Message ID | 88e67645-f467-c279-bf5e-af4b5c6b13eb@google.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | mm: page_vma_mapped_walk() cleanup and THP fixes | expand |
Thanks for this, I've read through page_vma_mapped_walk() a few too many times recently and it annoyed me enough to start writing some patches to clean it up, but happy to see this instead. I confirmed pvmw->page isn't modified here or in map/check_pte(pvmw), so the patch looks good to me: Reviewed-by: Alistair Popple <apopple@nvidia.com> On Thursday, 10 June 2021 4:34:40 PM AEST Hugh Dickins wrote: > page_vma_mapped_walk() cleanup: sometimes the local copy of pvwm->page was > used, sometimes pvmw->page itself: use the local copy "page" throughout. > > Signed-off-by: Hugh Dickins <hughd@google.com> > Cc: <stable@vger.kernel.org> > --- > mm/page_vma_mapped.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c > index e37bd43904af..a6dbf714ca15 100644 > --- a/mm/page_vma_mapped.c > +++ b/mm/page_vma_mapped.c > @@ -156,7 +156,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > if (pvmw->pte) > goto next_pte; > > - if (unlikely(PageHuge(pvmw->page))) { > + if (unlikely(PageHuge(page))) { > /* when pud is not present, pte will be NULL */ > pvmw->pte = huge_pte_offset(mm, pvmw->address, page_size(page)); > if (!pvmw->pte) > @@ -217,8 +217,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > * cannot return prematurely, while zap_huge_pmd() has > * cleared *pmd but not decremented compound_mapcount(). > */ > - if ((pvmw->flags & PVMW_SYNC) && > - PageTransCompound(pvmw->page)) { > + if ((pvmw->flags & PVMW_SYNC) && PageTransCompound(page)) { > spinlock_t *ptl = pmd_lock(mm, pvmw->pmd); > > spin_unlock(ptl); > @@ -234,9 +233,9 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > return true; > next_pte: > /* Seek to next pte only makes sense for THP */ > - if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page)) > + if (!PageTransHuge(page) || PageHuge(page)) > return not_found(pvmw); > - end = vma_address_end(pvmw->page, pvmw->vma); > + end = vma_address_end(page, pvmw->vma); > do { > pvmw->address += PAGE_SIZE; > if (pvmw->address >= end) > -- > 2.26.2 >
On Wed, Jun 09, 2021 at 11:34:40PM -0700, Hugh Dickins wrote: > page_vma_mapped_walk() cleanup: sometimes the local copy of pvwm->page was > used, sometimes pvmw->page itself: use the local copy "page" throughout. > > Signed-off-by: Hugh Dickins <hughd@google.com> > Cc: <stable@vger.kernel.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> A question below. > --- > mm/page_vma_mapped.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c > index e37bd43904af..a6dbf714ca15 100644 > --- a/mm/page_vma_mapped.c > +++ b/mm/page_vma_mapped.c > @@ -156,7 +156,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > if (pvmw->pte) > goto next_pte; > > - if (unlikely(PageHuge(pvmw->page))) { > + if (unlikely(PageHuge(page))) { > /* when pud is not present, pte will be NULL */ > pvmw->pte = huge_pte_offset(mm, pvmw->address, page_size(page)); > if (!pvmw->pte) > @@ -217,8 +217,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > * cannot return prematurely, while zap_huge_pmd() has > * cleared *pmd but not decremented compound_mapcount(). > */ > - if ((pvmw->flags & PVMW_SYNC) && > - PageTransCompound(pvmw->page)) { > + if ((pvmw->flags & PVMW_SYNC) && PageTransCompound(page)) { > spinlock_t *ptl = pmd_lock(mm, pvmw->pmd); > > spin_unlock(ptl); > @@ -234,9 +233,9 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > return true; > next_pte: > /* Seek to next pte only makes sense for THP */ > - if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page)) > + if (!PageTransHuge(page) || PageHuge(page)) > return not_found(pvmw); > - end = vma_address_end(pvmw->page, pvmw->vma); > + end = vma_address_end(page, pvmw->vma); > do { > pvmw->address += PAGE_SIZE; > if (pvmw->address >= end) I see two more pvmw->page in this loop. Do you leave them here as the code will be rewritten later in the patchset?
On Thu, Jun 10, 2021 at 11:55:22AM +0300, Kirill A. Shutemov wrote: > > @@ -234,9 +233,9 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) > > return true; > > next_pte: > > /* Seek to next pte only makes sense for THP */ > > - if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page)) > > + if (!PageTransHuge(page) || PageHuge(page)) > > return not_found(pvmw); > > - end = vma_address_end(pvmw->page, pvmw->vma); > > + end = vma_address_end(page, pvmw->vma); > > do { > > pvmw->address += PAGE_SIZE; > > if (pvmw->address >= end) > > I see two more pvmw->page in this loop. Do you leave them here as the code > will be rewritten later in the patchset? I think they've got removed in previous series ("[PATCH v2 04/10] mm/thp: fix vma_address() if virtual address below file offset"). Reviewed-by: Peter Xu <peterx@redhat.com>
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index e37bd43904af..a6dbf714ca15 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -156,7 +156,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) if (pvmw->pte) goto next_pte; - if (unlikely(PageHuge(pvmw->page))) { + if (unlikely(PageHuge(page))) { /* when pud is not present, pte will be NULL */ pvmw->pte = huge_pte_offset(mm, pvmw->address, page_size(page)); if (!pvmw->pte) @@ -217,8 +217,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) * cannot return prematurely, while zap_huge_pmd() has * cleared *pmd but not decremented compound_mapcount(). */ - if ((pvmw->flags & PVMW_SYNC) && - PageTransCompound(pvmw->page)) { + if ((pvmw->flags & PVMW_SYNC) && PageTransCompound(page)) { spinlock_t *ptl = pmd_lock(mm, pvmw->pmd); spin_unlock(ptl); @@ -234,9 +233,9 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return true; next_pte: /* Seek to next pte only makes sense for THP */ - if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page)) + if (!PageTransHuge(page) || PageHuge(page)) return not_found(pvmw); - end = vma_address_end(pvmw->page, pvmw->vma); + end = vma_address_end(page, pvmw->vma); do { pvmw->address += PAGE_SIZE; if (pvmw->address >= end)
page_vma_mapped_walk() cleanup: sometimes the local copy of pvwm->page was used, sometimes pvmw->page itself: use the local copy "page" throughout. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> --- mm/page_vma_mapped.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)