harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Salikh Zakirov <Salikh.Zaki...@Intel.com>
Subject Re: [drlvm][gc/threading] need the two lsb's from object header for MMTk port
Date Mon, 09 Oct 2006 10:04:07 GMT
Weldon Washburn wrote:
> Artem,
> I'd like to confirm what you said. For GC_BIT_MASK, it looks like the
> bottom
> two bits of byte number one is available for exclusive GC use.  If the GC
> needs to alter these two bits while the mutator(s) are running, the GC
> needs
> to use CAS on the entire 32 bits of obj_info.  Does this sound right?

Doing 32-bit CAS while mutators are running looks like a safe solution.
However, it can degrade performance considerably.

Can we instead consider locking the object monitor before modifying its
header bits?

Terms of use : http://incubator.apache.org/harmony/mailing.html
To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
For additional commands, e-mail: harmony-dev-help@incubator.apache.org

View raw message