Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17).
Reviewed-by: kvn, coleenp, jmasa
Fixes a race on the dirty card queue completed buffer list between worker thread(s) performing a flush of a deferred store barrier (enqueueing a newly completed buffer) and worker thread(s) in the RSet updating code claiming completed buffers. Removed the routine that removes elements from the completed update buffer queue using a CAS.
Reviewed-by: ysr, tonyp
ScavengeALot now causes an incremental (but possibly partially young, in the G1 sense) collection. Some such collections may be abandoned on account of MMU specs. Band-aided a native leak associated with abandoned pauses, as well as an MMU tracker overflow related to frequent scavenge events in the face of a large MMU denominator interval; the latter is protected by a product flag that defaults to false.
Reviewed-by: tonyp
Protected stats dump with a new develop flag; other than for the dump, reconciled product and non-product behaviour in face of the error.
Reviewed-by: tonyp
Added instrumentation and (temporary) assert in non-product mode; clipped the value when found out-of-bounds in product mode. Fix of original issue will follow collection of data from this instrumentation.
Reviewed-by: jcoomes, tonyp
The type in the NEW_C_HEAP_ARRRY and FREE_C_HEAP_ARRAY calls in the buffer allocation code was changed from void* to char as the size argument had already been mulitipled by the byte size of an object pointer.
Reviewed-by: ysr, tonyp
Allow iteration over the shared spaces when using CDS, repealing previous proscription. Deferred further required CDS-related cleanups of perm gen to CR 6897789.
Reviewed-by: phh, jmasa
Incorrect code was being generated for the store operation in the null case of the aastore bytecode template. The bad code was generated by the store_heap_oop routine which takes a Register as its second argument. Passing NULL_WORD (0) as the second argument causes the value to be converted to Register(0), which is rax. Thus the generated store was "mov (dst), $rax" instead of "mov (dst), $0x0". Changed calls to store_heap_oop that pass NULL_WORD as the second argument to a new routine store_heap_oop_null.
Reviewed-by: kvn, twisti
Restore old behaviour wrt HeapDumpPath; first dump goes to <file>, <n>th dump goes to <file>.<n-1>, with default value of <file> the same as before.
Reviewed-by: alanb, jcoomes, tonyp
The fix addresses two memory leaks in G1 code: (1) _evac_failure_scan_stack - a resource object allocated on the C heap was not freed; (2) RSHashTable were linked into deleted list which was only cleared at full GC.
Reviewed-by: tonyp, iveresov
6889757: G1: enable card mark elision for initializing writes from compiled code (ReduceInitialCardMarks)
Defer the (compiler-elided) card-mark upon a slow-path allocation until after the store and before the next subsequent safepoint; G1 now answers yes to can_elide_tlab_write_barriers().
Reviewed-by: jcoomes, kvn, never
