diff options
Diffstat (limited to 'arch/s390/kvm/diag.c')
| -rw-r--r-- | arch/s390/kvm/diag.c | 54 |
1 files changed, 41 insertions, 13 deletions
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c index 3fb54ec2cf3e..807fa9da1e72 100644 --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -2,7 +2,7 @@ /* * handling diagnose instructions * - * Copyright IBM Corp. 2008, 2011 + * Copyright IBM Corp. 2008, 2020 * * Author(s): Carsten Otte <cotte@de.ibm.com> * Christian Borntraeger <borntraeger@de.ibm.com> @@ -10,7 +10,6 @@ #include <linux/kvm.h> #include <linux/kvm_host.h> -#include <asm/pgalloc.h> #include <asm/gmap.h> #include <asm/virtio-ccw.h> #include "kvm-s390.h" @@ -25,7 +24,7 @@ static int diag_release_pages(struct kvm_vcpu *vcpu) start = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4]; end = vcpu->run->s.regs.gprs[vcpu->arch.sie_block->ipa & 0xf] + PAGE_SIZE; - vcpu->stat.diagnose_10++; + vcpu->stat.instruction_diagnose_10++; if (start & ~PAGE_MASK || end & ~PAGE_MASK || start >= end || start < 2 * PAGE_SIZE) @@ -75,7 +74,7 @@ static int __diag_page_ref_service(struct kvm_vcpu *vcpu) VCPU_EVENT(vcpu, 3, "diag page reference parameter block at 0x%llx", vcpu->run->s.regs.gprs[rx]); - vcpu->stat.diagnose_258++; + vcpu->stat.instruction_diagnose_258++; if (vcpu->run->s.regs.gprs[rx] & 7) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); rc = read_guest(vcpu, vcpu->run->s.regs.gprs[rx], rx, &parm, sizeof(parm)); @@ -146,18 +145,31 @@ static int __diag_page_ref_service(struct kvm_vcpu *vcpu) static int __diag_time_slice_end(struct kvm_vcpu *vcpu) { VCPU_EVENT(vcpu, 5, "%s", "diag time slice end"); - vcpu->stat.diagnose_44++; + vcpu->stat.instruction_diagnose_44++; kvm_vcpu_on_spin(vcpu, true); return 0; } +static int forward_cnt; +static unsigned long cur_slice; + +static int diag9c_forwarding_overrun(void) +{ + /* Reset the count on a new slice */ + if (time_after(jiffies, cur_slice)) { + cur_slice = jiffies; + forward_cnt = diag9c_forwarding_hz / HZ; + } + return forward_cnt-- <= 0 ? 1 : 0; +} + static int __diag_time_slice_end_directed(struct kvm_vcpu *vcpu) { struct kvm_vcpu *tcpu; int tid; tid = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4]; - vcpu->stat.diagnose_9c++; + vcpu->stat.instruction_diagnose_9c++; /* yield to self */ if (tid == vcpu->vcpu_id) @@ -168,9 +180,21 @@ static int __diag_time_slice_end_directed(struct kvm_vcpu *vcpu) if (!tcpu) goto no_yield; - /* target already running */ - if (READ_ONCE(tcpu->cpu) >= 0) - goto no_yield; + /* target guest VCPU already running */ + if (READ_ONCE(tcpu->cpu) >= 0) { + if (!diag9c_forwarding_hz || diag9c_forwarding_overrun()) + goto no_yield; + + /* target host CPU already running */ + if (!vcpu_is_preempted(tcpu->cpu)) + goto no_yield; + smp_yield_cpu(tcpu->cpu); + VCPU_EVENT(vcpu, 5, + "diag time slice end directed to %d: yield forwarded", + tid); + vcpu->stat.diag_9c_forward++; + return 0; + } if (kvm_vcpu_yield_to(tcpu) <= 0) goto no_yield; @@ -179,7 +203,7 @@ static int __diag_time_slice_end_directed(struct kvm_vcpu *vcpu) return 0; no_yield: VCPU_EVENT(vcpu, 5, "diag time slice end directed to %d: ignored", tid); - vcpu->stat.diagnose_9c_ignored++; + vcpu->stat.diag_9c_ignored++; return 0; } @@ -189,7 +213,7 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu) unsigned long subcode = vcpu->run->s.regs.gprs[reg] & 0xffff; VCPU_EVENT(vcpu, 3, "diag ipl functions, subcode %lx", subcode); - vcpu->stat.diagnose_308++; + vcpu->stat.instruction_diagnose_308++; switch (subcode) { case 3: vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR; @@ -201,6 +225,10 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu) return -EOPNOTSUPP; } + /* + * no need to check the return value of vcpu_stop as it can only have + * an error for protvirt, but protvirt means user cpu state + */ if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) kvm_s390_vcpu_stop(vcpu); vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM; @@ -217,7 +245,7 @@ static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu) { int ret; - vcpu->stat.diagnose_500++; + vcpu->stat.instruction_diagnose_500++; /* No virtio-ccw notification? Get out quickly. */ if (!vcpu->kvm->arch.css_support || (vcpu->run->s.regs.gprs[1] != KVM_S390_VIRTIO_CCW_NOTIFY)) @@ -271,7 +299,7 @@ int kvm_s390_handle_diag(struct kvm_vcpu *vcpu) case 0x500: return __diag_virtio_hypercall(vcpu); default: - vcpu->stat.diagnose_other++; + vcpu->stat.instruction_diagnose_other++; return -EOPNOTSUPP; } } |