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>

2 files changed, 10 insertions, 0 deletions

diff --git a/tools/lib/api/fs/debugfs.c b/tools/lib/api/fs/debugfs.c
index 5e8f3913de43..bf9e21648894 100644
--- a/tools/lib/api/fs/debugfs.c
+++ b/tools/lib/api/fs/debugfs.c
@@ -125,3 +125,12 @@ int debugfs__strerror_open(int err, char *buf, size_t size, const char *filename
 
         return 0;
 }
+
+int debugfs__strerror_open_tp(int err, char *buf, size_t size, const char *sys, const char *name)
+{
+        char path[PATH_MAX];
+
+        snprintf(path, PATH_MAX, "tracing/events/%s/%s", sys, name ?: "*");
+
+        return debugfs__strerror_open(err, buf, size, path);
+}
diff --git a/tools/lib/api/fs/debugfs.h b/tools/lib/api/fs/debugfs.h
index a1799aecd4d5..0739881a9897 100644
--- a/tools/lib/api/fs/debugfs.h
+++ b/tools/lib/api/fs/debugfs.h
@@ -27,5 +27,6 @@ char *debugfs_mount(const char *mountpoint);
 extern char debugfs_mountpoint[];
 
 int debugfs__strerror_open(int err, char *buf, size_t size, const char *filename);
+int debugfs__strerror_open_tp(int err, char *buf, size_t size, const char *sys, const char *name);
 
 #endif /* __API_DEBUGFS_H__ */