On Sat, Aug 28, 2021, Peter Zijlstra wrote: > On Fri, Aug 27, 2021 at 05:35:45PM -0700, Sean Christopherson wrote: > > Like Xu (2): > > perf/core: Rework guest callbacks to prepare for static_call support > > perf/core: Use static_call to optimize perf_guest_info_callbacks > > > > Sean Christopherson (11): > > perf: Ensure perf_guest_cbs aren't reloaded between !NULL check and > > deref > > KVM: x86: Register perf callbacks after calling vendor's > > hardware_setup() > > KVM: x86: Register Processor Trace interrupt hook iff PT enabled in > > guest > > perf: Stop pretending that perf can handle multiple guest callbacks > > perf: Force architectures to opt-in to guest callbacks > > KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu > > variable > > KVM: x86: More precisely identify NMI from guest when handling PMI > > KVM: Move x86's perf guest info callbacks to generic KVM > > KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c > > KVM: arm64: Convert to the generic perf callbacks > > KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c / > > pmu.c Argh, sorry, I somehow managed to miss all of your replies. I'll get back to this series next week. Thanks for the quick response! > Lets keep the whole intel_pt crud inside x86... In theory, I like the idea of burying intel_pt inside x86 (and even in Intel+VMX code for the most part), but the actual implementation is a bit gross. Because of the whole "KVM can be a module" thing, either the static call and __static_call_return0 would need to be exported, or a new register/unregister pair would have to be exported. The unregister path would also need its own synchronize_rcu(). In general, I don't love duplicating the logic, but it's not the end of the world. Either way works for me. Paolo or Peter, do either of you have a preference? > --- > Index: linux-2.6/arch/x86/events/core.c > =================================================================== > --- linux-2.6.orig/arch/x86/events/core.c > +++ linux-2.6/arch/x86/events/core.c > @@ -92,7 +92,7 @@ DEFINE_STATIC_CALL_RET0(x86_pmu_guest_ge > > DEFINE_STATIC_CALL_RET0(x86_guest_state, *(perf_guest_cbs->state)); > DEFINE_STATIC_CALL_RET0(x86_guest_get_ip, *(perf_guest_cbs->get_ip)); > -DEFINE_STATIC_CALL_RET0(x86_guest_handle_intel_pt_intr, *(perf_guest_cbs->handle_intel_pt_intr)); > +DEFINE_STATIC_CALL_RET0(x86_guest_handle_intel_pt_intr, unsigned int (*)(void)); FWIW, the param needs to be a raw function, not a function pointer.