Right, but for my case i know before that the line i
am going to invalidate is in shared state. So, to
force a write miss is it possible to do an
invalidation first (without regard of mesi, from the
processor itself) and then issue the write request?

which function can i use for this? i need something
which can do this thing internally without actually
generating any write request.



--- Steve Reinhardt <[EMAIL PROTECTED]> escribió:

> On Nov 20, 2007 6:49 AM, abc def
> <[EMAIL PROTECTED]> wrote:
> > Suppose in my simulation i have L1 cache and no
> L2.
> > Now i want some request to access cache but some
> > should be forced to go to network as if there is
> no
> > L1.
> > How to do this efficiently?
> 
> If you have a distinct set of uncacheable addresses,
> then you can just
> set the UNCACHEABLE bit in the flags field of the
> Request object.
> 
> If you want to bypass the L1 sometimes (and
> sometimes not) for the
> same address, then this won't work, as you might
> bypass the L1 when
> that's where the only up-to-date copy is.
> 
> >
> > In cpu.cc there is a boolean variable called
> do_access
> > which is stated to control cache access. But in
> the
> > code there is nothing mentioned what happens
> do_access
> > is false:
> >
> > /*
> > if (do_access) {
> >             if
> (!dcachePort.sendTiming(dcache_pkt)) {
> >                 _status = DcacheRetry;
> >             } else {
> >                 _status = DcacheWaitResponse;
> >                 // memory system takes ownership
> of packet
> >                 dcache_pkt = NULL;
> >             }
> >         }
> > */
> 
> When do_access is false, the access is not
> performed.  If you look a
> little more carefully at how that flag is used,
> you'll see that it
> only gets set when there's a store-conditional that
> is guaranteed to
> fail so there's no point in even going to the cache
> with it.
> 
> Steve
> _______________________________________________
> m5-users mailing list
> m5-users@m5sim.org
> http://m5sim.org/cgi-bin/mailman/listinfo/m5-users
> 



       
______________________________________________ 
¿Chef por primera vez?
Sé un mejor Cocinillas. 
http://es.answers.yahoo.com/info/welcome
_______________________________________________
m5-users mailing list
m5-users@m5sim.org
http://m5sim.org/cgi-bin/mailman/listinfo/m5-users

Reply via email to