st-job-stats: output number of preemptions and migrations

1 files changed, 59 insertions, 19 deletions

diff --git a/src/job_stats.c b/src/job_stats.c
index 156be60..f1406f4 100644
--- a/src/job_stats.c
+++ b/src/job_stats.c
@@ -17,43 +17,81 @@ static double nano_to_ms(int64_t ns)
         return ns * 1E-6;
 }
 
+static void count_preemptions(
+        struct evlink *release,
+        struct evlink *completion,
+        unsigned int *preemptions,
+        unsigned int *migrations)
+{
+        struct evlink *e;
+        int seen_switched_away = 0;
+        u8 last_cpu = 0;
+
+        for (e = release; e != completion; e = e->next) {
+                if (e->rec->hdr.job == release->rec->hdr.job) {
+                        switch (e->rec->hdr.type) {
+                                case ST_SWITCH_AWAY:
+                                        seen_switched_away = 1;
+                                        last_cpu = e->rec->hdr.cpu;
+                                        break;
+                                case ST_SWITCH_TO:
+                                        if (seen_switched_away)
+                                                (*preemptions)++;
+                                        if (seen_switched_away &&
+                                                e->rec->hdr.cpu != last_cpu)
+                                                (*migrations)++;
+                                        break;
+                                default:
+                                        break;
+                        }
+                }
+        }
+}
+
 static void print_stats(
         struct task* t,
-        struct st_event_record *release,
-        struct st_event_record *completion)
+        struct evlink *release,
+        struct evlink *completion)
 {
         int64_t lateness;
         u64 response;
+        unsigned int preemptions = 0, migrations = 0;
+
+        lateness  = completion->rec->data.completion.when;
+        lateness -= release->rec->data.release.deadline;
+        response  = completion->rec->data.completion.when;
+        response -= release->rec->data.release.release;
 
-        lateness  = completion->data.completion.when;
-        lateness -= release->data.release.deadline;
-        response  = completion->data.completion.when;
-        response -= release->data.release.release;
+        count_preemptions(release, completion, &preemptions, &migrations);
 
         if (want_ms)
                 printf(" %5u, %5u, %10.2f, %10.2f, %8d, %10.2f, %10.2f, %7d"
-                        ", %10.2f\n",
-                       release->hdr.pid,
-                       release->hdr.job,
+                        ", %10.2f, %12u, %12u\n",
+                       release->rec->hdr.pid,
+                       release->rec->hdr.job,
                        nano_to_ms(per(t)),
                        nano_to_ms(response),
                        lateness > 0,
                        nano_to_ms(lateness),
                        lateness > 0 ? nano_to_ms(lateness) : 0,
-                       completion->data.completion.forced,
-                       nano_to_ms(completion->data.completion.exec_time));
+                       completion->rec->data.completion.forced,
+                       nano_to_ms(completion->rec->data.completion.exec_time),
+                       preemptions,
+                       migrations);
         else
                 printf(" %5u, %5u, %10llu, %10llu, %8d, %10lld, %10lld, %7d"
-                        ", %10llu\n",
-                       release->hdr.pid,
-                       release->hdr.job,
+                        ", %10llu, %12u, %12u\n",
+                       release->rec->hdr.pid,
+                       release->rec->hdr.job,
                        (unsigned long long) per(t),
                        (unsigned long long) response,
                        lateness > 0,
                        (long long) lateness,
                        lateness > 0 ? (long long) lateness : 0,
-                       completion->data.completion.forced,
-                       (unsigned long long) completion->data.completion.exec_time);
+                       completion->rec->data.completion.forced,
+                       (unsigned long long) completion->rec->data.completion.exec_time,
+                       preemptions,
+                       migrations);
 }
 
 static void print_task_info(struct task *t)
@@ -173,7 +211,7 @@ int main(int argc, char** argv)
         }
 
         /* print header */
-        printf("#%5s, %5s, %10s, %10s, %8s, %10s, %10s, %7s, %10s\n",
+        printf("#%5s, %5s, %10s, %10s, %8s, %10s, %10s, %7s, %10s, %12s, %12s\n",
                "Task",
                "Job",
                "Period",
@@ -182,7 +220,9 @@ int main(int argc, char** argv)
                "Lateness",
                "Tardiness",
                "Forced?",
-               "ACET");
+               "ACET",
+               "Preemptions",
+               "Migrations");
 
         /* print stats for each task */
         for_each_task(t) {
@@ -204,7 +244,7 @@ int main(int argc, char** argv)
                                 while (pos && count < MAX_COMPLETIONS_TO_CHECK) {
                                         find(pos, ST_COMPLETION);
                                         if (pos->rec->hdr.job == rec->hdr.job) {
-                                                print_stats(t, rec, pos->rec);
+                                                print_stats(t, e, pos);
                                                 break;
                                         } else {
                                                 pos = pos->next;