diff mbox series

[v14,035/138] mm/memcg: Use the node id in mem_cgroup_update_tree()

Message ID 20210715033704.692967-36-willy@infradead.org (mailing list archive)
State New
Headers show
Series Memory folios | expand

Commit Message

Matthew Wilcox July 15, 2021, 3:35 a.m. UTC
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>
---
 mm/memcontrol.c | 24 ++++--------------------
 1 file changed, 4 insertions(+), 20 deletions(-)

Comments

David Howells Aug. 10, 2021, 8:06 p.m. UTC | #1
Matthew Wilcox (Oracle) <willy@infradead.org> wrote:

> 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>

Though I wonder if:

> -		mz = mem_cgroup_page_nodeinfo(memcg, page);
> +		mz = memcg->nodeinfo[nid];

should still have some sort of wrapper function.
Vlastimil Babka Aug. 11, 2021, 10:20 a.m. UTC | #2
On 7/15/21 5:35 AM, Matthew Wilcox (Oracle) wrote:
> 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>


Acked-by: Vlastimil Babka <vbabka@suse.cz>
Matthew Wilcox Aug. 13, 2021, 6:56 p.m. UTC | #3
On Tue, Aug 10, 2021 at 09:06:52PM +0100, David Howells wrote:
> Matthew Wilcox (Oracle) <willy@infradead.org> wrote:
> 
> > 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>
> 
> Though I wonder if:
> 
> > -		mz = mem_cgroup_page_nodeinfo(memcg, page);
> > +		mz = memcg->nodeinfo[nid];
> 
> should still have some sort of wrapper function.

I was asked to remove the wrapper function as it didn't provide enough
utility to warrant the indirection.
diff mbox series

Patch

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ee892daecb8b..d57ff5c5d330 100644
--- 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));
 	}
 }