diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 26f83ad477260..8482440946260 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -748,7 +748,7 @@ void x86_pmu_enable_all(int added) } } -static inline int is_x86_event(struct perf_event *event) +int is_x86_event(struct perf_event *event) { int i; diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index b3020243080e9..bc54741516d63 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -4002,8 +4002,12 @@ static int intel_pmu_hw_config(struct perf_event *event) x86_pmu.pebs_aliases(event); } - if (needs_branch_stack(event) && is_sampling_event(event)) - event->hw.flags |= PERF_X86_EVENT_NEEDS_BRANCH_STACK; + if (needs_branch_stack(event)) { + /* Avoid branch stack setup for counting events in SAMPLE READ */ + if (is_sampling_event(event) || + !(event->attr.sample_type & PERF_SAMPLE_READ)) + event->hw.flags |= PERF_X86_EVENT_NEEDS_BRANCH_STACK; + } if (branch_sample_counters(event)) { struct perf_event *leader, *sibling; diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 79ed3ef2dda1e..6e40b55f68da1 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -110,9 +110,16 @@ static inline bool is_topdown_event(struct perf_event *event) return is_metric_event(event) || is_slots_event(event); } +int is_x86_event(struct perf_event *event); + +static inline bool check_leader_group(struct perf_event *leader, int flags) +{ + return is_x86_event(leader) ? !!(leader->hw.flags & flags) : false; +} + static inline bool is_branch_counters_group(struct perf_event *event) { - return event->group_leader->hw.flags & PERF_X86_EVENT_BRANCH_COUNTERS; + return check_leader_group(event->group_leader, PERF_X86_EVENT_BRANCH_COUNTERS); } struct amd_nb {