perf tools: Simplify debugfs mountpoint handling code

We don't need to have two PATH_MAX char sized arrays holding it, just
one in util/debugfs.c will do.

Also rename debugfs_path to tracing_events_path, as it is not the path
to debugfs, that is debugfs_mountpoint. Both are now accessible.

This will allow accessing this code in the perf python binding without
having to drag in perf.c and util/parse-events.c.

The defaults for these variables are the canonical "/sys/kernel/debug"
and "/sys/kernel/debug/tracing/events/", removing the need for simple
tools to call debugfs_mount(NULL).

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-ug9jvtjrsqbluuhqqxpvg30f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/tools/perf/util/debugfs.h b/tools/perf/util/debugfs.h
index 8cd3fa0af88..4a878f735eb 100644
--- a/tools/perf/util/debugfs.h
+++ b/tools/perf/util/debugfs.h
@@ -6,9 +6,13 @@ int debugfs_valid_mountpoint(const char *debugfs);
 int debugfs_valid_entry(const char *path);
 char *debugfs_mount(const char *mountpoint);
 int debugfs_umount(void);
+void debugfs_set_path(const char *mountpoint);
 int debugfs_write(const char *entry, const char *value);
 int debugfs_read(const char *entry, char *buffer, size_t size);
 void debugfs_force_cleanup(void);
 int debugfs_make_path(const char *element, char *buffer, int size);
 
+extern char debugfs_mountpoint[];
+extern char tracing_events_path[];
+
 #endif /* __DEBUGFS_H__ */