lockdep: add lock_class information to lock_chain and output it

It is based on x86/master branch of git-x86 tree, and has been tested
on x86_64 platform.

ChangeLog:

v2:

- Enclosing proc file system related code into CONFIG_PROVE_LOCKING.

- Fix nr_chain_hlocks update code.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Huang, Ying 2008-06-23 11:20:54 +08:00 committed by Ingo Molnar
parent 443cd507ce
commit cd1a28e845
3 changed files with 17 additions and 7 deletions

View File

@ -1459,7 +1459,7 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
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 @@ static inline int lookup_chain_cache(struct task_struct *curr,
}
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;

View File

@ -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;

View File

@ -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);