| Message ID | 159679993438.876294.7285654331498605426.stgit@bahia.lan |
|---|---|
| State | New |
| Headers | show |
| Series | spapr: Cleanups for XIVE | expand |
On 8/7/20 1:32 PM, Greg Kurz wrote: > Calls to the KVM XIVE device are guarded by kvm_irqchip_in_kernel(). This > ensures that QEMU won't try to use the device if KVM is disabled or if > an in-kernel irqchip isn't required. > > When using ic-mode=dual with the pseries machine, we have two possible > interrupt controllers: XIVE and XICS. The kvm_irqchip_in_kernel() helper > will return true as soon as any of the KVM device is created. It might > lure QEMU to think that the other one is also around, while it is not. > This is exactly what happens with ic-mode=dual at machine init when > claiming IRQ numbers, which must be done on all possible IRQ backends, > eg. RTAS event sources or the PHB0 LSI table : only the KVM XICS device > is active but we end up calling kvmppc_xive_source_reset_one() anyway, > which fails. This doesn't cause any trouble because of another bug : > kvmppc_xive_source_reset_one() lacks an error_setg() and callers don't > see the failure. > > Most of the other kvmppc_xive_* functions have similar xive->fd > checks to filter out the case when KVM XIVE isn't active. It > might look safer to have idempotent functions but it doesn't > really help to understand what's going on when debugging. > > Since we already have all the kvm_irqchip_in_kernel() in place, > also have the callers to check xive->fd as well before calling > KVM XIVE specific code. This is straight-forward for the spapr > specific XIVE code. Some more care is needed for the platform > agnostic XIVE code since it cannot access xive->fd directly. > Introduce new in_kernel() methods in some base XIVE classes > for this purpose and implement them only in spapr. > > In all cases, we still need to call kvm_irqchip_in_kernel() so that > compilers can optimize the kvmppc_xive_* calls away when CONFIG_KVM > isn't defined, thus avoiding the need for stubs. > > Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Cédric Le Goater <clg@kaod.org> > --- > v3: Method for XiveNotifierClass no longer needed > > v2: Introduce in_kernel() abstract methods in the base XIVE classes > --- > hw/intc/spapr_xive.c | 45 +++++++++++++++++++++++++++++++-------------- > hw/intc/xive.c | 25 +++++++++++++++++++------ > include/hw/ppc/xive.h | 1 + > 3 files changed, 51 insertions(+), 20 deletions(-) > > diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c > index 89c8cd96670b..3c84f64dc464 100644 > --- a/hw/intc/spapr_xive.c > +++ b/hw/intc/spapr_xive.c > @@ -148,12 +148,19 @@ static void spapr_xive_end_pic_print_info(SpaprXive *xive, XiveEND *end, > xive_end_queue_pic_print_info(end, 6, mon); > } > > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define spapr_xive_in_kernel(xive) \ > + (kvm_irqchip_in_kernel() && (xive)->fd != -1) > + > void spapr_xive_pic_print_info(SpaprXive *xive, Monitor *mon) > { > XiveSource *xsrc = &xive->source; > int i; > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_synchronize_state(xive, &local_err); > @@ -507,8 +514,10 @@ static const VMStateDescription vmstate_spapr_xive_eas = { > > static int vmstate_spapr_xive_pre_save(void *opaque) > { > - if (kvm_irqchip_in_kernel()) { > - return kvmppc_xive_pre_save(SPAPR_XIVE(opaque)); > + SpaprXive *xive = SPAPR_XIVE(opaque); > + > + if (spapr_xive_in_kernel(xive)) { > + return kvmppc_xive_pre_save(xive); > } > > return 0; > @@ -520,8 +529,10 @@ static int vmstate_spapr_xive_pre_save(void *opaque) > */ > static int spapr_xive_post_load(SpaprInterruptController *intc, int version_id) > { > - if (kvm_irqchip_in_kernel()) { > - return kvmppc_xive_post_load(SPAPR_XIVE(intc), version_id); > + SpaprXive *xive = SPAPR_XIVE(intc); > + > + if (spapr_xive_in_kernel(xive)) { > + return kvmppc_xive_post_load(xive, version_id); > } > > return 0; > @@ -564,7 +575,7 @@ static int spapr_xive_claim_irq(SpaprInterruptController *intc, int lisn, > xive_source_irq_set_lsi(xsrc, lisn); > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > return kvmppc_xive_source_reset_one(xsrc, lisn, errp); > } > > @@ -641,7 +652,7 @@ static void spapr_xive_set_irq(SpaprInterruptController *intc, int irq, int val) > { > SpaprXive *xive = SPAPR_XIVE(intc); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > kvmppc_xive_source_set_irq(&xive->source, irq, val); > } else { > xive_source_set_irq(&xive->source, irq, val); > @@ -749,11 +760,16 @@ static void spapr_xive_deactivate(SpaprInterruptController *intc) > > spapr_xive_mmio_set_enabled(xive, false); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > kvmppc_xive_disconnect(intc); > } > } > > +static bool spapr_xive_in_kernel_xptr(const XivePresenter *xptr) > +{ > + return spapr_xive_in_kernel(SPAPR_XIVE(xptr)); > +} > + > static void spapr_xive_class_init(ObjectClass *klass, void *data) > { > DeviceClass *dc = DEVICE_CLASS(klass); > @@ -788,6 +804,7 @@ static void spapr_xive_class_init(ObjectClass *klass, void *data) > sicc->post_load = spapr_xive_post_load; > > xpc->match_nvt = spapr_xive_match_nvt; > + xpc->in_kernel = spapr_xive_in_kernel_xptr; > } > > static const TypeInfo spapr_xive_info = { > @@ -1058,7 +1075,7 @@ static target_ulong h_int_set_source_config(PowerPCCPU *cpu, > new_eas.w = xive_set_field64(EAS_END_DATA, new_eas.w, eisn); > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_set_source_config(xive, lisn, &new_eas, &local_err); > @@ -1379,7 +1396,7 @@ static target_ulong h_int_set_queue_config(PowerPCCPU *cpu, > */ > > out: > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_set_queue_config(xive, end_blk, end_idx, &end, &local_err); > @@ -1480,7 +1497,7 @@ static target_ulong h_int_get_queue_config(PowerPCCPU *cpu, > args[2] = 0; > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_get_queue_config(xive, end_blk, end_idx, end, &local_err); > @@ -1642,7 +1659,7 @@ static target_ulong h_int_esb(PowerPCCPU *cpu, > return H_P3; > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > args[0] = kvmppc_xive_esb_rw(xsrc, lisn, offset, data, > flags & SPAPR_XIVE_ESB_STORE); > } else { > @@ -1717,7 +1734,7 @@ static target_ulong h_int_sync(PowerPCCPU *cpu, > * under KVM > */ > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_sync_source(xive, lisn, &local_err); > @@ -1761,7 +1778,7 @@ static target_ulong h_int_reset(PowerPCCPU *cpu, > > device_legacy_reset(DEVICE(xive)); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_reset(xive, &local_err); > diff --git a/hw/intc/xive.c b/hw/intc/xive.c > index 561d746cd1da..a453e8f4dcbe 100644 > --- a/hw/intc/xive.c > +++ b/hw/intc/xive.c > @@ -592,6 +592,17 @@ static const char * const xive_tctx_ring_names[] = { > "USER", "OS", "POOL", "PHYS", > }; > > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define xive_in_kernel(xptr) \ > + (kvm_irqchip_in_kernel() && \ > + ({ \ > + XivePresenterClass *xpc = XIVE_PRESENTER_GET_CLASS(xptr); \ > + xpc->in_kernel ? xpc->in_kernel(xptr) : false; \ > + })) > + > void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) > { > int cpu_index; > @@ -606,7 +617,7 @@ void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) > > cpu_index = tctx->cs ? tctx->cs->cpu_index : -1; > > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > Error *local_err = NULL; > > kvmppc_xive_cpu_synchronize_state(tctx, &local_err); > @@ -671,7 +682,7 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) > } > > /* Connect the presenter to the VCPU (required for CPU hotplug) */ > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > kvmppc_xive_cpu_connect(tctx, &local_err); > if (local_err) { > error_propagate(errp, local_err); > @@ -682,10 +693,11 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) > > static int vmstate_xive_tctx_pre_save(void *opaque) > { > + XiveTCTX *tctx = XIVE_TCTX(opaque); > Error *local_err = NULL; > > - if (kvm_irqchip_in_kernel()) { > - kvmppc_xive_cpu_get_state(XIVE_TCTX(opaque), &local_err); > + if (xive_in_kernel(tctx->xptr)) { > + kvmppc_xive_cpu_get_state(tctx, &local_err); > if (local_err) { > error_report_err(local_err); > return -1; > @@ -697,14 +709,15 @@ static int vmstate_xive_tctx_pre_save(void *opaque) > > static int vmstate_xive_tctx_post_load(void *opaque, int version_id) > { > + XiveTCTX *tctx = XIVE_TCTX(opaque); > Error *local_err = NULL; > > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > /* > * Required for hotplugged CPU, for which the state comes > * after all states of the machine. > */ > - kvmppc_xive_cpu_set_state(XIVE_TCTX(opaque), &local_err); > + kvmppc_xive_cpu_set_state(tctx, &local_err); > if (local_err) { > error_report_err(local_err); > return -1; > diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h > index 82a61eaca74f..2f3c5af810bb 100644 > --- a/include/hw/ppc/xive.h > +++ b/include/hw/ppc/xive.h > @@ -402,6 +402,7 @@ typedef struct XivePresenterClass { > uint8_t nvt_blk, uint32_t nvt_idx, > bool cam_ignore, uint8_t priority, > uint32_t logic_serv, XiveTCTXMatch *match); > + bool (*in_kernel)(const XivePresenter *xptr); > } XivePresenterClass; > > int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx, > >
Some more comments, because I still think there are some shortcuts. My feeling is that all the kvmppc_xive* could be part of a QOM interface defining how to use a kernel device backend. When the kernel IRQ device is not available, under TCG or under an hypervisor not advertising support at the KVM level, the QOM interface kernel device backend would be a no-op, else it would implement what the kvmppc_xive_* do today. So, it's something we would change like ->intc after an interrupt mode has been negotiated. It's an intuition regarding POWER10/XIVE2 and nested support which could need a different interface of the KVM XIVE device in the future. I don't think we need today but it would clarify some of the shortcuts. > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define spapr_xive_in_kernel(xive) \ > + (kvm_irqchip_in_kernel() && (xive)->fd != -1) > + Here, we have a shortcut. kvm_irqchip_in_kernel() is a compilation trick but the real handler : { return SPAPR_XIVE(xrtr)->fd != -1; } is a shortcut. We are using ->fd to know if QEMU is connected with a KVM device or not. > void spapr_xive_pic_print_info(SpaprXive *xive, Monitor *mon) > { > XiveSource *xsrc = &xive->source; > int i; > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_synchronize_state(xive, &local_err); With a QOM interface for a kernel device backend, this would become : XIVE_BACKEND_GET_CLASS(xive->backend)->synchronize_state(xive); and we could drop all the 'if' statement. Makes sense ? I think XICS behaves the same. Thanks, C.
On Fri, Aug 07, 2020 at 01:32:14PM +0200, Greg Kurz wrote: > Calls to the KVM XIVE device are guarded by kvm_irqchip_in_kernel(). This > ensures that QEMU won't try to use the device if KVM is disabled or if > an in-kernel irqchip isn't required. > > When using ic-mode=dual with the pseries machine, we have two possible > interrupt controllers: XIVE and XICS. The kvm_irqchip_in_kernel() helper > will return true as soon as any of the KVM device is created. It might > lure QEMU to think that the other one is also around, while it is not. > This is exactly what happens with ic-mode=dual at machine init when > claiming IRQ numbers, which must be done on all possible IRQ backends, > eg. RTAS event sources or the PHB0 LSI table : only the KVM XICS device > is active but we end up calling kvmppc_xive_source_reset_one() anyway, > which fails. This doesn't cause any trouble because of another bug : > kvmppc_xive_source_reset_one() lacks an error_setg() and callers don't > see the failure. > > Most of the other kvmppc_xive_* functions have similar xive->fd > checks to filter out the case when KVM XIVE isn't active. It > might look safer to have idempotent functions but it doesn't > really help to understand what's going on when debugging. > > Since we already have all the kvm_irqchip_in_kernel() in place, > also have the callers to check xive->fd as well before calling > KVM XIVE specific code. This is straight-forward for the spapr > specific XIVE code. Some more care is needed for the platform > agnostic XIVE code since it cannot access xive->fd directly. > Introduce new in_kernel() methods in some base XIVE classes > for this purpose and implement them only in spapr. > > In all cases, we still need to call kvm_irqchip_in_kernel() so that > compilers can optimize the kvmppc_xive_* calls away when CONFIG_KVM > isn't defined, thus avoiding the need for stubs. > > Signed-off-by: Greg Kurz <groug@kaod.org> Applied to ppc-for-5.2. > --- > v3: Method for XiveNotifierClass no longer needed > > v2: Introduce in_kernel() abstract methods in the base XIVE classes > --- > hw/intc/spapr_xive.c | 45 +++++++++++++++++++++++++++++++-------------- > hw/intc/xive.c | 25 +++++++++++++++++++------ > include/hw/ppc/xive.h | 1 + > 3 files changed, 51 insertions(+), 20 deletions(-) > > diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c > index 89c8cd96670b..3c84f64dc464 100644 > --- a/hw/intc/spapr_xive.c > +++ b/hw/intc/spapr_xive.c > @@ -148,12 +148,19 @@ static void spapr_xive_end_pic_print_info(SpaprXive *xive, XiveEND *end, > xive_end_queue_pic_print_info(end, 6, mon); > } > > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define spapr_xive_in_kernel(xive) \ > + (kvm_irqchip_in_kernel() && (xive)->fd != -1) > + > void spapr_xive_pic_print_info(SpaprXive *xive, Monitor *mon) > { > XiveSource *xsrc = &xive->source; > int i; > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_synchronize_state(xive, &local_err); > @@ -507,8 +514,10 @@ static const VMStateDescription vmstate_spapr_xive_eas = { > > static int vmstate_spapr_xive_pre_save(void *opaque) > { > - if (kvm_irqchip_in_kernel()) { > - return kvmppc_xive_pre_save(SPAPR_XIVE(opaque)); > + SpaprXive *xive = SPAPR_XIVE(opaque); > + > + if (spapr_xive_in_kernel(xive)) { > + return kvmppc_xive_pre_save(xive); > } > > return 0; > @@ -520,8 +529,10 @@ static int vmstate_spapr_xive_pre_save(void *opaque) > */ > static int spapr_xive_post_load(SpaprInterruptController *intc, int version_id) > { > - if (kvm_irqchip_in_kernel()) { > - return kvmppc_xive_post_load(SPAPR_XIVE(intc), version_id); > + SpaprXive *xive = SPAPR_XIVE(intc); > + > + if (spapr_xive_in_kernel(xive)) { > + return kvmppc_xive_post_load(xive, version_id); > } > > return 0; > @@ -564,7 +575,7 @@ static int spapr_xive_claim_irq(SpaprInterruptController *intc, int lisn, > xive_source_irq_set_lsi(xsrc, lisn); > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > return kvmppc_xive_source_reset_one(xsrc, lisn, errp); > } > > @@ -641,7 +652,7 @@ static void spapr_xive_set_irq(SpaprInterruptController *intc, int irq, int val) > { > SpaprXive *xive = SPAPR_XIVE(intc); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > kvmppc_xive_source_set_irq(&xive->source, irq, val); > } else { > xive_source_set_irq(&xive->source, irq, val); > @@ -749,11 +760,16 @@ static void spapr_xive_deactivate(SpaprInterruptController *intc) > > spapr_xive_mmio_set_enabled(xive, false); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > kvmppc_xive_disconnect(intc); > } > } > > +static bool spapr_xive_in_kernel_xptr(const XivePresenter *xptr) > +{ > + return spapr_xive_in_kernel(SPAPR_XIVE(xptr)); > +} > + > static void spapr_xive_class_init(ObjectClass *klass, void *data) > { > DeviceClass *dc = DEVICE_CLASS(klass); > @@ -788,6 +804,7 @@ static void spapr_xive_class_init(ObjectClass *klass, void *data) > sicc->post_load = spapr_xive_post_load; > > xpc->match_nvt = spapr_xive_match_nvt; > + xpc->in_kernel = spapr_xive_in_kernel_xptr; > } > > static const TypeInfo spapr_xive_info = { > @@ -1058,7 +1075,7 @@ static target_ulong h_int_set_source_config(PowerPCCPU *cpu, > new_eas.w = xive_set_field64(EAS_END_DATA, new_eas.w, eisn); > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_set_source_config(xive, lisn, &new_eas, &local_err); > @@ -1379,7 +1396,7 @@ static target_ulong h_int_set_queue_config(PowerPCCPU *cpu, > */ > > out: > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_set_queue_config(xive, end_blk, end_idx, &end, &local_err); > @@ -1480,7 +1497,7 @@ static target_ulong h_int_get_queue_config(PowerPCCPU *cpu, > args[2] = 0; > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_get_queue_config(xive, end_blk, end_idx, end, &local_err); > @@ -1642,7 +1659,7 @@ static target_ulong h_int_esb(PowerPCCPU *cpu, > return H_P3; > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > args[0] = kvmppc_xive_esb_rw(xsrc, lisn, offset, data, > flags & SPAPR_XIVE_ESB_STORE); > } else { > @@ -1717,7 +1734,7 @@ static target_ulong h_int_sync(PowerPCCPU *cpu, > * under KVM > */ > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_sync_source(xive, lisn, &local_err); > @@ -1761,7 +1778,7 @@ static target_ulong h_int_reset(PowerPCCPU *cpu, > > device_legacy_reset(DEVICE(xive)); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_reset(xive, &local_err); > diff --git a/hw/intc/xive.c b/hw/intc/xive.c > index 561d746cd1da..a453e8f4dcbe 100644 > --- a/hw/intc/xive.c > +++ b/hw/intc/xive.c > @@ -592,6 +592,17 @@ static const char * const xive_tctx_ring_names[] = { > "USER", "OS", "POOL", "PHYS", > }; > > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define xive_in_kernel(xptr) \ > + (kvm_irqchip_in_kernel() && \ > + ({ \ > + XivePresenterClass *xpc = XIVE_PRESENTER_GET_CLASS(xptr); \ > + xpc->in_kernel ? xpc->in_kernel(xptr) : false; \ > + })) > + > void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) > { > int cpu_index; > @@ -606,7 +617,7 @@ void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) > > cpu_index = tctx->cs ? tctx->cs->cpu_index : -1; > > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > Error *local_err = NULL; > > kvmppc_xive_cpu_synchronize_state(tctx, &local_err); > @@ -671,7 +682,7 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) > } > > /* Connect the presenter to the VCPU (required for CPU hotplug) */ > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > kvmppc_xive_cpu_connect(tctx, &local_err); > if (local_err) { > error_propagate(errp, local_err); > @@ -682,10 +693,11 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) > > static int vmstate_xive_tctx_pre_save(void *opaque) > { > + XiveTCTX *tctx = XIVE_TCTX(opaque); > Error *local_err = NULL; > > - if (kvm_irqchip_in_kernel()) { > - kvmppc_xive_cpu_get_state(XIVE_TCTX(opaque), &local_err); > + if (xive_in_kernel(tctx->xptr)) { > + kvmppc_xive_cpu_get_state(tctx, &local_err); > if (local_err) { > error_report_err(local_err); > return -1; > @@ -697,14 +709,15 @@ static int vmstate_xive_tctx_pre_save(void *opaque) > > static int vmstate_xive_tctx_post_load(void *opaque, int version_id) > { > + XiveTCTX *tctx = XIVE_TCTX(opaque); > Error *local_err = NULL; > > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > /* > * Required for hotplugged CPU, for which the state comes > * after all states of the machine. > */ > - kvmppc_xive_cpu_set_state(XIVE_TCTX(opaque), &local_err); > + kvmppc_xive_cpu_set_state(tctx, &local_err); > if (local_err) { > error_report_err(local_err); > return -1; > diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h > index 82a61eaca74f..2f3c5af810bb 100644 > --- a/include/hw/ppc/xive.h > +++ b/include/hw/ppc/xive.h > @@ -402,6 +402,7 @@ typedef struct XivePresenterClass { > uint8_t nvt_blk, uint32_t nvt_idx, > bool cam_ignore, uint8_t priority, > uint32_t logic_serv, XiveTCTXMatch *match); > + bool (*in_kernel)(const XivePresenter *xptr); > } XivePresenterClass; > > int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx, > >
diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c index 89c8cd96670b..3c84f64dc464 100644 --- a/hw/intc/spapr_xive.c +++ b/hw/intc/spapr_xive.c @@ -148,12 +148,19 @@ static void spapr_xive_end_pic_print_info(SpaprXive *xive, XiveEND *end, xive_end_queue_pic_print_info(end, 6, mon); } +/* + * kvm_irqchip_in_kernel() will cause the compiler to turn this + * info a nop if CONFIG_KVM isn't defined. + */ +#define spapr_xive_in_kernel(xive) \ + (kvm_irqchip_in_kernel() && (xive)->fd != -1) + void spapr_xive_pic_print_info(SpaprXive *xive, Monitor *mon) { XiveSource *xsrc = &xive->source; int i; - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { Error *local_err = NULL; kvmppc_xive_synchronize_state(xive, &local_err); @@ -507,8 +514,10 @@ static const VMStateDescription vmstate_spapr_xive_eas = { static int vmstate_spapr_xive_pre_save(void *opaque) { - if (kvm_irqchip_in_kernel()) { - return kvmppc_xive_pre_save(SPAPR_XIVE(opaque)); + SpaprXive *xive = SPAPR_XIVE(opaque); + + if (spapr_xive_in_kernel(xive)) { + return kvmppc_xive_pre_save(xive); } return 0; @@ -520,8 +529,10 @@ static int vmstate_spapr_xive_pre_save(void *opaque) */ static int spapr_xive_post_load(SpaprInterruptController *intc, int version_id) { - if (kvm_irqchip_in_kernel()) { - return kvmppc_xive_post_load(SPAPR_XIVE(intc), version_id); + SpaprXive *xive = SPAPR_XIVE(intc); + + if (spapr_xive_in_kernel(xive)) { + return kvmppc_xive_post_load(xive, version_id); } return 0; @@ -564,7 +575,7 @@ static int spapr_xive_claim_irq(SpaprInterruptController *intc, int lisn, xive_source_irq_set_lsi(xsrc, lisn); } - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { return kvmppc_xive_source_reset_one(xsrc, lisn, errp); } @@ -641,7 +652,7 @@ static