Tue, 18 Sep 2012 23:35:42 -0700
7045397: NPG: Add freelists to class loader arenas.
Reviewed-by: coleenp, stefank, jprovino, ohair
1 /*
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25 #include "precompiled.hpp"
26 #include "gc_implementation/concurrentMarkSweep/freeChunk.hpp"
27 #include "memory/freeBlockDictionary.hpp"
28 #include "utilities/copy.hpp"
30 #ifndef PRODUCT
32 #define baadbabeHeapWord badHeapWordVal
33 #define deadbeefHeapWord 0xdeadbeef
35 size_t const FreeChunk::header_size() {
36 return sizeof(FreeChunk)/HeapWordSize;
37 }
39 void FreeChunk::mangleAllocated(size_t size) {
40 // mangle all but the header of a just-allocated block
41 // of storage
42 assert(size >= MinChunkSize, "smallest size of object");
43 // we can't assert that _size == size because this may be an
44 // allocation out of a linear allocation block
45 assert(sizeof(FreeChunk) % HeapWordSize == 0,
46 "shouldn't write beyond chunk");
47 HeapWord* addr = (HeapWord*)this;
48 size_t hdr = header_size();
49 Copy::fill_to_words(addr + hdr, size - hdr, baadbabeHeapWord);
50 }
52 void FreeChunk::mangleFreed(size_t sz) {
53 assert(baadbabeHeapWord != deadbeefHeapWord, "Need distinct patterns");
54 // mangle all but the header of a just-freed block of storage
55 // just prior to passing it to the storage dictionary
56 assert(sz >= MinChunkSize, "smallest size of object");
57 assert(sz == size(), "just checking");
58 HeapWord* addr = (HeapWord*)this;
59 size_t hdr = header_size();
60 Copy::fill_to_words(addr + hdr, sz - hdr, deadbeefHeapWord);
61 }
63 void FreeChunk::verifyList() const {
64 FreeChunk* nextFC = next();
65 if (nextFC != NULL) {
66 assert(this == nextFC->prev(), "broken chain");
67 assert(size() == nextFC->size(), "wrong size");
68 nextFC->verifyList();
69 }
70 }
71 #endif
73 void FreeChunk::print_on(outputStream* st) {
74 st->print_cr("Next: " PTR_FORMAT " Prev: " PTR_FORMAT " %s",
75 next(), prev(), cantCoalesce() ? "[can't coalesce]" : "");
76 }