[patch -mm] smaps: flush tlb only once for each vma

[patch -mm] smaps: flush tlb only once for each vma

[David Rientjes]

Flush the entire user address space from the TLB for each VMA in the 
task_struct list when clearing reference bits with /proc/pid/clear_refs.  
It's more efficient than flushing each page individually depending on 
pte_young().

Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: David Rientjes <rientjes@google.com>
---
 fs/proc/task_mmu.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -276,7 +276,6 @@ static void clear_refs_one_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 		if (pte_young(ptent)) {
 			ptent = pte_mkold(ptent);
 			set_pte_at(vma->vm_mm, addr, pte, ptent);
-			flush_tlb_page(vma, addr);
 		}
 		ClearPageReferenced(page);
 	}
@@ -358,6 +357,7 @@ void clear_refs_smap(struct mm_struct *mm)
 	for (vma = mm->mmap; vma; vma = vma->vm_next)
 		if (vma->vm_mm && !is_vm_hugetlb_page(vma))
 			for_each_pmd(vma, clear_refs_one_pmd, NULL);
+	flush_tlb_mm(mm);
 	up_read(&mm->mmap_sem);
 }