1 files changed, 16 insertions, 14 deletions

diff --git a/kernel/sched_cpupri.c b/kernel/sched_cpupri.c
index d014efbf947a..0f052fc674d5 100644
--- a/kernel/sched_cpupri.c
+++ b/kernel/sched_cpupri.c
@@ -127,21 +127,11 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
 
         /*
          * If the cpu was currently mapped to a different value, we
-         * first need to unmap the old value
+         * need to map it to the new value then remove the old value.
+         * Note, we must add the new value first, otherwise we risk the
+         * cpu being cleared from pri_active, and this cpu could be
+         * missed for a push or pull.
          */
-        if (likely(oldpri != CPUPRI_INVALID)) {
-                struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
-
-                spin_lock_irqsave(&vec->lock, flags);
-
-                vec->count--;
-                if (!vec->count)
-                        clear_bit(oldpri, cp->pri_active);
-                cpumask_clear_cpu(cpu, vec->mask);
-
-                spin_unlock_irqrestore(&vec->lock, flags);
-        }
-
         if (likely(newpri != CPUPRI_INVALID)) {
                 struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
 
@@ -154,6 +144,18 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
 
                 spin_unlock_irqrestore(&vec->lock, flags);
         }
+        if (likely(oldpri != CPUPRI_INVALID)) {
+                struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
+
+                spin_lock_irqsave(&vec->lock, flags);
+
+                vec->count--;
+                if (!vec->count)
+                        clear_bit(oldpri, cp->pri_active);
+                cpumask_clear_cpu(cpu, vec->mask);
+
+                spin_unlock_irqrestore(&vec->lock, flags);
+        }
 
         *currpri = newpri;
 }