ext4: fix ext4_fc_stats trace point

ftrace's __print_symbolic() requires that any enum values used in the
symbol to string translation table be wrapped in a TRACE_DEFINE_ENUM
so that the enum value can be decoded from the ftrace ring buffer by
user space tooling.

This patch also fixes few other problems found in this trace point.
e.g. dereferencing structures in TP_printk which should not be done
at any cost.

Also to avoid checkpatch warnings, this patch removes those
whitespaces/tab stops issues.

Cc: [email protected]
Fixes: aa75f4d ("ext4: main fast-commit commit path")
Reported-by: Steven Rostedt <[email protected]>
Signed-off-by: Ritesh Harjani <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Reviewed-by: Steven Rostedt (Google) <[email protected]>
Reviewed-by: Harshad Shirwadkar <[email protected]>
Link: https://lore.kernel.org/r/b4b9691414c35c62e570b723e661c80674169f9a.1647057583.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <[email protected]>

Author: riteshharjani

include/trace/events/ext4.h

@@ -95,6 +95,17 @@ TRACE_DEFINE_ENUM(ES_REFERENCED_B);
 	{ FALLOC_FL_COLLAPSE_RANGE,	"COLLAPSE_RANGE"},	\
 	{ FALLOC_FL_ZERO_RANGE,		"ZERO_RANGE"})
 
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_XATTR);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_CROSS_RENAME);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_JOURNAL_FLAG_CHANGE);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_NOMEM);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_SWAP_BOOT);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_RESIZE);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_RENAME_DIR);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_FALLOC_RANGE);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_INODE_JOURNAL_DATA);
+TRACE_DEFINE_ENUM(EXT4_FC_REASON_MAX);
+
 #define show_fc_reason(reason)						\
 	__print_symbolic(reason,					\
 		{ EXT4_FC_REASON_XATTR,		"XATTR"},		\
@@ -2723,41 +2734,50 @@ TRACE_EVENT(ext4_fc_commit_stop,
 
 #define FC_REASON_NAME_STAT(reason)					\
 	show_fc_reason(reason),						\
-	__entry->sbi->s_fc_stats.fc_ineligible_reason_count[reason]
+	__entry->fc_ineligible_rc[reason]
 
 TRACE_EVENT(ext4_fc_stats,
-	    TP_PROTO(struct super_block *sb),
-
-	    TP_ARGS(sb),
+	TP_PROTO(struct super_block *sb),
 
-	    TP_STRUCT__entry(
-		    __field(dev_t, dev)
-		    __field(struct ext4_sb_info *, sbi)
-		    __field(int, count)
-		    ),
+	TP_ARGS(sb),
 
-	    TP_fast_assign(
-		    __entry->dev = sb->s_dev;
-		    __entry->sbi = EXT4_SB(sb);
-		    ),
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__array(unsigned int, fc_ineligible_rc, EXT4_FC_REASON_MAX)
+		__field(unsigned long, fc_commits)
+		__field(unsigned long, fc_ineligible_commits)
+		__field(unsigned long, fc_numblks)
+	),
 
-	    TP_printk("dev %d:%d fc ineligible reasons:\n"
-		      "%s:%d, %s:%d, %s:%d, %s:%d, %s:%d, %s:%d, %s:%d, %s:%d, %s:%d; "
-		      "num_commits:%ld, ineligible: %ld, numblks: %ld",
-		      MAJOR(__entry->dev), MINOR(__entry->dev),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_XATTR),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_CROSS_RENAME),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_JOURNAL_FLAG_CHANGE),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_NOMEM),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_SWAP_BOOT),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_RESIZE),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_RENAME_DIR),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_FALLOC_RANGE),
-		      FC_REASON_NAME_STAT(EXT4_FC_REASON_INODE_JOURNAL_DATA),
-		      __entry->sbi->s_fc_stats.fc_num_commits,
-		      __entry->sbi->s_fc_stats.fc_ineligible_commits,
-		      __entry->sbi->s_fc_stats.fc_numblks)
+	TP_fast_assign(
+		int i;
 
+		__entry->dev = sb->s_dev;
+		for (i = 0; i < EXT4_FC_REASON_MAX; i++) {
+			__entry->fc_ineligible_rc[i] =
+				EXT4_SB(sb)->s_fc_stats.fc_ineligible_reason_count[i];
+		}
+		__entry->fc_commits = EXT4_SB(sb)->s_fc_stats.fc_num_commits;
+		__entry->fc_ineligible_commits =
+			EXT4_SB(sb)->s_fc_stats.fc_ineligible_commits;
+		__entry->fc_numblks = EXT4_SB(sb)->s_fc_stats.fc_numblks;
+	),
+
+	TP_printk("dev %d,%d fc ineligible reasons:\n"
+		  "%s:%u, %s:%u, %s:%u, %s:%u, %s:%u, %s:%u, %s:%u, %s:%u, %s:%u "
+		  "num_commits:%lu, ineligible: %lu, numblks: %lu",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_XATTR),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_CROSS_RENAME),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_JOURNAL_FLAG_CHANGE),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_NOMEM),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_SWAP_BOOT),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_RESIZE),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_RENAME_DIR),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_FALLOC_RANGE),
+		  FC_REASON_NAME_STAT(EXT4_FC_REASON_INODE_JOURNAL_DATA),
+		  __entry->fc_commits, __entry->fc_ineligible_commits,
+		  __entry->fc_numblks)
 );
 
 #define DEFINE_TRACE_DENTRY_EVENT(__type)				\