From 9c35dd7f8bda1849dcb430be99325504221048df Mon Sep 17 00:00:00 2001 From: Jarek Poplawski Date: Thu, 22 Mar 2007 00:11:28 -0800 Subject: [PATCH] lockdep: debug_show_all_locks & debug_show_held_locks vs. debug_locks lockdep's data shouldn't be used when debug_locks == 0 because it's not updated after this, so it's more misleading than helpful. PS: probably lockdep's current-> fields should be reset after it turns debug_locks off: so, after printing a bug report, but before return from exported functions, but there are really a lot of these possibilities (e.g. after DEBUG_LOCKS_WARN_ON), so, something could be missed. (Of course direct use of this fields isn't recommended either.) Reported-by: Folkert van Heusden Inspired-by: Oleg Nesterov Signed-off-by: Jarek Poplawski Acked-by: Peter Zijlstra Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/lockdep.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 8dc24c92dc6d..7065a687ac54 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2742,6 +2742,10 @@ void debug_show_all_locks(void) int count = 10; int unlock = 1; + if (unlikely(!debug_locks)) { + printk("INFO: lockdep is turned off.\n"); + return; + } printk("\nShowing all locks held in the system:\n"); /* @@ -2785,6 +2789,10 @@ EXPORT_SYMBOL_GPL(debug_show_all_locks); void debug_show_held_locks(struct task_struct *task) { + if (unlikely(!debug_locks)) { + printk("INFO: lockdep is turned off.\n"); + return; + } lockdep_print_held_locks(task); } -- cgit v1.2.3