korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-11 04:18:39 +08:00
Code Issues Packages Projects Releases Wiki Activity

mm: introduce arch_do_swap_page_nr() which allows restore metadata for nr pages

Browse Source 
Should do_swap_page() have the capability to directly map a large folio,
metadata restoration becomes necessary for a specified number of pages
denoted as nr.  It's important to highlight that metadata restoration is
solely required by the SPARC platform, which, however, does not enable
THP_SWAP.  Consequently, in the present kernel configuration, there exists
no practical scenario where users necessitate the restoration of nr
metadata.  Platforms implementing THP_SWAP might invoke this function with
nr values exceeding 1, subsequent to do_swap_page() successfully mapping
an entire large folio.  Nonetheless, their arch_do_swap_page_nr()
functions remain empty.

Link: https://lkml.kernel.org/r/20240529082824.150954-5-21cnbao@gmail.com
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chuanhua Han <hanchuanhua@oppo.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Gao Xiang <xiang@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Barry Song 2024-05-29 20:28:22 +12:00 committed by Andrew Morton
parent 3f9abcaa3e
commit 29f252cdc2
2 changed files with 21 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
include/linux/pgtable.h
View File

@ -1089,6 +1089,15 @@ static inline int pgd_same(pgd_t pgd_a, pgd_t pgd_b)
})
#ifndef __HAVE_ARCH_DO_SWAP_PAGE
static inline void arch_do_swap_page_nr(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long addr,
pte_t pte, pte_t oldpte,
int nr)
{
}
#else
/*
* Some architectures support metadata associated with a page. When a
* page is being swapped out, this metadata must be saved so it can be
@ -1097,12 +1106,17 @@ static inline int pgd_same(pgd_t pgd_a, pgd_t pgd_b)
* page as metadata for the page. arch_do_swap_page() can restore this
* metadata when a page is swapped back in.
*/
static inline void arch_do_swap_page(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long addr,
pte_t pte, pte_t oldpte)
static inline void arch_do_swap_page_nr(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long addr,
pte_t pte, pte_t oldpte,
int nr)
{
for (int i = 0; i < nr; i++) {
arch_do_swap_page(vma->vm_mm, vma, addr + i * PAGE_SIZE,
pte_advance_pfn(pte, i),
pte_advance_pfn(oldpte, i));
}
}
#endif

3
mm/memory.c
View File

@ -4308,7 +4308,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
VM_BUG_ON(!folio_test_anon(folio) ||
(pte_write(pte) && !PageAnonExclusive(page)));
set_pte_at(vma->vm_mm, vmf->address, vmf->pte, pte);
arch_do_swap_page(vma->vm_mm, vma, vmf->address, pte, vmf->orig_pte);
arch_do_swap_page_nr(vma->vm_mm, vma, vmf->address,
pte, vmf->orig_pte, 1);
folio_unlock(folio);
if (folio != swapcache && swapcache) {