Make the aac driver be INTR_MPSAFE. Once the interrupt handler determines

that a command completion happened, all further processing is deferred to
a taskqueue.  The taskqueue itself runs implicetely under Giant, but we
already used a taskqueue for the biodone() processing, so this at least
saves the contesting of Giant in the interrupt handler.

1 files changed, 12 insertions, 36 deletions

diff --git a/sys/dev/aac/aac.c b/sys/dev/aac/aac.c
index b25286e..28bb8a0 100644
--- a/sys/dev/aac/aac.c
+++ b/sys/dev/aac/aac.c
@@ -83,7 +83,6 @@ static int	aac_bio_command(struct aac_softc *sc, struct aac_command **cmp);
 static void	aac_bio_complete(struct aac_command *cm);
 static int	aac_wait_command(struct aac_command *cm, int timeout);
 static void	aac_command_thread(struct aac_softc *sc);
-static void	aac_host_response(struct aac_softc *sc);
 
 /* Command Buffer Management */
 static void	aac_map_command_helper(void *arg, bus_dma_segment_t *segs,
@@ -661,7 +660,8 @@ aac_intr(void *arg)
 
 	/* It's not ok to return here because of races with the previous step */
 	if (reason & AAC_DB_RESPONSE_READY)
-		aac_host_response(sc);
+		/* handle completion processing */
+		taskqueue_enqueue(taskqueue_swi, &sc->aac_task_complete);
 
 	/* controller wants to talk to the log */
 	if (reason & AAC_DB_PRINTF) {
@@ -845,60 +845,36 @@ aac_command_thread(struct aac_softc *sc)
 }
 
 /*
- * Handle notification of one or more FIBs completed by the controller
+ * Process completed commands.
  */
 static void
-aac_host_response(struct aac_softc *sc)
+aac_complete(void *context, int pending)
 {
+	struct aac_softc *sc;
 	struct aac_command *cm;
 	struct aac_fib *fib;
 	u_int32_t fib_size;
 
 	debug_called(2);
 
+	sc = (struct aac_softc *)context;
+
+	/* pull completed commands off the queue */
 	for (;;) {
 		/* look for completed FIBs on our queue */
 		if (aac_dequeue_fib(sc, AAC_HOST_NORM_RESP_QUEUE, &fib_size,
 				    &fib))
 			break;	/* nothing to do */
-	
+
 		/* get the command, unmap and queue for later processing */
 		cm = (struct aac_command *)fib->Header.SenderData;
 		if (cm == NULL) {
 			AAC_PRINT_FIB(sc, fib);
-		} else {
-			aac_remove_busy(cm);
-			aac_unmap_command(cm);		/* XXX defer? */
-			aac_enqueue_complete(cm);
+			break;
 		}
-	}
-
-	/* handle completion processing */
-#if __FreeBSD_version >= 500005
-	taskqueue_enqueue(taskqueue_swi, &sc->aac_task_complete);
-#else
-	aac_complete(sc, 0);
-#endif
-}
 
-/*
- * Process completed commands.
- */
-static void
-aac_complete(void *context, int pending)
-{
-	struct aac_softc *sc;
-	struct aac_command *cm;
-	
-	debug_called(2);
-
-	sc = (struct aac_softc *)context;
-
-	/* pull completed commands off the queue */
-	for (;;) {
-		cm = aac_dequeue_complete(sc);
-		if (cm == NULL)
-			break;
+		aac_remove_busy(cm);
+		aac_unmap_command(cm);		/* XXX defer? */
 		cm->cm_flags |= AAC_CMD_COMPLETED;
 
 		/* is there a completion handler? */