| Message ID | 20180117193757.73471-3-borntraeger@de.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | s390x/kvm: implement new hardware/firmware features | expand |
On 17.01.2018 20:37, Christian Borntraeger wrote: > We need to handle the bpb control on reset and migration. Normally > stfle.82 is transparent (and the normal guest part works without > hypervisor activity). To prevent any issues we require full > host kernel support for this feature. > > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > --- > target/s390x/cpu.c | 1 + > target/s390x/cpu.h | 1 + > target/s390x/cpu_features.c | 1 + > target/s390x/cpu_features_def.h | 1 + > target/s390x/gen-features.c | 1 + > target/s390x/kvm.c | 14 ++++++++++++++ > target/s390x/machine.c | 17 +++++++++++++++++ > 7 files changed, 36 insertions(+) > > diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c > index ae3cee9..1577b2c 100644 > --- a/target/s390x/cpu.c > +++ b/target/s390x/cpu.c > @@ -89,6 +89,7 @@ static void s390_cpu_reset(CPUState *s) > CPUS390XState *env = &cpu->env; > > env->pfault_token = -1UL; > + env->bpbc = 0; As this is effectively only 1 bit, I wonder if we should also make that clear in QEMU bool bpbc, VMSTATE_BOOL ... Apart from that, looks sane.
On 17.01.2018 22:12, David Hildenbrand wrote: > On 17.01.2018 20:37, Christian Borntraeger wrote: >> We need to handle the bpb control on reset and migration. Normally >> stfle.82 is transparent (and the normal guest part works without >> hypervisor activity). To prevent any issues we require full >> host kernel support for this feature. >> >> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> >> --- >> target/s390x/cpu.c | 1 + >> target/s390x/cpu.h | 1 + >> target/s390x/cpu_features.c | 1 + >> target/s390x/cpu_features_def.h | 1 + >> target/s390x/gen-features.c | 1 + >> target/s390x/kvm.c | 14 ++++++++++++++ >> target/s390x/machine.c | 17 +++++++++++++++++ >> 7 files changed, 36 insertions(+) >> >> diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c >> index ae3cee9..1577b2c 100644 >> --- a/target/s390x/cpu.c >> +++ b/target/s390x/cpu.c >> @@ -89,6 +89,7 @@ static void s390_cpu_reset(CPUState *s) >> CPUS390XState *env = &cpu->env; >> >> env->pfault_token = -1UL; >> + env->bpbc = 0; > > As this is effectively only 1 bit, I wonder if we should also make that > clear in QEMU > > bool bpbc, VMSTATE_BOOL ... > > Apart from that, looks sane. I had the same thought when reading the patch ... apart from that, also looks good to me. Thomas
diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c index ae3cee9..1577b2c 100644 --- a/target/s390x/cpu.c +++ b/target/s390x/cpu.c @@ -89,6 +89,7 @@ static void s390_cpu_reset(CPUState *s) CPUS390XState *env = &cpu->env; env->pfault_token = -1UL; + env->bpbc = 0; scc->parent_reset(s); cpu->env.sigp_order = 0; s390_cpu_set_state(CPU_STATE_STOPPED, cpu); diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h index 1a8b6b9..8514905 100644 --- a/target/s390x/cpu.h +++ b/target/s390x/cpu.h @@ -93,6 +93,7 @@ struct CPUS390XState { uint32_t fpc; /* floating-point control register */ uint32_t cc_op; + uint8_t bpbc; /* branch prediction blocking */ float_status fpu_status; /* passed to softfloat lib */ diff --git a/target/s390x/cpu_features.c b/target/s390x/cpu_features.c index 31a4676..5d1c210 100644 --- a/target/s390x/cpu_features.c +++ b/target/s390x/cpu_features.c @@ -89,6 +89,7 @@ static const S390FeatDef s390_features[] = { FEAT_INIT("msa4-base", S390_FEAT_TYPE_STFL, 77, "Message-security-assist-extension-4 facility (excluding subfunctions)"), FEAT_INIT("edat2", S390_FEAT_TYPE_STFL, 78, "Enhanced-DAT facility 2"), FEAT_INIT("dfppc", S390_FEAT_TYPE_STFL, 80, "Decimal-floating-point