| Message ID | 20240307011344.835640-3-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: VMX: Disable LBRs if CPU doesn't have callstacks | expand |
On Wed, Mar 06, 2024, Sean Christopherson wrote: > Add a "has_callstack" field to the x86_pmu_lbr structure used to pass > information to KVM, and set it accordingly in x86_perf_get_lbr(). KVM > will use has_callstack to avoid trying to create perf LBR events with > PERF_SAMPLE_BRANCH_CALL_STACK on CPUs that don't support callstacks. > > Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Mingwei Zhang <mizhang@google.com> > --- > arch/x86/events/intel/lbr.c | 1 + > arch/x86/include/asm/perf_event.h | 1 + > 2 files changed, 2 insertions(+) > > diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c > index 78cd5084104e..4367aa77cb8d 100644 > --- a/arch/x86/events/intel/lbr.c > +++ b/arch/x86/events/intel/lbr.c > @@ -1693,6 +1693,7 @@ void x86_perf_get_lbr(struct x86_pmu_lbr *lbr) > lbr->from = x86_pmu.lbr_from; > lbr->to = x86_pmu.lbr_to; > lbr->info = x86_pmu.lbr_info; > + lbr->has_callstack = x86_pmu_has_lbr_callstack(); > } > EXPORT_SYMBOL_GPL(x86_perf_get_lbr); > > diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h > index 3736b8a46c04..7f1e17250546 100644 > --- a/arch/x86/include/asm/perf_event.h > +++ b/arch/x86/include/asm/perf_event.h > @@ -555,6 +555,7 @@ struct x86_pmu_lbr { > unsigned int from; > unsigned int to; > unsigned int info; > + bool has_callstack; > }; > > extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap); > -- > 2.44.0.278.ge034bb2e1d-goog >
diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index 78cd5084104e..4367aa77cb8d 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -1693,6 +1693,7 @@ void x86_perf_get_lbr(struct x86_pmu_lbr *lbr) lbr->from = x86_pmu.lbr_from; lbr->to = x86_pmu.lbr_to; lbr->info = x86_pmu.lbr_info; + lbr->has_callstack = x86_pmu_has_lbr_callstack(); } EXPORT_SYMBOL_GPL(x86_perf_get_lbr); diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index 3736b8a46c04..7f1e17250546 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -555,6 +555,7 @@ struct x86_pmu_lbr { unsigned int from; unsigned int to; unsigned int info; + bool has_callstack; }; extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
Add a "has_callstack" field to the x86_pmu_lbr structure used to pass information to KVM, and set it accordingly in x86_perf_get_lbr(). KVM will use has_callstack to avoid trying to create perf LBR events with PERF_SAMPLE_BRANCH_CALL_STACK on CPUs that don't support callstacks. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/events/intel/lbr.c | 1 + arch/x86/include/asm/perf_event.h | 1 + 2 files changed, 2 insertions(+)