Hi Eric, Thanks for having a look! On 12/14/20 1:48 PM, Auger Eric wrote: > Alexandru, > > On 12/1/20 4:01 PM, Alexandru Elisei wrote: >> KVM_ARM_VCPU_INIT ioctl calls kvm_reset_vcpu(), which in turn resets the >> PMU with a call to kvm_pmu_vcpu_reset(). The function zeroes the PMU >> chained counters bitmap and stops all the counters with a perf event >> attached. Because it is called before the VCPU has had the chance to run, >> no perf events are in use and none are released. >> >> kvm_arm_pmu_v3_enable(), called by kvm_vcpu_first_run_init() only if the >> VCPU has not been initialized, also resets the PMU. kvm_pmu_vcpu_reset() in > This sounds strange to me. kvm_vcpu_first_run_init() only is called if > kvm_vcpu_initialized(vcpu) is true. Typo on my part, the "not" should not be there. kvm_vcpu_first_run_init() is called only if kvm_vcpu_initialized() returns true in kvm_arch_vcpu_ioctl_run(). >> this case does the exact same thing as the previous call, so remove it. >> >> Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx> >> --- >> arch/arm64/kvm/pmu-emul.c | 2 -- >> 1 file changed, 2 deletions(-) >> >> diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c >> index 398f6df1bbe4..4ad66a532e38 100644 >> --- a/arch/arm64/kvm/pmu-emul.c >> +++ b/arch/arm64/kvm/pmu-emul.c >> @@ -850,8 +850,6 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu) >> return -EINVAL; >> } >> >> - kvm_pmu_vcpu_reset(vcpu); >> - > this patch does not apply for me (vcpu->arch.pmu.ready = true; ?) I should have mentioned it in the cover letter, this is on top of Marc's pmu-undef branch: https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=kvm-arm64/pmu-undef it should work on top of commit 7521c3a9e630 ("KVM: arm64: Get ready of the PMU ready state"), the branch was rebased since I sent the patches. Thanks, Alex > > Thanks > > Eric >> return 0; >> } >> >> _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
