[PATCH v2 21/29] mm: rename PG_isolated to PG_movable_ops_isolated
From: David Hildenbrand <hidden>
Date: 2025-07-04 10:26:32
Also in:
linux-doc, linux-fsdevel, linux-mm, linuxppc-dev, lkml
Subsystem:
memory management, memory management - memory policy and migration, memory management - page allocator, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Vlastimil Babka, Linus Torvalds
Let's rename the flag to make it clearer where it applies (not folios ...). While at it, define the flag only with CONFIG_MIGRATION. Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Lorenzo Stoakes <redacted> Reviewed-by: Harry Yoo <redacted> Signed-off-by: David Hildenbrand <redacted> --- include/linux/page-flags.h | 16 +++++++++++----- mm/compaction.c | 2 +- mm/migrate.c | 14 +++++++------- 3 files changed, 19 insertions(+), 13 deletions(-)
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 5f2b570735852..8b0e5c7371e67 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h@@ -167,10 +167,9 @@ enum pageflags { /* Remapped by swiotlb-xen. */ PG_xen_remapped = PG_owner_priv_1, - /* non-lru isolated movable page */ - PG_isolated = PG_reclaim, - #ifdef CONFIG_MIGRATION + /* movable_ops page that is isolated for migration */ + PG_movable_ops_isolated = PG_reclaim, /* this is a movable_ops page (for selected typed pages only) */ PG_movable_ops = PG_uptodate, #endif
@@ -1126,8 +1125,6 @@ static inline bool folio_contain_hwpoisoned_page(struct folio *folio) bool is_free_buddy_page(const struct page *page); -PAGEFLAG(Isolated, isolated, PF_ANY); - #ifdef CONFIG_MIGRATION /* * This page is migratable through movable_ops (for selected typed pages
@@ -1147,9 +1144,18 @@ PAGEFLAG(Isolated, isolated, PF_ANY); */ TESTPAGEFLAG(MovableOps, movable_ops, PF_NO_TAIL); SETPAGEFLAG(MovableOps, movable_ops, PF_NO_TAIL); +/* + * A movable_ops page has this flag set while it is isolated for migration. + * This flag primarily protects against concurrent migration attempts. + * + * Once migration ended (success or failure), the flag is cleared. The + * flag is managed by the migration core. + */ +PAGEFLAG(MovableOpsIsolated, movable_ops_isolated, PF_NO_TAIL); #else /* !CONFIG_MIGRATION */ TESTPAGEFLAG_FALSE(MovableOps, movable_ops); SETPAGEFLAG_NOOP(MovableOps, movable_ops); +PAGEFLAG_FALSE(MovableOpsIsolated, movable_ops_isolated); #endif /* CONFIG_MIGRATION */ /**
diff --git a/mm/compaction.c b/mm/compaction.c
index 349f4ea0ec3e5..bf021b31c7ece 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c@@ -1051,7 +1051,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, if (!PageLRU(page)) { /* Isolation code will deal with any races. */ if (unlikely(page_has_movable_ops(page)) && - !PageIsolated(page)) { + !PageMovableOpsIsolated(page)) { if (locked) { unlock_page_lruvec_irqrestore(locked, flags); locked = NULL;
diff --git a/mm/migrate.c b/mm/migrate.c
index fde6221562399..7fd3d38410c42 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c@@ -135,7 +135,7 @@ bool isolate_movable_ops_page(struct page *page, isolate_mode_t mode) goto out_putfolio; VM_WARN_ON_ONCE_PAGE(!page_has_movable_ops(page), page); - if (PageIsolated(page)) + if (PageMovableOpsIsolated(page)) goto out_no_isolated; mops = page_movable_ops(page);
@@ -146,8 +146,8 @@ bool isolate_movable_ops_page(struct page *page, isolate_mode_t mode) goto out_no_isolated; /* Driver shouldn't use the isolated flag */ - VM_WARN_ON_ONCE_PAGE(PageIsolated(page), page); - SetPageIsolated(page); + VM_WARN_ON_ONCE_PAGE(PageMovableOpsIsolated(page), page); + SetPageMovableOpsIsolated(page); folio_unlock(folio); return true;
@@ -177,10 +177,10 @@ static void putback_movable_ops_page(struct page *page) struct folio *folio = page_folio(page); VM_WARN_ON_ONCE_PAGE(!page_has_movable_ops(page), page); - VM_WARN_ON_ONCE_PAGE(!PageIsolated(page), page); + VM_WARN_ON_ONCE_PAGE(!PageMovableOpsIsolated(page), page); folio_lock(folio); page_movable_ops(page)->putback_page(page); - ClearPageIsolated(page); + ClearPageMovableOpsIsolated(page); folio_unlock(folio); folio_put(folio); }
@@ -216,10 +216,10 @@ static int migrate_movable_ops_page(struct page *dst, struct page *src, int rc = MIGRATEPAGE_SUCCESS; VM_WARN_ON_ONCE_PAGE(!page_has_movable_ops(src), src); - VM_WARN_ON_ONCE_PAGE(!PageIsolated(src), src); + VM_WARN_ON_ONCE_PAGE(!PageMovableOpsIsolated(src), src); rc = page_movable_ops(src)->migrate_page(dst, src, mode); if (rc == MIGRATEPAGE_SUCCESS) - ClearPageIsolated(src); + ClearPageMovableOpsIsolated(src); return rc; }
--
2.49.0