3 files changed, 14 insertions, 7 deletions

diff --git a/include/litmus/debug_trace.h b/include/litmus/debug_trace.h
index 48d086d5a44c..1266ac6a760c 100644
--- a/include/litmus/debug_trace.h
+++ b/include/litmus/debug_trace.h
@@ -28,8 +28,11 @@ extern atomic_t __log_seq_no;
                                 TRACE_ARGS,  ## args)
 
 #define TRACE_TASK(t, fmt, args...)                     \
-        TRACE("(%s/%d:%d) " fmt, (t)->comm, (t)->pid,   \
-              (t)->rt_param.job_params.job_no,  ##args)
+        TRACE("(%s/%d:%d) " fmt,                         \
+              t ? (t)->comm : "null",                    \
+              t ? (t)->pid : 0,                          \
+              t ? (t)->rt_param.job_params.job_no : 0,   \
+              ##args)
 
 #define TRACE_CUR(fmt, args...) \
         TRACE_TASK(current, fmt, ## args)
diff --git a/litmus/fdso.c b/litmus/fdso.c
index 709be3cc8992..3749d6beb107 100644
--- a/litmus/fdso.c
+++ b/litmus/fdso.c
@@ -46,6 +46,8 @@ static const struct fdso_ops* fdso_ops[] = {
 
 static int fdso_create(void** obj_ref, obj_type_t type, void* __user config)
 {
+        BUILD_BUG_ON(ARRAY_SIZE(fdso_ops) != MAX_OBJ_TYPE + 1);
+
         if (fdso_ops[type]->create)
                 return fdso_ops[type]->create(obj_ref, type, config);
         else
diff --git a/litmus/sched_pfp.c b/litmus/sched_pfp.c
index a435ed6621cf..fdcf8a41684a 100644
--- a/litmus/sched_pfp.c
+++ b/litmus/sched_pfp.c
@@ -194,7 +194,7 @@ static struct task_struct* pfp_schedule(struct task_struct * prev)
         np          = exists && is_np(pfp->scheduled);
         sleep       = exists && is_completed(pfp->scheduled);
         migrate     = exists && get_partition(pfp->scheduled) != pfp->cpu;
-        preempt     = migrate || fp_preemption_needed(&pfp->ready_queue, prev);
+        preempt     = !blocks && (migrate || fp_preemption_needed(&pfp->ready_queue, prev));
 
         /* If we need to preempt do so.
          * The following checks set resched to 1 in case of special
@@ -1107,8 +1107,10 @@ static void pcp_priority_inheritance(void)
                 fp_set_prio_inh(pfp, blocker, blocked);
         }
 
-        /* check if anything changed */
-        if (fp_higher_prio(fp_prio_peek(&pfp->ready_queue), pfp->scheduled))
+        /* Check if anything changed. If the blocked job is current, then it is
+         * just blocking and hence is going to call the scheduler anyway. */
+        if (blocked != current &&
+            fp_higher_prio(fp_prio_peek(&pfp->ready_queue), pfp->scheduled))
                 preempt(pfp);
 
         raw_spin_unlock_irqrestore(&pfp->slock, flags);
@@ -1219,10 +1221,10 @@ static void pcp_lower_ceiling(struct pcp_semaphore* sem)
 
         TRACE_CUR("PCP released sem %p\n", sem);
 
+        pcp_priority_inheritance();
+
         /* Wake up all ceiling-blocked jobs that now pass the ceiling. */
         pcp_resume_unblocked();
-
-        pcp_priority_inheritance();
 }
 
 static void pcp_update_prio_ceiling(struct pcp_semaphore* sem,