tracing: Show raw time stamp on stats per cpu using counter or tsc mode for trace_clock

Show raw time stamp values for stats per cpu if you choose counter or tsc mode
for trace_clock. Although a unit of tracing time stamp is nsec in local or global mode,
the units in counter and TSC mode are tracing counter and cycles respectively.
Link: http://lkml.kernel.org/r/1352837903-32191-3-git-send-email-dhsharp@google.com

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: David Sharp <dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 17 insertions, 6 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d943e69569cd..b69cc380322d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4388,13 +4388,24 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
         cnt = ring_buffer_bytes_cpu(tr->buffer, cpu);
         trace_seq_printf(s, "bytes: %ld\n", cnt);
 
-        t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu));
-        usec_rem = do_div(t, USEC_PER_SEC);
-        trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", t, usec_rem);
+        if (trace_clocks[trace_clock_id].in_ns) {
+                /* local or global for trace_clock */
+                t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu));
+                usec_rem = do_div(t, USEC_PER_SEC);
+                trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n",
+                                                                t, usec_rem);
+
+                t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu));
+                usec_rem = do_div(t, USEC_PER_SEC);
+                trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem);
+        } else {
+                /* counter or tsc mode for trace_clock */
+                trace_seq_printf(s, "oldest event ts: %llu\n",
+                                ring_buffer_oldest_event_ts(tr->buffer, cpu));
 
-        t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu));
-        usec_rem = do_div(t, USEC_PER_SEC);
-        trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem);
+                trace_seq_printf(s, "now ts: %llu\n",
+                                ring_buffer_time_stamp(tr->buffer, cpu));
+        }
 
         cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu);
         trace_seq_printf(s, "dropped events: %ld\n", cnt);