Latest PEBS rework change could skip initialization
of the ds->pebs_interrupt_threshold for single event
PEBS threshold events.
Making sure the PEBS threshold gets always initialized.
Fixes: 09e61b4f7849 ("perf/x86/intel: Rework the large PEBS setup code")
Signed-off-by: Jiri Olsa <jo...@redhat.com>
---
arch/x86/events/intel/ds.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 248023f54c87..9fe3db5325d1 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -834,14 +834,24 @@ static inline void pebs_update_threshold(struct
cpu_hw_events *cpuc)
static void
pebs_update_state(bool needed_cb, struct cpu_hw_events *cpuc, struct pmu *pmu)
{
+ /*
+ * Make sure we get updated with the first PEBs
+ * event. It'll trigger also during removal, but
+ * that does not hurt.
+ */
+ bool update = cpuc->n_pebs == 1;
+
if (needed_cb != pebs_needs_sched_cb(cpuc)) {
if (!needed_cb)
perf_sched_cb_inc(pmu);
else
perf_sched_cb_dec(pmu);
- pebs_update_threshold(cpuc);
+ update = true;
}
+
+ if (update)
+ pebs_update_threshold(cpuc);
}
void intel_pmu_pebs_add(struct perf_event *event)
--
2.7.4
