Thu, 26 Jun 2014 11:36:58 +0200
8047818: G1 HeapRegions can no longer be ContiguousSpaces
Summary: Change parent of G1OffsetTableContigSpace to CompactibleSpace, reimplement missing functionality
Reviewed-by: stefank, jmasa, tschatzl
1 /*
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25 #ifndef SHARE_VM_MEMORY_THREADLOCALALLOCBUFFER_INLINE_HPP
26 #define SHARE_VM_MEMORY_THREADLOCALALLOCBUFFER_INLINE_HPP
28 #include "gc_interface/collectedHeap.hpp"
29 #include "memory/threadLocalAllocBuffer.hpp"
30 #include "runtime/atomic.hpp"
31 #include "runtime/thread.hpp"
32 #include "utilities/copy.hpp"
34 inline HeapWord* ThreadLocalAllocBuffer::allocate(size_t size) {
35 invariants();
36 HeapWord* obj = top();
37 if (pointer_delta(end(), obj) >= size) {
38 // successful thread-local allocation
39 #ifdef ASSERT
40 // Skip mangling the space corresponding to the object header to
41 // ensure that the returned space is not considered parsable by
42 // any concurrent GC thread.
43 size_t hdr_size = oopDesc::header_size();
44 Copy::fill_to_words(obj + hdr_size, size - hdr_size, badHeapWordVal);
45 #endif // ASSERT
46 // This addition is safe because we know that top is
47 // at least size below end, so the add can't wrap.
48 set_top(obj + size);
50 invariants();
51 return obj;
52 }
53 return NULL;
54 }
56 inline size_t ThreadLocalAllocBuffer::compute_size(size_t obj_size) {
57 const size_t aligned_obj_size = align_object_size(obj_size);
59 // Compute the size for the new TLAB.
60 // The "last" tlab may be smaller to reduce fragmentation.
61 // unsafe_max_tlab_alloc is just a hint.
62 const size_t available_size = Universe::heap()->unsafe_max_tlab_alloc(myThread()) /
63 HeapWordSize;
64 size_t new_tlab_size = MIN2(available_size, desired_size() + aligned_obj_size);
66 // Make sure there's enough room for object and filler int[].
67 const size_t obj_plus_filler_size = aligned_obj_size + alignment_reserve();
68 if (new_tlab_size < obj_plus_filler_size) {
69 // If there isn't enough room for the allocation, return failure.
70 if (PrintTLAB && Verbose) {
71 gclog_or_tty->print_cr("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ")"
72 " returns failure",
73 obj_size);
74 }
75 return 0;
76 }
77 if (PrintTLAB && Verbose) {
78 gclog_or_tty->print_cr("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ")"
79 " returns " SIZE_FORMAT,
80 obj_size, new_tlab_size);
81 }
82 return new_tlab_size;
83 }
86 void ThreadLocalAllocBuffer::record_slow_allocation(size_t obj_size) {
87 // Raise size required to bypass TLAB next time. Why? Else there's
88 // a risk that a thread that repeatedly allocates objects of one
89 // size will get stuck on this slow path.
91 set_refill_waste_limit(refill_waste_limit() + refill_waste_limit_increment());
93 _slow_allocations++;
95 if (PrintTLAB && Verbose) {
96 Thread* thrd = myThread();
97 gclog_or_tty->print("TLAB: %s thread: "INTPTR_FORMAT" [id: %2d]"
98 " obj: "SIZE_FORMAT
99 " free: "SIZE_FORMAT
100 " waste: "SIZE_FORMAT"\n",
101 "slow", p2i(thrd), thrd->osthread()->thread_id(),
102 obj_size, free(), refill_waste_limit());
103 }
104 }
106 #endif // SHARE_VM_MEMORY_THREADLOCALALLOCBUFFER_INLINE_HPP