[PATCH] nvme: improve logging

[hare@suse.de (Hannes Reinecke)]

Currently nvme is very reluctant if it comes to logging anything,
_unless_ it's an ANA AEN. So this patch tries to remedy this by
decreasing the priority for the ANA AEN logging message, and improve
the logging when calling nvme_reset_ctrl().

Signed-off-by: Hannes Reinecke <hare at suse.com>
---
 drivers/nvme/host/core.c      | 44 +++++++++++++++++++++++++++++--------------
 drivers/nvme/host/multipath.c |  5 ++++-
 2 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 8d285bfcd352..98260b2c7a6f 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -94,6 +94,24 @@ static void nvme_put_subsystem(struct nvme_subsystem *subsys);
 static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
 					   unsigned nsid);
 
+static const char *nvme_ctrl_state_name(struct nvme_ctrl *ctrl)
+{
+	static const char *const state_name[] = {
+		[NVME_CTRL_NEW]		= "new",
+		[NVME_CTRL_LIVE]	= "live",
+		[NVME_CTRL_ADMIN_ONLY]	= "only-admin",
+		[NVME_CTRL_RESETTING]	= "resetting",
+		[NVME_CTRL_CONNECTING]	= "connecting",
+		[NVME_CTRL_DELETING]	= "deleting",
+		[NVME_CTRL_DEAD]	= "dead",
+	};
+
+	if ((unsigned)ctrl->state < ARRAY_SIZE(state_name) &&
+	    state_name[ctrl->state])
+		return state_name[ctrl->state];
+	return NULL;
+}
+
 static void nvme_set_queue_dying(struct nvme_ns *ns)
 {
 	/*
@@ -119,10 +137,17 @@ static void nvme_queue_scan(struct nvme_ctrl *ctrl)
 
 int nvme_reset_ctrl(struct nvme_ctrl *ctrl)
 {
-	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING))
+	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING)) {
+		const char *state_name = nvme_ctrl_state_name(ctrl);
+
+		dev_warn(ctrl->device, "cannot reset ctrl in state %s\n",
+			 state_name ? state_name : "unknown");
 		return -EBUSY;
-	if (!queue_work(nvme_reset_wq, &ctrl->reset_work))
+	}
+	if (!queue_work(nvme_reset_wq, &ctrl->reset_work)) {
+		dev_dbg(ctrl->device, "ctrl reset already queued\n");
 		return -EBUSY;
+	}
 	return 0;
 }
 EXPORT_SYMBOL_GPL(nvme_reset_ctrl);
@@ -2971,19 +2996,10 @@ static ssize_t nvme_sysfs_show_state(struct device *dev,
 				     char *buf)
 {
 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
-	static const char *const state_name[] = {
-		[NVME_CTRL_NEW]		= "new",
-		[NVME_CTRL_LIVE]	= "live",
-		[NVME_CTRL_ADMIN_ONLY]	= "only-admin",
-		[NVME_CTRL_RESETTING]	= "resetting",
-		[NVME_CTRL_CONNECTING]	= "connecting",
-		[NVME_CTRL_DELETING]	= "deleting",
-		[NVME_CTRL_DEAD]	= "dead",
-	};
+	const char *state_name = nvme_ctrl_state_name(ctrl);
 
-	if ((unsigned)ctrl->state < ARRAY_SIZE(state_name) &&
-	    state_name[ctrl->state])
-		return sprintf(buf, "%s\n", state_name[ctrl->state]);
+	if (state_name)
+		return sprintf(buf, "%s\n", state_name);
 
 	return sprintf(buf, "unknown state\n");
 }
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 503539d4616a..cca60044163b 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -81,6 +81,9 @@ void nvme_failover_req(struct request *req)
 		 * Reset the controller for any non-ANA error as we don't know
 		 * what caused the error.
 		 */
+		dev_info(ns->ctrl->device,
+			"nvme status 0x%04x, resetting controller\n",
+			status);
 		nvme_reset_ctrl(ns->ctrl);
 		break;
 	}
@@ -423,7 +426,7 @@ static int nvme_update_ana_state(struct nvme_ctrl *ctrl,
 	unsigned *nr_change_groups = data;
 	struct nvme_ns *ns;
 
-	dev_info(ctrl->device, "ANA group %d: %s.\n",
+	dev_dbg(ctrl->device, "ANA group %d: %s.\n",
 			le32_to_cpu(desc->grpid),
 			nvme_ana_state_names[desc->state]);
 
-- 
2.16.4