Make /proc/slabinfo use seq_list_xxx helpers

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.

[adobriyan@sw.ru: Wrong pointer was used as kmem_cache pointer]
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 24 deletions

diff --git a/mm/slab.c b/mm/slab.c
index b344e670712..a6a2fcf8195 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -4157,26 +4157,17 @@ static void print_slabinfo_header(struct seq_file *m)
 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)
@@ -4186,7 +4177,7 @@ static void s_stop(struct seq_file *m, void *p)
 
 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;
@@ -4355,17 +4346,8 @@ ssize_t slabinfo_write(struct file *file, const char __user * buffer,
 
 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)
@@ -4430,7 +4412,7 @@ static void show_symbol(struct seq_file *m, unsigned long address)
 
 static int leaks_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;
         struct kmem_list3 *l3;
         const char *name;