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 */
24
25 #ifndef SHARE_VM_GC_G1_G1ALLOCREGION_HPP
26 #define SHARE_VM_GC_G1_G1ALLOCREGION_HPP
27
28 #include "gc/g1/heapRegion.hpp"
29 #include "gc/g1/g1EvacStats.hpp"
30 #include "gc/g1/g1InCSetState.hpp"
31
32 class G1CollectedHeap;
33
34 // 0 -> no tracing, 1 -> basic tracing, 2 -> basic + allocation tracing
35 #define G1_ALLOC_REGION_TRACING 0
36
37 class ar_ext_msg;
38
39 // A class that holds a region that is active in satisfying allocation
40 // requests, potentially issued in parallel. When the active region is
41 // full it will be retired and replaced with a new one. The
42 // implementation assumes that fast-path allocations will be lock-free
43 // and a lock will need to be taken when the active region needs to be
44 // replaced.
45
46 class G1AllocRegion VALUE_OBJ_CLASS_SPEC {
47 friend class ar_ext_msg;
48
49 private:
50 // The active allocating region we are currently allocating out
51 // of. The invariant is that if this object is initialized (i.e.,
52 // init() has been called and release() has not) then _alloc_region
53 // is either an active allocating region or the dummy region (i.e.,
54 // it can never be NULL) and this object can be used to satisfy
55 // allocation requests. If this object is not initialized
56 // (i.e. init() has not been called or release() has been called)
57 // then _alloc_region is NULL and this object should not be used to
58 // satisfy allocation requests (it was done this way to force the
59 // correct use of init() and release()).
60 HeapRegion* volatile _alloc_region;
61
62 // Allocation context associated with this alloc region.
63 AllocationContext_t _allocation_context;
64
65 // It keeps track of the distinct number of regions that are used
66 // for allocation in the active interval of this object, i.e.,
67 // between a call to init() and a call to release(). The count
114 size_t* actual_word_size,
115 bool bot_updates);
116
117 // Ensure that the region passed as a parameter has been filled up
118 // so that noone else can allocate out of it any more.
119 // Returns the number of bytes that have been wasted by filled up
120 // the space.
121 static size_t fill_up_remaining_space(HeapRegion* alloc_region,
122 bool bot_updates);
123
124 // After a region is allocated by alloc_new_region, this
125 // method is used to set it as the active alloc_region
126 void update_alloc_region(HeapRegion* alloc_region);
127
128 // Allocate a new active region and use it to perform a word_size
129 // allocation. The force parameter will be passed on to
130 // G1CollectedHeap::allocate_new_alloc_region() and tells it to try
131 // to allocate a new region even if the max has been reached.
132 HeapWord* new_alloc_region_and_allocate(size_t word_size, bool force);
133
134 void fill_in_ext_msg(ar_ext_msg* msg, const char* message);
135
136 protected:
137 // Retire the active allocating region. If fill_up is true then make
138 // sure that the region is full before we retire it so that no one
139 // else can allocate out of it.
140 // Returns the number of bytes that have been filled up during retire.
141 virtual size_t retire(bool fill_up);
142
143 // For convenience as subclasses use it.
144 static G1CollectedHeap* _g1h;
145
146 virtual HeapRegion* allocate_new_region(size_t word_size, bool force) = 0;
147 virtual void retire_region(HeapRegion* alloc_region,
148 size_t allocated_bytes) = 0;
149
150 G1AllocRegion(const char* name, bool bot_updates);
151
152 public:
153 static void setup(G1CollectedHeap* g1h, HeapRegion* dummy_region);
154
155 HeapRegion* get() const {
259 }
260 };
261
262 class SurvivorGCAllocRegion : public G1GCAllocRegion {
263 public:
264 SurvivorGCAllocRegion(G1EvacStats* stats)
265 : G1GCAllocRegion("Survivor GC Alloc Region", false /* bot_updates */, stats, InCSetState::Young) { }
266 };
267
268 class OldGCAllocRegion : public G1GCAllocRegion {
269 public:
270 OldGCAllocRegion(G1EvacStats* stats)
271 : G1GCAllocRegion("Old GC Alloc Region", true /* bot_updates */, stats, InCSetState::Old) { }
272
273 // This specialization of release() makes sure that the last card that has
274 // been allocated into has been completely filled by a dummy object. This
275 // avoids races when remembered set scanning wants to update the BOT of the
276 // last card in the retained old gc alloc region, and allocation threads
277 // allocating into that card at the same time.
