1 files changed, 210 insertions, 0 deletions
diff --git a/libnetdata/worker_utilization/worker_utilization.c b/libnetdata/worker_utilization/worker_utilization.c
new file mode 100644
index 00000000..bd3ad60e
--- /dev/null
+++ b/libnetdata/worker_utilization/worker_utilization.c
@@ -0,0 +1,210 @@
+#include "worker_utilization.h"
+
+#define WORKER_IDLE 'I'
+#define WORKER_BUSY 'B'
+
+struct worker_job_type {
+    char name[WORKER_UTILIZATION_MAX_JOB_NAME_LENGTH + 1];
+
+    // statistics controlled variables
+    size_t statistics_last_jobs_started;
+    usec_t statistics_last_busy_time;
+
+    // worker controlled variables
+    volatile size_t worker_jobs_started;
+    volatile usec_t worker_busy_time;
+};
+
+struct worker {
+    pid_t pid;
+    const char *tag;
+    const char *workname;
+    uint32_t workname_hash;
+
+    // statistics controlled variables
+    volatile usec_t statistics_last_checkpoint;
+    size_t statistics_last_jobs_started;
+    usec_t statistics_last_busy_time;
+
+    // the worker controlled variables
+    volatile size_t job_id;
+    volatile size_t jobs_started;
+    volatile usec_t busy_time;
+    volatile usec_t last_action_timestamp;
+    volatile char last_action;
+
+    struct worker_job_type per_job_type[WORKER_UTILIZATION_MAX_JOB_TYPES];
+
+    struct worker *next;
+};
+
+static netdata_mutex_t base_lock = NETDATA_MUTEX_INITIALIZER;
+static struct worker *base = NULL;
+static __thread struct worker *worker = NULL;
+
+void worker_register(const char *workname) {
+    if(unlikely(worker)) return;
+
+    worker = callocz(1, sizeof(struct worker));
+    worker->pid = gettid();
+    worker->tag = strdupz(netdata_thread_tag());
+    worker->workname = strdupz(workname);
+    worker->workname_hash = simple_hash(worker->workname);
+
+    usec_t now = now_realtime_usec();
+    worker->statistics_last_checkpoint = now;
+    worker->last_action_timestamp = now;
+    worker->last_action = WORKER_IDLE;
+
+    netdata_mutex_lock(&base_lock);
+    worker->next = base;
+    base = worker;
+    netdata_mutex_unlock(&base_lock);
+}
+
+void worker_register_job_name(size_t job_id, const char *name) {
+    if(unlikely(!worker)) return;
+
+    if(unlikely(job_id >= WORKER_UTILIZATION_MAX_JOB_TYPES)) {
+        error("WORKER_UTILIZATION: job_id %zu is too big. Max is %zu", job_id, (size_t)(WORKER_UTILIZATION_MAX_JOB_TYPES - 1));
+        return;
+    }
+    if (*worker->per_job_type[job_id].name) {
+        error("WORKER_UTILIZATION: duplicate job registration: worker '%s' job id %zu is '%s', ignoring '%s'", worker->workname, job_id, worker->per_job_type[job_id].name, name);
+        return;
+    }
+
+    strncpy(worker->per_job_type[job_id].name, name, WORKER_UTILIZATION_MAX_JOB_NAME_LENGTH);
+}
+
+void worker_unregister(void) {
+    if(unlikely(!worker)) return;
+
+    netdata_mutex_lock(&base_lock);
+    if(base == worker)
+        base = worker->next;
+    else {
+        struct worker *p;
+        for(p = base; p && p->next && p->next != worker ;p = p->next);
+        if(p && p->next == worker)
+            p->next = worker->next;
+    }
+    netdata_mutex_unlock(&base_lock);
+
+    freez((void *)worker->tag);
+    freez((void *)worker->workname);
+    freez(worker);
+
+    worker = NULL;
+}
+
+static inline void worker_is_idle_with_time(usec_t now) {
+    usec_t delta = now - worker->last_action_timestamp;
+    worker->busy_time += delta;
+    worker->per_job_type[worker->job_id].worker_busy_time += delta;
+
+    // the worker was busy
+    // set it to idle before we set the timestamp
+
+    worker->last_action = WORKER_IDLE;
+    if(likely(worker->last_action_timestamp < now))
+        worker->last_action_timestamp = now;
+}
+
+void worker_is_idle(void) {
+    if(unlikely(!worker)) return;
+    if(unlikely(worker->last_action != WORKER_BUSY)) return;
+
+    worker_is_idle_with_time(now_realtime_usec());
+}
+
+void worker_is_busy(size_t job_id) {
