On Fri, Oct 13, 2017 at 01:31:44PM +0200, Greg Kurz wrote: > The current code assumes that only the CPU core object holds a > reference on each individual CPU object, and happily frees their > allocated memory when the core is unrealized. This is dangerous > as some other code can legitimely keep a pointer to a CPU if it > calls object_ref(), but it would end up with a dangling pointer. > > Let's allocate all CPUs with object_new() and let QOM frees them > when their reference count reaches zero. This greatly simplify the > code as we don't have to fiddle with the instance size anymore. > > Signed-off-by: Greg Kurz <gr...@kaod.org>
So, I'm pretty sure my first drafts of the core stuff did things this waym and it got nacked, for QOM lifetime reasons that I never really understood. > --- > v2: - mention code simplification in changelog > - use PowerPCCPU * and Object * instead of void * > --- > hw/ppc/spapr.c | 11 +++-------- > hw/ppc/spapr_cpu_core.c | 19 +++++++------------ > include/hw/ppc/spapr_cpu_core.h | 2 +- > 3 files changed, 11 insertions(+), 21 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index fd9813bde82f..d9555a3677be 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -3153,12 +3153,10 @@ void spapr_core_release(DeviceState *dev) > > if (smc->pre_2_10_has_unused_icps) { > sPAPRCPUCore *sc = SPAPR_CPU_CORE(OBJECT(dev)); > - sPAPRCPUCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(OBJECT(cc)); > - size_t size = object_type_get_instance_size(scc->cpu_type); > int i; > > for (i = 0; i < cc->nr_threads; i++) { > - CPUState *cs = CPU(sc->threads + i * size); > + CPUState *cs = CPU(sc->threads[i]); > > pre_2_10_vmstate_register_dummy_icp(cs->cpu_index); > } > @@ -3204,7 +3202,7 @@ static void spapr_core_plug(HotplugHandler > *hotplug_dev, DeviceState *dev, > sPAPRMachineClass *smc = SPAPR_MACHINE_CLASS(mc); > sPAPRCPUCore *core = SPAPR_CPU_CORE(OBJECT(dev)); > CPUCore *cc = CPU_CORE(dev); > - CPUState *cs = CPU(core->threads); > + CPUState *cs = CPU(core->threads[0]); > sPAPRDRConnector *drc; > Error *local_err = NULL; > int smt = kvmppc_smt_threads(); > @@ -3249,15 +3247,12 @@ static void spapr_core_plug(HotplugHandler > *hotplug_dev, DeviceState *dev, > core_slot->cpu = OBJECT(dev); > > if (smc->pre_2_10_has_unused_icps) { > - sPAPRCPUCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(OBJECT(cc)); > - size_t size = object_type_get_instance_size(scc->cpu_type); > int i; > > for (i = 0; i < cc->nr_threads; i++) { > sPAPRCPUCore *sc = SPAPR_CPU_CORE(dev); > - void *obj = sc->threads + i * size; > > - cs = CPU(obj); > + cs = CPU(sc->threads[i]); > pre_2_10_vmstate_unregister_dummy_icp(cs->cpu_index); > } > } > diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c > index 3a4c17401226..588f9b45714a 100644 > --- a/hw/ppc/spapr_cpu_core.c > +++ b/hw/ppc/spapr_cpu_core.c > @@ -79,13 +79,11 @@ const char *spapr_get_cpu_core_type(const char *cpu_type) > static void spapr_cpu_core_unrealizefn(DeviceState *dev, Error **errp) > { > sPAPRCPUCore *sc = SPAPR_CPU_CORE(OBJECT(dev)); > - sPAPRCPUCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(OBJECT(dev)); > - size_t size = object_type_get_instance_size(scc->cpu_type); > CPUCore *cc = CPU_CORE(dev); > int i; > > for (i = 0; i < cc->nr_threads; i++) { > - void *obj = sc->threads + i * size; > + Object *obj = OBJECT(sc->threads[i]); > DeviceState *dev = DEVICE(obj); > CPUState *cs = CPU(dev); > PowerPCCPU *cpu = POWERPC_CPU(cs); > @@ -146,9 +144,8 @@ static void spapr_cpu_core_realize(DeviceState *dev, > Error **errp) > sPAPRCPUCore *sc = SPAPR_CPU_CORE(OBJECT(dev)); > sPAPRCPUCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(OBJECT(dev)); > CPUCore *cc = CPU_CORE(OBJECT(dev)); > - size_t size; > Error *local_err = NULL; > - void *obj; > + Object *obj; > int i, j; > > if (!spapr) { > @@ -156,18 +153,16 @@ static void spapr_cpu_core_realize(DeviceState *dev, > Error **errp) > return; > } > > - size = object_type_get_instance_size(scc->cpu_type); > - sc->threads = g_malloc0(size * cc->nr_threads); > + sc->threads = g_new(PowerPCCPU *, cc->nr_threads); > for (i = 0; i < cc->nr_threads; i++) { > char id[32]; > CPUState *cs; > PowerPCCPU *cpu; > > - obj = sc->threads + i * size; > + obj = object_new(scc->cpu_type); > > - object_initialize(obj, size, scc->cpu_type); > cs = CPU(obj); > - cpu = POWERPC_CPU(cs); > + cpu = sc->threads[i] = POWERPC_CPU(obj); > cs->cpu_index = cc->core_id + i; > cpu->vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i; > if (kvm_enabled() && !kvm_vcpu_id_is_valid(cpu->vcpu_id)) { > @@ -192,7 +187,7 @@ static void spapr_cpu_core_realize(DeviceState *dev, > Error **errp) > } > > for (j = 0; j < cc->nr_threads; j++) { > - obj = sc->threads + j * size; > + obj = OBJECT(sc->threads[j]); > > spapr_cpu_core_realize_child(obj, spapr, &local_err); > if (local_err) { > @@ -203,7 +198,7 @@ static void spapr_cpu_core_realize(DeviceState *dev, > Error **errp) > > err: > while (--i >= 0) { > - obj = sc->threads + i * size; > + obj = OBJECT(sc->threads[i]); > object_unparent(obj); > } > g_free(sc->threads); > diff --git a/include/hw/ppc/spapr_cpu_core.h b/include/hw/ppc/spapr_cpu_core.h > index f2d48d6a6786..1129f344aa0c 100644 > --- a/include/hw/ppc/spapr_cpu_core.h > +++ b/include/hw/ppc/spapr_cpu_core.h > @@ -28,7 +28,7 @@ typedef struct sPAPRCPUCore { > CPUCore parent_obj; > > /*< public >*/ > - void *threads; > + PowerPCCPU **threads; > int node_id; > } sPAPRCPUCore; > > -- 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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