svn commit: r248748 - head/sys/dev/nvme

[Jim Harris]

Author: jimharris
Date: Tue Mar 26 19:58:17 2013
New Revision: 248748
URL: http://svnweb.freebsd.org/changeset/base/248748

Log:
  Add handling for controller fatal status (csts.cfs).
  
  On any I/O timeout, check for csts.cfs==1.  If set, the controller
  is reporting fatal status and we reset the controller immediately,
  rather than trying to abort the timed out command.
  
  This changeset also includes deferring the controller start portion
  of the reset to a separate task.  This ensures we are always performing
  a controller start operation from a consistent context.
  
  Sponsored by:	Intel
  Reviewed by:	carl

Modified:
  head/sys/dev/nvme/nvme_ctrlr.c
  head/sys/dev/nvme/nvme_private.h
  head/sys/dev/nvme/nvme_qpair.c

Modified: head/sys/dev/nvme/nvme_ctrlr.c
==============================================================================
--- head/sys/dev/nvme/nvme_ctrlr.c	Tue Mar 26 19:52:57 2013	(r248747)
+++ head/sys/dev/nvme/nvme_ctrlr.c	Tue Mar 26 19:58:17 2013	(r248748)
@@ -427,7 +427,7 @@ nvme_ctrlr_reset(struct nvme_controller 
 	status = nvme_ctrlr_hw_reset(ctrlr);
 	DELAY(100*1000);
 	if (status == 0)
-		nvme_ctrlr_start(ctrlr);
+		taskqueue_enqueue(ctrlr->taskqueue, &ctrlr->restart_task);
 }
 
 static int
@@ -686,6 +686,14 @@ err:
 }
 
 static void
+nvme_ctrlr_restart_task(void *arg, int pending)
+{
+	struct nvme_controller *ctrlr = arg;
+
+	nvme_ctrlr_start(ctrlr);
+}
+
+static void
 nvme_ctrlr_intx_handler(void *arg)
 {
 	struct nvme_controller *ctrlr = arg;
@@ -864,6 +872,11 @@ intx:
 
 	ctrlr->cdev->si_drv1 = (void *)ctrlr;
 
+	TASK_INIT(&ctrlr->restart_task, 0, nvme_ctrlr_restart_task, ctrlr);
+	ctrlr->taskqueue = taskqueue_create("nvme_taskq", M_WAITOK,
+	    taskqueue_thread_enqueue, &ctrlr->taskqueue);
+	taskqueue_start_threads(&ctrlr->taskqueue, 1, PI_DISK, "nvme taskq");
+
 	return (0);
 }
 
@@ -872,6 +885,8 @@ nvme_ctrlr_destruct(struct nvme_controll
 {
 	int				i;
 
+	taskqueue_free(ctrlr->taskqueue);
+
 	for (i = 0; i < NVME_MAX_NAMESPACES; i++)
 		nvme_ns_destruct(&ctrlr->ns[i]);
 

Modified: head/sys/dev/nvme/nvme_private.h
==============================================================================
--- head/sys/dev/nvme/nvme_private.h	Tue Mar 26 19:52:57 2013	(r248747)
+++ head/sys/dev/nvme/nvme_private.h	Tue Mar 26 19:58:17 2013	(r248748)
@@ -36,6 +36,7 @@
 #include <sys/mutex.h>
 #include <sys/rman.h>
 #include <sys/systm.h>
+#include <sys/taskqueue.h>
 
 #include <vm/uma.h>
 
@@ -236,6 +237,8 @@ struct nvme_controller {
 	uint32_t		ns_identified;
 	uint32_t		queues_created;
 	uint32_t		num_start_attempts;
+	struct task		restart_task;
+	struct taskqueue	*taskqueue;
 
 	/* For shared legacy interrupt. */
 	int			rid;

Modified: head/sys/dev/nvme/nvme_qpair.c
==============================================================================
--- head/sys/dev/nvme/nvme_qpair.c	Tue Mar 26 19:52:57 2013	(r248747)
+++ head/sys/dev/nvme/nvme_qpair.c	Tue Mar 26 19:58:17 2013	(r248748)
@@ -98,7 +98,7 @@ nvme_qpair_construct_tracker(struct nvme
 	bus_dmamap_load(qpair->dma_tag, tr->prp_dma_map, tr->prp,
 	    sizeof(tr->prp), nvme_single_map, &tr->prp_bus_addr, 0);
 
-	callout_init_mtx(&tr->timer, &qpair->lock, 0);
+	callout_init(&tr->timer, 1);
 	tr->cid = cid;
 	tr->qpair = qpair;
 }
@@ -456,8 +456,24 @@ static void
 nvme_timeout(void *arg)
 {
 	struct nvme_tracker	*tr = arg;
+	struct nvme_qpair	*qpair = tr->qpair;
+	struct nvme_controller	*ctrlr = qpair->ctrlr;
+	union csts_register	csts;
 
-	nvme_ctrlr_cmd_abort(tr->qpair->ctrlr, tr->cid, tr->qpair->id,
+	csts.raw = nvme_mmio_read_4(ctrlr, csts);
+	if (csts.bits.cfs == 1) {
+		/*
+		 * The controller is reporting fatal status.  Don't bother
+		 *  trying to abort the timed out command - proceed
+		 *  immediately to a controller-level reset.
+		 */
+		device_printf(ctrlr->dev,
+		    "controller reports fatal status, resetting...\n");
+		nvme_ctrlr_reset(ctrlr);
+		return;
+	}
+
+	nvme_ctrlr_cmd_abort(ctrlr, tr->cid, qpair->id,
 	    nvme_abort_complete, tr);
 }