Re: [Qemu-devel] [Qemu-ppc] [PATCH 03/77] ppc: Do some batching of TCG tlb flushes

[Benjamin Herrenschmidt]

On Mon, 2015-11-16 at 16:00 +1100, David Gibson wrote:
> 
> >  //#define DEBUG_MMU
> >  //#define DEBUG_BATS
> > @@ -1940,6 +1941,7 @@ void ppc_tlb_invalidate_all(CPUPPCState *env)
> >      case POWERPC_MMU_2_03:
> >      case POWERPC_MMU_2_06:
> >      case POWERPC_MMU_2_07:
> > +        env->tlb_need_flush = 0;
> >  #endif /* defined(TARGET_PPC64) */
> >          tlb_flush(CPU(cpu), 1);
> >          break;
> 
> Any particular reason you're leaving this one as an immediate rather
> than deferred flush?

A couple yes. It's mostly unused on server CPUs (we don't do tlbia),
and it's used by ppc_cpu_reset(). In that latter case, I like having
everything really cleaned up ... 

> Should you be clearing the pending flush flag cpu_reset()?

That should happen as a result of the above.

Cheers,
Ben.