From 0632eb3d7563d6a76d49a3860b6352d800c92854 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 22 Feb 2010 17:04:47 -0800 Subject: rcu: Integrate rcu_dereference_check() message into lockdep Make rcu_dereference_check() print the list of held locks in addition to the stack dump to ease debugging. Signed-off-by: Paul E. McKenney Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-3-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'kernel') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index c62ec14609b9..672c436946ce 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -3809,3 +3809,21 @@ void lockdep_sys_exit(void) lockdep_print_held_locks(curr); } } + +void lockdep_rcu_dereference(const char *file, const int line) +{ + struct task_struct *curr = current; + + if (!debug_locks_off()) + return; + printk("\n==============================================\n"); + printk( "[ BUG: Unsafe rcu_dereference_check() usage! ]\n"); + printk( "----------------------------------------------\n"); + printk("%s:%d invoked rcu_dereference_check() without protection!\n", + file, line); + printk("\nother info that might help us debug this:\n\n"); + lockdep_print_held_locks(curr); + printk("\nstack backtrace:\n"); + dump_stack(); +} +EXPORT_SYMBOL_GPL(lockdep_rcu_dereference); -- cgit v1.2.2