allocation and deallocation,
37 * records total memory allocation size and number of allocations.
38 * The counters are updated atomically.
39 */
40 class MemoryCounter VALUE_OBJ_CLASS_SPEC {
41 private:
42 size_t _count;
43 size_t _size;
45 DEBUG_ONLY(size_t _peak_count;)
46 DEBUG_ONLY(size_t _peak_size; )
48 public:
49 MemoryCounter() : _count(0), _size(0) {
50 DEBUG_ONLY(_peak_count = 0;)
51 DEBUG_ONLY(_peak_size = 0;)
52 }
54 // Reset counters
55 void reset() {
56 _size = 0;
57 _count = 0;
58 DEBUG_ONLY(_peak_size = 0;)
59 DEBUG_ONLY(_peak_count = 0;)
60 }
62 inline void allocate(size_t sz) {
63 Atomic::add(1, (volatile MemoryCounterType*)&_count);
64 if (sz > 0) {
65 Atomic::add((MemoryCounterType)sz, (volatile MemoryCounterType*)&_size);
66 DEBUG_ONLY(_peak_size = MAX2(_peak_size, _size));
67 }
68 DEBUG_ONLY(_peak_count = MAX2(_peak_count, _count);)
69 }
71 inline void deallocate(size_t sz) {
72 assert(_count > 0, "Negative counter");
73 assert(_size >= sz, "Negative size");
74 Atomic::add(-1, (volatile MemoryCounterType*)&_count);
75 if (sz > 0) {
76 Atomic::add(-(MemoryCounterType)sz, (volatile MemoryCounterType*)&_size);
77 }
78 }
80 inline void resize(long sz) {
81 if (sz != 0) {
82 Atomic::add((MemoryCounterType)sz, (volatile MemoryCounterType*)&_size);
83 DEBUG_ONLY(_peak_size = MAX2(_size, _peak_size);)
84 }
85 }
87 inline size_t count() const { return _count; }
88 inline size_t size() const { return _size; }
89 DEBUG_ONLY(inline size_t peak_count() const { return _peak_count; })
90 DEBUG_ONLY(inline size_t peak_size() const { return _peak_size; })
92 };
94 /*
95 * Malloc memory used by a particular subsystem.
96 * It includes the memory acquired through os::malloc()
97 * call and arena's backing memory.
98 */
99 class MallocMemory VALUE_OBJ_CLASS_SPEC {
100 private:
101 MemoryCounter _malloc;
102 MemoryCounter _arena;
104 public:
105 MallocMemory() { }
107 inline void record_malloc(size_t sz) {
108 _malloc.allocate(sz);
109 }
111 inline void record_free(size_t sz) {
112 _malloc.deallocate(sz);
113 }
115 inline void record_new_arena() {
116 _arena.allocate(0);
117 }
119 inline void record_arena_free() {
120 _arena.deallocate(0);
121 }
123 inline void record_arena_size_change(long sz) {
124 _arena.resize(sz);
125 }
127 void reset() {
128 _malloc.reset();
129 _arena.reset();
130 }
132 inline size_t malloc_size() const { return _malloc.size(); }
133 inline size_t malloc_count() const { return _malloc.count();}
134 inline size_t arena_size() const { return _arena.size(); }
135 inline size_t arena_count() const { return _arena.count(); }
137 DEBUG_ONLY(inline const MemoryCounter& malloc_counter() const { return _malloc; })
138 DEBUG_ONLY(inline const MemoryCounter& arena_counter() const { return _arena; })
139 };
141 class MallocMemorySummary;
143 // A snapshot of malloc'd memory, includes malloc memory
144 // usage by types and memory used by tracking itself.
