mm: rename and change semantics of nr_indirectly_reclaimable_bytes
The vmstat counter NR_INDIRECTLY_RECLAIMABLE_BYTES was introduced by
commit eb59254608bc ("mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES") with
the goal of accounting objects that can be reclaimed, but cannot be
allocated via a SLAB_RECLAIM_ACCOUNT cache. This is now possible via
kmalloc() with __GFP_RECLAIMABLE flag, and the dcache external names user
is converted.
The counter is however still useful for accounting direct page allocations
(i.e. not slab) with a shrinker, such as the ION page pool. So keep it,
and:
- change granularity to pages to be more like other counters; sub-page
allocations should be able to use kmalloc
- rename the counter to NR_KERNEL_MISC_RECLAIMABLE
- expose the counter again in vmstat as "nr_kernel_misc_reclaimable"; we can
again remove the check for not printing "hidden" counters
Link: http://lkml.kernel.org/r/20180731090649.16028-5-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 747031c..20f25d0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4701,6 +4701,7 @@ long si_mem_available(void)
unsigned long pagecache;
unsigned long wmark_low = 0;
unsigned long pages[NR_LRU_LISTS];
+ unsigned long reclaimable;
struct zone *zone;
int lru;
@@ -4726,19 +4727,13 @@ long si_mem_available(void)
available += pagecache;
/*
- * Part of the reclaimable slab consists of items that are in use,
- * and cannot be freed. Cap this estimate at the low watermark.
+ * Part of the reclaimable slab and other kernel memory consists of
+ * items that are in use, and cannot be freed. Cap this estimate at the
+ * low watermark.
*/
- available += global_node_page_state(NR_SLAB_RECLAIMABLE) -
- 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;
+ reclaimable = global_node_page_state(NR_SLAB_RECLAIMABLE) +
+ global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE);
+ available += reclaimable - min(reclaimable / 2, wmark_low);
if (available < 0)
available = 0;