mm: convert totalram_pages and totalhigh_pages variables to atomic

totalram_pages and totalhigh_pages are made static inline function.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Suggested-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/mm/util.c b/mm/util.c
index 8bf08b5b5760..4df23d64aac7 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -593,7 +593,7 @@ unsigned long vm_commit_limit(void)
         if (sysctl_overcommit_kbytes)
                 allowed = sysctl_overcommit_kbytes >> (PAGE_SHIFT - 10);
         else
-                allowed = ((totalram_pages - hugetlb_total_pages())
+                allowed = ((totalram_pages() - hugetlb_total_pages())
                            * sysctl_overcommit_ratio / 100);
         allowed += total_swap_pages;