commit 9eec21bfbe9096141f15c624d3d0c2142121f6cb
author Steve French <stfrench@microsoft.com> Mon Oct 19 18:18:15 2020 -0500
committer Steve French <stfrench@microsoft.com> Tue Oct 20 11:50:42 2020 -0500
tree ccff1a0a2a1dd876da6220d5395d13116a31f517
parent acf96fef46f271642b90aa658ba49e33ae34ddf0

smb3: add dynamic trace point to trace when credits obtained

SMB3 crediting is used for flow control, and it can be useful to
trace for problem determination how many credits were acquired
and for which operation.

Here is an example ("trace-cmd record -e *add_credits"):
cifsd-9522    [010] ....  5995.202712: smb3_add_credits:
	server=localhost current_mid=0x12 credits=373 credits_to_add=10
cifsd-9522    [010] ....  5995.204040: smb3_add_credits:
	server=localhost current_mid=0x15 credits=400 credits_to_add=30

Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/trace.h

diff --git a/fs/cifs/trace.h b/fs/cifs/trace.h
index eef4b08..90e0fab 100644
--- a/fs/cifs/trace.h
+++ b/fs/cifs/trace.h
@@ -878,33 +878,39 @@ DEFINE_SMB3_RECONNECT_EVENT(partial_send_reconnect);
 DECLARE_EVENT_CLASS(smb3_credit_class,
 	TP_PROTO(__u64	currmid,
 		char *hostname,
-		int credits),
-	TP_ARGS(currmid, hostname, credits),
+		int credits,
+		int credits_to_add),
+	TP_ARGS(currmid, hostname, credits, credits_to_add),
 	TP_STRUCT__entry(
 		__field(__u64, currmid)
 		__field(char *, hostname)
 		__field(int, credits)
+		__field(int, credits_to_add)
 	),
 	TP_fast_assign(
 		__entry->currmid = currmid;
 		__entry->hostname = hostname;
 		__entry->credits = credits;
+		__entry->credits_to_add = credits_to_add;
 	),
-	TP_printk("server=%s current_mid=0x%llx credits=%d",
+	TP_printk("server=%s current_mid=0x%llx credits=%d credits_to_add=%d",
 		__entry->hostname,
 		__entry->currmid,
-		__entry->credits)
+		__entry->credits,
+		__entry->credits_to_add)
 )
 
 #define DEFINE_SMB3_CREDIT_EVENT(name)        \
 DEFINE_EVENT(smb3_credit_class, smb3_##name,  \
 	TP_PROTO(__u64	currmid,		\
 		char *hostname,			\
-		int  credits),			\
-	TP_ARGS(currmid, hostname, credits))
+		int  credits,			\
+		int  credits_to_add),		\
+	TP_ARGS(currmid, hostname, credits, credits_to_add))
 
 DEFINE_SMB3_CREDIT_EVENT(reconnect_with_invalid_credits);
 DEFINE_SMB3_CREDIT_EVENT(credit_timeout);
+DEFINE_SMB3_CREDIT_EVENT(add_credits);
 
 #endif /* _CIFS_TRACE_H */