lockstat: warn about disabled lock debugging

Avoid confusion and clearly state lock debugging got disabled.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index b51064ce564a..d7135aa2d2c4 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -601,6 +601,10 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
 static void seq_header(struct seq_file *m)
 {
         seq_printf(m, "lock_stat version 0.3\n");
+
+        if (unlikely(!debug_locks))
+                seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n");
+
         seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
         seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s "
                         "%14s %14s\n",