Prevent tasks from linking to one CPU when they are scheduled on another

1 files changed, 12 insertions, 15 deletions

diff --git a/litmus/servers.c b/litmus/servers.c
index 7c47e5fdc125..6e622f3bd5a3 100644
--- a/litmus/servers.c
+++ b/litmus/servers.c
@@ -81,17 +81,18 @@ static int completion_timer_arm(server_domain_t* domain, int cpu)
         lt_t now = domain->start_times[cpu];
         server_t *server = domain->linked_servers[cpu];
         lt_t budget_exhausted = now + server->budget;
+        completion_timer_t *timer = &domain->completion_timers[cpu];
 
         /* This happens when someone attempts to call server_run when
          * the server completes. When this happens, we can ignore the request
          * here because completion_timer_fire will re-arm the timer if
          * the server is still running / was run again.
          */
-        if (hrtimer_active(&domain->completion_timers[cpu].timer)) {
+        if (hrtimer_active(&timer->timer)) {
                 TRACE_SUB(server, "cannot arm completion, already active");
                 return 0;
         }
-        if (domain->completion_timers[cpu].armed) {
+        if (timer->armed) {
                 TRACE_SUB(server, "cannot arm completion, waiting for arm");
                 return 0;
         }
@@ -108,10 +109,9 @@ static int completion_timer_arm(server_domain_t* domain, int cpu)
 #endif
                 on_cpu = cpu;
 
+        err = 1;
         if (cpu != smp_processor_id()) {
-                err = hrtimer_start_on(on_cpu,
-                                       &domain->completion_timers[cpu].info,
-                                       &domain->completion_timers[cpu].timer,
+                err = hrtimer_start_on(on_cpu, &timer->info, &timer->timer,
                                        ns_to_ktime(budget_exhausted),
                                        HRTIMER_MODE_ABS_PINNED);
                 if (err) {
@@ -119,23 +119,20 @@ static int completion_timer_arm(server_domain_t* domain, int cpu)
                 } else {
                         TRACE_SUB(server, "success on P%d!", on_cpu);
                 }
-        } else {
-                err = __hrtimer_start_range_ns(&domain->completion_timers[cpu].timer,
+        } else if (atomic_read(&timer->info.state)!= HRTIMER_START_ON_INACTIVE){
+                err = __hrtimer_start_range_ns(&timer->timer,
                                          ns_to_ktime(budget_exhausted),
                                          0 /* delta */,
                                          HRTIMER_MODE_ABS_PINNED,
                                          0 /* no wakeup */);
         }
 
-        if (!err)
-                domain->completion_timers[cpu].armed = 1;
-        else
-                domain->completion_timers[cpu].armed = 0;
+        timer->armed = (err) ? 0 : 1;
 
-        TRACE_SUB(server, "completion 0x%x and %p armed to fire at %llu",
-                  &domain->completion_timers[cpu].timer,
-                  &domain->completion_timers[cpu].timer,
-                  TIME(budget_exhausted));
+        TRACE_SUB(server, "completion 0x%x and %p armed to fire at %llu, err: %d",
+                  &timer->timer,
+                  &timer->timer,
+                  TIME(budget_exhausted), err);
 
         return !err;
 }