On Mon, Jan 28, 2019 at 10:46:13AM +0100, Cédric Le Goater wrote: > From: Benjamin Herrenschmidt <b...@kernel.crashing.org> > > There's no point in going out of translation on an SMT OR with > mttcg since the backend won't do anything useful such as pausing, > it's only useful on traditional TCG to give time to other > processors.
Is it actively harmful in the MTTCG case, or just pointless?
>
> Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
> Signed-off-by: Cédric Le Goater <c...@kaod.org>
> ---
> target/ppc/translate.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/target/ppc/translate.c b/target/ppc/translate.c
> index e169c43643a1..7d40a1fbe6bd 100644
> --- a/target/ppc/translate.c
> +++ b/target/ppc/translate.c
> @@ -1580,7 +1580,7 @@ static void gen_pause(DisasContext *ctx)
> tcg_temp_free_i32(t0);
>
> /* Stop translation, this gives other CPUs a chance to run */
> - gen_exception_nip(ctx, EXCP_HLT, ctx->base.pc_next);
> + gen_exception_nip(ctx, EXCP_INTERRUPT, ctx->base.pc_next);
I don't see how this change relates to the rest.
> }
> #endif /* defined(TARGET_PPC64) */
>
> @@ -1662,7 +1662,9 @@ static void gen_or(DisasContext *ctx)
> * than no-op, e.g., miso(rs=26), yield(27), mdoio(29), mdoom(30),
> * and all currently undefined.
> */
> - gen_pause(ctx);
> + if (!mttcg_enabled) {
> + gen_pause(ctx);
> + }
> #endif
> #endif
> }
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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