tools lib fs debugfs: Introduce debugfs__strerror_open_tp

There will be other cases where not just a tracepoint event is being
opened below the debugfs mountpoint, but it is rather common, so provide
one helper for that.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-q6e6zct49ql6nbcw8kkg0lbj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index eaaa540..7e935f10 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -2071,9 +2071,9 @@
 		goto out_error_mem;
 
 	if (trace->sched &&
-		perf_evlist__add_newtp(evlist, "sched", "sched_stat_runtime",
-				trace__sched_stat_runtime))
-		goto out_error_tp;
+	    perf_evlist__add_newtp(evlist, "sched", "sched_stat_runtime",
+				   trace__sched_stat_runtime))
+		goto out_error_sched_stat_runtime;
 
 	err = perf_evlist__create_maps(evlist, &trace->opts.target);
 	if (err < 0) {
@@ -2203,9 +2203,12 @@
 {
 	char errbuf[BUFSIZ];
 
-out_error_tp:
+out_error_sched_stat_runtime:
+	debugfs__strerror_open_tp(errno, errbuf, sizeof(errbuf), "sched", "sched_stat_runtime");
+	goto out_error;
+
 out_error_raw_syscalls:
-	debugfs__strerror_open(errno, errbuf, sizeof(errbuf), "tracing/events/raw_syscalls");
+	debugfs__strerror_open_tp(errno, errbuf, sizeof(errbuf), "raw_syscalls", "sys_(enter|exit)");
 	goto out_error;
 
 out_error_mmap: