cpu plugin: Add `usage_global_rate`.

diff --git a/src/cpu.c b/src/cpu.c
index 3856f41a9811a0d9cd5cc34041e25c93d3e0c654..19c20d418ce8aed20dd1ba0a38774d8c862d066b 100644 (file)
--- a/src/cpu.c
+++ b/src/cpu.c
@@ -429,17 +429,33 @@ static gauge_t usage_active_rate(usage_t u, size_t cpu) {
   return us.has_value ? us.rate : NAN;
 }
 
+static gauge_t usage_global_rate(usage_t u, state_t state) {
+  size_t cpu_num = u.states_num / STATE_MAX;
+  usage_state_t us = {0};
+  for (size_t i = 0; i < cpu_num; i++) {
+    gauge_t rate = usage_rate(u, i, state);
+    if (isnan(rate)) {
+      continue;
+    }
+
+    us.rate += rate;
+    us.has_value = true;
+  }
+
+  return us.has_value ? us.rate : NAN;
+}
+
 __attribute__((unused)) static gauge_t usage_rate(usage_t u, size_t cpu,
                                                   state_t state) {
+  if (state == STATE_ACTIVE) {
+    return usage_active_rate(u, cpu);
+  }
+
   size_t index = (cpu * STATE_MAX) + state;
   if (index >= u.states_num) {
     return NAN;
   }
 
-  if (state == STATE_ACTIVE) {
-    return usage_active_rate(u, cpu);
-  }
-
   usage_state_t us = u.states[index];
   return us.has_value ? us.rate : NAN;
 }

diff --git a/src/cpu_test.c b/src/cpu_test.c
index 6fbae097d9f84b73d07e646d5670e029c70bad03..2140c43926017616c7b0a46f54c956bd8e1693a1 100644 (file)
--- a/src/cpu_test.c
+++ b/src/cpu_test.c
@@ -100,9 +100,48 @@ DEF_TEST(usage_active) {
   return 0;
 }
 
+DEF_TEST(usage_global_rate) {
+  usage_t usage = {0};
+
+  cdtime_t t0 = TIME_T_TO_CDTIME_T(100);
+  derive_t cpu0_t0 = 1000;
+  derive_t cpu1_t0 = 2000;
+
+  usage_init(&usage, t0);
+  usage_record(&usage, 0, STATE_USER, cpu0_t0);
+  usage_record(&usage, 1, STATE_USER, cpu1_t0);
+
+  // Unable to calculate a rate with a single data point.
+  EXPECT_EQ_DOUBLE(NAN, usage_rate(usage, 0, STATE_USER));
+  EXPECT_EQ_DOUBLE(NAN, usage_rate(usage, 1, STATE_USER));
+  EXPECT_EQ_DOUBLE(NAN, usage_global_rate(usage, STATE_USER));
+  EXPECT_EQ_DOUBLE(NAN, usage_global_rate(usage, STATE_ACTIVE));
+
+  cdtime_t t1 = t0 + TIME_T_TO_CDTIME_T(10);
+  derive_t cpu0_t1 = cpu0_t0 + 300;
+  derive_t cpu1_t1 = cpu1_t0 + 700;
+
+  gauge_t want_cpu0_rate = 300.0 / 10.0;
+  gauge_t want_cpu1_rate = 700.0 / 10.0;
+  gauge_t want_global_rate = want_cpu0_rate + want_cpu1_rate;
+
+  usage_init(&usage, t1);
+  usage_record(&usage, 0, STATE_USER, cpu0_t1);
+  usage_record(&usage, 1, STATE_USER, cpu1_t1);
+
+  EXPECT_EQ_DOUBLE(want_cpu0_rate, usage_rate(usage, 0, STATE_USER));
+  EXPECT_EQ_DOUBLE(want_cpu1_rate, usage_rate(usage, 1, STATE_USER));
+  EXPECT_EQ_DOUBLE(want_global_rate, usage_global_rate(usage, STATE_USER));
+  EXPECT_EQ_DOUBLE(want_global_rate, usage_global_rate(usage, STATE_ACTIVE));
+
+  usage_reset(&usage);
+  return 0;
+}
+
 int main(void) {
   RUN_TEST(usage_simple_rate);
   RUN_TEST(usage_active);
+  RUN_TEST(usage_global_rate);
 
   END_TEST;
 }