diff options
Diffstat (limited to 'arch/x86/events/intel/core.c')
| -rw-r--r-- | arch/x86/events/intel/core.c | 39 |
1 files changed, 27 insertions, 12 deletions
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index cb8522290e6a..eb1484c86bb4 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2110,6 +2110,27 @@ again: GLOBAL_STATUS_LBRS_FROZEN); if (!status) goto done; + /* + * In case multiple PEBS events are sampled at the same time, + * it is possible to have GLOBAL_STATUS bit 62 set indicating + * PEBS buffer overflow and also seeing at most 3 PEBS counters + * having their bits set in the status register. This is a sign + * that there was at least one PEBS record pending at the time + * of the PMU interrupt. PEBS counters must only be processed + * via the drain_pebs() calls and not via the regular sample + * processing loop coming after that the function, otherwise + * phony regular samples may be generated in the sampling buffer + * not marked with the EXACT tag. Another possibility is to have + * one PEBS event and at least one non-PEBS event whic hoverflows + * while PEBS has armed. In this case, bit 62 of GLOBAL_STATUS will + * not be set, yet the overflow status bit for the PEBS counter will + * be on Skylake. + * + * To avoid this problem, we systematically ignore the PEBS-enabled + * counters from the GLOBAL_STATUS mask and we always process PEBS + * events via drain_pebs(). + */ + status &= ~cpuc->pebs_enabled; /* * PEBS overflow sets bit 62 in the global status register @@ -2117,15 +2138,6 @@ again: if (__test_and_clear_bit(62, (unsigned long *)&status)) { handled++; x86_pmu.drain_pebs(regs); - /* - * There are cases where, even though, the PEBS ovfl bit is set - * in GLOBAL_OVF_STATUS, the PEBS events may also have their - * overflow bits set for their counters. We must clear them - * here because they have been processed as exact samples in - * the drain_pebs() routine. They must not be processed again - * in the for_each_bit_set() loop for regular samples below. - */ - status &= ~cpuc->pebs_enabled; status &= x86_pmu.intel_ctrl | GLOBAL_STATUS_TRACE_TOPAPMI; } @@ -3164,13 +3176,16 @@ static void intel_pmu_cpu_starting(int cpu) if (x86_pmu.flags & PMU_FL_EXCL_CNTRS) { for_each_cpu(i, topology_sibling_cpumask(cpu)) { + struct cpu_hw_events *sibling; struct intel_excl_cntrs *c; - c = per_cpu(cpu_hw_events, i).excl_cntrs; + sibling = &per_cpu(cpu_hw_events, i); + c = sibling->excl_cntrs; if (c && c->core_id == core_id) { cpuc->kfree_on_online[1] = cpuc->excl_cntrs; cpuc->excl_cntrs = c; - cpuc->excl_thread_id = 1; + if (!sibling->excl_thread_id) + cpuc->excl_thread_id = 1; break; } } @@ -3975,7 +3990,7 @@ __init int intel_pmu_init(void) x86_pmu.num_counters, INTEL_PMC_MAX_GENERIC); x86_pmu.num_counters = INTEL_PMC_MAX_GENERIC; } - x86_pmu.intel_ctrl = (1 << x86_pmu.num_counters) - 1; + x86_pmu.intel_ctrl = (1ULL << x86_pmu.num_counters) - 1; if (x86_pmu.num_counters_fixed > INTEL_PMC_MAX_FIXED) { WARN(1, KERN_ERR "hw perf events fixed %d > max(%d), clipping!", |