Commit e9cdd6e7 authored Oct 16, 2013 by Cyrill Gorcunov Committed by Linus Torvalds Oct 16, 2013

mm: /proc/pid/pagemap: inspect _PAGE_SOFT_DIRTY only on present pages



If a page we are inspecting is in swap we may occasionally report it as
having soft dirty bit (even if it is clean).  The pte_soft_dirty helper
should be called on present pte only.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent c3d16e16

fs/proc/task_mmu.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -941,6 +941,8 @@ static void pte_to_pagemap_entry(pagemap_entry_t pme, struct pagemapread pm,
		frame = pte_pfn(pte);
		flags = PM_PRESENT;
		page = vm_normal_page(vma, addr, pte);
		if (pte_soft_dirty(pte))
		flags2 \|= __PM_SOFT_DIRTY;
		} else if (is_swap_pte(pte)) {
		swp_entry_t entry;
		if (pte_swp_soft_dirty(pte))
		@@ -960,7 +962,7 @@ static void pte_to_pagemap_entry(pagemap_entry_t pme, struct pagemapread pm,

		if (page && !PageAnon(page))
		flags \|= PM_FILE;
		if ((vma->vm_flags & VM_SOFTDIRTY) \|\| pte_soft_dirty(pte))
		if ((vma->vm_flags & VM_SOFTDIRTY))
		flags2 \|= __PM_SOFT_DIRTY;

		*pme = make_pme(PM_PFRAME(frame) \| PM_STATUS2(pm->v2, flags2) \| flags);

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