[ANNOUNCE] v5.0.21-rt16

[ANNOUNCE] v5.0.21-rt16

[Sebastian Andrzej Siewior]

Dear RT folks!

I'm pleased to announce the v5.0.21-rt16 patch set. 

Changes since v5.0.21-rt15:

  - Do not invoke softirq if ksoftirqd has been scheduled. This change
    aligns softirq handling closer with mainline. A busy network driver
    will now handover further processing to ksoftirqd. This wasn't the
    case since the recent softirq rework.

Known issues
     - rcutorture is currently broken on -RT. Reported by Juri Lelli.

The delta patch against v5.0.21-rt15 is appended below and can be found here:
 
     https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.0/incr/patch-5.0.21-rt15-rt16.patch.xz

You can get this release via the git tree at:

    git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v5.0.21-rt16

The RT patch against v5.0.21 can be found here:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.0/older/patch-5.0.21-rt16.patch.xz

The split quilt queue is available at:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.0/older/patches-5.0.21-rt16.tar.xz

Sebastian

diff --git a/kernel/softirq.c b/kernel/softirq.c
index c4fae96f23c54..dc31f1b4ee217 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -78,7 +78,6 @@ static void wakeup_softirqd(void)
 		wake_up_process(tsk);
 }
 
-#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * If ksoftirqd is scheduled, we do not want to process pending softirqs
  * right now. Let ksoftirqd handle this at its own rate, to get fairness,
@@ -93,7 +92,6 @@ static bool ksoftirqd_running(unsigned long pending)
 		return false;
 	return tsk && (tsk->state == TASK_RUNNING);
 }
-#endif
 
 /*
  * preempt_count and SOFTIRQ_OFFSET usage:
@@ -173,7 +171,7 @@ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
 
 	if (unlikely(count == 1)) {
 		pending = local_softirq_pending();
-		if (pending) {
+		if (pending && !ksoftirqd_running(pending)) {
 			if (!in_atomic())
 				__do_softirq();
 			else
diff --git a/localversion-rt b/localversion-rt
index 18777ec0c27d4..1199ebade17b4 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt15
+-rt16