packed-conversion facility"), + FEAT_INIT("bpb", S390_FEAT_TYPE_STFL, 82, "Branch Prediction Blocking"), FEAT_INIT("vx", S390_FEAT_TYPE_STFL, 129, "Vector facility"), FEAT_INIT("iep", S390_FEAT_TYPE_STFL, 130, "Instruction-execution-protection facility"), FEAT_INIT("sea_esop2", S390_FEAT_TYPE_STFL, 131, "Side-effect-access facility and Enhanced-suppression-on-protection facility 2"), diff --git a/target/s390x/cpu_features_def.h b/target/s390x/cpu_features_def.h index 4b6d4e9..4487cfd 100644 --- a/target/s390x/cpu_features_def.h +++ b/target/s390x/cpu_features_def.h @@ -80,6 +80,7 @@ typedef enum { S390_FEAT_MSA_EXT_4, S390_FEAT_EDAT_2, S390_FEAT_DFP_PACKED_CONVERSION, + S390_FEAT_BPB, S390_FEAT_VECTOR, S390_FEAT_INSTRUCTION_EXEC_PROT, S390_FEAT_SIDE_EFFECT_ACCESS_ESOP2, diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c index b24f6ad..95ee870 100644 --- a/target/s390x/gen-features.c +++ b/target/s390x/gen-features.c @@ -357,6 +357,7 @@ static uint16_t full_GEN7_GA1[] = { S390_FEAT_SIE_GPERE, S390_FEAT_SIE_IB, S390_FEAT_SIE_CEI, + S390_FEAT_BPB, }; static uint16_t full_GEN7_GA2[] = { diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c index 6a18a41..8736001 100644 --- a/target/s390x/kvm.c +++ b/target/s390x/kvm.c @@ -490,6 +490,11 @@ int kvm_arch_put_registers(CPUState *cs, int level) cs->kvm_run->kvm_dirty_regs |= KVM_SYNC_GSCB; } + if (can_sync_regs(cs, KVM_SYNC_BPBC)) { + cs->kvm_run->s.regs.bpbc = env->bpbc; + cs->kvm_run->kvm_dirty_regs |= KVM_SYNC_BPBC; + } + /* Finally the prefix */ if (can_sync_regs(cs, KVM_SYNC_PREFIX)) { cs->kvm_run->s.regs.prefix = env->psa; @@ -600,6 +605,10 @@ int kvm_arch_get_registers(CPUState *cs) memcpy(env->gscb, cs->kvm_run->s.regs.gscb, 32); } + if (can_sync_regs(cs, KVM_SYNC_BPBC)) { + env->bpbc = cs->kvm_run->s.regs.bpbc; + } + /* pfault parameters */ if (can_sync_regs(cs, KVM_SYNC_PFAULT)) { env->pfault_token = cs->kvm_run->s.regs.pft; @@ -2278,6 +2287,11 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model, Error **errp) clear_bit(S390_FEAT_CMM_NT, model->features); } + /* bpb needs kernel support for migration, VSIE and reset */ + if (!kvm_check_extension(kvm_state, KVM_CAP_S390_BPB)) { + clear_bit(S390_FEAT_BPB, model->features); + } + /* We emulate a zPCI bus and AEN, therefore we don't need HW support */ if (pci_available) { set_bit(S390_FEAT_ZPCI, model->features); diff --git a/target/s390x/machine.c b/target/s390x/machine.c index b78f326..4aac456 100644 --- a/target/s390x/machine.c +++ b/target/s390x/machine.c @@ -194,6 +194,22 @@ const VMStateDescription vmstate_gscb = { } }; +static bool bpbc_needed(void *opaque) +{ + return s390_has_feat(S390_FEAT_BPB); +} + +const VMStateDescription vmstate_bpbc = { + .name = "cpu/bpbc", + .version_id = 1, + .minimum_version_id = 1, + .needed = bpbc_needed, + .fields = (VMStateField[]) { + VMSTATE_UINT8(env.bpbc, S390CPU), + VMSTATE_END_OF_LIST() + } +}; + const VMStateDescription vmstate_s390_cpu = { .name = "cpu", .post_load = cpu_post_load, @@ -228,6 +244,7 @@ const VMStateDescription vmstate_s390_cpu = { &vmstate_riccb, &vmstate_exval, &vmstate_gscb, + &vmstate_bpbc, NULL }, };
We need to handle the bpb control on reset and migration. Normally stfle.82 is transparent (and the normal guest part works without hypervisor activity). To prevent any issues we require full host kernel support for this feature. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> --- target/s390x/cpu.c | 1 + target/s390x/cpu.h | 1 + target/s390x/cpu_features.c | 1 + target/s390x/cpu_features_def.h | 1 + target/s390x/gen-features.c | 1 + target/s390x/kvm.c | 14 ++++++++++++++ target/s390x/machine.c | 17 +++++++++++++++++ 7 files changed, 36 insertions(+)