From 6303d1c553c8d758f068de70a41668622b7a917c Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Wed, 3 Apr 2024 21:47:21 +0800 Subject: [PATCH] mm: page_alloc: use the correct THP order for THP PCP Commit 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists") extends the PCP allocator to store THP pages, and it determines whether to cache THP pages in PCP by comparing with pageblock_order. But the pageblock_order is not always equal to THP order. It might also be MAX_PAGE_ORDER, which could prevent PCP from caching THP pages. Therefore, using HPAGE_PMD_ORDER instead to determine the need for caching THP for PCP will fix this issue Link: https://lkml.kernel.org/r/a25c9e14cd03907d5978b60546a69e6aa3fc2a7d.1712151833.git.baolin.wang@linux.alibaba.com Fixes: 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists") Signed-off-by: Baolin Wang Acked-by: Vlastimil Babka Cc: Mel Gorman Reviewed-by: Barry Song Signed-off-by: Andrew Morton --- mm/page_alloc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 07c21774a7221..cbe3f695eda9b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -506,7 +506,7 @@ static inline unsigned int order_to_pindex(int migratetype, int order) { #ifdef CONFIG_TRANSPARENT_HUGEPAGE if (order > PAGE_ALLOC_COSTLY_ORDER) { - VM_BUG_ON(order != pageblock_order); + VM_BUG_ON(order != HPAGE_PMD_ORDER); return NR_LOWORDER_PCP_LISTS; } #else @@ -522,7 +522,7 @@ static inline int pindex_to_order(unsigned int pindex) #ifdef CONFIG_TRANSPARENT_HUGEPAGE if (pindex == NR_LOWORDER_PCP_LISTS) - order = pageblock_order; + order = HPAGE_PMD_ORDER; #else VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER); #endif @@ -535,7 +535,7 @@ static inline bool pcp_allowed_order(unsigned int order) if (order <= PAGE_ALLOC_COSTLY_ORDER) return true; #ifdef CONFIG_TRANSPARENT_HUGEPAGE - if (order == pageblock_order) + if (order == HPAGE_PMD_ORDER) return true; #endif return false; -- 2.30.2