Rather than having separate logic for each case determining whether to zap
the deposited table, simply track this via a boolean.
We check separately if the architecture requires it.
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
---
mm/huge_memory.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 499c31bf8f83..c4e00c645e58 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2431,6 +2431,7 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
pmd_t *pmd, unsigned long addr)
{
struct folio *folio = NULL;
+ bool needs_deposit = false;
bool flush_needed = false;
spinlock_t *ptl;
pmd_t orig_pmd;
@@ -2450,23 +2451,18 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
tlb->fullmm);
arch_check_zapped_pmd(vma, orig_pmd);
tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
- if (vma_is_special_huge(vma)) {
- if (arch_needs_pgtable_deposit())
- zap_deposited_table(tlb->mm, pmd);
+ if (vma_is_special_huge(vma))
goto out;
- }
if (is_huge_zero_pmd(orig_pmd)) {
- if (!vma_is_dax(vma) || arch_needs_pgtable_deposit())
- zap_deposited_table(tlb->mm, pmd);
+ needs_deposit = !vma_is_dax(vma);
goto out;
}
if (pmd_present(orig_pmd)) {
- struct page *page = pmd_page(orig_pmd);
+ folio = pmd_folio(orig_pmd);
flush_needed = true;
- folio = page_folio(page);
- folio_remove_rmap_pmd(folio, page, vma);
+ folio_remove_rmap_pmd(folio, &folio->page, vma);
WARN_ON_ONCE(folio_mapcount(folio) < 0);
} else if (pmd_is_valid_softleaf(orig_pmd)) {
const softleaf_t entry = softleaf_from_pmd(orig_pmd);
@@ -2481,11 +2477,9 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
}
if (folio_test_anon(folio)) {
- zap_deposited_table(tlb->mm, pmd);
+ needs_deposit = true;
add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
} else {
- if (arch_needs_pgtable_deposit())
- zap_deposited_table(tlb->mm, pmd);
add_mm_counter(tlb->mm, mm_counter_file(folio),
-HPAGE_PMD_NR);
@@ -2505,6 +2499,9 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
}
out:
+ if (arch_needs_pgtable_deposit() || needs_deposit)
+ zap_deposited_table(tlb->mm, pmd);
+
spin_unlock(ptl);
if (flush_needed)
tlb_remove_page_size(tlb, &folio->page, HPAGE_PMD_SIZE);
--
2.53.0
On Thu, Mar 19, 2026 at 01:00:13PM +0000, Lorenzo Stoakes (Oracle) wrote:
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 499c31bf8f83..c4e00c645e58 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -2431,6 +2431,7 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
> pmd_t *pmd, unsigned long addr)
> {
> struct folio *folio = NULL;
> + bool needs_deposit = false;
I think 'has_deposit' is a better name here.
And initialize it to arch_needs_pgtable_deposit().
--
Kiryl Shutsemau / Kirill A. Shutemov
On Thu, Mar 19, 2026 at 05:03:10PM +0000, Kiryl Shutsemau wrote:
> On Thu, Mar 19, 2026 at 01:00:13PM +0000, Lorenzo Stoakes (Oracle) wrote:
> > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > index 499c31bf8f83..c4e00c645e58 100644
> > --- a/mm/huge_memory.c
> > +++ b/mm/huge_memory.c
> > @@ -2431,6 +2431,7 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
> > pmd_t *pmd, unsigned long addr)
> > {
> > struct folio *folio = NULL;
> > + bool needs_deposit = false;
>
> I think 'has_deposit' is a better name here.
That's fine, can rename.
>
> And initialize it to arch_needs_pgtable_deposit().
Yeah I considered that, but then you have to do logic like:
has_deposit = has_deposit || <whatever>;
Which is a bit ugly.
Could do
has_deposit |= <whatever>
But then that's weird with bools.
Could be has_non_arch_deposit but that's too long and... yeah :>)
>
> --
> Kiryl Shutsemau / Kirill A. Shutemov
Cheers, Lorenzo
On Thu, Mar 19, 2026 at 05:18:11PM +0000, Lorenzo Stoakes (Oracle) wrote:
> On Thu, Mar 19, 2026 at 05:03:10PM +0000, Kiryl Shutsemau wrote:
> > On Thu, Mar 19, 2026 at 01:00:13PM +0000, Lorenzo Stoakes (Oracle) wrote:
> > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > > index 499c31bf8f83..c4e00c645e58 100644
> > > --- a/mm/huge_memory.c
> > > +++ b/mm/huge_memory.c
> > > @@ -2431,6 +2431,7 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
> > > pmd_t *pmd, unsigned long addr)
> > > {
> > > struct folio *folio = NULL;
> > > + bool needs_deposit = false;
> >
> > I think 'has_deposit' is a better name here.
>
> That's fine, can rename.
>
> >
> > And initialize it to arch_needs_pgtable_deposit().
>
> Yeah I considered that, but then you have to do logic like:
>
> has_deposit = has_deposit || <whatever>;
>
> Which is a bit ugly.
You are overthinking it. Just do
if (!vma_is_dax(vma))
has_deposit = true;
No need in squeezing it into single line.
--
Kiryl Shutsemau / Kirill A. Shutemov
On Thu, Mar 19, 2026 at 09:56:53PM +0000, Kiryl Shutsemau wrote:
> On Thu, Mar 19, 2026 at 05:18:11PM +0000, Lorenzo Stoakes (Oracle) wrote:
> > On Thu, Mar 19, 2026 at 05:03:10PM +0000, Kiryl Shutsemau wrote:
> > > On Thu, Mar 19, 2026 at 01:00:13PM +0000, Lorenzo Stoakes (Oracle) wrote:
> > > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > > > index 499c31bf8f83..c4e00c645e58 100644
> > > > --- a/mm/huge_memory.c
> > > > +++ b/mm/huge_memory.c
> > > > @@ -2431,6 +2431,7 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
> > > > pmd_t *pmd, unsigned long addr)
> > > > {
> > > > struct folio *folio = NULL;
> > > > + bool needs_deposit = false;
> > >
> > > I think 'has_deposit' is a better name here.
> >
> > That's fine, can rename.
> >
> > >
> > > And initialize it to arch_needs_pgtable_deposit().
> >
> > Yeah I considered that, but then you have to do logic like:
> >
> > has_deposit = has_deposit || <whatever>;
> >
> > Which is a bit ugly.
>
> You are overthinking it. Just do
Well I would argue you're overthinking the review comments here ;)
>
> if (!vma_is_dax(vma))
> has_deposit = true;
>
> No need in squeezing it into single line.
Well part of the point here was to avoid ugly:
Indent
Indent
Indent
And that worsens the situation.
Let me think about this again on respin.
>
> --
> Kiryl Shutsemau / Kirill A. Shutemov
Thanks, Lorenzo
On Fri, Mar 20, 2026 at 02:00:04PM +0000, Lorenzo Stoakes (Oracle) wrote: > On Thu, Mar 19, 2026 at 09:56:53PM +0000, Kiryl Shutsemau wrote: > > > > if (!vma_is_dax(vma)) > > has_deposit = true; > > > > No need in squeezing it into single line. > > Well part of the point here was to avoid ugly: > > Indent > Indent > Indent Actually it's not too bad let's do that. Cheers, Lorenzo
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