---

yaml --- r: 367221 b: refs/heads/master c: c6ac1e6 h: refs/heads/master i: 367219: 7d6afd3 v: v3
git-mirror · Mar 15, 2013 · c7d9ab9 · c7d9ab9
1 parent 442dad2
commit c7d9ab9
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Showing 2 changed files with 11 additions and 3 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: db59932f62386cdfd8510c27a83118c5e915e9ea
+refs/heads/master: c6ac1e6edacc7e1fb0405d61f95a797c6a712411
diff --git a/trunk/arch/metag/kernel/perf/perf_event.c b/trunk/arch/metag/kernel/perf/perf_event.c
@@ -240,8 +240,10 @@ int metag_pmu_event_set_period(struct perf_event *event,
 	if (left > (s64)metag_pmu->max_period)
 		left = metag_pmu->max_period;
 
-	if (metag_pmu->write)
-		metag_pmu->write(idx, (u64)(-left) & MAX_PERIOD);
+	if (metag_pmu->write) {
+		local64_set(&hwc->prev_count, -(s32)left);
+		metag_pmu->write(idx, -left & MAX_PERIOD);
+	}
 
 	perf_event_update_userpage(event);
 
@@ -651,6 +653,12 @@ static void metag_pmu_enable_counter(struct hw_perf_event *event, int idx)
 		 * set to a specific value that needs preserving.
 		 */
 		tmp |= metag_in32(PERF_COUNT(idx)) & 0x00ffffff;
+	else
+		/*
+		 * Older cores reset the counter on write, so prev_count needs
+		 * resetting too so we can calculate a correct delta.
+		 */
+		local64_set(&event->prev_count, 0);
 
 	metag_out32(tmp, PERF_COUNT(idx));
 unlock: