[PATCH v5 12/25] trace-cmd library: Do not write CPUs with empty trace data

["Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>]

Trace file version 7 has more flexible design, which allows to write only
CPUs with trace data in the file. If a CPU has no recorded trace data,
do not put it in the trace file version 7.

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
 lib/trace-cmd/trace-output.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/trace-cmd/trace-output.c b/lib/trace-cmd/trace-output.c
index 028ad580..2ed7155b 100644
--- a/lib/trace-cmd/trace-output.c
+++ b/lib/trace-cmd/trace-output.c
@@ -2079,8 +2079,10 @@ int tracecmd_write_cpu_data(struct tracecmd_output *handle,
 
 	if (i < cpus)
 		ret = -1;
-	else
+	else if (size || !HAS_SECTIONS(handle))
 		ret = out_write_cpu_data(handle, cpus, data, buff_name);
+	else
+		ret = 0;
 
 	for (i--; i >= 0; i--)
 		close(data[i].fd);
-- 
2.33.1