Re: [PATCH v2 06/13] KVM: x86: Refactor emulate tracepoint to explicitly take context

Paolo Bonzini
2020-03-03T17:29:38Z

On 03/03/20 17:48, Sean Christopherson wrote:
>>> TP_fast_assign(
>>> __entry->csbase = kvm_x86_ops->get_segment_base(vcpu, VCPU_SREG_CS);
>> This seems the only usage of 'vcpu' parameter now; I checked and even
>> after switching to dynamic emulation context allocation we still set
>> ctxt->vcpu in alloc_emulate_ctxt(), can we get rid of 'vcpu' parameter
>> here then (and use ctxt->vcpu instead)?
> Hmm, ya, not sure what I was thinking here.
>

As long as we have one use of vcpu, I'd rather skip this patch and
adjust patch 8 to use "->". Even the other "explicitly take context"
parts are kinda debatable since you still have to do emul_to_vcpu.
Throwing a handful of

- struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
+ struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;

into patch 8 is not bad at all and limits the churn.

Paolo