svn commit: r297700 - stable/10/sys/dev/mpr

[Alexander Motin]

Author: mav
Date: Fri Apr  8 10:00:07 2016
New Revision: 297700
URL: https://svnweb.freebsd.org/changeset/base/297700

Log:
  MFC r266615: Increase taskqueue thread priority from idle to PRIBIO.
  
  Idle priority is not even time-share, so if system is busy in any way,
  those events may never be executed.  Since in some cases system waits
  for events processed by that thread, that may cause deadlocks.

Modified:
  stable/10/sys/dev/mpr/mpr_sas.c

Modified: stable/10/sys/dev/mpr/mpr_sas.c
==============================================================================
--- stable/10/sys/dev/mpr/mpr_sas.c	Fri Apr  8 09:20:46 2016	(r297699)
+++ stable/10/sys/dev/mpr/mpr_sas.c	Fri Apr  8 10:00:07 2016	(r297700)
@@ -769,9 +769,7 @@ mpr_attach_sas(struct mpr_softc *sc)
 	TASK_INIT(&sassc->ev_task, 0, mprsas_firmware_event_work, sc);
 	sassc->ev_tq = taskqueue_create("mpr_taskq", M_NOWAIT | M_ZERO,
 	    taskqueue_thread_enqueue, &sassc->ev_tq);
-
-	/* Run the task queue with lowest priority */
-	taskqueue_start_threads(&sassc->ev_tq, 1, 255, "%s taskq", 
+	taskqueue_start_threads(&sassc->ev_tq, 1, PRIBIO, "%s taskq", 
 	    device_get_nameunit(sc->mpr_dev));
 
 	mpr_lock(sc);