[Pmem] [PATCH 04/17] anolis: mm: migrate: introduce a standard migration target allocation function

This patch is borrowed from commit b4b382238ed2 ("mm/migrate: move migration helper from .h to .c"), and commit 19fc7bed252c ("mm/migrate: introduce a standard migration target allocation function"), to introduce a new migration allocation function to help to do page demotion. Signed-off-by: Baolin Wang <baolin.wang(a)linux.alibaba.com> --- mm/internal.h | 1 + mm/migrate.c | 41 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+) diff --git a/mm/internal.h b/mm/internal.h index c10af5e..a1e34ed 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -584,4 +584,5 @@ static inline bool is_migrate_highatomic_page(struct page *page) void setup_zone_pageset(struct zone *zone); extern struct page *alloc_new_node_page(struct page *page, unsigned long node); +extern struct page *alloc_migration_target(struct page *page, unsigned long node); #endif /* __MM_INTERNAL_H */ diff --git a/mm/migrate.c b/mm/migrate.c index 7663035..b987231 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1572,6 +1572,47 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, return rc; } +struct page *alloc_migration_target(struct page *page, unsigned long node) +{ + gfp_t gfp_mask; + unsigned int order = 0; + struct page *new_page = NULL; + int nid = node; + int zidx; + + gfp_mask = (GFP_HIGHUSER_MOVABLE & ~__GFP_RECLAIM) | + __GFP_THISNODE | __GFP_NOWARN | + __GFP_NOMEMALLOC | GFP_NOWAIT; + if (nid == NUMA_NO_NODE) + nid = page_to_nid(page); + + if (PageHuge(page)) { + struct hstate *h = page_hstate(compound_head(page)); + return alloc_huge_page_nodemask(h, nid, NULL); + } + + if (PageTransHuge(page)) { + /* + * clear __GFP_RECLAIM to make the migration callback + * consistent with regular THP allocations. + */ + gfp_mask &= ~__GFP_RECLAIM; + gfp_mask |= GFP_TRANSHUGE; + order = HPAGE_PMD_ORDER; + } + + zidx = zone_idx(page_zone(page)); + if (is_highmem_idx(zidx) || zidx == ZONE_MOVABLE) + gfp_mask |= __GFP_HIGHMEM; + + new_page = __alloc_pages_nodemask(gfp_mask, order, nid, NULL); + + if (new_page && PageTransHuge(new_page)) + prep_transhuge_page(new_page); + + return new_page; +} + #ifdef CONFIG_NUMA static int store_status(int __user *status, int start, int value, int nr) -- 1.8.3.1