From 10969b5571387047cd461a9c701b8b9cd007f6c7 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 3 Oct 2023 02:15:09 -0700 Subject: hugetlbfs: drop shared NUMA mempolicy pretence Patch series "mempolicy: cleanups leading to NUMA mpol without vma", v2. Mostly cleanups in mm/mempolicy.c, but finally removing the pseudo-vma from shmem folio allocation, and removing the mmap_lock around folio migration for mbind and migrate_pages syscalls. This patch (of 12): hugetlbfs_fallocate() goes through the motions of pasting a shared NUMA mempolicy onto its pseudo-vma, but how could there ever be a shared NUMA mempolicy for this file? hugetlb_vm_ops has never offered a set_policy method, and hugetlbfs_parse_param() has never supported any mpol options for a mount-wide default policy. It's just an illusion: clean it away so as not to confuse others, giving us more freedom to adjust shmem's set_policy/get_policy implementation. But hugetlbfs_inode_info is still required, just to accommodate seals. Yes, shared NUMA mempolicy support could be added to hugetlbfs, with a set_policy method and/or mpol mount option (Andi's first posting did include an admitted-unsatisfactory hugetlb_set_policy()); but it seems that nobody has bothered to add that in the nineteen years since v2.6.7 made it possible, and there is at least one company that has invested enough into hugetlbfs, that I guess they have learnt well enough how to manage its NUMA, without needing shared mempolicy. Remove linux/mempolicy.h from linux/hugetlb.h: include linux/pagemap.h in its place, because hugetlb.h's recently added use of filemap_lock_folio() requires that (although most .configs and .c's get it in some other way). Link: https://lkml.kernel.org/r/ebc0987e-beff-8bfb-9283-234c2cbd17c5@google.com Link: https://lkml.kernel.org/r/cae82d4b-904a-faaf-282a-34fcc188c81f@google.com Signed-off-by: Hugh Dickins Reviewed-by: Matthew Wilcox (Oracle) Cc: Andi Kleen Cc: Christoph Lameter Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "Huang, Ying" Cc: Kefeng Wang Cc: Mel Gorman Cc: Michal Hocko Cc: Mike Kravetz Cc: Sidhartha Kumar Cc: Suren Baghdasaryan Cc: Tejun heo Cc: Vishal Moola (Oracle) Cc: Yang Shi Cc: Nhat Pham Cc: Yosry Ahmed Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 205469aa0613..158ff156710b 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -30,7 +30,7 @@ void free_huge_folio(struct folio *folio); #ifdef CONFIG_HUGETLB_PAGE -#include +#include #include #include @@ -545,7 +545,6 @@ static inline struct hugetlbfs_sb_info *HUGETLBFS_SB(struct super_block *sb) } struct hugetlbfs_inode_info { - struct shared_policy policy; struct inode vfs_inode; unsigned int seals; }; -- cgit v1.2.3