+static void submit_percent(int cpu_num, int cpu_state, gauge_t percent)
+{
+ value_t value;
+
+ /* This function is called for all known CPU states, but each read
+ * method will only report a subset. The remaining states are left as
+ * NAN and we ignore them here. */
+ if (isnan (percent))
+ return;
+
+ value.gauge = percent;
+ submit_value (cpu_num, cpu_state, "percent", value);
+}
+
+static void submit_derive(int cpu_num, int cpu_state, derive_t derive)
+{
+ value_t value;
+
+ value.derive = derive;
+ submit_value (cpu_num, cpu_state, "cpu", value);
+}
+
+/* Takes the zero-index number of a CPU and makes sure that the module-global
+ * cpu_states buffer is large enough. Returne ENOMEM on erorr. */
+static int cpu_states_alloc (size_t cpu_num) /* {{{ */
+{
+ cpu_state_t *tmp;
+ size_t sz;
+
+ sz = (((size_t) cpu_num) + 1) * COLLECTD_CPU_STATE_MAX;
+ assert (sz > 0);
+
+ /* We already have enough space. */
+ if (cpu_states_num >= sz)
+ return 0;
+
+ tmp = realloc (cpu_states, sz * sizeof (*cpu_states));
+ if (tmp == NULL)
+ {
+ ERROR ("cpu plugin: realloc failed.");
+ return (ENOMEM);
+ }
+ cpu_states = tmp;
+ tmp = cpu_states + cpu_states_num;
+
+ memset (tmp, 0, (sz - cpu_states_num) * sizeof (*cpu_states));
+ cpu_states_num = sz;
+ return 0;
+} /* }}} cpu_states_alloc */
+
+static cpu_state_t *get_cpu_state (size_t cpu_num, size_t state) /* {{{ */
+{
+ size_t index = ((cpu_num * COLLECTD_CPU_STATE_MAX) + state);
+
+ if (index >= cpu_states_num)
+ return (NULL);
+
+ return (&cpu_states[index]);
+} /* }}} cpu_state_t *get_cpu_state */
+
+/* Populates the per-CPU COLLECTD_CPU_STATE_ACTIVE rate and the global rate_by_state
+ * array. */
+static void aggregate (gauge_t *sum_by_state) /* {{{ */
+{
+ size_t cpu_num;
+ size_t state;
+
+ for (state = 0; state < COLLECTD_CPU_STATE_MAX; state++)
+ sum_by_state[state] = NAN;
+
+ for (cpu_num = 0; cpu_num < global_cpu_num; cpu_num++)
+ {
+ cpu_state_t *this_cpu_states = get_cpu_state (cpu_num, 0);
+
+ this_cpu_states[COLLECTD_CPU_STATE_ACTIVE].rate = NAN;
+
+ for (state = 0; state < COLLECTD_CPU_STATE_ACTIVE; state++)
+ {
+ if (!this_cpu_states[state].has_value)
+ continue;
+
+ RATE_ADD (sum_by_state[state], this_cpu_states[state].rate);
+ if (state != COLLECTD_CPU_STATE_IDLE)
+ RATE_ADD (this_cpu_states[COLLECTD_CPU_STATE_ACTIVE].rate, this_cpu_states[state].rate);
+ }
+
+ if (!isnan (this_cpu_states[COLLECTD_CPU_STATE_ACTIVE].rate))
+ this_cpu_states[COLLECTD_CPU_STATE_ACTIVE].has_value = 1;
+
+ RATE_ADD (sum_by_state[COLLECTD_CPU_STATE_ACTIVE], this_cpu_states[COLLECTD_CPU_STATE_ACTIVE].rate);
+ }
+} /* }}} void aggregate */
+
+/* Commits (dispatches) the values for one CPU or the global aggregation.
