[PATCH 4.14 081/109] mm: treat indirectly reclaimable memory as available in MemAvailable

Greg Kroah-Hartman
2018-10-16T17:22:21Z

From: Roman Gushchin <guro@fb.com>

commit 034ebf65c3c21d85b963d39f992258a64a85e3a9 upstream.

Adjust /proc/meminfo MemAvailable calculation by adding the amount of
indirectly reclaimable memory (rounded to the PAGE_SIZE).

Link: http://lkml.kernel.org/r/20180305133743.12746-4-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
mm/page_alloc.c | 7 +++++++
1 file changed, 7 insertions(+)

--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4557,6 +4557,13 @@ long si_mem_available(void)
min(global_node_page_state(NR_SLAB_RECLAIMABLE) / 2,
wmark_low);

+ /*
+ * Part of the kernel memory, which can be released under memory
+ * pressure.
+ */
+ available += global_node_page_state(NR_INDIRECTLY_RECLAIMABLE_BYTES) >>
+ PAGE_SHIFT;
+
if (available < 0)
available = 0;
return available;