seq_file: add seq_list_*_percpu helpers

When we convert the file_lock_list to a set of percpu lists, we'll need
a way to iterate over them in order to output /proc/locks info. Add
some seq_list_*_percpu helpers to handle that.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Jeff Layton 2013-06-21 08:58:21 -04:00 committed by Al Viro
parent 99b072bb38
commit 0bc77381c1
2 changed files with 60 additions and 0 deletions

View File

@ -921,3 +921,57 @@ struct hlist_node *seq_hlist_next_rcu(void *v,
return rcu_dereference(node->next);
}
EXPORT_SYMBOL(seq_hlist_next_rcu);
/**
* seq_hlist_start_precpu - start an iteration of a percpu hlist array
* @head: pointer to percpu array of struct hlist_heads
* @cpu: pointer to cpu "cursor"
* @pos: start position of sequence
*
* Called at seq_file->op->start().
*/
struct hlist_node *
seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos)
{
struct hlist_node *node;
for_each_possible_cpu(*cpu) {
hlist_for_each(node, per_cpu_ptr(head, *cpu)) {
if (pos-- == 0)
return node;
}
}
return NULL;
}
EXPORT_SYMBOL(seq_hlist_start_percpu);
/**
* seq_hlist_next_percpu - move to the next position of the percpu hlist array
* @v: pointer to current hlist_node
* @head: pointer to percpu array of struct hlist_heads
* @cpu: pointer to cpu "cursor"
* @pos: start position of sequence
*
* Called at seq_file->op->next().
*/
struct hlist_node *
seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head,
int *cpu, loff_t *pos)
{
struct hlist_node *node = v;
++*pos;
if (node->next)
return node->next;
for (*cpu = cpumask_next(*cpu, cpu_possible_mask); *cpu < nr_cpu_ids;
*cpu = cpumask_next(*cpu, cpu_possible_mask)) {
struct hlist_head *bucket = per_cpu_ptr(head, *cpu);
if (!hlist_empty(bucket))
return bucket->first;
}
return NULL;
}
EXPORT_SYMBOL(seq_hlist_next_percpu);

View File

@ -173,4 +173,10 @@ extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
extern struct hlist_node *seq_hlist_next_rcu(void *v,
struct hlist_head *head,
loff_t *ppos);
/* Helpers for iterating over per-cpu hlist_head-s in seq_files */
extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos);
extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos);
#endif