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authorJeff Layton <jlayton@redhat.com>2013-06-21 08:58:21 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2013-07-08 13:36:41 +0400
commit0bc77381c1b1600e659eb7322c39d1753615722d (patch)
tree6e2adc4932f0fc136d08da5ba5adb032970a1b05 /fs
parent99b072bb38c9b398bc7c3fc8a0f30d0801f78750 (diff)
downloadlwn-0bc77381c1b1600e659eb7322c39d1753615722d.tar.gz
lwn-0bc77381c1b1600e659eb7322c39d1753615722d.zip
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>
Diffstat (limited to 'fs')
-rw-r--r--fs/seq_file.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 774c1eb7f1c9..3135c2525c76 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -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);