Fri, 16 Jul 2010 21:33:21 -0700
6962947: shared TaskQueue statistics
Reviewed-by: tonyp, ysr
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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 *
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23 */
25 //
26 // psPromotionManager is used by a single thread to manage object survival
27 // during a scavenge. The promotion manager contains thread local data only.
28 //
29 // NOTE! Be carefull when allocating the stacks on cheap. If you are going
30 // to use a promotion manager in more than one thread, the stacks MUST be
31 // on cheap. This can lead to memory leaks, though, as they are not auto
32 // deallocated.
33 //
34 // FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate!
35 //
37 // Move to some global location
38 #define HAS_BEEN_MOVED 0x1501d01d
39 // End move to some global location
41 class MutableSpace;
42 class PSOldGen;
43 class ParCompactionManager;
45 class PSPromotionManager : public CHeapObj {
46 friend class PSScavenge;
47 friend class PSRefProcTaskExecutor;
48 private:
49 static PSPromotionManager** _manager_array;
50 static OopStarTaskQueueSet* _stack_array_depth;
51 static OopTaskQueueSet* _stack_array_breadth;
52 static PSOldGen* _old_gen;
53 static MutableSpace* _young_space;
55 #if TASKQUEUE_STATS
56 size_t _masked_pushes;
57 size_t _masked_steals;
58 size_t _arrays_chunked;
59 size_t _array_chunks_processed;
61 void print_taskqueue_stats(uint i) const;
62 void print_local_stats(uint i) const;
63 static void print_stats();
65 void reset_stats();
66 #endif // TASKQUEUE_STATS
68 PSYoungPromotionLAB _young_lab;
69 PSOldPromotionLAB _old_lab;
70 bool _young_gen_is_full;
71 bool _old_gen_is_full;
72 PrefetchQueue _prefetch_queue;
74 OopStarTaskQueue _claimed_stack_depth;
75 OverflowTaskQueue<oop> _claimed_stack_breadth;
77 bool _depth_first;
78 bool _totally_drain;
79 uint _target_stack_size;
81 uint _array_chunk_size;
82 uint _min_array_size_for_chunking;
84 // Accessors
85 static PSOldGen* old_gen() { return _old_gen; }
86 static MutableSpace* young_space() { return _young_space; }
88 inline static PSPromotionManager* manager_array(int index);
89 template <class T> inline void claim_or_forward_internal_depth(T* p);
90 template <class T> inline void claim_or_forward_internal_breadth(T* p);
92 // On the task queues we push reference locations as well as
93 // partially-scanned arrays (in the latter case, we push an oop to
94 // the from-space image of the array and the length on the
95 // from-space image indicates how many entries on the array we still
96 // need to scan; this is basically how ParNew does partial array
97 // scanning too). To be able to distinguish between reference
98 // locations and partially-scanned array oops we simply mask the
99 // latter oops with 0x01. The next three methods do the masking,
100 // unmasking, and checking whether the oop is masked or not. Notice
101 // that the signature of the mask and unmask methods looks a bit
102 // strange, as they accept and return different types (oop and
103 // oop*). This is because of the difference in types between what
104 // the task queue holds (oop*) and oops to partially-scanned arrays
105 // (oop). We do all the necessary casting in the mask / unmask
106 // methods to avoid sprinkling the rest of the code with more casts.
108 // These are added to the taskqueue so PS_CHUNKED_ARRAY_OOP_MASK (or any
109 // future masks) can't conflict with COMPRESSED_OOP_MASK
110 #define PS_CHUNKED_ARRAY_OOP_MASK 0x2
112 bool is_oop_masked(StarTask p) {
113 // If something is marked chunked it's always treated like wide oop*
114 return (((intptr_t)(oop*)p) & PS_CHUNKED_ARRAY_OOP_MASK) ==
115 PS_CHUNKED_ARRAY_OOP_MASK;
116 }
118 oop* mask_chunked_array_oop(oop obj) {
119 assert(!is_oop_masked((oop*) obj), "invariant");
120 oop* ret = (oop*) ((uintptr_t)obj | PS_CHUNKED_ARRAY_OOP_MASK);
121 assert(is_oop_masked(ret), "invariant");
122 return ret;
123 }
125 oop unmask_chunked_array_oop(StarTask p) {
126 assert(is_oop_masked(p), "invariant");
127 assert(!p.is_narrow(), "chunked array oops cannot be narrow");
128 oop *chunk = (oop*)p; // cast p to oop (uses conversion operator)
129 oop ret = oop((oop*)((uintptr_t)chunk & ~PS_CHUNKED_ARRAY_OOP_MASK));
130 assert(!is_oop_masked((oop*) ret), "invariant");
131 return ret;
132 }
134 template <class T> void process_array_chunk_work(oop obj,
135 int start, int end);
136 void process_array_chunk(oop old);
138 template <class T> void push_depth(T* p) {
139 assert(depth_first(), "pre-condition");
140 claimed_stack_depth()->push(p);
141 }
143 void push_breadth(oop o) {
144 assert(!depth_first(), "pre-condition");
145 claimed_stack_breadth()->push(o);
146 }
148 protected:
149 static OopStarTaskQueueSet* stack_array_depth() { return _stack_array_depth; }
150 static OopTaskQueueSet* stack_array_breadth() { return _stack_array_breadth; }
152 public:
153 // Static
154 static void initialize();
156 static void pre_scavenge();
157 static void post_scavenge();
159 static PSPromotionManager* gc_thread_promotion_manager(int index);
160 static PSPromotionManager* vm_thread_promotion_manager();
162 static bool steal_depth(int queue_num, int* seed, StarTask& t) {
163 return stack_array_depth()->steal(queue_num, seed, t);
164 }
166 static bool steal_breadth(int queue_num, int* seed, oop& t) {
167 return stack_array_breadth()->steal(queue_num, seed, t);
168 }
170 PSPromotionManager();
172 // Accessors
173 OopStarTaskQueue* claimed_stack_depth() {
174 return &_claimed_stack_depth;
175 }
176 OverflowTaskQueue<oop>* claimed_stack_breadth() {
177 return &_claimed_stack_breadth;
178 }
180 bool young_gen_is_full() { return _young_gen_is_full; }
182 bool old_gen_is_full() { return _old_gen_is_full; }
183 void set_old_gen_is_full(bool state) { _old_gen_is_full = state; }
185 // Promotion methods
186 oop copy_to_survivor_space(oop o, bool depth_first);
187 oop oop_promotion_failed(oop obj, markOop obj_mark);
189 void reset();
191 void flush_labs();
192 void drain_stacks(bool totally_drain) {
193 if (depth_first()) {
194 drain_stacks_depth(totally_drain);
195 } else {
196 drain_stacks_breadth(totally_drain);
197 }
198 }
199 public:
200 void drain_stacks_cond_depth() {
201 if (claimed_stack_depth()->size() > _target_stack_size) {
202 drain_stacks_depth(false);
203 }
204 }
205 void drain_stacks_depth(bool totally_drain);
206 void drain_stacks_breadth(bool totally_drain);
208 bool depth_first() const {
209 return _depth_first;
210 }
211 bool stacks_empty() {
212 return depth_first() ?
213 claimed_stack_depth()->is_empty() :
214 claimed_stack_breadth()->is_empty();
215 }
217 inline void process_popped_location_depth(StarTask p);
219 inline void flush_prefetch_queue();
220 template <class T> inline void claim_or_forward_depth(T* p);
221 template <class T> inline void claim_or_forward_breadth(T* p);
223 TASKQUEUE_STATS_ONLY(inline void record_steal(StarTask& p);)
224 };