From: Shyam Prasad N <sprasad@microsoft.com>
Date: Fri, 21 May 2021 06:35:52 +0000
Subject: [PATCH] cifs: fix string declarations and assignments in tracepoints
Git-commit: eb0688180549e3b72464e9f78df58cb7a5592c7f
References: bsc#1190317
Patch-mainline: v5.13-rc4

We missed using the variable length string macros in several
tracepoints. Fixed them in this change.

There's probably more useful macros that we can use to print
others like flags etc. But I'll submit sepawrate patches for
those at a future date.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: <stable@vger.kernel.org> # v5.12
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
 fs/cifs/trace.h | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

--- a/fs/cifs/trace.h
+++ b/fs/cifs/trace.h
@@ -12,6 +12,11 @@
 
 #include <linux/tracepoint.h>
 
+/*
+ * Please use this 3-part article as a reference for writing new tracepoints:
+ * https://lwn.net/Articles/379903/
+ */
+
 /* For logging errors in read or write */
 DECLARE_EVENT_CLASS(smb3_rw_err_class,
 	TP_PROTO(unsigned int xid,
@@ -526,16 +531,16 @@ DECLARE_EVENT_CLASS(smb3_exit_err_class,
 	TP_ARGS(xid, func_name, rc),
 	TP_STRUCT__entry(
 		__field(unsigned int, xid)
-		__field(const char *, func_name)
+		__string(func_name, func_name)
 		__field(int, rc)
 	),
 	TP_fast_assign(
 		__entry->xid = xid;
-		__entry->func_name = func_name;
+		__assign_str(func_name, func_name);
 		__entry->rc = rc;
 	),
 	TP_printk("\t%s: xid=%u rc=%d",
-		__entry->func_name, __entry->xid, __entry->rc)
+		__get_str(func_name), __entry->xid, __entry->rc)
 )
 
 #define DEFINE_SMB3_EXIT_ERR_EVENT(name)          \
@@ -580,14 +585,14 @@ DECLARE_EVENT_CLASS(smb3_enter_exit_clas
 	TP_ARGS(xid, func_name),
 	TP_STRUCT__entry(
 		__field(unsigned int, xid)
-		__field(const char *, func_name)
+		__string(func_name, func_name)
 	),
 	TP_fast_assign(
 		__entry->xid = xid;
-		__entry->func_name = func_name;
+		__assign_str(func_name, func_name);
 	),
 	TP_printk("\t%s: xid=%u",
-		__entry->func_name, __entry->xid)
+		__get_str(func_name), __entry->xid)
 )
 
 #define DEFINE_SMB3_ENTER_EXIT_EVENT(name)        \
@@ -852,14 +857,14 @@ DECLARE_EVENT_CLASS(smb3_reconnect_class
 	TP_ARGS(currmid, hostname),
 	TP_STRUCT__entry(
 		__field(__u64, currmid)
-		__field(char *, hostname)
+		__string(hostname, hostname)
 	),
 	TP_fast_assign(
 		__entry->currmid = currmid;
-		__entry->hostname = hostname;
+		__assign_str(hostname, hostname);
 	),
 	TP_printk("server=%s current_mid=0x%llx",
-		__entry->hostname,
+		__get_str(hostname),
 		__entry->currmid)
 )
 
@@ -880,18 +885,18 @@ DECLARE_EVENT_CLASS(smb3_credit_class,
 	TP_ARGS(currmid, hostname, credits, credits_to_add),
 	TP_STRUCT__entry(
 		__field(__u64, currmid)
-		__field(char *, hostname)
+		__string(hostname, hostname)
 		__field(int, credits)
 		__field(int, credits_to_add)
 	),
 	TP_fast_assign(
 		__entry->currmid = currmid;
-		__entry->hostname = hostname;
+		__assign_str(hostname, hostname);
 		__entry->credits = credits;
 		__entry->credits_to_add = credits_to_add;
 	),
 	TP_printk("server=%s current_mid=0x%llx credits=%d credits_to_add=%d",
-		__entry->hostname,
+		__get_str(hostname),
 		__entry->currmid,
 		__entry->credits,
 		__entry->credits_to_add)