mm: delete NR_PAGES_SCANNED and pgdat_reclaimable()
NR_PAGES_SCANNED counts number of pages scanned since the last page free
event in the allocator. This was used primarily to measure the
reclaimability of zones and nodes, and determine when reclaim should
give up on them. In that role, it has been replaced in the preceding
patches by a different mechanism.
Being implemented as an efficient vmstat counter, it was automatically
exported to userspace as well. It's however unlikely that anyone
outside the kernel is using this counter in any meaningful way.
Remove the counter and the unused pgdat_reclaimable().
Link: http://lkml.kernel.org/r/20170228214007.5621-8-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Jia He <hejianet@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmstat.c b/mm/vmstat.c
index baee70d..c8d1505 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -954,7 +954,6 @@
"nr_unevictable",
"nr_isolated_anon",
"nr_isolated_file",
- "nr_pages_scanned",
"workingset_refault",
"workingset_activate",
"workingset_nodereclaim",
@@ -1378,7 +1377,6 @@
"\n min %lu"
"\n low %lu"
"\n high %lu"
- "\n node_scanned %lu"
"\n spanned %lu"
"\n present %lu"
"\n managed %lu",
@@ -1386,7 +1384,6 @@
min_wmark_pages(zone),
low_wmark_pages(zone),
high_wmark_pages(zone),
- node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED),
zone->spanned_pages,
zone->present_pages,
zone->managed_pages);
@@ -1586,22 +1583,9 @@
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
val = atomic_long_read(&vm_zone_stat[i]);
if (val < 0) {
- switch (i) {
- case NR_PAGES_SCANNED:
- /*
- * This is often seen to go negative in
- * recent kernels, but not to go permanently
- * negative. Whilst it would be nicer not to
- * have exceptions, rooting them out would be
- * another task, of rather low priority.
- */
- break;
- default:
- pr_warn("%s: %s %ld\n",
- __func__, vmstat_text[i], val);
- err = -EINVAL;
- break;
- }
+ pr_warn("%s: %s %ld\n",
+ __func__, vmstat_text[i], val);
+ err = -EINVAL;
}
}
if (err)