kcm: Add statistics and proc interfaces

This patch adds various counters for KCM. These include counters for
messages and bytes received or sent, as well as counters for number of
attached/unattached TCP sockets and other error or edge events.

The statistics are exposed via a proc interface. /proc/net/kcm provides
statistics per KCM socket and per psock (attached TCP sockets).
/proc/net/kcm_stats provides aggregate statistics.

Signed-off-by: Tom Herbert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

include/net/kcm.h

@@ -17,6 +17,42 @@
 
 extern unsigned int kcm_net_id;
 
+#define KCM_STATS_ADD(stat, count) ((stat) += (count))
+#define KCM_STATS_INCR(stat) ((stat)++)
+
+struct kcm_psock_stats {
+	unsigned long long rx_msgs;
+	unsigned long long rx_bytes;
+	unsigned long long tx_msgs;
+	unsigned long long tx_bytes;
+	unsigned int rx_aborts;
+	unsigned int rx_mem_fail;
+	unsigned int rx_need_more_hdr;
+	unsigned int rx_bad_hdr_len;
+	unsigned long long reserved;
+	unsigned long long unreserved;
+	unsigned int tx_aborts;
+};
+
+struct kcm_mux_stats {
+	unsigned long long rx_msgs;
+	unsigned long long rx_bytes;
+	unsigned long long tx_msgs;
+	unsigned long long tx_bytes;
+	unsigned int rx_ready_drops;
+	unsigned int tx_retries;
+	unsigned int psock_attach;
+	unsigned int psock_unattach_rsvd;
+	unsigned int psock_unattach;
+};
+
+struct kcm_stats {
+	unsigned long long rx_msgs;
+	unsigned long long rx_bytes;
+	unsigned long long tx_msgs;
+	unsigned long long tx_bytes;
+};
+
 struct kcm_tx_msg {
 	unsigned int sent;
 	unsigned int fragidx;
@@ -41,6 +77,8 @@ struct kcm_sock {
 	u32 done : 1;
 	struct work_struct done_work;
 
+	struct kcm_stats stats;
+
 	/* Transmit */
 	struct kcm_psock *tx_psock;
 	struct work_struct tx_work;
@@ -77,6 +115,8 @@ struct kcm_psock {
 
 	struct list_head psock_list;
 
+	struct kcm_psock_stats stats;
+
 	/* Receive */
 	struct sk_buff *rx_skb_head;
 	struct sk_buff **rx_skb_nextp;
@@ -86,15 +126,21 @@ struct kcm_psock {
 	struct delayed_work rx_delayed_work;
 	struct bpf_prog *bpf_prog;
 	struct kcm_sock *rx_kcm;
+	unsigned long long saved_rx_bytes;
+	unsigned long long saved_rx_msgs;
 
 	/* Transmit */
 	struct kcm_sock *tx_kcm;
 	struct list_head psock_avail_list;
+	unsigned long long saved_tx_bytes;
+	unsigned long long saved_tx_msgs;
 };
 
 /* Per net MUX list */
 struct kcm_net {
 	struct mutex mutex;
+	struct kcm_psock_stats aggregate_psock_stats;
+	struct kcm_mux_stats aggregate_mux_stats;
 	struct list_head mux_list;
 	int count;
 };
@@ -110,6 +156,9 @@ struct kcm_mux {
 	struct list_head psocks;	/* List of all psocks on MUX */
 	int psocks_cnt;		/* Total attached sockets */
 
+	struct kcm_mux_stats stats;
+	struct kcm_psock_stats aggregate_psock_stats;
+
 	/* Receive */
 	spinlock_t rx_lock ____cacheline_aligned_in_smp;
 	struct list_head kcm_rx_waiters; /* KCMs waiting for receiving */
@@ -122,4 +171,49 @@ struct kcm_mux {
 	struct list_head kcm_tx_waiters; /* KCMs waiting for a TX psock */
 };
 
+#ifdef CONFIG_PROC_FS
+int kcm_proc_init(void);
+void kcm_proc_exit(void);
+#else
+static int kcm_proc_init(void) { return 0; }
+static void kcm_proc_exit(void) { }
+#endif
+
+static inline void aggregate_psock_stats(struct kcm_psock_stats *stats,
+					 struct kcm_psock_stats *agg_stats)
+{
+	/* Save psock statistics in the mux when psock is being unattached. */
+
+#define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
+	SAVE_PSOCK_STATS(rx_msgs);
+	SAVE_PSOCK_STATS(rx_bytes);
+	SAVE_PSOCK_STATS(rx_aborts);
+	SAVE_PSOCK_STATS(rx_mem_fail);
+	SAVE_PSOCK_STATS(rx_need_more_hdr);
+	SAVE_PSOCK_STATS(rx_bad_hdr_len);
+	SAVE_PSOCK_STATS(tx_msgs);
+	SAVE_PSOCK_STATS(tx_bytes);
+	SAVE_PSOCK_STATS(reserved);
+	SAVE_PSOCK_STATS(unreserved);
+	SAVE_PSOCK_STATS(tx_aborts);
+#undef SAVE_PSOCK_STATS
+}
+
+static inline void aggregate_mux_stats(struct kcm_mux_stats *stats,
+				       struct kcm_mux_stats *agg_stats)
+{
+	/* Save psock statistics in the mux when psock is being unattached. */
+
+#define SAVE_MUX_STATS(_stat) (agg_stats->_stat += stats->_stat)
+	SAVE_MUX_STATS(rx_msgs);
+	SAVE_MUX_STATS(rx_bytes);
+	SAVE_MUX_STATS(tx_msgs);
+	SAVE_MUX_STATS(tx_bytes);
+	SAVE_MUX_STATS(rx_ready_drops);
+	SAVE_MUX_STATS(psock_attach);
+	SAVE_MUX_STATS(psock_unattach_rsvd);
+	SAVE_MUX_STATS(psock_unattach);
+#undef SAVE_MUX_STATS
+}
+
 #endif /* __NET_KCM_H_ */

net/kcm/Makefile

@@ -1,3 +1,3 @@
 obj-$(CONFIG_AF_KCM) += kcm.o
 
-kcm-y := kcmsock.o
+kcm-y := kcmsock.o kcmproc.o