RFR(S/M): 7132678: G1: verify that the marking bitmaps have no marks for objects over TAMS

[Srinivas Ramakrishna]

Never mind, didn't read yr email closely. Perhaps check_bitmaps() shouldn't be PRODUCT_RETURN? Yr point well-taken...

ysr1729

On May 15, 2013, at 17:40, Srinivas Ramakrishna <ysr1729 at gmail.com> wrote:

> Jon, 
> 
> That's to support heap verification in product builds -- via a diagnostic option.
> 
> -- Ramki
> 
> ysr1729
> 
> On May 15, 2013, at 15:11, Jon Masamitsu <jon.masamitsu at oracle.com> wrote:
> 
>> John,
>> 
>> Why use guarantee() here instead of a  assert()?
>> 
>> http://cr.openjdk.java.net/~johnc/7132678/webrev.0/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp.frames.html
>> 
>> 5945 void G1CollectedHeap::check_bitmaps(const char* caller, HeapRegion* hr) {
>> 5946   if (!G1VerifyBitmaps) return;
>> 5947
>> 5948   guarantee(verify_bitmaps(caller, hr), "bitmap verification");
>> 5949 }
>> 
>> check_bitmap() has a PRODUCT_RETURN.  Is this so it works in an optimized build?
>> 
>> Jon
>> 
>> On 1/15/2013 12:10 PM, John Cuthbertson wrote:
>>> Hi Everyone,
>>> 
>>> Can I have a couple of volunteers review the changes for this CR? The webrev can be found at: http://cr.openjdk.java.net/~johnc/7132678/webrev.0/
>>> 
>>> Most of the changes come from a patch that Tony gave me before he left and I had to tweak them slightly to remove a spurious failure. The changes verify that the heap regions don't have any marks between [TAMS, top) at strategic places: start and end of each GC, start and end of remark and cleanup, and when allocating a region. Tony deserves the bulk of the credit so, if possible and there are no objections, I intend to list him as author of the change and include myself as a reviewer.
>>> 
>>> Testing:
>>> GC test suite with the both the new flags (separately and together) and a low IHOP value.
>>> jprt with the new flags (+IgnoreUnrecognizedVMOptions so that product test runs did not fail).
>>> 
>>> Thanks,
>>> 
>>> JohnC
>>