RFR: 8057536: Refactor G1 to allow context specific allocations

[Mikael Gerdin]

Hi Stefan,

On Thursday 04 September 2014 14.45.30 Stefan Johansson wrote:
> Hi,
> 
> Please review these changes for:
> https://bugs.openjdk.java.net/browse/JDK-8057536
> 
> Webrev:
> http://cr.openjdk.java.net/~sjohanss/8057536/webrev.00/

g1Allocator.hpp:

reuse_retaind_... => reuse_retained_...

G1ParGCAllocator::allocate does not have the SurvivorAlignmentInBytes change 
when it was broken out from G1ParScanThreadState.

g1Allocator.cpp:

reuse_retaind_... => reuse_retained_...
two spaces after return type of retire_alloc_buffers
align parameters to flush_stats_and_retire

g1CollectedHeap.hpp:

align the parameters to "attempt_allocation_at_safepoint", 
"survivor_attempt_allocation", "old_attempt_allocation"

g1CollectedHeap.cpp:

You didn't move the methods of Mutator/SurvivorGC/OldGC alloc region to 
g1Allocator.cpp

align the parameters at the call to "attempt_allocation"
align the parameters to "attempt_allocation_at_safepoint"

g1CollectedHeap.inline.hpp:

align the parameters at the call to "attempt_allocation"

align the parameters to "survivor_attempt_allocation", 
"old_attempt_allocation"

heapRegion.cpp:

HeapRegion::print_on is designed to produce short output. Can you shorten the 
output? Either by disabling the printout if contexts aren't used or disable it 
for context-0 regions. Or have a format like "C%4u".

For most of the style changes I'm ok with a follow-up change to address them. 
The rest of the change looks ok to me.

I'm not a 8u Reviewer.

/Mikael

> 
> Summary:
> These changes are made to allow G1 to do context specific allocation. As
> part of this a G1Allocator class has be refactored out of
> G1CollectedHeap which can be extended to implement the specific context
> code. Currently only the G1DefaultAllocator is implemented, this
> allocator only makes use of one context to have the same behavior as
> prior to this enhancement.
> 
> Testing:
> * JPRT
> * Manual verification
> * Local ute runs of vm.quick.testlist
> 
> Thanks,
> Stefan