Commit cd1a28e8 authored by Huang, Ying's avatar Huang, Ying Committed by Ingo Molnar
Browse files

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: default avatarHuang Ying <ying.huang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 443cd507

kernel/lockdep.c

+11 −5
Original line number Diff line number Diff line
@@ -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;

kernel/lockdep_internals.h

+1 −1
Original line number Diff line number Diff line
@@ -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;

kernel/lockdep_proc.c

+5 −1
Original line number Diff line number Diff line
@@ -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);

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