278 virtual HeapRegion* release();
279 };
280
281 class ar_ext_msg : public err_msg {
282 public:
283 ar_ext_msg(G1AllocRegion* alloc_region, const char *message) : err_msg("%s", "") {
284 alloc_region->fill_in_ext_msg(this, message);
285 }
286 };
287
288 #endif // SHARE_VM_GC_G1_G1ALLOCREGION_HPP
|
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 */
24
25 #ifndef SHARE_VM_GC_G1_G1ALLOCREGION_HPP
26 #define SHARE_VM_GC_G1_G1ALLOCREGION_HPP
27
28 #include "gc/g1/heapRegion.hpp"
29 #include "gc/g1/g1EvacStats.hpp"
30 #include "gc/g1/g1InCSetState.hpp"
31
32 class G1CollectedHeap;
33
34 // 0 -> no tracing, 1 -> basic tracing, 2 -> basic + allocation tracing
35 #define G1_ALLOC_REGION_TRACING 0
36
37 // A class that holds a region that is active in satisfying allocation
38 // requests, potentially issued in parallel. When the active region is
39 // full it will be retired and replaced with a new one. The
40 // implementation assumes that fast-path allocations will be lock-free
41 // and a lock will need to be taken when the active region needs to be
42 // replaced.
43
44 class G1AllocRegion VALUE_OBJ_CLASS_SPEC {
45
46 private:
47 // The active allocating region we are currently allocating out
48 // of. The invariant is that if this object is initialized (i.e.,
49 // init() has been called and release() has not) then _alloc_region
50 // is either an active allocating region or the dummy region (i.e.,
51 // it can never be NULL) and this object can be used to satisfy
52 // allocation requests. If this object is not initialized
53 // (i.e. init() has not been called or release() has been called)
54 // then _alloc_region is NULL and this object should not be used to
55 // satisfy allocation requests (it was done this way to force the
56 // correct use of init() and release()).
57 HeapRegion* volatile _alloc_region;
58
59 // Allocation context associated with this alloc region.
60 AllocationContext_t _allocation_context;
61
62 // It keeps track of the distinct number of regions that are used
63 // for allocation in the active interval of this object, i.e.,
64 // between a call to init() and a call to release(). The count
111 size_t* actual_word_size,
112 bool bot_updates);
113
114 // Ensure that the region passed as a parameter has been filled up
115 // so that noone else can allocate out of it any more.
116 // Returns the number of bytes that have been wasted by filled up
117 // the space.
118 static size_t fill_up_remaining_space(HeapRegion* alloc_region,
119 bool bot_updates);
120
121 // After a region is allocated by alloc_new_region, this
122 // method is used to set it as the active alloc_region
123 void update_alloc_region(HeapRegion* alloc_region);
124
125 // Allocate a new active region and use it to perform a word_size
126 // allocation. The force parameter will be passed on to
127 // G1CollectedHeap::allocate_new_alloc_region() and tells it to try
128 // to allocate a new region even if the max has been reached.
129 HeapWord* new_alloc_region_and_allocate(size_t word_size, bool force);
130
131 protected:
132 // Retire the active allocating region. If fill_up is true then make
133 // sure that the region is full before we retire it so that no one
134 // else can allocate out of it.
135 // Returns the number of bytes that have been filled up during retire.
136 virtual size_t retire(bool fill_up);
137
138 // For convenience as subclasses use it.
139 static G1CollectedHeap* _g1h;
140
141 virtual HeapRegion* allocate_new_region(size_t word_size, bool force) = 0;
142 virtual void retire_region(HeapRegion* alloc_region,
143 size_t allocated_bytes) = 0;
144
145 G1AllocRegion(const char* name, bool bot_updates);
146
147 public:
148 static void setup(G1CollectedHeap* g1h, HeapRegion* dummy_region);
149
150 HeapRegion* get() const {
254 }
255 };
256
257 class SurvivorGCAllocRegion : public G1GCAllocRegion {
258 public:
259 SurvivorGCAllocRegion(G1EvacStats* stats)
260 : G1GCAllocRegion("Survivor GC Alloc Region", false /* bot_updates */, stats, InCSetState::Young) { }
261 };
262
263 class OldGCAllocRegion : public G1GCAllocRegion {
264 public:
265 OldGCAllocRegion(G1EvacStats* stats)
266 : G1GCAllocRegion("Old GC Alloc Region", true /* bot_updates */, stats, InCSetState::Old) { }
267
268 // This specialization of release() makes sure that the last card that has
269 // been allocated into has been completely filled by a dummy object. This
270 // avoids races when remembered set scanning wants to update the BOT of the
271 // last card in the retained old gc alloc region, and allocation threads
272 // allocating into that card at the same time.
273 virtual HeapRegion* release();
274 };
275
276 #endif // SHARE_VM_GC_G1_G1ALLOCREGION_HPP
|