+ * cpu_num is the index of the CPU to be committed or -1 in case of the global
+ * aggregation. rates is a pointer to COLLECTD_CPU_STATE_MAX gauge_t values holding the
+ * current rate; each rate may be NAN. Calculates the percentage of each state
+ * and dispatches the metric. */
+static void cpu_commit_one (int cpu_num, /* {{{ */
+ gauge_t rates[static COLLECTD_CPU_STATE_MAX])
+{
+ size_t state;
+ gauge_t sum;
+
+ sum = rates[COLLECTD_CPU_STATE_ACTIVE];
+ RATE_ADD (sum, rates[COLLECTD_CPU_STATE_IDLE]);
+
+ if (!report_by_state)
+ {
+ gauge_t percent = 100.0 * rates[COLLECTD_CPU_STATE_ACTIVE] / sum;
+ submit_percent (cpu_num, COLLECTD_CPU_STATE_ACTIVE, percent);
+ return;
+ }
+
+ for (state = 0; state < COLLECTD_CPU_STATE_ACTIVE; state++)
+ {
+ gauge_t percent = 100.0 * rates[state] / sum;
+ submit_percent (cpu_num, state, percent);
+ }
+} /* }}} void cpu_commit_one */
+
+/* Resets the internal aggregation. This is called by the read callback after
+ * each iteration / after each call to cpu_commit(). */
+static void cpu_reset (void) /* {{{ */
+{
+ size_t i;
+
+ for (i = 0; i < cpu_states_num; i++)
+ cpu_states[i].has_value = 0;
+
+ global_cpu_num = 0;
+} /* }}} void cpu_reset */
+
+/* Legacy behavior: Dispatches the raw derive values without any aggregation. */
+static void cpu_commit_without_aggregation (void) /* {{{ */
+{
+ int state;
+
+ for (state = 0; state < COLLECTD_CPU_STATE_ACTIVE; state++)
+ {
+ size_t cpu_num;
+
+ for (cpu_num = 0; cpu_num < global_cpu_num; cpu_num++)
+ {
+ cpu_state_t *s = get_cpu_state (cpu_num, state);
+
+ if (!s->has_value)
+ continue;
+
+ submit_derive ((int) cpu_num, (int) state, s->conv.last_value.derive);
+ }
+ }
+} /* }}} void cpu_commit_without_aggregation */
+
+/* Aggregates the internal state and dispatches the metrics. */
+static void cpu_commit (void) /* {{{ */
+{
+ gauge_t global_rates[COLLECTD_CPU_STATE_MAX] = {
+ NAN, NAN, NAN, NAN, NAN, NAN, NAN, NAN, NAN, NAN /* Batman! */
+ };
+ size_t cpu_num;
+
+ if (report_by_state && report_by_cpu && !report_percent)
+ {
+ cpu_commit_without_aggregation ();
+ return;
+ }
+
+ aggregate (global_rates);
+
+ if (!report_by_cpu)
+ {
+ cpu_commit_one (-1, global_rates);
+ return;
+ }
+
+ for (cpu_num = 0; cpu_num < global_cpu_num; cpu_num++)
+ {
+ cpu_state_t *this_cpu_states = get_cpu_state (cpu_num, 0);
+ gauge_t local_rates[COLLECTD_CPU_STATE_MAX] = {
+ NAN, NAN, NAN, NAN, NAN, NAN, NAN, NAN, NAN, NAN
+ };
+ size_t state;
+
+ for (state = 0; state < COLLECTD_CPU_STATE_MAX; state++)
+ if (this_cpu_states[state].has_value)
+ local_rates[state] = this_cpu_states[state].rate;
+
+ cpu_commit_one ((int) cpu_num, local_rates);
+ }
+} /* }}} void cpu_commit */
+
+/* Adds a derive value to the internal state. This should be used by each read
+ * function for each state. At the end of the iteration, the read function
+ * should call cpu_commit(). */
+static int cpu_stage (size_t cpu_num, size_t state, derive_t value, cdtime_t now) /* {{{ */
+{
+ int status;
+ cpu_state_t *s;
+ value_t v;
+
+ if (state >= COLLECTD_CPU_STATE_ACTIVE)
+ return (EINVAL);
+
+ status = cpu_states_alloc (cpu_num);
+ if (status != 0)
+ return (status);
+
+ if (global_cpu_num <= cpu_num)
+ global_cpu_num = cpu_num + 1;
+
+ s = get_cpu_state (cpu_num, state);
+
+ v.gauge = NAN;
+ status = value_to_rate (&v, value, &s->conv, DS_TYPE_DERIVE, now);
+ if (status != 0)
+ return (status);
+
+ s->rate = v.gauge;
+ s->has_value = 1;
+ return (0);
+} /* }}} int cpu_stage */
+