Am 02.03.2015 um 17:43 schrieb Michael Mueller: > On Mon, 02 Mar 2015 14:57:21 +0100 > Andreas Färber <afaerber@xxxxxxx> wrote: > >>> int configure_accelerator(MachineState *ms) >>> { >>> - const char *p; >>> + const char *p, *name; >>> char buf[10]; >>> int ret; >>> bool accel_initialised = false; >>> bool init_failed = false; >>> AccelClass *acc = NULL; >>> + ObjectClass *oc; >>> + bool probe_mode = false; >>> >>> p = qemu_opt_get(qemu_get_machine_opts(), "accel"); >>> if (p == NULL) { >>> - /* Use the default "accelerator", tcg */ >>> - p = "tcg"; >>> + oc = (ObjectClass *) MACHINE_GET_CLASS(current_machine); >>> + name = object_class_get_name(oc); >>> + probe_mode = !strcmp(name, "none" TYPE_MACHINE_SUFFIX); >>> + if (probe_mode) { >>> + /* Use these accelerators in probe mode, tcg should be last */ >>> + p = probe_mode_accels; >>> + } else { >>> + /* Use the default "accelerator", tcg */ >>> + p = "tcg"; >>> + } >>> } >> >> Can't we instead use an explicit ,accel=probe or ,accel=auto? >> That would then obsolete the next patch. > > How would you express the following with the accel=<pseudo-accel> approach? > > -probe -machine s390-ccw,accel=kvm > > Using machine "none" as default with tcg as last accelerator initialized should not break > anything. > > -M none Let me ask differently: What does -machine none or -M none have to do with probing? It reads as if you are introducing two probe modes. Why do you need both? If we have -probe, isn't that independent of which machine we specify? Who is going to call either, with which respective goal? I think that changing the semantics of an absent ,accel=foo parameter to mean something else than its longtime default of tcg is a bad idea. Have you testing qtest with it? Doesn't -qtest imply accel=qtest or is that always passed explicitly? Regards, Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Jennifer Guild, Dilip Upmanyu, Graham Norton; HRB 21284 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html