[PATCH net-next 6/9] psp: add core tracked stats for deferred key deletion

[Daniel Zahka <daniel.zahka@gmail.com>]

It is useful to keep track of two stats related to deferred key
deletion:

- tx_key_cnt: the number of outstanding tx keys from the hw's
  perspective
- grace_periods: the number of grace periods that core has retired for
  this dev.

Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
---
 Documentation/netlink/specs/psp.yaml | 14 ++++++++++++++
 include/net/psp/types.h              |  4 ++++
 include/uapi/linux/psp.h             |  2 ++
 net/psp/psp_main.c                   |  1 +
 net/psp/psp_nl.c                     |  3 +++
 net/psp/psp_sock.c                   |  9 ++++++++-
 6 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/Documentation/netlink/specs/psp.yaml b/Documentation/netlink/specs/psp.yaml
index f3a57782d2cf..efaf3f61e37a 100644
--- a/Documentation/netlink/specs/psp.yaml
+++ b/Documentation/netlink/specs/psp.yaml
@@ -153,6 +153,18 @@ attribute-sets:
         doc: |
           Number of PSP packets for transmission with errors.
           Device statistic (from the PSP spec).
+      -
+        name: tx-key-cnt
+        type: sint
+        doc: |
+          Current number of TX keys installed on the device.
+          Kernel statistic.
+      -
+        name: grace-periods
+        type: uint
+        doc: |
+          Number of TX key deletion grace periods completed.
+          Kernel statistic.
 
 operations:
   list:
@@ -267,6 +279,8 @@ operations:
             - dev-id
             - key-rotations
             - stale-events
+            - tx-key-cnt
+            - grace-periods
         pre: psp-device-get-locked
         post: psp-device-unlock
       dump:
diff --git a/include/net/psp/types.h b/include/net/psp/types.h
index 280c7fdc713c..d790efd9d4bc 100644
--- a/include/net/psp/types.h
+++ b/include/net/psp/types.h
@@ -67,6 +67,8 @@ struct psp_dev_config {
  * @stats:	statistics maintained by the core
  * @stats.rotations:	See stats attr key-rotations
  * @stats.stales:	See stats attr stale-events
+ * @stats.tx_key_cnt:	See stats attr tx-key-cnt
+ * @stats.grace_periods:	See stats attr grace-periods
  *
  * @rcu:	RCU head for freeing the structure
  */
@@ -98,6 +100,8 @@ struct psp_dev {
 	struct {
 		unsigned long rotations;
 		unsigned long stales;
+		long tx_key_cnt;
+		unsigned long grace_periods;
 	} stats;
 
 	struct rcu_head rcu;
diff --git a/include/uapi/linux/psp.h b/include/uapi/linux/psp.h
index a3a336488dc3..208ab60e2c88 100644
--- a/include/uapi/linux/psp.h
+++ b/include/uapi/linux/psp.h
@@ -58,6 +58,8 @@ enum {
 	PSP_A_STATS_TX_PACKETS,
 	PSP_A_STATS_TX_BYTES,
 	PSP_A_STATS_TX_ERROR,
+	PSP_A_STATS_TX_KEY_CNT,
+	PSP_A_STATS_GRACE_PERIODS,
 
 	__PSP_A_STATS_MAX,
 	PSP_A_STATS_MAX = (__PSP_A_STATS_MAX - 1)
diff --git a/net/psp/psp_main.c b/net/psp/psp_main.c
index 2fb886edc384..4a7b2ffa718e 100644
--- a/net/psp/psp_main.c
+++ b/net/psp/psp_main.c
@@ -215,6 +215,7 @@ static void psp_tx_del_work_fn(struct work_struct *work)
 		}
 
 		psd->tx_grace_active = false;
+		psd->stats.grace_periods++;
 	}
 
 start_grace:
diff --git a/net/psp/psp_nl.c b/net/psp/psp_nl.c
index a540a1e77694..f0006d2e85c8 100644
--- a/net/psp/psp_nl.c
+++ b/net/psp/psp_nl.c
@@ -526,6 +526,9 @@ psp_nl_stats_fill(struct psp_dev *psd, struct sk_buff *rsp,
 	    nla_put_uint(rsp, PSP_A_STATS_KEY_ROTATIONS,
 			 psd->stats.rotations) ||
 	    nla_put_uint(rsp, PSP_A_STATS_STALE_EVENTS, psd->stats.stales) ||
+	    nla_put_sint(rsp, PSP_A_STATS_TX_KEY_CNT, psd->stats.tx_key_cnt) ||
+	    nla_put_uint(rsp, PSP_A_STATS_GRACE_PERIODS,
+			 psd->stats.grace_periods) ||
 	    nla_put_uint(rsp, PSP_A_STATS_RX_PACKETS, stats.rx_packets) ||
 	    nla_put_uint(rsp, PSP_A_STATS_RX_BYTES, stats.rx_bytes) ||
 	    nla_put_uint(rsp, PSP_A_STATS_RX_AUTH_FAIL, stats.rx_auth_fail) ||
diff --git a/net/psp/psp_sock.c b/net/psp/psp_sock.c
index d038da122ebb..bf6d089657b6 100644
--- a/net/psp/psp_sock.c
+++ b/net/psp/psp_sock.c
@@ -80,12 +80,19 @@ static struct psp_assoc *psp_assoc_dummy(struct psp_assoc *pas)
 static int psp_dev_tx_key_add(struct psp_dev *psd, struct psp_assoc *pas,
 			      struct netlink_ext_ack *extack)
 {
-	return psd->ops->tx_key_add(psd, pas, extack);
+	int rc;
+
+	rc = psd->ops->tx_key_add(psd, pas, extack);
+	if (!rc)
+		psd->stats.tx_key_cnt++;
+
+	return rc;
 }
 
 void psp_dev_tx_key_del(struct psp_dev *psd, struct psp_assoc *pas)
 {
 	psd->ops->tx_key_del(psd, pas);
+	psd->stats.tx_key_cnt--;
 }
 
 static bool psp_dev_needs_defer(struct psp_dev *psd)

-- 
2.47.3