mm/memcg: Use the node id in mem_cgroup_update_tree()

By using the node id in mem_cgroup_update_tree(), we can delete
soft_limit_tree_from_page() and mem_cgroup_page_nodeinfo().  Saves 42
bytes of kernel text on my config.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ee892daecb8bc263f62f1dc07b0352f75b2cb9fd..d57ff5c5d330a87aa0cc06c0b195e3fd1d876360 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -451,28 +451,12 @@ ino_t page_cgroup_ino(struct page *page)
        return ino;
 }
 
-static struct mem_cgroup_per_node *
-mem_cgroup_page_nodeinfo(struct mem_cgroup *memcg, struct page *page)
-{
-       int nid = page_to_nid(page);
-
-       return memcg->nodeinfo[nid];
-}
-
 static struct mem_cgroup_tree_per_node *
 soft_limit_tree_node(int nid)
 {
        return soft_limit_tree.rb_tree_per_node[nid];
 }
 
-static struct mem_cgroup_tree_per_node *
-soft_limit_tree_from_page(struct page *page)
-{
-       int nid = page_to_nid(page);
-
-       return soft_limit_tree.rb_tree_per_node[nid];
-}
-
 static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz,
                                         struct mem_cgroup_tree_per_node *mctz,
                                         unsigned long new_usage_in_excess)
@@ -543,13 +527,13 @@ static unsigned long soft_limit_excess(struct mem_cgroup *memcg)
        return excess;
 }
 
-static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page)
+static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid)
 {
        unsigned long excess;
        struct mem_cgroup_per_node *mz;
        struct mem_cgroup_tree_per_node *mctz;
 
-       mctz = soft_limit_tree_from_page(page);
+       mctz = soft_limit_tree_node(nid);
        if (!mctz)
                return;
        /*
@@ -557,7 +541,7 @@ static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page)
         * because their event counter is not touched.
         */
        for (; memcg; memcg = parent_mem_cgroup(memcg)) {
-               mz = mem_cgroup_page_nodeinfo(memcg, page);
+               mz = memcg->nodeinfo[nid];
                excess = soft_limit_excess(memcg);
                /*
                 * We have to update the tree if mz is on RB-tree or
@@ -884,7 +868,7 @@ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page)
                                                MEM_CGROUP_TARGET_SOFTLIMIT);
                mem_cgroup_threshold(memcg);
                if (unlikely(do_softlimit))
-                       mem_cgroup_update_tree(memcg, page);
+                       mem_cgroup_update_tree(memcg, page_to_nid(page));
        }
 }