From: Hugh Dickins Date: Wed, 22 Mar 2006 08:08:29 +0000 (-0800) Subject: [PATCH] remove VM_DONTCOPY bogosities X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a6f563db09c54c80d80e9013182dc512a5e53d0f;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [PATCH] remove VM_DONTCOPY bogosities Now that it's madvisable, remove two pieces of VM_DONTCOPY bogosity: 1. There was and is no logical reason why VM_DONTCOPY should be in the list of flags which forbid vma merging (and those drivers which set it are also setting VM_IO, which itself forbids the merge). 2. It's hard to understand the purpose of the VM_HUGETLB, VM_DONTCOPY block in vm_stat_account: but never mind, it's under CONFIG_HUGETLB, which (unlike CONFIG_HUGETLB_PAGE or CONFIG_HUGETLBFS) has never been defined. Signed-off-by: Hugh Dickins Cc: William Lee Irwin III Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/mmap.c b/mm/mmap.c index 47556d2b3e90..0eb9894db6de 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -612,7 +612,7 @@ again: remove_next = 1 + (end > next->vm_end); * If the vma has a ->close operation then the driver probably needs to release * per-vma resources, so we don't attempt to merge those. */ -#define VM_SPECIAL (VM_IO | VM_DONTCOPY | VM_DONTEXPAND | VM_RESERVED | VM_PFNMAP) +#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_RESERVED | VM_PFNMAP) static inline int is_mergeable_vma(struct vm_area_struct *vma, struct file *file, unsigned long vm_flags) @@ -845,14 +845,6 @@ void vm_stat_account(struct mm_struct *mm, unsigned long flags, const unsigned long stack_flags = VM_STACK_FLAGS & (VM_GROWSUP|VM_GROWSDOWN); -#ifdef CONFIG_HUGETLB - if (flags & VM_HUGETLB) { - if (!(flags & VM_DONTCOPY)) - mm->shared_vm += pages; - return; - } -#endif /* CONFIG_HUGETLB */ - if (file) { mm->shared_vm += pages; if ((flags & (VM_EXEC|VM_WRITE)) == VM_EXEC)