Indirect dependency redundancy check was added for cross-release, which has been reverted. Then suggested by Peter, only when setting CONFIG_LOCKDEP_SMALL it takes effect.
With (recursive) read-write lock types considered in dependency graph, indirect dependency redundancy check would be very complicated if not impossible to be correctly done. Lets remove it for good. Signed-off-by: Yuyang Du <[email protected]> --- kernel/locking/lockdep.c | 41 -------------------------------------- kernel/locking/lockdep_internals.h | 1 - kernel/locking/lockdep_proc.c | 2 -- 3 files changed, 44 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index f171c6e..c61fdef 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1744,38 +1744,6 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class) 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. - * - * Print an error and return 2 if it does or 1 if it does not. - */ -static noinline int -check_redundant(struct held_lock *src, struct held_lock *target) -{ - int ret; - struct lock_list *uninitialized_var(target_entry); - struct lock_list src_entry = { - .class = hlock_class(src), - .parent = NULL, - }; - - debug_atomic_inc(nr_redundant_checks); - - ret = check_path(hlock_class(target), &src_entry, &target_entry); - - if (!ret) { - debug_atomic_inc(nr_redundant); - ret = 2; - } else if (ret < 0) - ret = 0; - - return ret; -} -#endif - #ifdef CONFIG_TRACE_IRQFLAGS static inline int usage_accumulate(struct lock_list *entry, void *mask) @@ -2437,15 +2405,6 @@ static inline void inc_chains(void) } } -#ifdef CONFIG_LOCKDEP_SMALL - /* - * Is the <prev> -> <next> link redundant? - */ - ret = check_redundant(prev, next); - if (ret != 1) - return ret; -#endif - if (!trace->nr_entries && !save_trace(trace)) return 0; diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index cc83568..e9a8ed6 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -170,7 +170,6 @@ struct lockdep_stats { unsigned long redundant_softirqs_on; unsigned long redundant_softirqs_off; int nr_unused_locks; - unsigned int nr_redundant_checks; unsigned int nr_redundant; unsigned int nr_cyclic_checks; unsigned int nr_find_usage_forwards_checks; diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index 9c49ec6..58ed889 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -178,8 +178,6 @@ static void lockdep_stats_debug_show(struct seq_file *m) debug_atomic_read(chain_lookup_hits)); seq_printf(m, " cyclic checks: %11llu\n", debug_atomic_read(nr_cyclic_checks)); - seq_printf(m, " redundant checks: %11llu\n", - debug_atomic_read(nr_redundant_checks)); seq_printf(m, " redundant links: %11llu\n", debug_atomic_read(nr_redundant)); seq_printf(m, " find-mask forwards checks: %11llu\n", -- 1.8.3.1
