mm: kill vma flag VM_RESERVED and mm->reserved_vm counter (314e51b9) · Commits · 戴 / test

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 <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by:

Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

Documentation/vm/unevictable-lru.txt

+2 −2

Original line number	Diff line number	Diff line
		@@ -371,8 +371,8 @@ mlock_fixup() filters several classes of "special" VMAs:
		mlock_fixup() will call make_pages_present() in the hugetlbfs VMA range to
		allocate the huge pages and populate the ptes.

		3) VMAs with VM_DONTEXPAND or VM_RESERVED are generally userspace mappings of
		kernel pages, such as the VDSO page, relay channel pages, etc. These pages
		3) VMAs with VM_DONTEXPAND are generally userspace mappings of kernel pages,
		such as the VDSO page, relay channel pages, etc. These pages
		are inherently unevictable and are not managed on the LRU lists.
		mlock_fixup() treats these VMAs the same as hugetlbfs VMAs. It calls
		make_pages_present() to populate the ptes.

arch/alpha/kernel/pci-sysfs.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -26,7 +26,7 @@ static int hose_mmap_page_range(struct pci_controller *hose,
		base = sparse ? hose->sparse_io_base : hose->dense_io_base;

		vma->vm_pgoff += base >> PAGE_SHIFT;
		vma->vm_flags \|= (VM_IO \| VM_RESERVED);
		vma->vm_flags \|= VM_IO \| VM_DONTEXPAND \| VM_DONTDUMP;

		return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
		vma->vm_end - vma->vm_start,

arch/ia64/kernel/perfmon.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -2307,7 +2307,7 @@ pfm_smpl_buffer_alloc(struct task_struct task, struct file filp, pfm_context_t
		*/
		vma->vm_mm = mm;
		vma->vm_file = get_file(filp);
		vma->vm_flags = VM_READ\| VM_MAYREAD \|VM_RESERVED;
		vma->vm_flags = VM_READ\|VM_MAYREAD\|VM_DONTEXPAND\|VM_DONTDUMP;
		vma->vm_page_prot = PAGE_READONLY; /* XXX may need to change */

		/*

arch/ia64/mm/init.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -138,7 +138,8 @@ ia64_init_addr_space (void)
		vma->vm_mm = current->mm;
		vma->vm_end = PAGE_SIZE;
		vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) \| _PAGE_MA_NAT);
		vma->vm_flags = VM_READ \| VM_MAYREAD \| VM_IO \| VM_RESERVED;
		vma->vm_flags = VM_READ \| VM_MAYREAD \| VM_IO \|
		VM_DONTEXPAND \| VM_DONTDUMP;
		down_write(&current->mm->mmap_sem);
		if (insert_vm_struct(current->mm, vma)) {
		up_write(&current->mm->mmap_sem);

arch/powerpc/kvm/book3s_hv.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1183,7 +1183,7 @@ static const struct vm_operations_struct kvm_rma_vm_ops = {

		static int kvm_rma_mmap(struct file file, struct vm_area_struct vma)
		{
		vma->vm_flags \|= VM_RESERVED;
		vma->vm_flags \|= VM_DONTEXPAND \| VM_DONTDUMP;
		vma->vm_ops = &kvm_rma_vm_ops;
		return 0;
		}

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