Re: [PATCH v3 04/13] smaps: remove mem_size_stats->vma and use walk_page_vma()

Naoya Horiguchi
2014-06-26T14:42:34Z

Hi Jerome,

On Thu, Jun 26, 2014 at 03:35:36PM +0200, Jerome Marchand wrote:
> On 06/20/2014 10:11 PM, Naoya Horiguchi wrote:
> > pagewalk.c can handle vma in itself, so we don't have to pass vma via
> > walk->private. And show_smap() walks pages on vma basis, so using
> > walk_page_vma() is preferable.
> >
> > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
> > ---
> > fs/proc/task_mmu.c | 10 ++++------
> > 1 file changed, 4 insertions(+), 6 deletions(-)
> >
> > diff --git v3.16-rc1.orig/fs/proc/task_mmu.c v3.16-rc1/fs/proc/task_mmu.c
> > index cfa63ee92c96..9b6c7d4fd3f4 100644
> > --- v3.16-rc1.orig/fs/proc/task_mmu.c
> > +++ v3.16-rc1/fs/proc/task_mmu.c
> > @@ -430,7 +430,6 @@ const struct file_operations proc_tid_maps_operations = {
> >
> > #ifdef CONFIG_PROC_PAGE_MONITOR
> > struct mem_size_stats {
> > - struct vm_area_struct *vma;
> > unsigned long resident;
> > unsigned long shared_clean;
> > unsigned long shared_dirty;
> > @@ -449,7 +448,7 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr,
> > unsigned long ptent_size, struct mm_walk *walk)
> > {
> > struct mem_size_stats *mss = walk->private;
> > - struct vm_area_struct *vma = mss->vma;
> > + struct vm_area_struct *vma = walk->vma;
> > pgoff_t pgoff = linear_page_index(vma, addr);
> > struct page *page = NULL;
> > int mapcount;
> > @@ -501,7 +500,7 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
> > struct mm_walk *walk)
> > {
> > struct mem_size_stats *mss = walk->private;
> > - struct vm_area_struct *vma = mss->vma;
> > + struct vm_area_struct *vma = walk->vma;
> > pte_t *pte;
> > spinlock_t *ptl;
> >
> > @@ -590,14 +589,13 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
> > struct mm_walk smaps_walk = {
> > .pmd_entry = smaps_pte_range,
> > .mm = vma->vm_mm,
> > + .vma = vma,
>
> Seems redundant: walk_page_vma() sets walk.vma anyway and so does
> walk_page_range(). Is there any case when the caller should set .vma itself?

Correct, no need to set in caller side, thank you.

Naoya Horiguchi