2 files changed, 27 insertions, 0 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index e45332d08a58..dbdcca43cac6 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -659,6 +659,28 @@ void perf_evsel__delete(struct perf_evsel *evsel)
         free(evsel);
 }
 
+static inline void compute_deltas(struct perf_evsel *evsel,
+                                  int cpu,
+                                  struct perf_counts_values *count)
+{
+        struct perf_counts_values tmp;
+
+        if (!evsel->prev_raw_counts)
+                return;
+
+        if (cpu == -1) {
+                tmp = evsel->prev_raw_counts->aggr;
+                evsel->prev_raw_counts->aggr = *count;
+        } else {
+                tmp = evsel->prev_raw_counts->cpu[cpu];
+                evsel->prev_raw_counts->cpu[cpu] = *count;
+        }
+
+        count->val = count->val - tmp.val;
+        count->ena = count->ena - tmp.ena;
+        count->run = count->run - tmp.run;
+}
+
 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
                               int cpu, int thread, bool scale)
 {
@@ -674,6 +696,8 @@ int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
         if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
                 return -errno;
 
+        compute_deltas(evsel, cpu, &count);
+
         if (scale) {
                 if (count.run == 0)
                         count.val = 0;
@@ -712,6 +736,8 @@ int __perf_evsel__read(struct perf_evsel *evsel,
                 }
         }
 
+        compute_deltas(evsel, -1, aggr);
+
         evsel->counts->scaled = 0;
         if (scale) {
                 if (aggr->run == 0) {
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index c68d1b82e843..3a4cd60044ea 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -53,6 +53,7 @@ struct perf_evsel {
         struct xyarray          *sample_id;
         u64                     *id;
         struct perf_counts      *counts;
+        struct perf_counts      *prev_raw_counts;
         int                     idx;
         u32                     ids;
         struct hists            hists;