Re: [PATCH] mm, vmscan: make kswapd unreserve highatomic pageblocks
From: Jose A. Perez de Azpillaga
Date: Wed Nov 04 2026 - 18:39:50 EST
On 11/4/26 7:38 PM, Vlastimil Babka (SUSE) wrote:
> Hook this highatomic unreserve to the moment we are increasing kswapd
> reclaim priority, as that is when kswapd is struggling to make progress
> and it should roughly match the case of direct reclaim failure.
>
isn't raise_priority true after almost every pass at DEF_PRIORITY, stuck
or not?
[snip]
> + if (raise_priority || !nr_reclaimed) {
> + /*
> + * Similarly to when direct reclaim is retrying, try to
> + * unreserve highatomic pageblocks on the node. Convert
> + * them to movable ones as kswapd doesn't have a target
> + * migratetype, and passing unmovable should lead to
> + * least permanent fragmentation.
> + */
> + for (int i = 0; i <= highest_zoneidx; i++) {
> + struct zone *zone = pgdat->node_zones + i;
> +
> + unreserve_highatomic_pageblock_zone(zone,
> + MIGRATE_UNMOVABLE, false);
> + }
s/movable/unmovable/ in the comment?
--
cheers,
jose a. p-a