diff options
| author | Hugh Dickins <hughd@google.com> | 2022-11-02 18:48:45 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-11-30 15:58:46 -0800 |
| commit | dad6a5eb55564845aa17b8b20fa834af21e46c48 (patch) | |
| tree | 40a8eaceb6a7a7712b4009c0e9020f1c47096ca3 /mm/memory-failure.c | |
| parent | 634ba645f9bc888227ca954ea643579268d1b6d8 (diff) | |
mm,hugetlb: use folio fields in second tail page
Patch series "mm,huge,rmap: unify and speed up compound mapcounts".
This patch (of 3):
We want to declare one more int in the first tail of a compound page: that
first tail page being valuable property, since every compound page has a
first tail, but perhaps no more than that.
No problem on 64-bit: there is already space for it. No problem with
32-bit THPs: 5.18 commit 5232c63f46fd ("mm: Make compound_pincount always
available") kindly cleared the space for it, apparently not realizing that
only 64-bit architectures enable CONFIG_THP_SWAP (whose use of tail
page->private might conflict) - but make sure of that in its Kconfig.
But hugetlb pages use tail page->private of the first tail page for a
subpool pointer, which will conflict; and they also use page->private of
the 2nd, 3rd and 4th tails.
Undo "mm: add private field of first tail to struct page and struct
folio"'s recent addition of private_1 to the folio tail: instead add
hugetlb_subpool, hugetlb_cgroup, hugetlb_cgroup_rsvd, hugetlb_hwpoison to
a second tail page of the folio: THP has long been using several fields of
that tail, so make better use of it for hugetlb too. This is not how a
generic folio should be declared in future, but it is an effective
transitional way to make use of it.
Delete the SUBPAGE_INDEX stuff, but keep __NR_USED_SUBPAGE: now 3.
[hughd@google.com: prefix folio's page_1 and page_2 with double underscore,
give folio's _flags_2 and _head_2 a line documentation each]
Link: https://lkml.kernel.org/r/9e2cb6b-5b58-d3f2-b5ee-5f8a14e8f10@google.com
Link: https://lkml.kernel.org/r/5f52de70-975-e94f-f141-543765736181@google.com
Link: https://lkml.kernel.org/r/3818cc9a-9999-d064-d778-9c94c5911e6@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/memory-failure.c')
| -rw-r--r-- | mm/memory-failure.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 779a426d2cab..63d8501001c6 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1687,8 +1687,7 @@ EXPORT_SYMBOL_GPL(mf_dax_kill_procs); #ifdef CONFIG_HUGETLB_PAGE /* * Struct raw_hwp_page represents information about "raw error page", - * constructing singly linked list originated from ->private field of - * SUBPAGE_INDEX_HWPOISON-th tail page. + * constructing singly linked list from ->_hugetlb_hwpoison field of folio. */ struct raw_hwp_page { struct llist_node node; @@ -1697,7 +1696,7 @@ struct raw_hwp_page { static inline struct llist_head *raw_hwp_list_head(struct page *hpage) { - return (struct llist_head *)&page_private(hpage + SUBPAGE_INDEX_HWPOISON); + return (struct llist_head *)&page_folio(hpage)->_hugetlb_hwpoison; } static unsigned long __free_raw_hwp_pages(struct page *hpage, bool move_flag) |