/*
* kernel/lockdep_proc.c
*
* Runtime locking correctness validator
*
* Started by Ingo Molnar:
*
* Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*
* Code for /proc/lockdep and /proc/lockdep_stats:
*
*/
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <linux/debug_locks.h>
#include "lockdep_internals.h"
static void *l_next(struct seq_file *m, void *v, loff_t *pos)
{
struct lock_class *class = v;
(*pos)++;
if (class->lock_entry.next != &all_lock_classes)
class = list_entry(class->lock_entry.next, struct lock_class,
lock_entry);
else
class = NULL;
m->private = class;
return class;
}
static void *l_start(struct seq_file *m, loff_t *pos)
{
struct lock_class *class = m->private;
if (&class->lock_entry == all_lock_classes.next)
seq_printf(m, "all lock classes:\n");
return class;
}
static void l_stop(struct seq_file *m, void *v)
{
}
static unsigned long count_forward_deps(struct lock_class *class)
{
struct lock_list *entry;
unsigned long ret = 1;
/*
* Recurse this class's dependency list:
*/
list_for_each_entry(entry, &class->locks_after, entry)
ret += count_forward_deps(entry->class);
return ret;
}
static unsigned long count_backward_deps(struct lock_class *class)
{
struct lock_list *entry;
unsigned long ret = 1;
/*
* Recurse this class's dependency list:
*/
list_for_each_entry(entry, &class->locks_before, entry)
ret += count_backward_deps(entry->class);
return ret;
}
static void print_name(struct seq_file *m, struct lock_class *class)
{
char str[128];
const char *name = class->name;
if (!name) {
name = __get_key_name(class->key, str);
seq_printf(m, "%s", name);
} else{
seq_printf(m, "%s", name);
if (class->name_version > 1)
seq_printf(m, "#%d", class->name_version);
if (class->subclass)
seq_printf(m, "/%d", class->subclass);
}
}
static int l_show(struct seq_file *m, void *v)
{
unsigned long nr_forward_deps, nr_backward_deps;
struct lock_class *class = m->private;
struct lock_list *entry;
char c1, c2, c3, c4;
seq_printf(m, "%p", class->key);
#ifdef CONFIG_DEBUG_LOCKDEP
seq_printf(m, " OPS:%8ld", class->ops);
#endif
nr_forward_deps = count_forward_deps(class);
seq_printf(m, " FD:%5ld", nr_forward_deps);
nr_backward_deps = count_backward_deps(class);
seq_printf(m, " BD:%5ld", nr_backward_deps);
get_usage_chars(class, &c1, &c2, &c3, &c4);
seq_printf(m, " %c%c%c%c", c1, c2, c3, c4);
seq_printf(m, ": ");
print_name(m, class);
seq_puts(m, "\n");
list_for_each_entry(entry, &class->locks_after, entry) {
if (entry->distance == 1) {
seq_printf(m, " -> [%p] ", entry->class);
print_name(m, entry->class);
seq_puts(m, "\n");
}
}
seq_puts(m, "\n");
return 0;
}
static const struct seq_operations lockdep_ops = {
.start = l_start,
.next = l_next,
.stop = l_stop,
.show = l_show,
};
static int lockdep_open(struct inode *inode, struct file *file)
{
int res = seq_open(file, &lockdep_ops);
if (!res) {
struct seq_file *m = file->private_data;
if (!list_empty(&all_lock_classes))
m->private = list_entry(all_lock_classes.next,
struct lock_class, lock_entry);
else
m->private = NULL;
}
return res;
}
static const struct file_operations proc_lockdep_operations = {
.open = lockdep_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static void lockdep_stats_debug_show(struct seq_file *m)
{
#ifdef CONFIG_DEBUG_LOCKDEP
unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
hi2 = debug_atomic_read(&hardirqs_off_events),
hr1 = debug_atomic_read(&redundant_hardirqs_on),
hr2 = debug_atomic_read(&redundant_hardirqs_off),
si1 = debug_atomic_read(&softirqs_on_events),
si2 = debug_atomic_read(&softirqs_off_events),
sr1 = debug_atomic_read(&redundant_softirqs_on),
sr2 = debug_atomic_read(&redundant_softirqs_off);
seq_printf(m, " chain lookup misses: %11u\n",
debug_atomic_read(&chain_lookup_misses));
seq_printf(m, " chain lookup hits: %11u\n",
debug_atomic_read(&chain_lookup_hits));
seq_printf(m, " cyclic checks: %11u\n",
debug_atomic_read(&nr_cyclic_checks));
seq_printf(m, " cyclic-check recursions: %11u\n",
debug_atomic_read(&nr_cyclic_check_recursions));
seq_printf(m, " find-mask forwards checks: %11u\n",
debug_atomic_read(&nr_find_usage_forwards_checks));
seq_printf(m, " find-mask forwards recursions: %11u\n",
debug_atomic_read(&nr_find_usage_forwards_recursions));
seq_printf(m, " find-mask backwards checks: %11u\n",
debug_atomic_read(&nr_find_usage_backwards_checks));
seq_printf(m, " find-mask backwards recursions:%11u\n",
debug_atomic_read(&nr_find_usage_backwards_recursions));
seq_printf(m, " hardirq on events: %11u\n", hi1);
seq_printf(m, " hardirq off events: %11u\n", hi2);
seq_printf(m, " redundant hardirq ons: %11u\n", hr1);
seq_printf(m, " redundant hardirq offs: %11u\n", hr2);
