From b7108d66318abf3e060c7839eabcba52e9461568 Mon Sep 17 00:00:00 2001 From: Charan Teja Kalla Date: Wed, 9 Aug 2023 13:35:44 +0530 Subject: [PATCH] Multi-gen LRU: skip CMA pages when they are not eligible This patch is based on the commit 5da226dbfce3("mm: skip CMA pages when they are not available") which skips cma pages reclaim when they are not eligible for the current allocation context. In mglru, such pages are added to the tail of the immediate generation to maintain better LRU order, which is unlike the case of conventional LRU where such pages are directly added to the head of the LRU list(akin to adding to head of the youngest generation in mglru). No observable issue without this patch on MGLRU, but logically it make sense to skip the CMA page reclaim when those pages can't be satisfied for the current allocation context. Link: https://lkml.kernel.org/r/1691568344-13475-1-git-send-email-quic_charante@quicinc.com Fixes: ac35a4902374 ("mm: multi-gen LRU: minimal implementation") Signed-off-by: Charan Teja Kalla Reviewed-by: Kalesh Singh Cc: David Hildenbrand Cc: Suren Baghdasaryan Cc: Yu Zhao Cc: Zhaoyang Huang Signed-off-by: Andrew Morton --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index b4329f93a682..6cbe921ef662 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4943,7 +4943,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, struct scan_c } /* ineligible */ - if (zone > sc->reclaim_idx) { + if (zone > sc->reclaim_idx || skip_cma(folio, sc)) { gen = folio_inc_gen(lruvec, folio, false); list_move_tail(&folio->lru, &lrugen->folios[gen][type][zone]); return true;