[RFA] Use data cache for stack accesses

[Daniel Jacobowitz]

On Wed, Jul 08, 2009 at 09:46:40PM +0100, Pedro Alves wrote:
> On Wednesday 08 July 2009 21:08:00, Jacob Potter write:
> > --- a/gdb/thread.c
> > +++ b/gdb/thread.c
> > @@ -848,6 +848,9 @@ switch_to_thread (ptid_t ptid)
> > Â  Â if (ptid_equal (ptid, inferior_ptid))
> > Â  Â  Â return;
> > Â 
> > + Â if (ptid_get_pid (ptid) != ptid_get_pid (inferior_ptid))
> > + Â  Â dcache_invalidate (target_dcache);
> > +
> 
> I'm not sure this would be 100% multi-address space safe.
> 
> Do we not have places where we switch inferior_ptid temporarily
> before calling reading memory, with save_inferior_ptid, without
> going through the high level switch_to_thread ?
> 
> What if we do this within dcache itself, similarly
> to get_thread_regcache?  That would be probably in memory_xfer_partial.

Or could we store a dcache per-inferior?  Jacob's right - I thought
there was an 'inferior_data' to store arbitrary data per-inferior,
but there isn't.  I don't like baking knowledge into other modules
of GDB that they can extract the PID and use it to key per-inferior
data.

Or just add it to struct inferior?

-- 
Daniel Jacobowitz
CodeSourcery