From d2081b2bf8195b8239c67fdd61518e077da7cbec Mon Sep 17 00:00:00 2001 From: Yang Shi Date: Thu, 19 May 2022 14:08:49 -0700 Subject: mm: khugepaged: make khugepaged_enter() void function The most callers of khugepaged_enter() don't care about the return value. Only dup_mmap(), anonymous THP page fault and MADV_HUGEPAGE handle the error by returning -ENOMEM. Actually it is not harmful for them to ignore the error case either. It also sounds overkilling to fail fork() and page fault early due to khugepaged_enter() error, and MADV_HUGEPAGE does set VM_HUGEPAGE flag regardless of the error. Link: https://lkml.kernel.org/r/20220510203222.24246-6-shy828301@gmail.com Signed-off-by: Yang Shi Acked-by: Song Liu Acked-by: Vlastmil Babka Cc: Kirill A. Shutemov Cc: Matthew Wilcox (Oracle) Cc: Miaohe Lin Cc: Rik van Riel Cc: Song Liu Cc: Theodore Ts'o Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/khugepaged.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) (limited to 'mm/khugepaged.c') diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 1f4822dcc970..b43b294ca5f8 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -365,8 +365,7 @@ int hugepage_madvise(struct vm_area_struct *vma, * register it here without waiting a page fault that * may not happen any time soon. */ - if (khugepaged_enter_vma_merge(vma, *vm_flags)) - return -ENOMEM; + khugepaged_enter_vma_merge(vma, *vm_flags); break; case MADV_NOHUGEPAGE: *vm_flags &= ~VM_HUGEPAGE; @@ -475,20 +474,20 @@ static bool hugepage_vma_check(struct vm_area_struct *vma, return true; } -int __khugepaged_enter(struct mm_struct *mm) +void __khugepaged_enter(struct mm_struct *mm) { struct mm_slot *mm_slot; int wakeup; mm_slot = alloc_mm_slot(); if (!mm_slot) - return -ENOMEM; + return; /* __khugepaged_exit() must not run from under us */ VM_BUG_ON_MM(khugepaged_test_exit(mm), mm); if (unlikely(test_and_set_bit(MMF_VM_HUGEPAGE, &mm->flags))) { free_mm_slot(mm_slot); - return 0; + return; } spin_lock(&khugepaged_mm_lock); @@ -504,11 +503,9 @@ int __khugepaged_enter(struct mm_struct *mm) mmgrab(mm); if (wakeup) wake_up_interruptible(&khugepaged_wait); - - return 0; } -int khugepaged_enter_vma_merge(struct vm_area_struct *vma, +void khugepaged_enter_vma_merge(struct vm_area_struct *vma, unsigned long vm_flags) { unsigned long hstart, hend; @@ -519,13 +516,12 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma, * file-private shmem THP is not supported. */ if (!hugepage_vma_check(vma, vm_flags)) - return 0; + return; hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK; hend = vma->vm_end & HPAGE_PMD_MASK; if (hstart < hend) - return khugepaged_enter(vma, vm_flags); - return 0; + khugepaged_enter(vma, vm_flags); } void __khugepaged_exit(struct mm_struct *mm) -- cgit v1.2.3