diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_xics.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_xics.c | 59 |
1 files changed, 27 insertions, 32 deletions
diff --git a/arch/powerpc/kvm/book3s_xics.c b/arch/powerpc/kvm/book3s_xics.c index c7620622c846..e48803e2918d 100644 --- a/arch/powerpc/kvm/book3s_xics.c +++ b/arch/powerpc/kvm/book3s_xics.c @@ -63,7 +63,7 @@ /* -- ICS routines -- */ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, - u32 new_irq); + u32 new_irq, bool check_resend); /* * Return value ideally indicates how the interrupt was handled, but no @@ -117,7 +117,7 @@ static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level) /* Test P=1, Q=0, this is the only case where we present */ if (pq_new == PQ_PRESENTED) - icp_deliver_irq(xics, NULL, irq); + icp_deliver_irq(xics, NULL, irq, false); /* Record which CPU this arrived on for passed-through interrupts */ if (state->host_irq) @@ -131,31 +131,14 @@ static void ics_check_resend(struct kvmppc_xics *xics, struct kvmppc_ics *ics, { int i; - unsigned long flags; - - local_irq_save(flags); - arch_spin_lock(&ics->lock); - for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) { struct ics_irq_state *state = &ics->irq_state[i]; - - if (!state->resend) - continue; - - state->resend = 0; - - XICS_DBG("resend %#x prio %#x\n", state->number, - state->priority); - - arch_spin_unlock(&ics->lock); - local_irq_restore(flags); - icp_deliver_irq(xics, icp, state->number); - local_irq_save(flags); - arch_spin_lock(&ics->lock); + if (state->resend) { + XICS_DBG("resend %#x prio %#x\n", state->number, + state->priority); + icp_deliver_irq(xics, icp, state->number, true); + } } - - arch_spin_unlock(&ics->lock); - local_irq_restore(flags); } static bool write_xive(struct kvmppc_xics *xics, struct kvmppc_ics *ics, @@ -209,7 +192,7 @@ int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority) state->masked_pending, state->resend); if (write_xive(xics, ics, state, server, priority, priority)) - icp_deliver_irq(xics, icp, irq); + icp_deliver_irq(xics, icp, irq, false); return 0; } @@ -262,7 +245,7 @@ int kvmppc_xics_int_on(struct kvm *kvm, u32 irq) if (write_xive(xics, ics, state, state->server, state->saved_priority, state->saved_priority)) - icp_deliver_irq(xics, icp, irq); + icp_deliver_irq(xics, icp, irq, false); return 0; } @@ -396,7 +379,7 @@ static bool icp_try_to_deliver(struct kvmppc_icp *icp, u32 irq, u8 priority, } static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, - u32 new_irq) + u32 new_irq, bool check_resend) { struct ics_irq_state *state; struct kvmppc_ics *ics; @@ -442,6 +425,10 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, } } + if (check_resend) + if (!state->resend) + goto out; + /* Clear the resend bit of that interrupt */ state->resend = 0; @@ -490,6 +477,7 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, arch_spin_unlock(&ics->lock); local_irq_restore(flags); new_irq = reject; + check_resend = 0; goto again; } } else { @@ -497,10 +485,16 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, * We failed to deliver the interrupt we need to set the * resend map bit and mark the ICS state as needing a resend */ - set_bit(ics->icsid, icp->resend_map); state->resend = 1; /* + * Make sure when checking resend, we don't miss the resend + * if resend_map bit is seen and cleared. + */ + smp_wmb(); + set_bit(ics->icsid, icp->resend_map); + + /* * If the need_resend flag got cleared in the ICP some time * between icp_try_to_deliver() atomic update and now, then * we know it might have missed the resend_map bit. So we @@ -511,6 +505,7 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, state->resend = 0; arch_spin_unlock(&ics->lock); local_irq_restore(flags); + check_resend = 0; goto again; } } @@ -702,7 +697,7 @@ static noinline int kvmppc_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, /* Handle reject */ if (reject && reject != XICS_IPI) - icp_deliver_irq(xics, icp, reject); + icp_deliver_irq(xics, icp, reject, false); /* Handle resend */ if (resend) @@ -782,7 +777,7 @@ static noinline void kvmppc_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) * attempt (see comments in icp_deliver_irq). */ if (reject && reject != XICS_IPI) - icp_deliver_irq(xics, icp, reject); + icp_deliver_irq(xics, icp, reject, false); } static int ics_eoi(struct kvm_vcpu *vcpu, u32 irq) @@ -818,7 +813,7 @@ static int ics_eoi(struct kvm_vcpu *vcpu, u32 irq) } while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old); if (pq_new & PQ_PRESENTED) - icp_deliver_irq(xics, icp, irq); + icp_deliver_irq(xics, icp, irq, false); kvm_notify_acked_irq(vcpu->kvm, 0, irq); @@ -1307,7 +1302,7 @@ static int xics_set_source(struct kvmppc_xics *xics, long irq, u64 addr) local_irq_restore(flags); if (val & KVM_XICS_PENDING) - icp_deliver_irq(xics, NULL, irqp->number); + icp_deliver_irq(xics, NULL, irqp->number, false); return 0; } |