Re: Patch: 32bit and 64bit Sparc Linux support in libffi

[Bryce McKinlay <bryce at albatross dot co dot nz>]

Jeff Sturm wrote:

> Bryce McKinlay wrote:
> > Cool. libgcj still won't run on linux/sparc, though, as the current gc
> > doesn't have a GC_Test_and_set() implementation for sparc.
>
> hmm... we really should have GC_test_and_set for linux/sparc.  The
> pthreads fallback is a nice idea, albeit at degraded performance.

Yeah. I'm planning to try building it without the spinlocks to see if they
are the source of GCTest failures on my SMP (x86) machine. Linuxthreads
uses "LOCK, CMPXCHGL" while gc uses XCHG with no "LOCK". I'm wondering if
this is actually SMP-safe?

> Sparc has an atomic swap instruction, similar to x86 XCHG.  It would be
> trivial to add, but I don't have a test machine (all my sparc hardware
> runs Solaris).  If I write one can someone else test it on Linux?

I should be able to test it if no-one else volunteers.

regards

  [ bryce ]