+    if(unlikely(!worker)) return;
+    if(unlikely(job_id >= WORKER_UTILIZATION_MAX_JOB_TYPES))
+        job_id = 0;
+
+    usec_t now = now_realtime_usec();
+
+    if(worker->last_action == WORKER_BUSY)
+        worker_is_idle_with_time(now);
+
+    // the worker was idle
+    // set the timestamp and then set it to busy
+
+    worker->job_id = job_id;
+    worker->per_job_type[job_id].worker_jobs_started++;
+    worker->jobs_started++;
+    worker->last_action_timestamp = now;
+    worker->last_action = WORKER_BUSY;
+}
+
+
+// statistics interface
+
+void workers_foreach(const char *workname, void (*callback)(void *data, pid_t pid, const char *thread_tag, size_t utilization_usec, size_t duration_usec, size_t jobs_started, size_t is_running, const char **job_types_names, size_t *job_types_jobs_started, usec_t *job_types_busy_time), void *data) {
+    netdata_mutex_lock(&base_lock);
+    uint32_t hash = simple_hash(workname);
+    usec_t busy_time, delta;
+    size_t i, jobs_started, jobs_running;
+
+    struct worker *p;
+    for(p = base; p ; p = p->next) {
+        if(hash != p->workname_hash || strcmp(workname, p->workname)) continue;
+
+        usec_t now = now_realtime_usec();
+
+        // find per job type statistics
+        const char *per_job_type_name[WORKER_UTILIZATION_MAX_JOB_TYPES];
+        size_t per_job_type_jobs_started[WORKER_UTILIZATION_MAX_JOB_TYPES];
+        usec_t per_job_type_busy_time[WORKER_UTILIZATION_MAX_JOB_TYPES];
+        for(i  = 0; i < WORKER_UTILIZATION_MAX_JOB_TYPES ;i++) {
+            per_job_type_name[i] = p->per_job_type[i].name;
+
+            size_t tmp_jobs_started = p->per_job_type[i].worker_jobs_started;
+            per_job_type_jobs_started[i] = tmp_jobs_started - p->per_job_type[i].statistics_last_jobs_started;
+            p->per_job_type[i].statistics_last_jobs_started = tmp_jobs_started;
+
+            usec_t tmp_busy_time = p->per_job_type[i].worker_busy_time;
+            per_job_type_busy_time[i] = tmp_busy_time - p->per_job_type[i].statistics_last_busy_time;
+            p->per_job_type[i].statistics_last_busy_time = tmp_busy_time;
+        }
+
+        // get a copy of the worker variables
+        size_t worker_job_id = p->job_id;
+        usec_t worker_busy_time = p->busy_time;
+        size_t worker_jobs_started = p->jobs_started;
+        char worker_last_action = p->last_action;
+        usec_t worker_last_action_timestamp = p->last_action_timestamp;
+
+        delta = now - p->statistics_last_checkpoint;
+        p->statistics_last_checkpoint = now;
+
+        // this is the only variable both the worker thread and the statistics thread are writing
+        // we set this only when the worker is busy, so that the worker will not
+        // accumulate all the busy time, but only the time after the point we collected statistics
+        if(worker_last_action == WORKER_BUSY && p->last_action_timestamp == worker_last_action_timestamp && p->last_action == WORKER_BUSY)
+            p->last_action_timestamp = now;
+
+        // calculate delta busy time
+        busy_time = worker_busy_time - p->statistics_last_busy_time;
+        p->statistics_last_busy_time = worker_busy_time;
+
+        // calculate delta jobs done
+        jobs_started = worker_jobs_started - p->statistics_last_jobs_started;
+        p->statistics_last_jobs_started = worker_jobs_started;
+
+        jobs_running = 0;
+        if(worker_last_action == WORKER_BUSY) {
+            // the worker is still busy with something
+            // let's add that busy time to the reported one
+            usec_t dt = now - worker_last_action_timestamp;
+            busy_time += dt;
+            per_job_type_busy_time[worker_job_id] += dt;
+            jobs_running = 1;
+        }
+
+        callback(data, p->pid, p->tag, busy_time, delta, jobs_started, jobs_running, per_job_type_name, per_job_type_jobs_started, per_job_type_busy_time);
+    }
+
+    netdata_mutex_unlock(&base_lock);
+}