perf tools: Introduce timestamp__scnprintf_usec()

Joonwoo reported that there's a mismatch between timestamps in script
and sched commands.  This was because of difference in printing the
timestamp.  Factor out the code and share it so that they can be in
sync.  Also I found that sched map has similar problem, fix it too.

Committer notes:

Fixed the max_lat_at bug introduced by Namhyung's original patch, as
pointed out by Joonwoo, and made it a function following the scnprintf()
model, i.e. returning the number of bytes formatted, and receiving as
the first parameter the object from where the data to the formatting is
obtained, renaming it from:

   char *timestamp_in_usec(char *bf, size_t size, u64 timestamp)

to

   int timestamp__scnprintf_usec(u64 timestamp, char *bf, size_t size)

Reported-by: Joonwoo Park <joonwoop@codeaurora.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20161024020246.14928-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 412fb6e65ac0..e1daff36d070 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -441,7 +441,6 @@ static void print_sample_start(struct perf_sample *sample,
 {
         struct perf_event_attr *attr = &evsel->attr;
         unsigned long secs;
-        unsigned long usecs;
         unsigned long long nsecs;
 
         if (PRINT_FIELD(COMM)) {
@@ -471,11 +470,14 @@ static void print_sample_start(struct perf_sample *sample,
                 nsecs = sample->time;
                 secs = nsecs / NSEC_PER_SEC;
                 nsecs -= secs * NSEC_PER_SEC;
-                usecs = nsecs / NSEC_PER_USEC;
+
                 if (nanosecs)
                         printf("%5lu.%09llu: ", secs, nsecs);
-                else
-                        printf("%5lu.%06lu: ", secs, usecs);
+                else {
+                        char sample_time[32];
+                        timestamp__scnprintf_usec(sample->time, sample_time, sizeof(sample_time));
+                        printf("%12s: ", sample_time);
+                }
         }
 }