lockdep: add lock_class information to lock_chain and output it
This patch records array of lock_class into lock_chain, and export
lock_chain information via /proc/lockdep_chains.
It is based on x86/master branch of git-x86 tree, and has been tested
on x86_64 platform.
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>
diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index 688c5f1..14d052c 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -178,6 +178,93 @@
.release = seq_release,
};
+static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct lock_chain *chain;
+
+ (*pos)++;
+
+ if (v == SEQ_START_TOKEN)
+ chain = m->private;
+ else {
+ chain = v;
+
+ if (*pos < nr_lock_chains)
+ chain = lock_chains + *pos;
+ else
+ chain = NULL;
+ }
+
+ return chain;
+}
+
+static void *lc_start(struct seq_file *m, loff_t *pos)
+{
+ if (*pos == 0)
+ return SEQ_START_TOKEN;
+
+ if (*pos < nr_lock_chains)
+ return lock_chains + *pos;
+
+ return NULL;
+}
+
+static void lc_stop(struct seq_file *m, void *v)
+{
+}
+
+static int lc_show(struct seq_file *m, void *v)
+{
+ struct lock_chain *chain = v;
+ struct lock_class *class;
+ int i;
+
+ if (v == SEQ_START_TOKEN) {
+ seq_printf(m, "all lock chains:\n");
+ return 0;
+ }
+
+ seq_printf(m, "irq_context: %d\n", chain->irq_context);
+
+ for (i = 0; i < chain->depth; i++) {
+ class = lock_chain_get_class(chain, i);
+ seq_printf(m, "[%p] ", class->key);
+ print_name(m, class);
+ seq_puts(m, "\n");
+ }
+ seq_puts(m, "\n");
+
+ return 0;
+}
+
+static const struct seq_operations lockdep_chains_ops = {
+ .start = lc_start,
+ .next = lc_next,
+ .stop = lc_stop,
+ .show = lc_show,
+};
+
+static int lockdep_chains_open(struct inode *inode, struct file *file)
+{
+ int res = seq_open(file, &lockdep_chains_ops);
+ if (!res) {
+ struct seq_file *m = file->private_data;
+
+ if (nr_lock_chains)
+ m->private = lock_chains;
+ else
+ m->private = NULL;
+ }
+ return res;
+}
+
+static const struct file_operations proc_lockdep_chains_operations = {
+ .open = lockdep_chains_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
static void lockdep_stats_debug_show(struct seq_file *m)
{
#ifdef CONFIG_DEBUG_LOCKDEP
@@ -294,6 +381,8 @@
#ifdef CONFIG_PROVE_LOCKING
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);
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
@@ -661,6 +750,8 @@
static int __init lockdep_proc_init(void)
{
proc_create("lockdep", S_IRUSR, NULL, &proc_lockdep_operations);
+ proc_create("lockdep_chains", S_IRUSR, NULL,
+ &proc_lockdep_chains_operations);
proc_create("lockdep_stats", S_IRUSR, NULL,
&proc_lockdep_stats_operations);