[PATCH 3.10 130/139] tracing: Apply trace_clock changes to instance max buffer

[Willy Tarreau]

From: Baohong Liu <baohong.liu@xxxxxxxxx>

commit 170b3b1050e28d1ba0700e262f0899ffa4fccc52 upstream.

Currently trace_clock timestamps are applied to both regular and max
buffers only for global trace. For instance trace, trace_clock
timestamps are applied only to regular buffer. But, regular and max
buffers can be swapped, for example, following a snapshot. So, for
instance trace, bad timestamps can be seen following a snapshot.
Let's apply trace_clock timestamps to instance max buffer as well.

Link: http://lkml.kernel.org/r/ebdb168d0be042dcdf51f81e696b17fabe3609c1.1504642143.git.tom.zanussi@xxxxxxxxxxxxxxx

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 277ba0446 ("tracing: Add interface to allow multiple trace buffers")
Signed-off-by: Baohong Liu <baohong.liu@xxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
 kernel/trace/trace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index edffb67..df820d9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4654,7 +4654,7 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
 	tracing_reset_online_cpus(&tr->trace_buffer);
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-	if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer)
+	if (tr->max_buffer.buffer)
 		ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func);
 	tracing_reset_online_cpus(&tr->max_buffer);
 #endif
-- 
2.8.0.rc2.1.gbe9624a