diff options
Diffstat (limited to 'arch/x86/events')
| -rw-r--r-- | arch/x86/events/intel/lbr.c | 13 | ||||
| -rw-r--r-- | arch/x86/events/perf_event.h | 1 |
2 files changed, 13 insertions, 1 deletions
diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index 07b7175fc378..6f814a27416b 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -488,6 +488,8 @@ void intel_pmu_lbr_add(struct perf_event *event) * be 'new'. Conversely, a new event can get installed through the * context switch path for the first time. */ + if (x86_pmu.intel_cap.pebs_baseline && event->attr.precise_ip > 0) + cpuc->lbr_pebs_users++; perf_sched_cb_inc(event->ctx->pmu); if (!cpuc->lbr_users++ && !event->total_time_running) intel_pmu_lbr_reset(); @@ -507,8 +509,11 @@ void intel_pmu_lbr_del(struct perf_event *event) task_ctx->lbr_callstack_users--; } + if (x86_pmu.intel_cap.pebs_baseline && event->attr.precise_ip > 0) + cpuc->lbr_pebs_users--; cpuc->lbr_users--; WARN_ON_ONCE(cpuc->lbr_users < 0); + WARN_ON_ONCE(cpuc->lbr_pebs_users < 0); perf_sched_cb_dec(event->ctx->pmu); } @@ -658,7 +663,13 @@ void intel_pmu_lbr_read(void) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - if (!cpuc->lbr_users) + /* + * Don't read when all LBRs users are using adaptive PEBS. + * + * This could be smarter and actually check the event, + * but this simple approach seems to work for now. + */ + if (!cpuc->lbr_users || cpuc->lbr_users == cpuc->lbr_pebs_users) return; if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_32) diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 2059c143946f..dced91582147 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -233,6 +233,7 @@ struct cpu_hw_events { * Intel LBR bits */ int lbr_users; + int lbr_pebs_users; struct perf_branch_stack lbr_stack; struct perf_branch_entry lbr_entries[MAX_LBR_ENTRIES]; struct er_account *lbr_sel; |