From: Liu Shixin liushixin2@huawei.com
[ Upstream commit f7ec104458e00d27a190348ac3a513f3df3699a4 ]
commit f63661566fad ("mm/page_alloc.c: clear out zone->lowmem_reserve[] if the zone is empty") clears out zone->lowmem_reserve[] if zone is empty. But when zone is not empty and sysctl_lowmem_reserve_ratio[i] is set to zero, zone_managed_pages(zone) is not counted in the managed_pages either. This is inconsistent with the description of lowmem_reserve, so fix it.
Link: https://lkml.kernel.org/r/20210527125707.3760259-1-liushixin2@huawei.com Fixes: f63661566fad ("mm/page_alloc.c: clear out zone->lowmem_reserve[] if the zone is empty") Signed-off-by: Liu Shixin liushixin2@huawei.com Reported-by: yangerkun yangerkun@huawei.com Reviewed-by: Baoquan He bhe@redhat.com Acked-by: David Hildenbrand david@redhat.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- mm/page_alloc.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 25c83640d47a..382af5377274 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7894,14 +7894,14 @@ static void setup_per_zone_lowmem_reserve(void) unsigned long managed_pages = 0;
for (j = i + 1; j < MAX_NR_ZONES; j++) { - if (clear) { - zone->lowmem_reserve[j] = 0; - } else { - struct zone *upper_zone = &pgdat->node_zones[j]; + struct zone *upper_zone = &pgdat->node_zones[j]; + + managed_pages += zone_managed_pages(upper_zone);
- managed_pages += zone_managed_pages(upper_zone); + if (clear) + zone->lowmem_reserve[j] = 0; + else zone->lowmem_reserve[j] = managed_pages / ratio; - } } } }