| Message ID | 20210916215839.95177-1-peterx@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/smaps: Use vma->vm_pgoff directly when counting partial swap | expand |
On 9/16/21 11:58 PM, Peter Xu wrote: > linear_page_index(vma, vma->vm_start) of a shmem vma is exactly vm_pgoff. Could you use "vma->vm_pgoff + vma_pages(vma)" instead of the other linear_page_index() then? But now I wonder, is smaps_pte_hole() broken? it calls shmem_partial_swap_usage with addresses, not pgoffs? > Cc: Vlastimil Babka <vbabka@suse.cz> > Cc: Hugh Dickins <hughd@google.com> > Signed-off-by: Peter Xu <peterx@redhat.com> > --- > mm/shmem.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/mm/shmem.c b/mm/shmem.c > index 96ccf6e941aa..2aef5b8e17c9 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -856,8 +856,7 @@ unsigned long shmem_swap_usage(struct vm_area_struct *vma) > return swapped << PAGE_SHIFT; > > /* Here comes the more involved part */ > - return shmem_partial_swap_usage(mapping, > - linear_page_index(vma, vma->vm_start), > + return shmem_partial_swap_usage(mapping, vma->vm_pgoff, > linear_page_index(vma, vma->vm_end)); > } > >
On Fri, Sep 17, 2021 at 12:17:32AM +0200, Vlastimil Babka wrote: > On 9/16/21 11:58 PM, Peter Xu wrote: > > linear_page_index(vma, vma->vm_start) of a shmem vma is exactly vm_pgoff. > > Could you use "vma->vm_pgoff + vma_pages(vma)" instead of the other > linear_page_index() then? Sure. > > But now I wonder, is smaps_pte_hole() broken? it calls > shmem_partial_swap_usage with addresses, not pgoffs? Hmm, that seems true.. I guess it still gets the right number when start==0 and when the vma covers the whole file (which could be the simplest scenario), but not otherwise. I'll add a new patch. Thanks,
diff --git a/mm/shmem.c b/mm/shmem.c index 96ccf6e941aa..2aef5b8e17c9 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -856,8 +856,7 @@ unsigned long shmem_swap_usage(struct vm_area_struct *vma) return swapped << PAGE_SHIFT; /* Here comes the more involved part */ - return shmem_partial_swap_usage(mapping, - linear_page_index(vma, vma->vm_start), + return shmem_partial_swap_usage(mapping, vma->vm_pgoff, linear_page_index(vma, vma->vm_end)); }
linear_page_index(vma, vma->vm_start) of a shmem vma is exactly vm_pgoff. Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Peter Xu <peterx@redhat.com> --- mm/shmem.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)