perf ftrace: Move setup_pager before opening trace_pipe
The 'perf ftrace' command fails to reset tracer after finishing
recording like below:
$ sudo perf ftrace -v hello
write 'nop' to tracing/current_tracer failed: Device or resource busy
...
This is because the trace_pipe file is open in pager process. Move the
pager setup to before opening the file.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Fixes: 583359646fde ("perf ftrace: Use pager for displaying result")
Link: http://lkml.kernel.org/r/20170618142302.25390-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 966a94f..982b98e 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -231,6 +231,8 @@
goto out_reset;
}
+ setup_pager();
+
trace_file = get_tracing_file("trace_pipe");
if (!trace_file) {
pr_err("failed to open trace_pipe\n");
@@ -254,8 +256,6 @@
goto out_close_fd;
}
- setup_pager();
-
perf_evlist__start_workload(ftrace->evlist);
while (!done) {