The patch titled
Subject: mm/migration: return errno when isolate_huge_page failed
has been added to the -mm tree. Its filename is
mm-migration-return-errno-when-isolate_huge_page-failed.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-migration-return-errno-when-isolate_huge_page-failed.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-migration-return-errno-when-isolate_huge_page-failed.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm/migration: return errno when isolate_huge_page failed
We might fail to isolate huge page due to e.g. the page is under
migration which cleared HPageMigratable. So we should return -EBUSY in
this case rather than always return 1 which could confuse the user. Also
we make the prototype of isolate_huge_page consistent with
isolate_lru_page to improve the readability.
Link: https://lkml.kernel.org/r/20220425132723.34824-4-linmiaohe@xxxxxxxxxx
Fixes: e8db67eb0ded ("mm: migrate: move_pages() supports thp migration")
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Suggested-by: Huang Ying <ying.huang@xxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/hugetlb.h | 6 +++---
mm/gup.c | 2 +-
mm/hugetlb.c | 11 +++++------
mm/memory-failure.c | 2 +-
mm/mempolicy.c | 2 +-
mm/migrate.c | 5 +++--
6 files changed, 14 insertions(+), 14 deletions(-)
--- a/include/linux/hugetlb.h~mm-migration-return-errno-when-isolate_huge_page-failed
+++ a/include/linux/hugetlb.h
@@ -170,7 +170,7 @@ bool hugetlb_reserve_pages(struct inode
vm_flags_t vm_flags);
long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
long freed);
-bool isolate_huge_page(struct page *page, struct list_head *list);
+int isolate_huge_page(struct page *page, struct list_head *list);
int get_hwpoison_huge_page(struct page *page, bool *hugetlb);
int get_huge_page_for_hwpoison(unsigned long pfn, int flags);
void putback_active_hugepage(struct page *page);
@@ -376,9 +376,9 @@ static inline pte_t *huge_pte_offset(str
return NULL;
}
-static inline bool isolate_huge_page(struct page *page, struct list_head *list)
+static inline int isolate_huge_page(struct page *page, struct list_head *list)
{
- return false;
+ return -EBUSY;
}
static inline int get_hwpoison_huge_page(struct page *page, bool *hugetlb)
--- a/mm/gup.c~mm-migration-return-errno-when-isolate_huge_page-failed
+++ a/mm/gup.c
@@ -1869,7 +1869,7 @@ static long check_and_migrate_movable_pa
* Try to move out any movable page before pinning the range.
*/
if (folio_test_hugetlb(folio)) {
- if (!isolate_huge_page(&folio->page,
+ if (isolate_huge_page(&folio->page,
&movable_page_list))
isolation_error_count++;
continue;
--- a/mm/hugetlb.c~mm-migration-return-errno-when-isolate_huge_page-failed
+++ a/mm/hugetlb.c
@@ -2765,8 +2765,7 @@ retry:
* Fail with -EBUSY if not possible.
*/
spin_unlock_irq(&hugetlb_lock);
- if (!isolate_huge_page(old_page, list))
- ret = -EBUSY;
+ ret = isolate_huge_page(old_page, list);
spin_lock_irq(&hugetlb_lock);
goto free_new;
} else if (!HPageFreed(old_page)) {
@@ -2842,7 +2841,7 @@ int isolate_or_dissolve_huge_page(struct
if (hstate_is_gigantic(h))
return -ENOMEM;
- if (page_count(head) && isolate_huge_page(head, list))
+ if (page_count(head) && !isolate_huge_page(head, list))
ret = 0;
else if (!page_count(head))
ret = alloc_and_dissolve_huge_page(h, head, list);
@@ -6932,15 +6931,15 @@ follow_huge_pgd(struct mm_struct *mm, un
return pte_page(*(pte_t *)pgd) + ((address & ~PGDIR_MASK) >> PAGE_SHIFT);
}
-bool isolate_huge_page(struct page *page, struct list_head *list)
+int isolate_huge_page(struct page *page, struct list_head *list)
{
- bool ret = true;
+ int ret = 0;
spin_lock_irq(&hugetlb_lock);
if (!PageHeadHuge(page) ||
!HPageMigratable(page) ||
!get_page_unless_zero(page)) {
- ret = false;
+ ret = -EBUSY;
goto unlock;
}
ClearHPageMigratable(page);
--- a/mm/memory-failure.c~mm-migration-return-errno-when-isolate_huge_page-failed
+++ a/mm/memory-failure.c
@@ -2203,7 +2203,7 @@ static bool isolate_page(struct page *pa
bool lru = PageLRU(page);
if (PageHuge(page)) {
- isolated = isolate_huge_page(page, pagelist);
+ isolated = !isolate_huge_page(page, pagelist);
