mm/vmalloc.c: simplify /proc/vmallocinfo implementation
Many seq_file helpers exist for simplifying implementation of virtual
files especially, for /proc nodes. however, the helpers for iteration
over list_head are available but aren't adopted to implement
/proc/vmallocinfo currently.
Simplify /proc/vmallocinfo implementation by using existing seq_file
helpers.
Link: http://lkml.kernel.org/r/57FDF2E5.1000201@zoho.com
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index f2481cb..e73948a 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2574,32 +2574,13 @@
static void *s_start(struct seq_file *m, loff_t *pos)
__acquires(&vmap_area_lock)
{
- loff_t n = *pos;
- struct vmap_area *va;
-
spin_lock(&vmap_area_lock);
- va = list_first_entry(&vmap_area_list, typeof(*va), list);
- while (n > 0 && &va->list != &vmap_area_list) {
- n--;
- va = list_next_entry(va, list);
- }
- if (!n && &va->list != &vmap_area_list)
- return va;
-
- return NULL;
-
+ return seq_list_start(&vmap_area_list, *pos);
}
static void *s_next(struct seq_file *m, void *p, loff_t *pos)
{
- struct vmap_area *va = p, *next;
-
- ++*pos;
- next = list_next_entry(va, list);
- if (&next->list != &vmap_area_list)
- return next;
-
- return NULL;
+ return seq_list_next(p, &vmap_area_list, pos);
}
static void s_stop(struct seq_file *m, void *p)
@@ -2634,9 +2615,11 @@
static int s_show(struct seq_file *m, void *p)
{
- struct vmap_area *va = p;
+ struct vmap_area *va;
struct vm_struct *v;
+ va = list_entry(p, struct vmap_area, list);
+
/*
* s_show can encounter race with remove_vm_area, !VM_VM_AREA on
* behalf of vmap area is being tear down or vm_map_ram allocation.