seq_printf(m, " softirq on events: %11u\n", si1);
seq_printf(m, " softirq off events: %11u\n", si2);
seq_printf(m, " redundant softirq ons: %11u\n", sr1);
seq_printf(m, " redundant softirq offs: %11u\n", sr2);
#endif
}
static int lockdep_stats_show(struct seq_file *m, void *v)
{
struct lock_class *class;
unsigned long nr_unused = 0, nr_uncategorized = 0,
nr_irq_safe = 0, nr_irq_unsafe = 0,
nr_softirq_safe = 0, nr_softirq_unsafe = 0,
nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
sum_forward_deps = 0, factor = 0;
list_for_each_entry(class, &all_lock_classes, lock_entry) {
if (class->usage_mask == 0)
nr_unused++;
if (class->usage_mask == LOCKF_USED)
nr_uncategorized++;
if (class->usage_mask & LOCKF_USED_IN_IRQ)
nr_irq_safe++;
if (class->usage_mask & LOCKF_ENABLED_IRQS)
nr_irq_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
nr_softirq_safe++;
if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS)
nr_softirq_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
nr_hardirq_safe++;
if (class->usage_mask & LOCKF_ENABLED_HARDIRQS)
nr_hardirq_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
nr_irq_read_safe++;
if (class->usage_mask & LOCKF_ENABLED_IRQS_READ)
nr_irq_read_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
nr_softirq_read_safe++;
if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS_READ)
nr_softirq_read_unsafe++;
if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
nr_hardirq_read_safe++;
if (class->usage_mask & LOCKF_ENABLED_HARDIRQS_READ)
nr_hardirq_read_unsafe++;
sum_forward_deps += count_forward_deps(class);
}
#ifdef CONFIG_DEBUG_LOCKDEP
DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
#endif
seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
nr_lock_classes, MAX_LOCKDEP_KEYS);
seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
nr_list_entries, MAX_LOCKDEP_ENTRIES);
seq_printf(m, " indirect dependencies: %11lu\n",
sum_forward_deps);
/*
* Total number of dependencies:
*
* All irq-safe locks may nest inside irq-unsafe locks,
* plus all the other known dependencies:
*/
seq_printf(m, " all direct dependencies: %11lu\n",
nr_irq_unsafe * nr_irq_safe +
nr_hardirq_unsafe * nr_hardirq_safe +
nr_list_entries);
/*
* Estimated factor between direct and indirect
* dependencies:
*/
if (nr_list_entries)
factor = sum_forward_deps / nr_list_entries;
seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
nr_lock_chains, MAX_LOCKDEP_CHAINS);
#ifdef CONFIG_TRACE_IRQFLAGS
seq_printf(m, " in-hardirq chains: %11u\n",
nr_hardirq_chains);
seq_printf(m, " in-softirq chains: %11u\n",
nr_softirq_chains);
#endif
seq_printf(m, " in-process chains: %11u\n",
nr_process_chains);
seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
seq_printf(m, " combined max dependencies: %11u\n",
(nr_hardirq_chains + 1) *
(nr_softirq_chains + 1) *
(nr_process_chains + 1)
);
seq_printf(m, " hardirq-safe locks: %11lu\n",
nr_hardirq_safe);
seq_printf(m, " hardirq-unsafe locks: %11lu\n",
nr_hardirq_unsafe);
seq_printf(m, " softirq-safe locks: %11lu\n",
nr_softirq_safe);
seq_printf(m, " softirq-unsafe locks: %11lu\n",
nr_softirq_unsafe);
seq_printf(m, " irq-safe locks: %11lu\n",
nr_irq_safe);
seq_printf(m, " irq-unsafe locks: %11lu\n",
nr_irq_unsafe);
seq_printf(m, " hardirq-read-safe locks: %11lu\n",
nr_hardirq_read_safe);
seq_printf(m, " hardirq-read-unsafe locks: %11lu\n",
nr_hardirq_read_unsafe);
seq_printf(m, " softirq-read-safe locks: %11lu\n",
nr_softirq_read_safe);
seq_printf(m, " softirq-read-unsafe locks: %11lu\n",
nr_softirq_read_unsafe);
seq_printf(m, " irq-read-safe locks: %11lu\n",
nr_irq_read_safe);
seq_printf(m, " irq-read-unsafe locks: %11lu\n",
nr_irq_read_unsafe);
seq_printf(m, " uncategorized locks: %11lu\n",
nr_uncategorized);
seq_printf(m, " unused locks: %11lu\n",
nr_unused);
seq_printf(m, " max locking depth: %11u\n",
max_lockdep_depth);
seq_printf(m, " max recursion depth: %11u\n",
max_recursion_depth);
lockdep_stats_debug_show(m);
seq_printf(m, " debug_locks: %11u\n",
debug_locks);
return 0;
}
static int lockdep_stats_open(struct inode *inode, struct file *file)
{
return single_open(file, lockdep_stats_show, NULL);
}
static const struct file_operations proc_lockdep_stats_operations = {
.open = lockdep_stats_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int __init lockdep_proc_init(void)
{
struct proc_dir_entry *entry;
entry = create_proc_entry("lockdep", S_IRUSR, NULL);
if (entry)
entry->proc_fops = &proc_lockdep_operations;
entry = create_proc_entry("lockdep_stats", S_IRUSR, NULL);
if (entry)
entry->proc_fops = &proc_lockdep_stats_operations;
return 0;
}
__initcall(lockdep_proc_init);
