--- a/hotspot/src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.cpp Mon Jul 07 10:12:40 2014 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.cpp Mon Jul 07 12:37:11 2014 +0200
@@ -30,52 +30,23 @@
PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
-G1CodeRootChunk::G1CodeRootChunk() : _top(NULL), _next(NULL), _prev(NULL), _free(NULL) {
+G1CodeRootChunk::G1CodeRootChunk() : _top(NULL), _next(NULL), _prev(NULL) {
_top = bottom();
}
void G1CodeRootChunk::reset() {
_next = _prev = NULL;
- _free = NULL;
_top = bottom();
}
void G1CodeRootChunk::nmethods_do(CodeBlobClosure* cl) {
- NmethodOrLink* cur = bottom();
+ nmethod** cur = bottom();
while (cur != _top) {
- if (is_nmethod(cur)) {
- cl->do_code_blob(cur->_nmethod);
- }
+ cl->do_code_blob(*cur);
cur++;
}
}
-bool G1CodeRootChunk::remove_lock_free(nmethod* method) {
- NmethodOrLink* cur = bottom();
-
- for (NmethodOrLink* cur = bottom(); cur != _top; cur++) {
- if (cur->_nmethod == method) {
- bool result = Atomic::cmpxchg_ptr(NULL, &cur->_nmethod, method) == method;
-
- if (!result) {
- // Someone else cleared out this entry.
- return false;
- }
-
- // The method was cleared. Time to link it into the free list.
- NmethodOrLink* prev_free;
- do {
- prev_free = (NmethodOrLink*)_free;
- cur->_link = prev_free;
- } while (Atomic::cmpxchg_ptr(cur, &_free, prev_free) != prev_free);
-
- return true;
- }
- }
-
- return false;
-}
-
G1CodeRootChunkManager::G1CodeRootChunkManager() : _free_list(), _num_chunks_handed_out(0) {
_free_list.initialize();
_free_list.set_size(G1CodeRootChunk::word_size());
@@ -169,43 +140,34 @@
void G1CodeRootSet::add(nmethod* method) {
if (!contains(method)) {
- // Find the first chunk thatisn't full.
- G1CodeRootChunk* cur = _list.head();
- while (cur != NULL) {
- if (!cur->is_full()) {
- break;
- }
- cur = cur->next();
- }
-
- // All chunks are full, get a new chunk.
- if (cur == NULL) {
- cur = new_chunk();
+ // Try to add the nmethod. If there is not enough space, get a new chunk.
+ if (_list.head() == NULL || _list.head()->is_full()) {
+ G1CodeRootChunk* cur = new_chunk();
_list.return_chunk_at_head(cur);
}
-
- // Add the nmethod.
- bool result = cur->add(method);
-
+ bool result = _list.head()->add(method);
guarantee(result, err_msg("Not able to add nmethod "PTR_FORMAT" to newly allocated chunk.", method));
-
_length++;
}
}
-void G1CodeRootSet::remove_lock_free(nmethod* method) {
+void G1CodeRootSet::remove(nmethod* method) {
G1CodeRootChunk* found = find(method);
if (found != NULL) {
- bool result = found->remove_lock_free(method);
- if (result) {
- Atomic::dec_ptr((volatile intptr_t*)&_length);
+ bool result = found->remove(method);
+ guarantee(result, err_msg("could not find nmethod "PTR_FORMAT" during removal although we previously found it", method));
+ // eventually free completely emptied chunk
+ if (found->is_empty()) {
+ _list.remove_chunk(found);
+ free(found);
}
+ _length--;
}
assert(!contains(method), err_msg(PTR_FORMAT" still contains nmethod "PTR_FORMAT, this, method));
}
nmethod* G1CodeRootSet::pop() {
- while (true) {
+ do {
G1CodeRootChunk* cur = _list.head();
if (cur == NULL) {
assert(_length == 0, "when there are no chunks, there should be no elements");
@@ -218,7 +180,7 @@
} else {
free(_list.get_chunk_at_head());
}
- }
+ } while (true);
}
G1CodeRootChunk* G1CodeRootSet::find(nmethod* method) {