From 314e51b9851b4f4e8ab302243ff5a6fc6147f379 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Mon, 8 Oct 2012 16:29:02 -0700 Subject: mm: kill vma flag VM_RESERVED and mm->reserved_vm counter A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA, currently it lost original meaning but still has some effects: | effect | alternative flags -+------------------------+--------------------------------------------- 1| account as reserved_vm | VM_IO 2| skip in core dump | VM_IO, VM_DONTDUMP 3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP 4| do not mlock | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP This patch removes reserved_vm counter from mm_struct. Seems like nobody cares about it, it does not exported into userspace directly, it only reduces total_vm showed in proc. Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP. remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP. remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP. [akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup] Signed-off-by: Konstantin Khlebnikov Cc: Alexander Viro Cc: Carsten Otte Cc: Chris Metcalf Cc: Cyrill Gorcunov Cc: Eric Paris Cc: H. Peter Anvin Cc: Hugh Dickins Cc: Ingo Molnar Cc: James Morris Cc: Jason Baron Cc: Kentaro Takeda Cc: Matt Helsley Cc: Nick Piggin Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Robert Richter Cc: Suresh Siddha Cc: Tetsuo Handa Cc: Venkatesh Pallipadi Acked-by: Linus Torvalds Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/ksm.c | 3 +-- mm/memory.c | 11 +++++------ mm/mlock.c | 2 +- mm/mmap.c | 2 -- mm/nommu.c | 2 +- mm/vmalloc.c | 3 +-- 6 files changed, 9 insertions(+), 14 deletions(-) (limited to 'mm') diff --git a/mm/ksm.c b/mm/ksm.c index f9ccb16..9638620 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -1469,8 +1469,7 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start, */ if (*vm_flags & (VM_MERGEABLE | VM_SHARED | VM_MAYSHARE | VM_PFNMAP | VM_IO | VM_DONTEXPAND | - VM_RESERVED | VM_HUGETLB | - VM_NONLINEAR | VM_MIXEDMAP)) + VM_HUGETLB | VM_NONLINEAR | VM_MIXEDMAP)) return 0; /* just ignore the advice */ #ifdef VM_SAO diff --git a/mm/memory.c b/mm/memory.c index 7b1e4fe..e09c048 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2297,14 +2297,13 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, * rest of the world about it: * VM_IO tells people not to look at these pages * (accesses can have side effects). - * VM_RESERVED is specified all over the place, because - * in 2.4 it kept swapout's vma scan off this vma; but - * in 2.6 the LRU scan won't even find its pages, so this - * flag means no more than count its pages in reserved_vm, - * and omit it from core dump, even when VM_IO turned off. * VM_PFNMAP tells the core MM that the base pages are just * raw PFN mappings, and do not have a "struct page" associated * with them. + * VM_DONTEXPAND + * Disable vma merging and expanding with mremap(). + * VM_DONTDUMP + * Omit vma from core dump, even when VM_IO turned off. * * There's a horrible special case to handle copy-on-write * behaviour that some programs depend on. We mark the "original" @@ -2321,7 +2320,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, if (err) return -EINVAL; - vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP; + vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; BUG_ON(addr >= end); pfn -= addr >> PAGE_SHIFT; diff --git a/mm/mlock.c b/mm/mlock.c index ef726e8..a948be4 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -227,7 +227,7 @@ long mlock_vma_pages_range(struct vm_area_struct *vma, if (vma->vm_flags & (VM_IO | VM_PFNMAP)) goto no_mlock; - if (!((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) || + if (!((vma->vm_flags & VM_DONTEXPAND) || is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm))) { diff --git a/mm/mmap.c b/mm/mmap.c index c1ad2e78..a76042d 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -945,8 +945,6 @@ void vm_stat_account(struct mm_struct *mm, unsigned long flags, mm->exec_vm += pages; } else if (flags & stack_flags) mm->stack_vm += pages; - if (flags & (VM_RESERVED|VM_IO)) - mm->reserved_vm += pages; } #endif /* CONFIG_PROC_FS */ diff --git a/mm/nommu.c b/mm/nommu.c index 9c4a7b6..12e84e6 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1811,7 +1811,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, if (addr != (pfn << PAGE_SHIFT)) return -EINVAL; - vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP; + vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; return 0; } EXPORT_SYMBOL(remap_pfn_range); diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 2bb90b1..8de7046 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2163,8 +2163,7 @@ int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, usize -= PAGE_SIZE; } while (usize > 0); - /* Prevent "things" like memory migration? VM_flags need a cleanup... */ - vma->vm_flags |= VM_RESERVED; + vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; return 0; } -- cgit v1.1