diff options
| -rw-r--r-- | kernel/lockdep.c | 16 | ||||
| -rw-r--r-- | kernel/lockdep_internals.h | 2 | ||||
| -rw-r--r-- | kernel/lockdep_proc.c | 6 |
3 files changed, 17 insertions, 7 deletions
diff --git a/kernel/lockdep.c b/kernel/lockdep.c index a796f1f38ac5..7553a28b99cd 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -1459,7 +1459,7 @@ out_bug: unsigned long nr_lock_chains; struct lock_chain lock_chains[MAX_LOCKDEP_CHAINS]; -atomic_t nr_chain_hlocks; +int nr_chain_hlocks; static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS]; struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i) @@ -1481,7 +1481,7 @@ static inline int lookup_chain_cache(struct task_struct *curr, struct list_head *hash_head = chainhashentry(chain_key); struct lock_chain *chain; struct held_lock *hlock_curr, *hlock_next; - int i, j, n; + int i, j, n, cn; if (DEBUG_LOCKS_WARN_ON(!irqs_disabled())) return 0; @@ -1540,9 +1540,15 @@ cache_hit: } i++; chain->depth = curr->lockdep_depth + 1 - i; - n = atomic_add_return(chain->depth, &nr_chain_hlocks); - if (unlikely(n < MAX_LOCKDEP_CHAIN_HLOCKS)) { - chain->base = n - chain->depth; + cn = nr_chain_hlocks; + while (cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS) { + n = cmpxchg(&nr_chain_hlocks, cn, cn + chain->depth); + if (n == cn) + break; + cn = n; + } + if (likely(cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) { + chain->base = cn; for (j = 0; j < chain->depth - 1; j++, i++) { int lock_id = curr->held_locks[i].class - lock_classes; chain_hlocks[chain->base + j] = lock_id; diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h index db09b176dd34..c3600a091a28 100644 --- a/kernel/lockdep_internals.h +++ b/kernel/lockdep_internals.h @@ -44,7 +44,7 @@ struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i); extern unsigned long nr_lock_classes; extern unsigned long nr_list_entries; extern unsigned long nr_lock_chains; -extern atomic_t nr_chain_hlocks; +extern int nr_chain_hlocks; extern unsigned long nr_stack_trace_entries; extern unsigned int nr_hardirq_chains; diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c index 14d052c8a835..9b0e940e2545 100644 --- a/kernel/lockdep_proc.c +++ b/kernel/lockdep_proc.c @@ -178,6 +178,7 @@ static const struct file_operations proc_lockdep_operations = { .release = seq_release, }; +#ifdef CONFIG_PROVE_LOCKING static void *lc_next(struct seq_file *m, void *v, loff_t *pos) { struct lock_chain *chain; @@ -264,6 +265,7 @@ static const struct file_operations proc_lockdep_chains_operations = { .llseek = seq_lseek, .release = seq_release, }; +#endif /* CONFIG_PROVE_LOCKING */ static void lockdep_stats_debug_show(struct seq_file *m) { @@ -382,7 +384,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v) seq_printf(m, " dependency chains: %11lu [max: %lu]\n", nr_lock_chains, MAX_LOCKDEP_CHAINS); seq_printf(m, " dependency chain hlocks: %11d [max: %lu]\n", - atomic_read(&nr_chain_hlocks), MAX_LOCKDEP_CHAIN_HLOCKS); + nr_chain_hlocks, MAX_LOCKDEP_CHAIN_HLOCKS); #endif #ifdef CONFIG_TRACE_IRQFLAGS @@ -750,8 +752,10 @@ static const struct file_operations proc_lock_stat_operations = { static int __init lockdep_proc_init(void) { proc_create("lockdep", S_IRUSR, NULL, &proc_lockdep_operations); +#ifdef CONFIG_PROVE_LOCKING proc_create("lockdep_chains", S_IRUSR, NULL, &proc_lockdep_chains_operations); +#endif proc_create("lockdep_stats", S_IRUSR, NULL, &proc_lockdep_stats_operations); |