On 02/13/2015 12:22 AM, Alex Bennée wrote:
>
> Wei Huang <wei@xxxxxxxxxx> writes:
>
>> This patch extends trace_kvm_exit() to include KVM exit reasons
>> (i.e. EC of HSR). The tracing function then dumps both exit reason
>> and PC of vCPU, shown as the following. Tracing tools can use this
>> new exit_reason field to better understand the behavior of guest VMs.
>>
>> 886.301252: kvm_exit: HSR_EC: 0x0024, PC:
>> 0xfffffe0000506b28
>
> Ah I also have a similar patch but I've also added LR and CONTEXTIDR to
> the record. The first helps when PC is in a widely used helper function
> and the second gives you an idea of what userspace process the guest is
> currently dealing with.
>
Sounds useful to me. You can either create a separate patch; or ask
Paolo to merge yours with existing one and put your name as signed-off-by.
> If people are interested I can clean it up and submit (I have a bunch of
> TRACE_EVENTs I've been adding while debugging migration).
I can help review the patches...
>
>>
>> Signed-off-by: Wei Huang <wei@xxxxxxxxxx>
>> ---
>> arch/arm/kvm/arm.c | 2 +-
>> arch/arm/kvm/trace.h | 10 +++++++---
>> 2 files changed, 8 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
>> index 0b0d58a..4a00131 100644
>> --- a/arch/arm/kvm/arm.c
>> +++ b/arch/arm/kvm/arm.c
>> @@ -533,7 +533,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
>>
>> vcpu->mode = OUTSIDE_GUEST_MODE;
>> kvm_guest_exit();
>> - trace_kvm_exit(*vcpu_pc(vcpu));
>> + trace_kvm_exit(kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
>> /*
>> * We may have taken a host interrupt in HYP mode (ie
>> * while executing the guest). This interrupt is still
>> diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
>> index 5665a16..b7427d4 100644
>> --- a/arch/arm/kvm/trace.h
>> +++ b/arch/arm/kvm/trace.h
>> @@ -25,18 +25,22 @@ TRACE_EVENT(kvm_entry,
>> );
>>
>> TRACE_EVENT(kvm_exit,
>> - TP_PROTO(unsigned long vcpu_pc),
>> - TP_ARGS(vcpu_pc),
>> + TP_PROTO(unsigned int exit_reason, unsigned long vcpu_pc),
>> + TP_ARGS(exit_reason, vcpu_pc),
>>
>> TP_STRUCT__entry(
>> + __field( unsigned int, exit_reason )
>> __field( unsigned long, vcpu_pc )
>> ),
>>
>> TP_fast_assign(
>> + __entry->exit_reason = exit_reason;
>> __entry->vcpu_pc = vcpu_pc;
>> ),
>>
>> - TP_printk("PC: 0x%08lx", __entry->vcpu_pc)
>> + TP_printk("HSR_EC: 0x%04x, PC: 0x%08lx",
>> + __entry->exit_reason,
>> + __entry->vcpu_pc)
>> );
>>
>> TRACE_EVENT(kvm_guest_fault,
>
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
