net/smc: Introduce tracepoints for tx and rx msg

This introduce two tracepoints for smc tx and rx msg to help us
diagnosis issues of data path. These two tracepoitns don't cover the
path of CORK or MSG_MORE in tx, just the top half of data path.

Signed-off-by: Tony Lu <tonylu@linux.alibaba.com>
Reviewed-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 45 insertions, 0 deletions

diff --git a/net/smc/smc_rx.c b/net/smc/smc_rx.c
index 170b733bc73675..51e8eb2933ff47 100644
--- a/net/smc/smc_rx.c
+++ b/net/smc/smc_rx.c
@@ -22,6 +22,7 @@
 #include "smc_tx.h" /* smc_tx_consumer_update() */
 #include "smc_rx.h"
 #include "smc_stats.h"
+#include "smc_tracepoint.h"
 
 /* callback implementation to wakeup consumers blocked with smc_rx_wait().
  * indirectly called by smc_cdc_msg_recv_action().
@@ -438,6 +439,8 @@ copy:
 			if (msg && smc_rx_update_consumer(smc, cons, copylen))
 				goto out;
 		}
+
+		trace_smc_rx_recvmsg(smc, copylen);
 	} while (read_remaining);
 out:
 	return read_done;
diff --git a/net/smc/smc_tracepoint.c b/net/smc/smc_tracepoint.c
index 861a416449715c..af031811ddb390 100644
--- a/net/smc/smc_tracepoint.c
+++ b/net/smc/smc_tracepoint.c
@@ -4,3 +4,5 @@
 #include "smc_tracepoint.h"
 
 EXPORT_TRACEPOINT_SYMBOL(smc_switch_to_fallback);
+EXPORT_TRACEPOINT_SYMBOL(smc_tx_sendmsg);
+EXPORT_TRACEPOINT_SYMBOL(smc_rx_recvmsg);
diff --git a/net/smc/smc_tracepoint.h b/net/smc/smc_tracepoint.h
index 3bc97f5f213401..eced1546afaebe 100644
--- a/net/smc/smc_tracepoint.h
+++ b/net/smc/smc_tracepoint.h
@@ -38,6 +38,43 @@ TRACE_EVENT(smc_switch_to_fallback,
 		      __entry->sk, __entry->clcsk, __entry->fallback_rsn)
 );
 
+DECLARE_EVENT_CLASS(smc_msg_event,
+
+		    TP_PROTO(const struct smc_sock *smc, size_t len),
+
+		    TP_ARGS(smc, len),
+
+		    TP_STRUCT__entry(
+				     __field(const void *, smc)
+				     __field(size_t, len)
+				     __string(name, smc->conn.lnk->ibname)
+		    ),
+
+		    TP_fast_assign(
+				   __entry->smc = smc;
+				   __entry->len = len;
+				   __assign_str(name, smc->conn.lnk->ibname);
+		    ),
+
+		    TP_printk("smc=%p len=%zu dev=%s",
+			      __entry->smc, __entry->len,
+			      __get_str(name))
+);
+
+DEFINE_EVENT(smc_msg_event, smc_tx_sendmsg,
+
+	     TP_PROTO(const struct smc_sock *smc, size_t len),
+
+	     TP_ARGS(smc, len)
+);
+
+DEFINE_EVENT(smc_msg_event, smc_rx_recvmsg,
+
+	     TP_PROTO(const struct smc_sock *smc, size_t len),
+
+	     TP_ARGS(smc, len)
+);
+
 #endif /* _TRACE_SMC_H */
 
 #undef TRACE_INCLUDE_PATH
diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c
index 738a4a99c82797..be241d53020f1e 100644
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -28,6 +28,7 @@
 #include "smc_ism.h"
 #include "smc_tx.h"
 #include "smc_stats.h"
+#include "smc_tracepoint.h"
 
 #define SMC_TX_WORK_DELAY	0
 #define SMC_TX_CORK_DELAY	(HZ >> 2)	/* 250 ms */
@@ -245,6 +246,8 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len)
 					   SMC_TX_CORK_DELAY);
 		else
 			smc_tx_sndbuf_nonempty(conn);
+
+		trace_smc_tx_sendmsg(smc, copylen);
 	} /* while (msg_data_left(msg)) */
 
 	return send_done;