[PATCH] mm: rss = file_rss + anon_rss
I was lazy when we added anon_rss, and chose to change as few places as
possible. So currently each anonymous page has to be counted twice, in rss
and in anon_rss. Which won't be so good if those are atomic counts in some
configurations.
Change that around: keep file_rss and anon_rss separately, and add them
together (with get_mm_rss macro) when the total is needed - reading two
atomics is much cheaper than updating two atomics. And update anon_rss
upfront, typically in memory.c, not tucked away in page_add_anon_rmap.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/fork.c b/kernel/fork.c
index 25caa02..2048ed7 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -321,7 +321,7 @@
INIT_LIST_HEAD(&mm->mmlist);
mm->core_waiters = 0;
mm->nr_ptes = 0;
- set_mm_counter(mm, rss, 0);
+ set_mm_counter(mm, file_rss, 0);
set_mm_counter(mm, anon_rss, 0);
spin_lock_init(&mm->page_table_lock);
rwlock_init(&mm->ioctx_list_lock);
@@ -499,7 +499,7 @@
if (retval)
goto free_pt;
- mm->hiwater_rss = get_mm_counter(mm,rss);
+ mm->hiwater_rss = get_mm_rss(mm);
mm->hiwater_vm = mm->total_vm;
good_mm:
