| Message ID | 20220504003958.18402-1-richard.weiyang@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] mm/mlock: not handle NULL vma specially | expand |
On Wed, 4 May 2022 00:39:57 +0000 Wei Yang <richard.weiyang@gmail.com> wrote: > If we can't find a proper vma, the loop would terminate as expected. > > It's not necessary to handle it specially. > > ... > > --- a/mm/mlock.c > +++ b/mm/mlock.c > @@ -504,11 +504,7 @@ static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm, > if (mm == NULL) > mm = current->mm; > > - vma = find_vma(mm, start); > - if (vma == NULL) > - return 0; > - > - for (; vma ; vma = vma->vm_next) { > + for (vma = find_vma(mm, start); vma ; vma = vma->vm_next) { > if (start >= vma->vm_end) > continue; > if (start + len <= vma->vm_start) The mapletree patches mangle this code a lot. Please take a look at linux-next or the mm-unstabe branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm early to mid next week, see if you see anything which should be addressed.
On Sun, May 8, 2022 at 5:03 AM Andrew Morton <akpm@linux-foundation.org> wrote: > > On Wed, 4 May 2022 00:39:57 +0000 Wei Yang <richard.weiyang@gmail.com> wrote: > > > If we can't find a proper vma, the loop would terminate as expected. > > > > It's not necessary to handle it specially. > > > > ... > > > > --- a/mm/mlock.c > > +++ b/mm/mlock.c > > @@ -504,11 +504,7 @@ static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm, > > if (mm == NULL) > > mm = current->mm; > > > > - vma = find_vma(mm, start); > > - if (vma == NULL) > > - return 0; > > - > > - for (; vma ; vma = vma->vm_next) { > > + for (vma = find_vma(mm, start); vma ; vma = vma->vm_next) { > > if (start >= vma->vm_end) > > continue; > > if (start + len <= vma->vm_start) > > The mapletree patches mangle this code a lot. > > Please take a look at linux-next or the mm-unstabe branch at > git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm early to mid next > week, see if you see anything which should be addressed. > I took a look at mm-unstabe branch with last commit 2b58b3f33ba2 mm/shmem: convert shmem_swapin_page() to shmem_swapin_folio() Function count_mm_mlocked_page_nr() looks not changed. Do I need to rebase on top of it?
On Sun, 8 May 2022 05:56:15 +0800 Wei Yang <richard.weiyang@gmail.com> wrote: > > > - vma = find_vma(mm, start); > > > - if (vma == NULL) > > > - return 0; > > > - > > > - for (; vma ; vma = vma->vm_next) { > > > + for (vma = find_vma(mm, start); vma ; vma = vma->vm_next) { > > > if (start >= vma->vm_end) > > > continue; > > > if (start + len <= vma->vm_start) > > > > The mapletree patches mangle this code a lot. > > > > Please take a look at linux-next or the mm-unstabe branch at > > git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm early to mid next > > week, see if you see anything which should be addressed. > > > > I took a look at mm-unstabe branch with last commit > > 2b58b3f33ba2 mm/shmem: convert shmem_swapin_page() to shmem_swapin_folio() > It isn't early to mid next week yet ;) > Function count_mm_mlocked_page_nr() looks not changed. > > Do I need to rebase on top of it? static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm, unsigned long start, size_t len) { struct vm_area_struct *vma; unsigned long count = 0; unsigned long end; VMA_ITERATOR(vmi, mm, start); if (mm == NULL) mm = current->mm; /* Don't overflow past ULONG_MAX */ if (unlikely(ULONG_MAX - len < start)) end = ULONG_MAX; else end = start + len; for_each_vma_range(vmi, vma, end) { if (vma->vm_flags & VM_LOCKED) { if (start > vma->vm_start) count -= (start - vma->vm_start); if (end < vma->vm_end) { count += end - vma->vm_start; break; } count += vma->vm_end - vma->vm_start; } } return count >> PAGE_SHIFT; }
diff --git a/mm/mlock.c b/mm/mlock.c index efd2dd2943de..0b7cf7d60922 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -504,11 +504,7 @@ static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm, if (mm == NULL) mm = current->mm; - vma = find_vma(mm, start); - if (vma == NULL) - return 0; - - for (; vma ; vma = vma->vm_next) { + for (vma = find_vma(mm, start); vma ; vma = vma->vm_next) { if (start >= vma->vm_end) continue; if (start + len <= vma->vm_start)
If we can't find a proper vma, the loop would terminate as expected. It's not necessary to handle it specially. Signed-off-by: Wei Yang <richard.weiyang@gmail.com> --- mm/mlock.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)