void spapr_xive_set_irq(SpaprInterruptController *intc, int irq, int val) { SpaprXive *xive = SPAPR_XIVE(intc); - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { kvmppc_xive_source_set_irq(&xive->source, irq, val); } else { xive_source_set_irq(&xive->source, irq, val); @@ -749,11 +760,16 @@ static void spapr_xive_deactivate(SpaprInterruptController *intc) spapr_xive_mmio_set_enabled(xive, false); - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { kvmppc_xive_disconnect(intc); } } +static bool spapr_xive_in_kernel_xptr(const XivePresenter *xptr) +{ + return spapr_xive_in_kernel(SPAPR_XIVE(xptr)); +} + static void spapr_xive_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); @@ -788,6 +804,7 @@ static void spapr_xive_class_init(ObjectClass *klass, void *data) sicc->post_load = spapr_xive_post_load; xpc->match_nvt = spapr_xive_match_nvt; + xpc->in_kernel = spapr_xive_in_kernel_xptr; } static const TypeInfo spapr_xive_info = { @@ -1058,7 +1075,7 @@ static target_ulong h_int_set_source_config(PowerPCCPU *cpu, new_eas.w = xive_set_field64(EAS_END_DATA, new_eas.w, eisn); } - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { Error *local_err = NULL; kvmppc_xive_set_source_config(xive, lisn, &new_eas, &local_err); @@ -1379,7 +1396,7 @@ static target_ulong h_int_set_queue_config(PowerPCCPU *cpu, */ out: - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { Error *local_err = NULL; kvmppc_xive_set_queue_config(xive, end_blk, end_idx, &end, &local_err); @@ -1480,7 +1497,7 @@ static target_ulong h_int_get_queue_config(PowerPCCPU *cpu, args[2] = 0; } - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { Error *local_err = NULL; kvmppc_xive_get_queue_config(xive, end_blk, end_idx, end, &local_err); @@ -1642,7 +1659,7 @@ static target_ulong h_int_esb(PowerPCCPU *cpu, return H_P3; } - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { args[0] = kvmppc_xive_esb_rw(xsrc, lisn, offset, data, flags & SPAPR_XIVE_ESB_STORE); } else { @@ -1717,7 +1734,7 @@ static target_ulong h_int_sync(PowerPCCPU *cpu, * under KVM */ - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { Error *local_err = NULL; kvmppc_xive_sync_source(xive, lisn, &local_err); @@ -1761,7 +1778,7 @@ static target_ulong h_int_reset(PowerPCCPU *cpu, device_legacy_reset(DEVICE(xive)); - if (kvm_irqchip_in_kernel()) { + if (spapr_xive_in_kernel(xive)) { Error *local_err = NULL; kvmppc_xive_reset(xive, &local_err); diff --git a/hw/intc/xive.c b/hw/intc/xive.c index 561d746cd1da..a453e8f4dcbe 100644 --- a/hw/intc/xive.c +++ b/hw/intc/xive.c @@ -592,6 +592,17 @@ static const char * const xive_tctx_ring_names[] = { "USER", "OS", "POOL", "PHYS", }; +/* + * kvm_irqchip_in_kernel() will cause the compiler to turn this + * info a nop if CONFIG_KVM isn't defined. + */ +#define xive_in_kernel(xptr) \ + (kvm_irqchip_in_kernel() && \ + ({ \ + XivePresenterClass *xpc = XIVE_PRESENTER_GET_CLASS(xptr); \ + xpc->in_kernel ? xpc->in_kernel(xptr) : false; \ + })) + void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) { int cpu_index; @@ -606,7 +617,7 @@ void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) cpu_index = tctx->cs ? tctx->cs->cpu_index : -1; - if (kvm_irqchip_in_kernel()) { + if (xive_in_kernel(tctx->xptr)) { Error *local_err = NULL; kvmppc_xive_cpu_synchronize_state(tctx, &local_err); @@ -671,7 +682,7 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) } /* Connect the presenter to the VCPU (required for CPU hotplug) */ - if (kvm_irqchip_in_kernel()) { + if (xive_in_kernel(tctx->xptr)) { kvmppc_xive_cpu_connect(tctx, &local_err); if (local_err) { error_propagate(errp, local_err); @@ -682,10 +693,11 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) static int vmstate_xive_tctx_pre_save(void *opaque) { + XiveTCTX *tctx = XIVE_TCTX(opaque); Error *local_err = NULL; - if (kvm_irqchip_in_kernel()) { - kvmppc_xive_cpu_get_state(XIVE_TCTX(opaque), &local_err); + if (xive_in_kernel(tctx->xptr)) { + kvmppc_xive_cpu_get_state(tctx, &local_err); if (local_err) { error_report_err(local_err); return -1; @@ -697,14 +709,15 @@ static int vmstate_xive_tctx_pre_save(void *opaque) static int vmstate_xive_tctx_post_load(void *opaque, int version_id) { + XiveTCTX *tctx = XIVE_TCTX(opaque); Error *local_err = NULL; - if (kvm_irqchip_in_kernel()) { + if (xive_in_kernel(tctx->xptr)) { /* * Required for hotplugged CPU, for which the state comes * after all states of the machine. */ - kvmppc_xive_cpu_set_state(XIVE_TCTX(opaque), &local_err); + kvmppc_xive_cpu_set_state(tctx, &local_err); if (local_err) { error_report_err(local_err); return -1; diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h index 82a61eaca74f..2f3c5af810bb 100644 --- a/include/hw/ppc/xive.h +++ b/include/hw/ppc/xive.h @@ -402,6 +402,7 @@ typedef struct XivePresenterClass { uint8_t nvt_blk, uint32_t nvt_idx, bool cam_ignore, uint8_t priority, uint32_t logic_serv, XiveTCTXMatch *match); + bool (*in_kernel)(const XivePresenter *xptr); } XivePresenterClass; int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx,
Calls to the KVM XIVE device are guarded by kvm_irqchip_in_kernel(). This ensures that QEMU won't try to use the device if KVM is disabled or if an in-kernel irqchip isn't required. When using ic-mode=dual with the pseries machine, we have two possible interrupt controllers: XIVE and XICS. The kvm_irqchip_in_kernel() helper will return true as soon as any of the KVM device is created. It might lure QEMU to think that the other one is also around, while it is not. This is exactly what happens with ic-mode=dual at machine init when claiming IRQ numbers, which must be done on all possible IRQ backends, eg. RTAS event sources or the PHB0 LSI table : only the KVM XICS device is active but we end up calling kvmppc_xive_source_reset_one() anyway, which fails. This doesn't cause any trouble because of another bug : kvmppc_xive_source_reset_one() lacks an error_setg() and callers don't see the failure. Most of the other kvmppc_xive_* functions have similar xive->fd checks to filter out the case when KVM XIVE isn't active. It might look safer to have idempotent functions but it doesn't really help to understand what's going on when debugging. Since we already have all the kvm_irqchip_in_kernel() in place, also have the callers to check xive->fd as well before calling KVM XIVE specific code. This is straight-forward for the spapr specific XIVE code. Some more care is needed for the platform agnostic XIVE code since it cannot access xive->fd directly. Introduce new in_kernel() methods in some base XIVE classes for this purpose and implement them only in spapr. In all cases, we still need to call kvm_irqchip_in_kernel() so that compilers can optimize the kvmppc_xive_* calls away when CONFIG_KVM isn't defined, thus avoiding the need for stubs. Signed-off-by: Greg Kurz <groug@kaod.org> --- v3: Method for XiveNotifierClass no longer needed v2: Introduce in_kernel() abstract methods in the base XIVE classes --- hw/intc/spapr_xive.c | 45 +++++++++++++++++++++++++++++++-------------- hw/intc/xive.c | 25 +++++++++++++++++++------ include/hw/ppc/xive.h | 1 + 3 files changed, 51 insertions(+), 20 deletions(-)