} else {
if (lru)
isolated = !isolate_lru_page(page);
--- a/mm/mempolicy.c~mm-migration-return-errno-when-isolate_huge_page-failed
+++ a/mm/mempolicy.c
@@ -602,7 +602,7 @@ static int queue_pages_hugetlb(pte_t *pt
/* With MPOL_MF_MOVE, we migrate only unshared hugepage. */
if (flags & (MPOL_MF_MOVE_ALL) ||
(flags & MPOL_MF_MOVE && page_mapcount(page) == 1)) {
- if (!isolate_huge_page(page, qp->pagelist) &&
+ if (isolate_huge_page(page, qp->pagelist) &&
(flags & MPOL_MF_STRICT))
/*
* Failed to isolate page but allow migrating pages
--- a/mm/migrate.c~mm-migration-return-errno-when-isolate_huge_page-failed
+++ a/mm/migrate.c
@@ -1628,8 +1628,9 @@ static int add_page_for_migration(struct
if (PageHuge(page)) {
if (PageHead(page)) {
- isolate_huge_page(page, pagelist);
- err = 1;
+ err = isolate_huge_page(page, pagelist);
+ if (!err)
+ err = 1;
}
} else {
struct page *head;
_
Patches currently in -mm which might be from linmiaohe@xxxxxxxxxx are
mm-shmem-make-shmem_init-return-void.patch
mm-memcg-remove-unneeded-nr_scanned.patch
mm-mmapc-use-helper-mlock_future_check.patch
mm-mremap-use-helper-mlock_future_check.patch
mm-mremap-avoid-unneeded-do_munmap-call.patch
mm-memory-failurec-minor-cleanup-for-hwpoisonhandlable.patch
mm-memory-failurec-dissolve-truncated-hugetlb-page.patch
mm-vmscan-remove-obsolete-comment-in-get_scan_count.patch
mm-vmscan-fix-comment-for-current_may_throttle.patch
mm-vmscan-fix-comment-for-isolate_lru_pages.patch
mm-z3fold-declare-z3fold_mount-with-__init.patch
mm-z3fold-remove-obsolete-comment-in-z3fold_alloc.patch
mm-z3fold-minor-clean-up-for-z3fold_free.patch
mm-z3fold-remove-unneeded-page_mapcount_reset-and-clearpageprivate.patch
mm-z3fold-remove-confusing-local-variable-l-reassignment.patch
mm-z3fold-move-decrement-of-pool-pages_nr-into-__release_z3fold_page.patch
mm-z3fold-remove-redundant-list_del_init-of-zhdr-buddy-in-z3fold_free.patch
mm-z3fold-remove-unneeded-page_headless-check-in-free_handle.patch
mm-compaction-use-helper-isolation_suitable.patch
drivers-base-nodec-fix-compaction-sysfs-file-leak.patch
mm-mempolicy-clean-up-the-code-logic-in-queue_pages_pte_range.patch
mm-migration-remove-unneeded-local-variable-mapping_locked.patch
mm-migration-remove-unneeded-local-variable-page_lru.patch
mm-migration-use-helper-function-vma_lookup-in-add_page_for_migration.patch
mm-migration-use-helper-macro-min-in-do_pages_stat.patch
mm-migration-avoid-unneeded-nodemask_t-initialization.patch
mm-migration-remove-some-duplicated-codes-in-migrate_pages.patch
mm-migration-fix-potential-page-refcounts-leak-in-migrate_pages.patch
mm-migration-fix-potential-invalid-node-access-for-reclaim-based-migration.patch
mm-migration-fix-possible-do_pages_stat_array-racing-with-memory-offline.patch
mm-madvise-fix-potential-pte_unmap_unlock-pte-error.patch
mm-madvise-free-hwpoison-and-swapin-error-entry-in-madvise_free_pte_range.patch
mm-compaction-remove-unneeded-return-value-of-kcompactd_run.patch
mm-compaction-remove-unneeded-pfn-update.patch
mm-compaction-remove-unneeded-assignment-to-isolate_start_pfn.patch
mm-compaction-clean-up-comment-for-sched-contention.patch
mm-compaction-clean-up-comment-about-suitable-migration-target-recheck.patch
mm-compaction-use-compact_cluster_max-in-compactionc.patch
mm-compaction-use-helper-compound_nr-in-isolate_migratepages_block.patch
mm-compaction-clean-up-comment-about-async-compaction-in-isolate_migratepages.patch
mm-compaction-avoid-possible-null-pointer-dereference-in-kcompactd_cpu_online.patch
mm-compaction-make-compaction_zonelist_suitable-return-false-when-compact_success.patch
mm-compaction-simplify-the-code-in-__compact_finished.patch
mm-compaction-make-sure-highest-is-above-the-min_pfn.patch
mm-swapfile-unuse_pte-can-map-random-data-if-swap-read-fails.patch
mm-swapfile-fix-lost-swap-bits-in-unuse_pte.patch
mm-migration-reduce-the-rcu-lock-duration.patch
mm-migration-remove-unneeded-lock-page-and-pagemovable-check.patch
mm-migration-return-errno-when-isolate_huge_page-failed.patch
mm-migration-fix-potential-pte_unmap-on-an-not-mapped-pte.patch
