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: 583359646f ("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>
This commit is contained in:
Namhyung Kim 2017-06-18 23:23:00 +09:00 committed by Arnaldo Carvalho de Melo
parent e7bd9ba20a
commit 29681bc5bb

View File

@ -231,6 +231,8 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
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 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
goto out_close_fd;
}
setup_pager();
perf_evlist__start_workload(ftrace->evlist);
while (!done) {