tracing: Apply trace_clock changes to instance max buffer

BugLink: http://bugs.launchpad.net/bugs/1720154
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@linux.intel.com
Fixes: 277ba0446 ("tracing: Add interface to allow multiple trace buffers")
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4373d71bb4fd0b851c2a838aef31f63a2f779044..5efb4b63174e26b35dd8d6043e34f1bae1426a81 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6226,7 +6226,7 @@ static int tracing_set_clock(struct trace_array *tr, const char *clockstr)
        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