[GIT PULL] tracing fix

[Ingo Molnar <mingo@elte.hu>]

Linus,

Please pull the latest tracing-fixes-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git tracing-fixes-for-linus

 Thanks,

	Ingo

------------------>
Steven Rostedt (1):
      ring-buffer: Do 8 byte alignment for 64 bit that can not handle 4 byte align


 kernel/trace/ring_buffer.c |   14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 05a9f83..d1187ef 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -207,6 +207,14 @@ EXPORT_SYMBOL_GPL(tracing_is_on);
 #define RB_MAX_SMALL_DATA	(RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
 #define RB_EVNT_MIN_SIZE	8U	/* two 32bit words */
 
+#if !defined(CONFIG_64BIT) || defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
+# define RB_FORCE_8BYTE_ALIGNMENT	0
+# define RB_ARCH_ALIGNMENT		RB_ALIGNMENT
+#else
+# define RB_FORCE_8BYTE_ALIGNMENT	1
+# define RB_ARCH_ALIGNMENT		8U
+#endif
+
 /* define RINGBUF_TYPE_DATA for 'case RINGBUF_TYPE_DATA:' */
 #define RINGBUF_TYPE_DATA 0 ... RINGBUF_TYPE_DATA_TYPE_LEN_MAX
 
@@ -1547,7 +1555,7 @@ rb_update_event(struct ring_buffer_event *event,
 
 	case 0:
 		length -= RB_EVNT_HDR_SIZE;
-		if (length > RB_MAX_SMALL_DATA)
+		if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT)
 			event->array[0] = length;
 		else
 			event->type_len = DIV_ROUND_UP(length, RB_ALIGNMENT);
@@ -1722,11 +1730,11 @@ static unsigned rb_calculate_event_length(unsigned length)
 	if (!length)
 		length = 1;
 
-	if (length > RB_MAX_SMALL_DATA)
+	if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT)
 		length += sizeof(event.array[0]);
 
 	length += RB_EVNT_HDR_SIZE;
-	length = ALIGN(length, RB_ALIGNMENT);
+	length = ALIGN(length, RB_ARCH_ALIGNMENT);
 
 	return length;
 }