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8237645: Remove OopsInGenClosure::par_do_barrier

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Reviewed-by: sjohanss
This commit is contained in:
Stefan Karlsson 2020-01-24 09:24:46 +01:00
parent 17106c9e9d
commit b223907794
4 changed files with 0 additions and 53 deletions
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34
src/hotspot/share/gc/shared/cardTableRS.cpp
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@ -244,40 +244,6 @@ void ClearNoncleanCardWrapper::do_MemRegion(MemRegion mr) {
}
}
// clean (by dirty->clean before) ==> cur_younger_gen
// dirty ==> cur_youngergen_and_prev_nonclean_card
// precleaned ==> cur_youngergen_and_prev_nonclean_card
// prev-younger-gen ==> cur_youngergen_and_prev_nonclean_card
// cur-younger-gen ==> cur_younger_gen
// cur_youngergen_and_prev_nonclean_card ==> no change.
void CardTableRS::write_ref_field_gc_par(void* field, oop new_val) {
volatile CardValue* entry = byte_for(field);
do {
CardValue entry_val = *entry;
// We put this first because it's probably the most common case.
if (entry_val == clean_card_val()) {
// No threat of contention with cleaning threads.
*entry = cur_youngergen_card_val();
return;
} else if (card_is_dirty_wrt_gen_iter(entry_val)
|| is_prev_youngergen_card_val(entry_val)) {
// Mark it as both cur and prev youngergen; card cleaning thread will
// eventually remove the previous stuff.
CardValue new_val = cur_youngergen_and_prev_nonclean_card;
CardValue res = Atomic::cmpxchg(entry, entry_val, new_val);
// Did the CAS succeed?
if (res == entry_val) return;
// Otherwise, retry, to see the new value.
continue;
} else {
assert(entry_val == cur_youngergen_and_prev_nonclean_card
|| entry_val == cur_youngergen_card_val(),
"should be only possibilities.");
return;
}
} while (true);
}
void CardTableRS::younger_refs_in_space_iterate(Space* sp,
OopsInGenClosure* cl,
uint n_threads) {

5
src/hotspot/share/gc/shared/cardTableRS.hpp
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@ -124,11 +124,6 @@ public:
inline_write_ref_field_gc(field, new_val);
}
// Override. Might want to devirtualize this in the same fashion as
// above. Ensures that the value of the card for field says that it's
// a younger card in the current collection.
virtual void write_ref_field_gc_par(void* field, oop new_val);
bool is_aligned(HeapWord* addr) {
return is_card_aligned(addr);
}

3
src/hotspot/share/gc/shared/genOopClosures.hpp
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@ -57,9 +57,6 @@ class OopsInGenClosure : public OopIterateClosure {
// pointers must call the method below.
template <class T> void do_barrier(T* p);
// Version for use by closures that may be called in parallel code.
template <class T> void par_do_barrier(T* p);
public:
OopsInGenClosure() : OopIterateClosure(NULL),
_orig_gen(NULL), _gen(NULL), _gen_boundary(NULL), _rs(NULL) {};

11
src/hotspot/share/gc/shared/genOopClosures.inline.hpp
View File

@ -62,17 +62,6 @@ template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
}
}
template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
assert(generation()->is_in_reserved(p), "expected ref in generation");
T heap_oop = RawAccess<>::oop_load(p);
assert(!CompressedOops::is_null(heap_oop), "expected non-null oop");
oop obj = CompressedOops::decode_not_null(heap_oop);
// If p points to a younger generation, mark the card.
if ((HeapWord*)obj < gen_boundary()) {
rs()->write_ref_field_gc_par(p, obj);
}
}
inline BasicOopsInGenClosure::BasicOopsInGenClosure(Generation* gen) : OopsInGenClosure(gen) {
}