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author | Kefeng Wang <wangkefeng.wang@huawei.com> | 2023-09-13 11:51:30 +0200 |
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committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-04 19:32:28 +0200 |
commit | b426ed7889be80359cb4edef142e5c5fa697b068 (patch) | |
tree | 3d79fb3f46dbac0af7d225162cb19f2a4f3c221a /mm/migrate.c | |
parent | mm: migrate: use a folio in add_page_for_migration() (diff) | |
download | linux-b426ed7889be80359cb4edef142e5c5fa697b068.tar.xz linux-b426ed7889be80359cb4edef142e5c5fa697b068.zip |
mm: migrate: remove PageHead() check for HugeTLB in add_page_for_migration()
There is some different between hugeTLB and THP behave when passed the
address of a tail page, for THP, it will migrate the entire THP page, but
for HugeTLB, it will return -EACCES, or -ENOENT before commit e66f17ff7177
("mm/hugetlb: take page table lock in follow_huge_pmd()"),
-EACCES The page is mapped by multiple processes and can be moved
only if MPOL_MF_MOVE_ALL is specified.
-ENOENT The page is not present.
But when check manual[1], both of the two errnos are not suitable, it is
better to keep the same behave between hugetlb and THP when passed the
address of a tail page, so let's just remove the PageHead() check for
HugeTLB.
[1] https://man7.org/linux/man-pages/man2/move_pages.2.html
Link: https://lkml.kernel.org/r/20230913095131.2426871-8-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Suggested-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/migrate.c')
-rw-r--r-- | mm/migrate.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index ce01d03e635a..8495e7e02dd4 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2096,10 +2096,8 @@ static int add_page_for_migration(struct mm_struct *mm, const void __user *p, goto out_putfolio; if (folio_test_hugetlb(folio)) { - if (PageHead(page)) { - isolated = isolate_hugetlb(folio, pagelist); - err = isolated ? 1 : -EBUSY; - } + isolated = isolate_hugetlb(folio, pagelist); + err = isolated ? 1 : -EBUSY; } else { isolated = folio_isolate_lru(folio); if (!isolated) { |