On Fri, 18 Jan 2019 13:26:29 +0100
Cédric Le Goater <c...@kaod.org> wrote:
> On 1/17/19 6:14 PM, Greg Kurz wrote:
> > The current code assumes that an interrupt is allocated as soon as its
> > type is set to MSI or LSI. PHB hotplug will require to be able to set
> > the type of an interrupt before actually allocating it.
> >
> > Disintricate type setting from allocation by using another flag bit for
> > the latter. Introduce a new ics_claim_irq() function for allocation. The
> > behavior of aborting if the same irq gets allocated twice is kept.
> >
> > ics_set_irq_type() now only sets the type to MSI or LSI. It doesn't bring
> > anything to abort if the type was already set before. Drop the assert
> > and XICS_FLAGS_IRQ_MASK on the way.
> >
> > Older QEMUs don't know about XICS_FLAGS_IRQ_CLAIMED. In order to safely
> > handle incoming migration, we must fix the irq flags. This is done at
> > post load thanks to a compat property. We don't need to do anything for
> > backward migration since older machines only care for the irq type.
> >
> > Signed-off-by: Greg Kurz <gr...@kaod.org>
>
>
> Reviewed-by: Cédric Le Goater <c...@kaod.org>
>
> In case of a respin, may be transform macro ICS_IRQ_FREE() in a static
> inline helper.
>
Yeah, there will be a respin (see my other mail in this thread) and I'll
just do that.
> Thanks,
>
> C.
>
> > ---
> > hw/core/machine.c | 4 ++++
> > hw/intc/xics.c | 28 +++++++++++++++++++++++++---
> > hw/ppc/pnv_psi.c | 1 +
> > hw/ppc/spapr_irq.c | 4 +---
> > include/hw/ppc/xics.h | 8 ++++++--
> > 5 files changed, 37 insertions(+), 8 deletions(-)
> >
> > diff --git a/hw/core/machine.c b/hw/core/machine.c
> > index 1a0a9ab1117a..536a34092367 100644
> > --- a/hw/core/machine.c
> > +++ b/hw/core/machine.c
> > @@ -25,6 +25,10 @@
> >
> > GlobalProperty hw_compat_3_1[] = {
> > {
> > + .driver = "ics-base",
> > + .property = "has-claimed-flag",
> > + .value = "off",
> > + },{
> > .driver = "pcie-root-port",
> > .property = "x-speed",
> > .value = "2_5",
> > diff --git a/hw/intc/xics.c b/hw/intc/xics.c
> > index 16e8ffa2aaf7..82cf04548907 100644
> > --- a/hw/intc/xics.c
> > +++ b/hw/intc/xics.c
> > @@ -75,7 +75,7 @@ void ics_pic_print_info(ICSState *ics, Monitor *mon)
> > for (i = 0; i < ics->nr_irqs; i++) {
> > ICSIRQState *irq = ics->irqs + i;
> >
> > - if (!(irq->flags & XICS_FLAGS_IRQ_MASK)) {
> > + if (!(irq->flags & XICS_FLAGS_IRQ_CLAIMED)) {
> > continue;
> > }
> > monitor_printf(mon, " %4x %s %02x %02x\n",
> > @@ -662,6 +662,22 @@ static int ics_base_dispatch_post_load(void *opaque,
> > int version_id)
> > ICSState *ics = opaque;
> > ICSStateClass *info = ICS_BASE_GET_CLASS(ics);
> >
> > + if (!ics->has_claimed_flag) {
> > + int i;
> > +
> > + for (i = 0; i < ics->nr_irqs; i++) {
> > + ICSIRQState *irq = ics->irqs + i;
> > +
> > + /*
> > + * For older machines, allocating the irq and setting its type
> > is
> > + * the same thing.
