4.14-stable review patch. If anyone has any objections, please let me know.
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From: Roman Gushchin guro@fb.com
commit eb59254608bc1d42c4c6afdcdce9c0d3ce02b318 upstream.
Patch series "indirectly reclaimable memory", v2.
This patchset introduces the concept of indirectly reclaimable memory and applies it to fix the issue of when a big number of dentries with external names can significantly affect the MemAvailable value.
This patch (of 3):
Introduce a concept of indirectly reclaimable memory and adds the corresponding memory counter and /proc/vmstat item.
Indirectly reclaimable memory is any sort of memory, used by the kernel (except of reclaimable slabs), which is actually reclaimable, i.e. will be released under memory pressure.
The counter is in bytes, as it's not always possible to count such objects in pages. The name contains BYTES by analogy to NR_KERNEL_STACK_KB.
Link: http://lkml.kernel.org/r/20180305133743.12746-2-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
--- include/linux/mmzone.h | 1 + mm/vmstat.c | 1 + 2 files changed, 2 insertions(+)
--- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -180,6 +180,7 @@ enum node_stat_item { NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */ NR_DIRTIED, /* page dirtyings since bootup */ NR_WRITTEN, /* page writings since bootup */ + NR_INDIRECTLY_RECLAIMABLE_BYTES, /* measured in bytes */ NR_VM_NODE_STAT_ITEMS };
--- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1090,6 +1090,7 @@ const char * const vmstat_text[] = { "nr_vmscan_immediate_reclaim", "nr_dirtied", "nr_written", + "nr_indirectly_reclaimable",
/* enum writeback_stat_item counters */ "nr_dirty_threshold",