[PATCH] Trace: add __print_symbolic_u64 to avoid warnings on 32bit machine

[liubo <liubo2009@cn.fujitsu.com>]

Btrfs has some "ULL" macros, and when these macros are passed to tracepoints'
__print_symbolic(), there will be 64->32 truncate WARNINGS during compiling
on 32bit box.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
---
 include/linux/ftrace_event.h |   12 ++++++++++++
 include/trace/events/btrfs.h |    4 ++--
 include/trace/ftrace.h       |   13 +++++++++++++
 kernel/trace/trace_output.c  |   27 +++++++++++++++++++++++++++
 4 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 22b32af..6b2e245 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -16,6 +16,11 @@ struct trace_print_flags {
 	const char		*name;
 };
 
+struct trace_print_flags_u64 {
+	unsigned long long	mask;
+	const char		*name;
+};
+
 const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 				   unsigned long flags,
 				   const struct trace_print_flags *flag_array);
@@ -23,6 +28,13 @@ const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 				     const struct trace_print_flags *symbol_array);
 
+#if BITS_PER_LONG == 32
+const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
+					 unsigned long long val,
+					 const struct trace_print_flags_u64
+								 *symbol_array);
+#endif
+
 const char *ftrace_print_hex_seq(struct trace_seq *p,
 				 const unsigned char *buf, int len);
 
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index f445cff..4114129 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -28,7 +28,7 @@ struct extent_buffer;
 		{ BTRFS_SHARED_DATA_REF_KEY, 	"SHARED_DATA_REF" })
 
 #define __show_root_type(obj)						\
-	__print_symbolic(obj,						\
+	__print_symbolic_u64(obj,					\
 		{ BTRFS_ROOT_TREE_OBJECTID, 	"ROOT_TREE"	},	\
 		{ BTRFS_EXTENT_TREE_OBJECTID, 	"EXTENT_TREE"	},	\
 		{ BTRFS_CHUNK_TREE_OBJECTID, 	"CHUNK_TREE"	},	\
@@ -125,7 +125,7 @@ DEFINE_EVENT(btrfs__inode, btrfs_inode_evict,
 );
 
 #define __show_map_type(type)						\
-	__print_symbolic(type,						\
+	__print_symbolic_u64(type,					\
 		{ EXTENT_MAP_LAST_BYTE, "LAST_BYTE" 	},		\
 		{ EXTENT_MAP_HOLE, 	"HOLE" 		},		\
 		{ EXTENT_MAP_INLINE, 	"INLINE" 	},		\
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 3e68366..533c49f 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -205,6 +205,19 @@
 		ftrace_print_symbols_seq(p, value, symbols);		\
 	})
 
+#undef __print_symbolic_u64
+#if BITS_PER_LONG == 32
+#define __print_symbolic_u64(value, symbol_array...)			\
+	({								\
+		static const struct trace_print_flags_u64 symbols[] =	\
+			{ symbol_array, { -1, NULL } };			\
+		ftrace_print_symbols_seq_u64(p, value, symbols);	\
+	})
+#else
+#define __print_symbolic_u64(value, symbol_array...)			\
+			__print_symbolic(value, symbol_array)
+#endif
+
 #undef __print_hex
 #define __print_hex(buf, buf_len) ftrace_print_hex_seq(p, buf, buf_len)
 
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 456be90..47aafa9 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -353,6 +353,33 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 }
 EXPORT_SYMBOL(ftrace_print_symbols_seq);
 
+#if BITS_PER_LONG == 32
+const char *
+ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
+			 const struct trace_print_flags_u64 *symbol_array)
+{
+	int i;
+	const char *ret = p->buffer + p->len;
+
+	for (i = 0;  symbol_array[i].name; i++) {
+
+		if (val != symbol_array[i].mask)
+			continue;
+
+		trace_seq_puts(p, symbol_array[i].name);
+		break;
+	}
+
+	if (!p->len)
+		trace_seq_printf(p, "0x%llx", val);
+
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
+#endif
+
 const char *
 ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
 {
-- 
1.6.5.2