145 class MallocMemorySnapshot : public ResourceObj {
146 friend class MallocMemorySummary;
148 private:
149 MallocMemory _malloc[mt_number_of_types];
150 MemoryCounter _tracking_header;
153 public:
154 inline MallocMemory* by_type(MEMFLAGS flags) {
155 int index = NMTUtil::flag_to_index(flags);
156 return &_malloc[index];
157 }
159 inline MallocMemory* by_index(int index) {
160 assert(index >= 0, "Index out of bound");
161 assert(index < mt_number_of_types, "Index out of bound");
162 return &_malloc[index];
163 }
165 inline MemoryCounter* malloc_overhead() {
166 return &_tracking_header;
167 }
169 // Total malloc'd memory amount
170 size_t total() const;
171 // Total malloc'd memory used by arenas
172 size_t total_arena() const;
174 inline size_t thread_count() const {
175 MallocMemorySnapshot* s = const_cast<MallocMemorySnapshot*>(this);
176 return s->by_type(mtThreadStack)->malloc_count();
177 }
179 void reset();
181 void copy_to(MallocMemorySnapshot* s) {
182 s->_tracking_header = _tracking_header;
183 for (int index = 0; index < mt_number_of_types; index ++) {
184 s->_malloc[index] = _malloc[index];
185 }
186 }
188 // Make adjustment by subtracting chunks used by arenas
189 // from total chunks to get total free chunk size
190 void make_adjustment();
191 };
193 /*
194 * This class is for collecting malloc statistics at summary level
195 */
196 class MallocMemorySummary : AllStatic {
197 private:
198 // Reserve memory for placement of MallocMemorySnapshot object
199 static size_t _snapshot[CALC_OBJ_SIZE_IN_TYPE(MallocMemorySnapshot, size_t)];
201 public:
202 static void initialize();
204 static inline void record_malloc(size_t size, MEMFLAGS flag) {
205 as_snapshot()->by_type(flag)->record_malloc(size);
206 }
208 static inline void record_free(size_t size, MEMFLAGS flag) {
209 as_snapshot()->by_type(flag)->record_free(size);
210 }
212 static inline void record_new_arena(MEMFLAGS flag) {
213 as_snapshot()->by_type(flag)->record_new_arena();
214 }
216 static inline void record_arena_free(MEMFLAGS flag) {
217 as_snapshot()->by_type(flag)->record_arena_free();
218 }
220 static inline void record_arena_size_change(long size, MEMFLAGS flag) {
221 as_snapshot()->by_type(flag)->record_arena_size_change(size);
222 }
224 static void snapshot(MallocMemorySnapshot* s) {
225 as_snapshot()->copy_to(s);
226 s->make_adjustment();
227 }
229 // Record memory used by malloc tracking header
230 static inline void record_new_malloc_header(size_t sz) {
231 as_snapshot()->malloc_overhead()->allocate(sz);
232 }
234 static inline void record_free_malloc_header(size_t sz) {
235 as_snapshot()->malloc_overhead()->deallocate(sz);
236 }
238 // The memory used by malloc tracking headers
239 static inline size_t tracking_overhead() {
240 return as_snapshot()->malloc_overhead()->size();
241 }
243 // Reset all counters to zero
244 static void reset() {
245 as_snapshot()->reset();
246 }
248 static MallocMemorySnapshot* as_snapshot() {
249 return (MallocMemorySnapshot*)_snapshot;
250 }
251 };
254 /*
255 * Malloc tracking header.
256 * To satisfy malloc alignment requirement, NMT uses 2 machine words for tracking purpose,
257 * which ensures 8-bytes alignment on 32-bit systems and 16-bytes on 64-bit systems (Product build).
258 */
260 class MallocHeader VALUE_OBJ_CLASS_SPEC {
261 #ifdef _LP64
262 size_t _size : 62;
263 size_t _level : 2;
264 size_t _flags : 8;
265 size_t _pos_idx : 16;
266 size_t _bucket_idx: 40;
267 #define MAX_MALLOCSITE_TABLE_SIZE ((size_t)1 << 40)
268 #define MAX_BUCKET_LENGTH ((size_t)(1 << 16))
269 #define MAX_MALLOC_SIZE (((size_t)1 << 62) - 1)
270 #else
271 size_t _size : 30;
272 size_t _level : 2;
273 size_t _flags : 8;
274 size_t _pos_idx : 8;
275 size_t _bucket_idx: 16;
276 #define MAX_MALLOCSITE_TABLE_SIZE ((size_t)(1 << 16))
277 #define MAX_BUCKET_LENGTH ((size_t)(1 << 8))
278 // Max malloc size = 1GB - 1 on 32 bit system, such has total 4GB memory
279 #define MAX_MALLOC_SIZE ((size_t)(1 << 30) - 1)
280 #endif // _LP64
282 public:
283 // Summary tracking header
284 MallocHeader(size_t size, MEMFLAGS flags) {
285 assert(sizeof(MallocHeader) == sizeof(void*) * 2,
286 "Wrong header size");
288 _level = NMT_summary;
289 _flags = flags;
290 set_size(size);
291 MallocMemorySummary::record_malloc(size, flags);
292 MallocMemorySummary::record_new_malloc_header(sizeof(MallocHeader));
293 }
294 // Detail tracking header
295 MallocHeader(size_t size, MEMFLAGS flags, const NativeCallStack& stack) {
296 assert(sizeof(MallocHeader) == sizeof(void*) * 2,
297 "Wrong header size");
299 _level = NMT_detail;
300 _flags = flags;
301 set_size(size);
302 size_t bucket_idx;
303 size_t pos_idx;
304 if (record_malloc_site(stack, size, &bucket_idx, &pos_idx)) {
305 assert(bucket_idx <= MAX_MALLOCSITE_TABLE_SIZE, "Overflow bucket index");
306 assert(pos_idx <= MAX_BUCKET_LENGTH, "Overflow bucket position index");
307 _bucket_idx = bucket_idx;
308 _pos_idx = pos_idx;
309 }
310 MallocMemorySummary::record_malloc(size, flags);
311 MallocMemorySummary::record_new_malloc_header(sizeof(MallocHeader));
312 }
313 // Minimal tracking header
314 MallocHeader() {
315 assert(sizeof(MallocHeader) == sizeof(void*) * 2,
316 "Wrong header size");
318 _level = (unsigned short)NMT_minimal;
319 }
321 inline NMT_TrackingLevel tracking_level() const {
322 return (NMT_TrackingLevel)_level;
323 }
325 inline size_t size() const { return _size; }
326 inline MEMFLAGS flags() const { return (MEMFLAGS)_flags; }
327 bool get_stack(NativeCallStack& stack) const;
329 // Cleanup tracking information before the memory is released.
