net/smc: log important pnetid and state change events

Print to system log when SMC links are available or go down, link group
state changes or pnetids are applied to and removed from devices.
The log entries are triggered by either user configuration actions or
adapter activation/deactivation events and are not expected to happen
often. The entries help SMC users to keep track of the SMC link group
status and to detect when actions are needed (like to add replacements
for failed adapters).

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 44 insertions, 3 deletions

diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c
index 50c96e843fab..be03f1260d59 100644
--- a/net/smc/smc_pnet.c
+++ b/net/smc/smc_pnet.c
@@ -110,8 +110,14 @@ static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
 		if (!pnet_name ||
 		    smc_pnet_match(pnetelem->pnet_name, pnet_name)) {
 			list_del(&pnetelem->list);
-			if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev)
+			if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev) {
 				dev_put(pnetelem->ndev);
+				pr_warn_ratelimited("smc: net device %s "
+						    "erased user defined "
+						    "pnetid %.16s\n",
+						    pnetelem->eth_name,
+						    pnetelem->pnet_name);
+			}
 			kfree(pnetelem);
 			rc = 0;
 		}
@@ -130,6 +136,12 @@ static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
 			    (!pnet_name ||
 			     smc_pnet_match(pnet_name,
 					    ibdev->pnetid[ibport]))) {
+				pr_warn_ratelimited("smc: ib device %s ibport "
+						    "%d erased user defined "
+						    "pnetid %.16s\n",
+						    ibdev->ibdev->name,
+						    ibport + 1,
+						    ibdev->pnetid[ibport]);
 				memset(ibdev->pnetid[ibport], 0,
 				       SMC_MAX_PNETID_LEN);
 				ibdev->pnetid_by_user[ibport] = false;
@@ -144,6 +156,10 @@ static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
 		if (smcd_dev->pnetid_by_user &&
 		    (!pnet_name ||
 		     smc_pnet_match(pnet_name, smcd_dev->pnetid))) {
+			pr_warn_ratelimited("smc: smcd device %s "
+					    "erased user defined pnetid "
+					    "%.16s\n", dev_name(&smcd_dev->dev),
+					    smcd_dev->pnetid);
 			memset(smcd_dev->pnetid, 0, SMC_MAX_PNETID_LEN);
 			smcd_dev->pnetid_by_user = false;
 			rc = 0;
@@ -174,6 +190,10 @@ static int smc_pnet_add_by_ndev(struct net_device *ndev)
 			dev_hold(ndev);
 			pnetelem->ndev = ndev;
 			rc = 0;
+			pr_warn_ratelimited("smc: adding net device %s with "
+					    "user defined pnetid %.16s\n",
+					    pnetelem->eth_name,
+					    pnetelem->pnet_name);
 			break;
 		}
 	}
@@ -201,6 +221,10 @@ static int smc_pnet_remove_by_ndev(struct net_device *ndev)
 			dev_put(pnetelem->ndev);
 			pnetelem->ndev = NULL;
 			rc = 0;
+			pr_warn_ratelimited("smc: removing net device %s with "
+					    "user defined pnetid %.16s\n",
+					    pnetelem->eth_name,
+					    pnetelem->pnet_name);
 			break;
 		}
 	}
@@ -357,6 +381,10 @@ static int smc_pnet_add_eth(struct smc_pnettable *pnettable, struct net *net,
 		kfree(new_pe);
 		goto out_put;
 	}
+	if (ndev)
+		pr_warn_ratelimited("smc: net device %s "
+				    "applied user defined pnetid %.16s\n",
+				    new_pe->eth_name, new_pe->pnet_name);
 	return 0;
 
 out_put:
@@ -377,11 +405,24 @@ static int smc_pnet_add_ib(struct smc_pnettable *pnettable, char *ib_name,
 
 	/* try to apply the pnetid to active devices */
 	ib_dev = smc_pnet_find_ib(ib_name);
-	if (ib_dev)
+	if (ib_dev) {
 		ibdev_applied = smc_pnet_apply_ib(ib_dev, ib_port, pnet_name);
+		if (ibdev_applied)
+			pr_warn_ratelimited("smc: ib device %s ibport %d "
+					    "applied user defined pnetid "
+					    "%.16s\n", ib_dev->ibdev->name,
+					    ib_port,
+					    ib_dev->pnetid[ib_port - 1]);
+	}
 	smcd_dev = smc_pnet_find_smcd(ib_name);
-	if (smcd_dev)
+	if (smcd_dev) {
 		smcddev_applied = smc_pnet_apply_smcd(smcd_dev, pnet_name);
+		if (smcddev_applied)
+			pr_warn_ratelimited("smc: smcd device %s "
+					    "applied user defined pnetid "
+					    "%.16s\n", dev_name(&smcd_dev->dev),
+					    smcd_dev->pnetid);
+	}
 	/* Apply fails when a device has a hardware-defined pnetid set, do not
 	 * add a pnet table entry in that case.
 	 */