RFR (M): 8029396: PPC64 (part 212): Several memory ordering fixes in C-code.
vladimir.kozlov at oracle.com
Tue Dec 3 10:46:49 PST 2013
He may be not on runtime list.
On 12/3/13 10:15 AM, Coleen Phillimore wrote:
> Hi Goetz,
> I did look at this yesterday. It looks fine. I was trying to find if
> there were others that might have been missed. How did you find this
> set in this changeset? Did you look for volatile and find instances
> that didn't use CAS or other memory ordering instructions? We've done
> this exercise before but it's easy to miss things.
> On 12/03/2013 12:09 PM, Lindenmaier, Goetz wrote:
>> could somebody of rt and gc please have a look at the following change?
>> It contains memory ordering fixes as required by the PPC64 port, see also
>> Thanks and best regards,
>> -----Original Message-----
>> From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com]
>> Sent: Montag, 2. Dezember 2013 22:42
>> To: Lindenmaier, Goetz; 'hotspot-dev at openjdk.java.net';
>> 'ppc-aix-port-dev at openjdk.java.net'
>> Subject: Re: RFR (M): 8029396: PPC64 (part 212): Several memory
>> ordering fixes in C-code.
>> These changes need to be reviewed by GC and Runtime group. Especially
>> first 2 changes (CMS).
>> The rest 6 changes are less performance critical and, I think they are
>> On 12/2/13 8:51 AM, Lindenmaier, Goetz wrote:
>>> This change contains a row of fixes to the memory ordering in
>>> runtime, GC etc.
>>> These are:
>>> - Accessing arrays in CMS (compactibleFreeListSpace.cpp)
>>> - CMS: Do release when marking a card dirty. The release must only be
>>> done if GC is running. (several files)
>>> - Method counter initialization (method.hpp).
>>> - Order accessing f1/f2 in constant pool cache.
>>> - Release stores in OopMapCache constructor (instanceKLass.cpp).
>>> - BiasedLocking: Release setting object header to displaced mark.
>>> - Release state of nmethod sweeper (sweeper.cpp).
>>> - Do barriers when writing the thread state (thread.hpp).
>>> Please review and test this change.
>>> If requested, I can part this into smaller changes. But for now
>>> I wanted to put them all into one change as they all address the
>>> problems with the PPC memory model.
>>> Best regards,
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