Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes

Reviewed-by: kvn

Summary: Disable reference discovery and processing during concurrent marking by disabling fix for 6994628.
Reviewed-by: tonyp, ysr

Summary: Repurpose the existing flag G1PrintRegionLivenessInfo to print out the liveness distribution across the regions in the heap at the end of marking.
Reviewed-by: iveresov, jwilhelm

Summary: The epochs on the card cache array are initialized to 0 and our initial epoch also starts at 0. So, until the first GC, it might be possible to successfully "claim" a card which was in fact never initialized.
Reviewed-by: johnc, iveresov, ysr

7023151: G1: refactor the code that operates on _cur_alloc_region to be re-used for allocs by the GC threads
7018286: G1: humongous allocation attempts should take the GC locker into account
Summary: First, this change replaces the asymmetric locking scheme in the G1 slow alloc path by a summetric one. Second, it factors out the code that operates on _cur_alloc_region so that it can be re-used for allocations by the GC threads in the future.
Reviewed-by: stefank, brutisso, johnc

Summary: What the synopsis says.
Reviewed-by: jwilhelm, iveresov, johnc

Summary: Manage allocation/freeing of the card cache counts and epochs arrays directly so that an allocation failure while attempting to expand these arrays does not abort the JVM. Failure to expand these arrays is not fatal.
Reviewed-by: iveresov, tonyp

Summary: Changed default value of WorkStealingYieldsBeforeSleep from 1000 to 5000. Added more information to G1 pause logging.
Reviewed-by: jwilhelm, tonyp, jmasa

7029036: Card-table verification hangs with all framework collectors, except G1, even before the first GC
Summary: When verifying clean card ranges, use memory-range-bounded iteration over oops of objects overlapping that range, thus avoiding the otherwise quadratic worst-case cost of scanning large object arrays.
Reviewed-by: jmasa, jwilhelm, tonyp

Summary: Filter ref-containing locations through the memory-interval specified in the call.
Reviewed-by: jcoomes, jwilhelm, tonyp

Reviewed-by: iveresov, jcoomes, dcubed

Summary: Removed
Reviewed-by: ohair, coleenp

Reviewed-by: never, coleenp, ysr, jwilhelm

Summary: only clear the interrupt state if we will report that it was set
Reviewed-by: dcubed, alanb, phh, coleenp, dice

Reviewed-by: never, phh, stefank, kamg, dholmes, coleenp

Reviewed-by: kvn

Summary: Add predicates when loop head bytecode is parsed instead of when back branch bytecode is parsed.
Reviewed-by: never

Reviewed-by: kvn, never

Reviewed-by: kvn, coleenp, twisti, stefank

Reviewed-by: kvn

7011865: JSR 292 CTW fails: !THREAD->is_Compiler_thread() failed: Can not load classes with the Compiler thre
Reviewed-by: kvn, never

Summary: This new default has shown improvement across many workloads.
Reviewed-by: kvn
Contributed-by: tom.deneau@amd.com

Summary: Use _max_num_q = max(discovery_degree, processing_degree), and let balance_queues() redistribute from discovery_degree to processing_degree of queues. This should also allow a more dynamic and flexible parallelism policy in the future.
Reviewed-by: jmasa, johnc

Summary: And out lsb which is set for symbols in constant pool slots to distinguish them from strings
Reviewed-by: phh, dholmes, never, dcubed

6627787: CMS: JVM refuses to start up with -Xms16m -Xmx16m
7000125: CMS: Anti-monotone young gen sizing with respect to maximum whole heap size specification
7027529: CMS: retire CMSUseOldDefaults flag
Summary: Simplify CMS heap sizing code, relying on ergonomic initial sizing consistent with other collectors for the most part, controlling only young gen sizing to rein in pause times. Make CMS young gen sizing default statically cpu-dependant. Remove inconsistencies wrt generation sizing and policy code, allowing for the fixing for 6627787 and 7000125. For 7027529, retire the flag CMSUseOldDefaults which had been introduced as a bridge from JDK 5 to JDK 6 a number of years ago.
Reviewed-by: brutisso, poonam

7024970: 2/3 assert(ServiceThread::is_service_thread(Thread::current())) failed: Service thread must post enqueue
Summary: Change nmethod_lock() to also prevent zombification of the nmethod. CompiledMethodUnload events also need to lock the nmethod. Clean ups in nmethod::make_not_entrant_or_zombie()
Reviewed-by: dholmes, kamg, never, dsamersoff, ysr, coleenp, acorn

Summary: Move initialization of the '_instance' field to avoid race with ServiceThread start.
Reviewed-by: dholmes, kamg, never, dsamersoff, ysr, coleenp, acorn

Summary: Count enable_icms() and disable_icms() events so as to prevent inteference between concurrent calls, which can cause the iCMS thread to be left stranded in icms_wait() with an unserviced request and no young allocations to unwedge it.
Reviewed-by: jcoomes, poonam

Summary: package and class renaming only; delete unused methods and classes
Reviewed-by: twisti

Summary: consolidate runtime support in java.dyn.MethodHandleNatives; include transitional compatibility logic
Reviewed-by: twisti

Summary: Remove _last_pc_desc and use pcdescs[0] instead.
Reviewed-by: dcubed, coleenp, ysr

Summary: add missing check this->dual() != TypeAryPtr::OOPS into TypeAryPtr::klass().
Reviewed-by: never

Summary: Check that -XX:ParGCArrayScanChunk has a value larger than zero.
Reviewed-by: johnc, jmasa, ysr

Summary: incorrect handling of c2i deoptimization on little endian architectures
Reviewed-by: never

Summary: removed an ifdef IA32 around harmless code useful for some ports
Reviewed-by: chrisphi, never

Summary: Use largest_free_block() instead of unallocated_capacity().
Reviewed-by: iveresov, never, ysr

Summary: Put symbol printing under Verbose and WizardMode so you can get this information if you really want it.
Reviewed-by: phh, stefank, never, dholmes, jcoomes

6965570: assert(!needs_patching && x->is_loaded(),"how do we know it's volatile if it's not loaded")
Reviewed-by: iveresov

Summary: arrays pointers meet must fall to bottom if exact array klasses in upper lattice are not equal or super klass is exact.
Reviewed-by: never