[Devel] [PATCH 14/15] Make /proc/slabinfo use seq_list_xxx helpers

[Pavel Emelianov]

This entry prints a header in .start callback. This is OK,
but the more elegant solution would be to move this into the
.show callback and use seq_list_start_head() in .start one.

I have left it as is in order to make the patch just switch
to new API and noting more.

Signed-off-by: Pavel Emelianov <xemul at openvz.org>

---

diff --git a/mm/slab.c b/mm/slab.c
index 6edfd34..faad0d7 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -4161,26 +4161,17 @@ static void print_slabinfo_header(struct
 static void *s_start(struct seq_file *m, loff_t *pos)
 {
 	loff_t n = *pos;
-	struct list_head *p;
 
 	mutex_lock(&cache_chain_mutex);
 	if (!n)
 		print_slabinfo_header(m);
-	p = cache_chain.next;
-	while (n--) {
-		p = p->next;
-		if (p == &cache_chain)
-			return NULL;
-	}
-	return list_entry(p, struct kmem_cache, next);
+
+	return seq_list_start(&cache_chain, *pos);
 }
 
 static void *s_next(struct seq_file *m, void *p, loff_t *pos)
 {
-	struct kmem_cache *cachep = p;
-	++*pos;
-	return cachep->next.next == &cache_chain ?
-		NULL : list_entry(cachep->next.next, struct kmem_cache, next);
+	return seq_list_next(p, &cache_chain, pos);
 }
 
 static void s_stop(struct seq_file *m, void *p)
@@ -4190,7 +4181,7 @@ static void s_stop(struct seq_file *m, v
 
 static int s_show(struct seq_file *m, void *p)
 {
-	struct kmem_cache *cachep = p;
+	struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next);
 	struct slab *slabp;
 	unsigned long active_objs;
 	unsigned long num_objs;
@@ -4359,17 +4350,8 @@ ssize_t slabinfo_write(struct file *file
 
 static void *leaks_start(struct seq_file *m, loff_t *pos)
 {
-	loff_t n = *pos;
-	struct list_head *p;
-
 	mutex_lock(&cache_chain_mutex);
-	p = cache_chain.next;
-	while (n--) {
-		p = p->next;
-		if (p == &cache_chain)
-			return NULL;
-	}
-	return list_entry(p, struct kmem_cache, next);
+	return seq_list_start(&cache_chain, *pos);
 }
 
 static inline int add_caller(unsigned long *n, unsigned long v)