330 void release() const;
332 private:
333 inline void set_size(size_t size) {
334 assert(size <= MAX_MALLOC_SIZE, "Malloc size too large, should use virtual memory?");
335 _size = size;
336 }
337 bool record_malloc_site(const NativeCallStack& stack, size_t size,
338 size_t* bucket_idx, size_t* pos_idx) const;
339 };
342 // Main class called from MemTracker to track malloc activities
343 class MallocTracker : AllStatic {
344 public:
345 // Initialize malloc tracker for specific tracking level
346 static bool initialize(NMT_TrackingLevel level);
348 static bool transition(NMT_TrackingLevel from, NMT_TrackingLevel to);
350 // malloc tracking header size for specific tracking level
351 static inline size_t malloc_header_size(NMT_TrackingLevel level) {
352 return (level == NMT_off) ? 0 : sizeof(MallocHeader);
353 }
355 // Parameter name convention:
356 // memblock : the beginning address for user data
357 // malloc_base: the beginning address that includes malloc tracking header
358 //
359 // The relationship:
360 // memblock = (char*)malloc_base + sizeof(nmt header)
361 //
363 // Record malloc on specified memory block
364 static void* record_malloc(void* malloc_base, size_t size, MEMFLAGS flags,
365 const NativeCallStack& stack, NMT_TrackingLevel level);
367 // Record free on specified memory block
368 static void* record_free(void* memblock);
370 // Get tracking level of specified memory block
371 static inline NMT_TrackingLevel get_memory_tracking_level(void* memblock);
374 // Offset memory address to header address
375 static inline void* get_base(void* memblock);
376 static inline void* get_base(void* memblock, NMT_TrackingLevel level) {
377 if (memblock == NULL || level == NMT_off) return memblock;
378 return (char*)memblock - malloc_header_size(level);
379 }
381 // Get memory size
382 static inline size_t get_size(void* memblock) {
383 MallocHeader* header = malloc_header(memblock);
384 assert(header->tracking_level() >= NMT_summary,
385 "Wrong tracking level");
386 return header->size();
387 }
389 // Get memory type
390 static inline MEMFLAGS get_flags(void* memblock) {
391 MallocHeader* header = malloc_header(memblock);
392 assert(header->tracking_level() >= NMT_summary,
393 "Wrong tracking level");
394 return header->flags();
395 }
397 // Get header size
398 static inline size_t get_header_size(void* memblock) {
399 return (memblock == NULL) ? 0 : sizeof(MallocHeader);
400 }
402 static inline void record_new_arena(MEMFLAGS flags) {
403 MallocMemorySummary::record_new_arena(flags);
404 }
406 static inline void record_arena_free(MEMFLAGS flags) {
407 MallocMemorySummary::record_arena_free(flags);
408 }
410 static inline void record_arena_size_change(int size, MEMFLAGS flags) {
411 MallocMemorySummary::record_arena_size_change(size, flags);
412 }
413 private:
414 static inline MallocHeader* malloc_header(void *memblock) {
415 assert(memblock != NULL, "NULL pointer");
416 MallocHeader* header = (MallocHeader*)((char*)memblock - sizeof(MallocHeader));
417 assert(header->tracking_level() >= NMT_minimal, "Bad header");
418 return header;
419 }
420 };
422 #endif // INCLUDE_NMT
425 #endif //SHARE_VM_SERVICES_MALLOC_TRACKER_HPP