Add a dodgy workaround to do pending softirqs if we detect them upon a runqueue going idle.

1 files changed, 12 insertions, 10 deletions

diff --git a/kernel/sched/MuQSS.c b/kernel/sched/MuQSS.c
index f66a3daffbf8..fe9425574076 100644
--- a/kernel/sched/MuQSS.c
+++ b/kernel/sched/MuQSS.c
@@ -806,7 +806,13 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
 		raw_spin_unlock(&prev->pi_lock);
 	}
 #endif
-	raw_spin_unlock_irq(&rq->lock);
+	rq_unlock(rq);
+
+	/* Dodgy workaround till we figure out where the softirqs are going */
+	if (unlikely(current == rq->idle && local_softirq_pending() && !in_interrupt()))
+		do_softirq_own_stack();
+
+	local_irq_enable();
 }
 
 static inline bool deadline_before(u64 deadline, u64 time)
@@ -2548,7 +2554,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev,
  * past. prev == current is still correct but we need to recalculate this_rq
  * because prev may have moved to another CPU.
  */
-static struct rq *finish_task_switch(struct task_struct *prev)
+static void finish_task_switch(struct task_struct *prev)
 	__releases(rq->lock)
 {
 	struct rq *rq = this_rq();
@@ -2601,7 +2607,6 @@ static struct rq *finish_task_switch(struct task_struct *prev)
 		kprobe_flush_task(prev);
 		put_task_struct(prev);
 	}
-	return rq;
 }
 
 /**
@@ -2609,10 +2614,7 @@ static struct rq *finish_task_switch(struct task_struct *prev)
  * @prev: the thread we just switched away from.
  */
 asmlinkage __visible void schedule_tail(struct task_struct *prev)
-	__releases(rq->lock)
 {
-	struct rq *rq;
-
 	/*
 	 * New tasks start with FORK_PREEMPT_COUNT, see there and
 	 * finish_task_switch() for details.
@@ -2622,7 +2624,7 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
 	 * PREEMPT_COUNT kernels).
 	 */
 
-	rq = finish_task_switch(prev);
+	finish_task_switch(prev);
 	preempt_enable();
 
 	if (current->set_child_tid)
@@ -2632,7 +2634,7 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
 /*
  * context_switch - switch to the new MM and the new thread's register state.
  */
-static __always_inline struct rq *
+static __always_inline void
 context_switch(struct rq *rq, struct task_struct *prev,
 	       struct task_struct *next)
 {
@@ -2672,7 +2674,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
 	switch_to(prev, next, prev);
 	barrier();
 
-	return finish_task_switch(prev);
+	finish_task_switch(prev);
 }
 
 /*
@@ -3846,7 +3848,7 @@ static void __sched notrace __schedule(bool preempt)
 		++*switch_count;
 
 		trace_sched_switch(preempt, prev, next);
-		rq = context_switch(rq, prev, next); /* unlocks the rq */
+		context_switch(rq, prev, next); /* unlocks the rq */
 	} else {
 		check_siblings(rq);
 		rq_unlock_irq(rq);