github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-27 08:33:17 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

mm/memory: pass folio and pte to restore_exclusive_pte()

Browse Source 
Let's pass the folio and the pte to restore_exclusive_pte(), so we can
avoid repeated page_folio() and ptep_get().  To do that, pass the pte to
try_restore_exclusive_pte() and use a folio in there already.

While at it, just avoid the "swp_entry_t entry" variable in
try_restore_exclusive_pte() and add a folio-locked check to
restore_exclusive_pte().

Link: https://lkml.kernel.org/r/20250226132257.2826043-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
David Hildenbrand 2025-02-26 14:22:55 +01:00 committed by Andrew Morton
parent db0f6e674c
commit 248624f9c6
1 changed files with 14 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
mm/memory.c
View File

@ -717,14 +717,13 @@ struct folio *vm_normal_folio_pmd(struct vm_area_struct *vma,
#endif
static void restore_exclusive_pte(struct vm_area_struct *vma,
struct page *page, unsigned long address,
pte_t *ptep)
struct folio *folio, struct page *page, unsigned long address,
pte_t *ptep, pte_t orig_pte)
{
struct folio *folio = page_folio(page);
pte_t orig_pte;
pte_t pte;
orig_pte = ptep_get(ptep);
VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio);
pte = pte_mkold(mk_pte(page, READ_ONCE(vma->vm_page_prot)));
if (pte_swp_soft_dirty(orig_pte))
pte = pte_mksoft_dirty(pte);
@ -751,16 +750,15 @@ static void restore_exclusive_pte(struct vm_area_struct *vma,
* Tries to restore an exclusive pte if the page lock can be acquired without
* sleeping.
*/
static int
try_restore_exclusive_pte(pte_t *src_pte, struct vm_area_struct *vma,
unsigned long addr)
static int try_restore_exclusive_pte(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep, pte_t orig_pte)
{
swp_entry_t entry = pte_to_swp_entry(ptep_get(src_pte));
struct page *page = pfn_swap_entry_to_page(entry);
struct page *page = pfn_swap_entry_to_page(pte_to_swp_entry(orig_pte));
struct folio *folio = page_folio(page);
if (trylock_page(page)) {
restore_exclusive_pte(vma, page, addr, src_pte);
unlock_page(page);
if (folio_trylock(folio)) {
restore_exclusive_pte(vma, folio, page, addr, ptep, orig_pte);
folio_unlock(folio);
return 0;
}
@ -866,7 +864,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
* (ie. COW) mappings.
*/
VM_BUG_ON(!is_cow_mapping(src_vma->vm_flags));
if (try_restore_exclusive_pte(src_pte, src_vma, addr))
if (try_restore_exclusive_pte(src_vma, addr, src_pte, orig_pte))
return -EBUSY;
return -ENOENT;
} else if (is_pte_marker_entry(entry)) {
@ -3987,7 +3985,8 @@ static vm_fault_t remove_device_exclusive_entry(struct vm_fault *vmf)
vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address,
&vmf->ptl);
if (likely(vmf->pte && pte_same(ptep_get(vmf->pte), vmf->orig_pte)))
restore_exclusive_pte(vma, vmf->page, vmf->address, vmf->pte);
restore_exclusive_pte(vma, folio, vmf->page, vmf->address,
vmf->pte, vmf->orig_pte);
if (vmf->pte)
pte_unmap_unlock(vmf->pte, vmf->ptl);