[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/mm/hugetlb.c b/mm/hugetlb.c
index 61d3806..094455b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -286,7 +286,7 @@
entry = *src_pte;
ptepage = pte_page(entry);
get_page(ptepage);
- add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
+ add_mm_counter(dst, file_rss, HPAGE_SIZE / PAGE_SIZE);
set_huge_pte_at(dst, addr, dst_pte, entry);
}
spin_unlock(&src->page_table_lock);
@@ -324,7 +324,7 @@
page = pte_page(pte);
put_page(page);
- add_mm_counter(mm, rss, - (HPAGE_SIZE / PAGE_SIZE));
+ add_mm_counter(mm, file_rss, (int) -(HPAGE_SIZE / PAGE_SIZE));
}
flush_tlb_range(vma, start, end);
}
@@ -386,7 +386,7 @@
goto out;
}
}
- add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
+ add_mm_counter(mm, file_rss, HPAGE_SIZE / PAGE_SIZE);
set_huge_pte_at(mm, addr, pte, make_huge_pte(vma, page));
}
out: