On 02/23/2018 12:08 PM, David Hildenbrand wrote: > On 23.02.2018 12:04, Christian Borntraeger wrote: >> >> >> On 02/23/2018 12:00 PM, David Hildenbrand wrote: >>> On 23.02.2018 09:11, Christian Borntraeger wrote: >>>> We want to count IO exit requests in kvm_stat. At the same time >>>> we can get rid of the handle_noop function. >>>> >>>> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> >>>> --- >>>> arch/s390/include/asm/kvm_host.h | 1 + >>>> arch/s390/kvm/intercept.c | 19 +++++-------------- >>>> arch/s390/kvm/kvm-s390.c | 1 + >>>> 3 files changed, 7 insertions(+), 14 deletions(-) >>>> >>>> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h >>>> index 27918b15a8ba..22615af0b6e6 100644 >>>> --- a/arch/s390/include/asm/kvm_host.h >>>> +++ b/arch/s390/include/asm/kvm_host.h >>>> @@ -294,6 +294,7 @@ struct kvm_vcpu_stat { >>>> u64 exit_userspace; >>>> u64 exit_null; >>>> u64 exit_external_request; >>>> + u64 exit_io_request; >>>> u64 exit_external_interrupt; >>>> u64 exit_stop_request; >>>> u64 exit_validity; >>>> diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c >>>> index 07c6e81163bf..cad2ea216007 100644 >>>> --- a/arch/s390/kvm/intercept.c >>>> +++ b/arch/s390/kvm/intercept.c >>>> @@ -50,18 +50,6 @@ u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu) >>>> return ilen; >>>> } >>>> >>>> -static int handle_noop(struct kvm_vcpu *vcpu) >>>> -{ >>>> - switch (vcpu->arch.sie_block->icptcode) { >>>> - case 0x10: >>>> - vcpu->stat.exit_external_request++; >>>> - break; >>>> - default: >>>> - break; /* nothing */ >>>> - } >>>> - return 0; >>>> -} >>>> - >>>> static int handle_stop(struct kvm_vcpu *vcpu) >>>> { >>>> struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; >>>> @@ -458,15 +446,18 @@ static int handle_operexc(struct kvm_vcpu *vcpu) >>>> >>>> int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) >>>> { >>>> - int rc, per_rc = 0; >>>> + int rc = 0, per_rc = 0; >>>> >>>> if (kvm_is_ucontrol(vcpu->kvm)) >>>> return -EOPNOTSUPP; >>>> >>>> switch (vcpu->arch.sie_block->icptcode) { >>>> case ICPT_EXTREQ: >>>> + vcpu->stat.exit_external_request++; >>>> + break; >>>> case ICPT_IOREQ: >>>> - return handle_noop(vcpu); >>>> + vcpu->stat.exit_io_request++; >>>> + break; >>> >>> You now end up executing the code following this switch-case. >>> >>> But I assume vcpu->arch.sie_block->icptstatus will never indicate >>> instruction fetching, so this should be fine. >> >> To play safe I could replace the "break;" with "return 0;" ? > > Yes, please do. > > Can you also have a look if ICPT_KSS is correct? will have a look, but this will be another patch if you are correct. > > I can see that we don't retry the instruction. So > vcpu->arch.sie_block->icptstatus might remain set. > > 1. For ICPT_KSS, has the PSW been forwarded? I assume not. > 2. Can ICPT_KSS even set the icptstatus? > > As we're retrying, no event is to be injected. > > I assume a "return kvm_s390_skey_check_enable(vcpu)" can't hurt. > -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html