static int num_cpu;
-struct thread_data {
+struct cpu_data_t {
value_to_rate_state_t time_state[MAX_AVAIL_FREQS];
- long long transition_prev;
-} * t_data;
+} * cpu_data;
-/* Flags denoting capability of reporting stats. */
-unsigned report_time_in_state, report_total_trans;
+/* Flags denoting capability of reporting CPU frequency statistics. */
+static bool report_p_stats = false;
-static int counter_init(void) {
- t_data = calloc(num_cpu, sizeof(struct thread_data));
- if (t_data == NULL)
- return 0;
+static void cpufreq_stats_init(void) {
+ cpu_data = calloc(num_cpu, sizeof(struct cpu_data_t));
+ if (cpu_data == NULL)
+ return;
- report_time_in_state = 1;
- report_total_trans = 1;
+ report_p_stats = true;
/* Check for stats module and disable if not present. */
for (int i = 0; i < num_cpu; i++) {
- char filename[256];
- int status;
- status = snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/"
- "stats/time_in_state",
- num_cpu);
- if ((status < 1) || ((unsigned int)status >= sizeof(filename)))
- report_time_in_state = 0;
+ char filename[PATH_MAX];
- status = snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/"
- "stats/total_transitions",
- num_cpu);
- if ((status < 1) || ((unsigned int)status >= sizeof(filename)))
- report_total_trans = 0;
-
- /* Initialize total transitions for cpu frequency */
- if (report_total_trans) {
- value_t v;
- snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/stats/total_trans", i);
- if (parse_value_file(filename, &v, DS_TYPE_COUNTER) != 0) {
- WARNING("cpufreq plugin: Reading \"%s\" failed.", filename);
- continue;
- }
- t_data[i].transition_prev = v.counter;
+ snprintf(filename, sizeof(filename),
+ "/sys/devices/system/cpu/cpu%d/cpufreq/stats/time_in_state", i);
+ if (access(filename, R_OK)) {
+ NOTICE("cpufreq plugin: File %s not exists or no access. P-State "
+ "statistics will not be reported. Check if `cpufreq-stats' kernel "
+ "module is loaded.",
+ filename);
+ report_p_stats = false;
+ break;
+ }
+
+ snprintf(filename, sizeof(filename),
+ "/sys/devices/system/cpu/cpu%d/cpufreq/stats/total_trans", i);
+ if (access(filename, R_OK)) {
+ NOTICE("cpufreq plugin: File %s not exists or no access. P-State "
+ "statistics will not be reported. Check if `cpufreq-stats' kernel "
+ "module is loaded.",
+ filename);
+ report_p_stats = false;
+ break;
}
}
- return 0;
+ return;
}
static int cpufreq_init(void) {
- int status;
- char filename[256];
+ char filename[PATH_MAX];
num_cpu = 0;
while (1) {
- status = snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/"
- "scaling_cur_freq",
- num_cpu);
+ int status = snprintf(filename, sizeof(filename),
+ "/sys/devices/system/cpu/cpu%d/cpufreq/"
+ "scaling_cur_freq",
+ num_cpu);
if ((status < 1) || ((unsigned int)status >= sizeof(filename)))
break;
}
INFO("cpufreq plugin: Found %d CPU%s", num_cpu, (num_cpu == 1) ? "" : "s");
- counter_init();
+ cpufreq_stats_init();
if (num_cpu == 0)
plugin_unregister_read("cpufreq");
plugin_dispatch_values(&vl);
}
+static void cpufreq_read_stats(int cpu) {
+ char filename[PATH_MAX];
+ /* Read total transitions for cpu frequency */
+ snprintf(filename, sizeof(filename),
+ "/sys/devices/system/cpu/cpu%d/cpufreq/stats/total_trans", cpu);
+
+ value_t v;
+ if (parse_value_file(filename, &v, DS_TYPE_DERIVE) != 0) {
+ ERROR("cpufreq plugin: Reading \"%s\" failed.", filename);
+ return;
+ }
+ cpufreq_submit(cpu, "transitions", NULL, &v);
+
+ /* Determine percentage time in each state for cpu during previous
+ * interval. */
+ snprintf(filename, sizeof(filename),
+ "/sys/devices/system/cpu/cpu%d/cpufreq/stats/time_in_state", cpu);
+
+ FILE *fh = fopen(filename, "r");
+ if (fh == NULL) {
+ ERROR("cpufreq plugin: Reading \"%s\" failed.", filename);
+ return;
+ }
+
+ int state_index = 0;
+ cdtime_t now = cdtime();
+ char buffer[DATA_MAX_NAME_LEN];
+
+ while (fgets(buffer, sizeof(buffer), fh) != NULL) {
+ unsigned int frequency;
+ unsigned long long time;
+
+ /*
+ * State time units is 10ms. To get rate of seconds per second
+ * we have to divide by 100. To get percents we have to multiply it
+ * by 100 back. So, just use parsed value directly.
