diff options
| -rw-r--r-- | kernel/locking/lockdep.c | 91 |
1 files changed, 49 insertions, 42 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index f50f026772d7..f2ae8a65f667 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2130,46 +2130,6 @@ check_noncircular(struct held_lock *src, struct held_lock *target, return ret; } -#ifdef CONFIG_LOCKDEP_SMALL -/* - * Check that the dependency graph starting at <src> can lead to - * <target> or not. If it can, <src> -> <target> dependency is already - * in the graph. - * - * Return BFS_RMATCH if it does, or BFS_RMATCH if it does not, return BFS_E* if - * any error appears in the bfs search. - */ -static noinline enum bfs_result -check_redundant(struct held_lock *src, struct held_lock *target) -{ - enum bfs_result ret; - struct lock_list *target_entry; - struct lock_list src_entry; - - bfs_init_root(&src_entry, src); - /* - * Special setup for check_redundant(). - * - * To report redundant, we need to find a strong dependency path that - * is equal to or stronger than <src> -> <target>. So if <src> is E, - * we need to let __bfs() only search for a path starting at a -(E*)->, - * we achieve this by setting the initial node's ->only_xr to true in - * that case. And if <prev> is S, we set initial ->only_xr to false - * because both -(S*)-> (equal) and -(E*)-> (stronger) are redundant. - */ - src_entry.only_xr = src->read == 0; - - debug_atomic_inc(nr_redundant_checks); - - ret = check_path(target, &src_entry, hlock_equal, NULL, &target_entry); - - if (ret == BFS_RMATCH) - debug_atomic_inc(nr_redundant); - - return ret; -} -#endif - #ifdef CONFIG_TRACE_IRQFLAGS /* @@ -2706,6 +2666,55 @@ static inline int check_irq_usage(struct task_struct *curr, } #endif /* CONFIG_TRACE_IRQFLAGS */ +#ifdef CONFIG_LOCKDEP_SMALL +/* + * Check that the dependency graph starting at <src> can lead to + * <target> or not. If it can, <src> -> <target> dependency is already + * in the graph. + * + * Return BFS_RMATCH if it does, or BFS_RMATCH if it does not, return BFS_E* if + * any error appears in the bfs search. + */ +static noinline enum bfs_result +check_redundant(struct held_lock *src, struct held_lock *target) +{ + enum bfs_result ret; + struct lock_list *target_entry; + struct lock_list src_entry; + + bfs_init_root(&src_entry, src); + /* + * Special setup for check_redundant(). + * + * To report redundant, we need to find a strong dependency path that + * is equal to or stronger than <src> -> <target>. So if <src> is E, + * we need to let __bfs() only search for a path starting at a -(E*)->, + * we achieve this by setting the initial node's ->only_xr to true in + * that case. And if <prev> is S, we set initial ->only_xr to false + * because both -(S*)-> (equal) and -(E*)-> (stronger) are redundant. + */ + src_entry.only_xr = src->read == 0; + + debug_atomic_inc(nr_redundant_checks); + + ret = check_path(target, &src_entry, hlock_equal, NULL, &target_entry); + + if (ret == BFS_RMATCH) + debug_atomic_inc(nr_redundant); + + return ret; +} + +#else + +static inline enum bfs_result +check_redundant(struct held_lock *src, struct held_lock *target) +{ + return BFS_RNOMATCH; +} + +#endif + static void inc_chains(int irq_context) { if (irq_context & LOCK_CHAIN_HARDIRQ_CONTEXT) @@ -2926,7 +2935,6 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, } } -#ifdef CONFIG_LOCKDEP_SMALL /* * Is the <prev> -> <next> link redundant? */ @@ -2935,7 +2943,6 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, return 0; else if (ret == BFS_RMATCH) return 2; -#endif if (!*trace) { *trace = save_trace(); |