From c389a250ab4cfa4a3775d9f2c45271618af6d5b2 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Thu, 14 Nov 2013 14:30:59 -0800 Subject: [PATCH] mm, thp: do not access mm->pmd_huge_pte directly Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov Tested-by: Alex Thorlton Cc: Alex Thorlton Cc: Ingo Molnar Cc: Naoya Horiguchi Cc: "Eric W . Biederman" Cc: "Paul E . McKenney" Cc: Al Viro Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Dave Hansen Cc: Dave Jones Cc: David Howells Cc: Frederic Weisbecker Cc: Johannes Weiner Cc: Kees Cook Cc: Mel Gorman Cc: Michael Kerrisk Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Rik van Riel Cc: Robin Holt Cc: Sedat Dilek Cc: Srikar Dronamraju Cc: Thomas Gleixner Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/mm/pgtable.c | 12 ++++++------ arch/sparc/mm/tlb.c | 12 ++++++------ include/linux/mm.h | 1 + mm/pgtable-generic.c | 12 ++++++------ 4 files changed, 19 insertions(+), 18 deletions(-) diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 0a2e5e086749..1ea18fcfa211 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -1244,11 +1244,11 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, assert_spin_locked(&mm->page_table_lock); /* FIFO */ - if (!mm->pmd_huge_pte) + if (!pmd_huge_pte(mm, pmdp)) INIT_LIST_HEAD(lh); else - list_add(lh, (struct list_head *) mm->pmd_huge_pte); - mm->pmd_huge_pte = pgtable; + list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp)); + pmd_huge_pte(mm, pmdp) = pgtable; } pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) @@ -1260,12 +1260,12 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) assert_spin_locked(&mm->page_table_lock); /* FIFO */ - pgtable = mm->pmd_huge_pte; + pgtable = pmd_huge_pte(mm, pmdp); lh = (struct list_head *) pgtable; if (list_empty(lh)) - mm->pmd_huge_pte = NULL; + pmd_huge_pte(mm, pmdp) = NULL; else { - mm->pmd_huge_pte = (pgtable_t) lh->next; + pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next; list_del(lh); } ptep = (pte_t *) pgtable; diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c index 7a91f288c708..656cc46a81f5 100644 --- a/arch/sparc/mm/tlb.c +++ b/arch/sparc/mm/tlb.c @@ -196,11 +196,11 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, assert_spin_locked(&mm->page_table_lock); /* FIFO */ - if (!mm->pmd_huge_pte) + if (!pmd_huge_pte(mm, pmdp)) INIT_LIST_HEAD(lh); else - list_add(lh, (struct list_head *) mm->pmd_huge_pte); - mm->pmd_huge_pte = pgtable; + list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp)); + pmd_huge_pte(mm, pmdp) = pgtable; } pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) @@ -211,12 +211,12 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) assert_spin_locked(&mm->page_table_lock); /* FIFO */ - pgtable = mm->pmd_huge_pte; + pgtable = pmd_huge_pte(mm, pmdp); lh = (struct list_head *) pgtable; if (list_empty(lh)) - mm->pmd_huge_pte = NULL; + pmd_huge_pte(mm, pmdp) = NULL; else { - mm->pmd_huge_pte = (pgtable_t) lh->next; + pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next; list_del(lh); } pte_val(pgtable[0]) = 0; diff --git a/include/linux/mm.h b/include/linux/mm.h index 4f4ca41fcf27..861cad53b744 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1383,6 +1383,7 @@ static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) return &mm->page_table_lock; } +#define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte) static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) { diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 3929a40bd6c0..41fee3e5d570 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -154,11 +154,11 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, assert_spin_locked(&mm->page_table_lock); /* FIFO */ - if (!mm->pmd_huge_pte) + if (!pmd_huge_pte(mm, pmdp)) INIT_LIST_HEAD(&pgtable->lru); else - list_add(&pgtable->lru, &mm->pmd_huge_pte->lru); - mm->pmd_huge_pte = pgtable; + list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru); + pmd_huge_pte(mm, pmdp) = pgtable; } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif @@ -173,11 +173,11 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) assert_spin_locked(&mm->page_table_lock); /* FIFO */ - pgtable = mm->pmd_huge_pte; + pgtable = pmd_huge_pte(mm, pmdp); if (list_empty(&pgtable->lru)) - mm->pmd_huge_pte = NULL; + pmd_huge_pte(mm, pmdp) = NULL; else { - mm->pmd_huge_pte = list_entry(pgtable->lru.next, + pmd_huge_pte(mm, pmdp) = list_entry(pgtable->lru.next, struct page, lru); list_del(&pgtable->lru); } -- 2.25.1