+ */
+ if (!sscanf(buffer, "%u%llu", &frequency, &time)) {
+ ERROR("cpufreq plugin: Reading \"%s\" failed.", filename);
+ break;
+ }
+
+ char state[DATA_MAX_NAME_LEN];
+ snprintf(state, sizeof(state), "%u", frequency);
+
+ if (state_index >= MAX_AVAIL_FREQS) {
+ NOTICE("cpufreq plugin: Found too many frequency states (%d > %d). "
+ "Plugin needs to be recompiled. Please open a bug report for "
+ "this.",
+ (state_index + 1), MAX_AVAIL_FREQS);
+ break;
+ }
+
+ gauge_t g;
+ if (value_to_rate(&g, (value_t){.derive = time}, DS_TYPE_DERIVE, now,
+ &(cpu_data[cpu].time_state[state_index])) == 0) {
+ /*
+ * Due to some inaccuracy reported value can be a bit greatrer than 100.1.
+ * That produces gaps on charts.
+ */
+ if (g > 100.1)
+ g = 100.1;
+ cpufreq_submit(cpu, "percent", state, &(value_t){.gauge = g});
+ }
+ state_index++;
+ }
+ fclose(fh);
+}
+
static int cpufreq_read(void) {
- for (int i = 0; i < num_cpu; i++) {
+ for (int cpu = 0; cpu < num_cpu; cpu++) {
char filename[PATH_MAX];
- FILE *fh;
- long long t;
- char buffer[DATA_MAX_NAME_LEN];
/* Read cpu frequency */
snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_cur_freq", i);
+ "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_cur_freq", cpu);
value_t v;
if (parse_value_file(filename, &v, DS_TYPE_GAUGE) != 0) {
/* convert kHz to Hz */
v.gauge *= 1000.0;
- cpufreq_submit(i, "cpufreq", NULL, &v);
-
- /* Read total transitions for cpu frequency */
- if (report_total_trans) {
- snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/stats/total_trans", i);
- if (parse_value_file(filename, &v, DS_TYPE_COUNTER) != 0) {
- WARNING("cpufreq plugin: Reading \"%s\" failed.", filename);
- continue;
- }
- counter_t c = counter_diff(t_data[i].transition_prev, v.counter);
- t_data[i].transition_prev = v.counter;
- cpufreq_submit(i, "transitions", NULL, &(value_t){.counter = c});
- }
+ cpufreq_submit(cpu, "cpufreq", NULL, &v);
- /*
- * Determine percentage time in each state for cpu during previous interval.
- */
- if (report_time_in_state) {
- int j = 0;
- char state[DATA_MAX_NAME_LEN], time[DATA_MAX_NAME_LEN];
-
- snprintf(filename, sizeof(filename),
- "/sys/devices/system/cpu/cpu%d/cpufreq/stats/time_in_state", i);
- fh = fopen(filename, "r");
- if (fh == NULL)
- continue;
- while (fgets(buffer, sizeof(buffer), fh) != NULL) {
- if (!sscanf(buffer, "%s%lli", state, &t)) {
- fclose(fh);
- return 0;
- }
- snprintf(time, sizeof(time), "%lli", t);
- if (parse_value(time, &v, DS_TYPE_DERIVE) != 0) {
- WARNING("cpufreq plugin: Reading \"%s\" failed.", filename);
- continue;
- }
- cdtime_t now = cdtime();
- gauge_t g;
- if (j < MAX_AVAIL_FREQS) {
- if (value_to_rate(&g, v, DS_TYPE_DERIVE, now, &t_data[i].time_state[j]) != 0 ){
- continue;
- j++;
- }
- cpufreq_submit(i, "percent", state, &(value_t){.gauge = g});
- }
- j++;
- }
- fclose(fh);
- }
+ if (report_p_stats)
+ cpufreq_read_stats(cpu);
}
return 0;
} /* int cpufreq_read */