vmm: Remove the per-vm cookie argument from vmmops taking a vcpu.

[jhb]

Summary

This requires storing a reference the per-vm cookie in the
CPU-specific vCPU structure. Take advantage of this new field to
remove no-longer-needed function arguments in the CPU-specific
backends. In particular, stop passing the per-vm cookie to functions
that either don't use it or only use it for KTR traces.

[corvink]

sys/amd64/vmm/amd/svm.c

286

Why do we keep sc fore this function?

[jhb]

sys/amd64/vmm/amd/svm.c

286

At this stage in the patches sc is still used below to get to sc->vm for vm_set_tsc_offset. Later in the series it does get removed once VCPU_CTR1 and vm_set_tsc_offset no longer need it (D37162)

[corvink]

sys/amd64/vmm/amd/svm.c

286

A few lines below, you're removing sc from svm_set_intercept. VCPU_CTR3 is called there with vcpu->sc-vm. Many other functions get patched the same way here.

[jhb]

sys/amd64/vmm/amd/svm.c

286

I think the strategy I followed was "remove the function arguments other than struct vcpu once all non-KTR-related bits stopped using it". So in this case it is about vm_set_tsc_offset and waiting until it changes. I mostly followed this strategy just to make it a series of changes vs one giant change. That said, it doesn't really matter when it changes within the series.