> > + */
> > + if (irq->flags & (XICS_FLAGS_IRQ_LSI| XICS_FLAGS_IRQ_MSI)) {
> > + irq->flags |= XICS_FLAGS_IRQ_CLAIMED;
> > + }
> > + }
> > + }
> > +
> > if (info->post_load) {
> > return info->post_load(ics, version_id);
> > }
> > @@ -702,6 +718,7 @@ static const VMStateDescription vmstate_ics_base = {
> >
> > static Property ics_base_properties[] = {
> > DEFINE_PROP_UINT32("nr-irqs", ICSState, nr_irqs, 0),
> > + DEFINE_PROP_BOOL("has-claimed-flag", ICSState, has_claimed_flag, true),
> > DEFINE_PROP_END_OF_LIST(),
> > };
> >
> > @@ -741,10 +758,15 @@ ICPState *xics_icp_get(XICSFabric *xi, int server)
> > return xic->icp_get(xi, server);
> > }
> >
> > -void ics_set_irq_type(ICSState *ics, int srcno, bool lsi)
> > +void ics_claim_irq(ICSState *ics, int srcno)
> > {
> > - assert(!(ics->irqs[srcno].flags & XICS_FLAGS_IRQ_MASK));
> > + assert(ICS_IRQ_FREE(ics, srcno));
> > +
> > + ics->irqs[srcno].flags |= XICS_FLAGS_IRQ_CLAIMED;
> > +}
> >
> > +void ics_set_irq_type(ICSState *ics, int srcno, bool lsi)
> > +{
> > ics->irqs[srcno].flags |=
> > lsi ? XICS_FLAGS_IRQ_LSI : XICS_FLAGS_IRQ_MSI;
> > }
> > diff --git a/hw/ppc/pnv_psi.c b/hw/ppc/pnv_psi.c
> > index 8ced09506321..ced34e1119dc 100644
> > --- a/hw/ppc/pnv_psi.c
> > +++ b/hw/ppc/pnv_psi.c
> > @@ -488,6 +488,7 @@ static void pnv_psi_realize(DeviceState *dev, Error
> > **errp)
> >
> > for (i = 0; i < ics->nr_irqs; i++) {
> > ics_set_irq_type(ics, i, true);
> > + ics_claim_irq(ics, i);
> > }
> >
> > psi->qirqs = qemu_allocate_irqs(ics_simple_set_irq, ics, ics->nr_irqs);
> > diff --git a/hw/ppc/spapr_irq.c b/hw/ppc/spapr_irq.c
> > index 1da7a32348fc..86c712d15382 100644
> > --- a/hw/ppc/spapr_irq.c
> > +++ b/hw/ppc/spapr_irq.c
> > @@ -125,9 +125,6 @@ error:
> > error_propagate(errp, local_err);
> > }
> >
> > -#define ICS_IRQ_FREE(ics, srcno) \
> > - (!((ics)->irqs[(srcno)].flags & (XICS_FLAGS_IRQ_MASK)))
> > -
> > static int spapr_irq_claim_xics(sPAPRMachineState *spapr, int irq, bool
> > lsi,
> > Error **errp)
> > {
> > @@ -146,6 +143,7 @@ static int spapr_irq_claim_xics(sPAPRMachineState
> > *spapr, int irq, bool lsi,
> > }
> >
> > ics_set_irq_type(ics, irq - ics->offset, lsi);
> > + ics_claim_irq(ics, irq - ics->offset);
> > return 0;
> > }
> >
> > diff --git a/include/hw/ppc/xics.h b/include/hw/ppc/xics.h
> > index fad786e8b22d..e3be5cc663c5 100644
> > --- a/include/hw/ppc/xics.h
> > +++ b/include/hw/ppc/xics.h
> > @@ -131,6 +131,7 @@ struct ICSState {
> > /*< public >*/
> > uint32_t nr_irqs;
> > uint32_t offset;
> > + bool has_claimed_flag;
> > ICSIRQState *irqs;
> > XICSFabric *xics;
> > };
> > @@ -153,13 +154,15 @@ struct ICSIRQState {
> > #define XICS_STATUS_PRESENTED 0x10
> > #define XICS_STATUS_QUEUED 0x20
> > uint8_t status;
> > -/* (flags & XICS_FLAGS_IRQ_MASK) == 0 means the interrupt is not allocated
> > */
> > #define XICS_FLAGS_IRQ_LSI 0x1
> > #define XICS_FLAGS_IRQ_MSI 0x2
> > -#define XICS_FLAGS_IRQ_MASK 0x3
> > +#define XICS_FLAGS_IRQ_CLAIMED 0x4
> > uint8_t flags;
> > };
> >
> > +#define ICS_IRQ_FREE(ics, srcno) \
> > + (!((ics)->irqs[(srcno)].flags & (XICS_FLAGS_IRQ_CLAIMED)))
> > +
> > struct XICSFabric {
> > Object parent;
> > };
> > @@ -193,6 +196,7 @@ void ics_simple_write_xive(ICSState *ics, int nr, int
> > server,
> > void ics_simple_set_irq(void *opaque, int srcno, int val);
> > void ics_kvm_set_irq(void *opaque, int srcno, int val);
> >
> > +void ics_claim_irq(ICSState *ics, int srcno);
> > void ics_set_irq_type(ICSState *ics, int srcno, bool lsi);
> > void icp_pic_print_info(ICPState *icp, Monitor *mon);
> > void ics_pic_print_info(ICSState *ics, Monitor *mon);
> >
>
