diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2022-09-02 20:46:32 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-10-03 14:02:51 -0700 |
| commit | f102cd8b173e066179b472fb6e3b18e31a1cc394 (patch) | |
| tree | b911c3fcb713a228fe08c8e830b3246b15ea79e9 /mm | |
| parent | 2c3f6194b008b23e52a8e135bdd56b67fdaa55ca (diff) | |
swapfile: convert unuse_pte_range() to use a folio
Delay fetching the precise page from the folio until we're in unuse_pte().
Saves many calls to compound_head().
Link: https://lkml.kernel.org/r/20220902194653.1739778-37-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/swapfile.c | 33 |
1 files changed, 19 insertions, 14 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index e3e1bd3d20b1..3820b5ab64d9 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1758,8 +1758,9 @@ static inline int pte_same_as_swp(pte_t pte, pte_t swp_pte) * force COW, vm_page_prot omits write permission from any private vma. */ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, swp_entry_t entry, struct page *page) + unsigned long addr, swp_entry_t entry, struct folio *folio) { + struct page *page = folio_file_page(folio, swp_offset(entry)); struct page *swapcache; spinlock_t *ptl; pte_t *pte, new_pte; @@ -1831,17 +1832,18 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end, unsigned int type) { - struct page *page; swp_entry_t entry; pte_t *pte; struct swap_info_struct *si; - unsigned long offset; int ret = 0; volatile unsigned char *swap_map; si = swap_info[type]; pte = pte_offset_map(pmd, addr); do { + struct folio *folio; + unsigned long offset; + if (!is_swap_pte(*pte)) continue; @@ -1852,8 +1854,9 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, offset = swp_offset(entry); pte_unmap(pte); swap_map = &si->swap_map[offset]; - page = lookup_swap_cache(entry, vma, addr); - if (!page) { + folio = swap_cache_get_folio(entry, vma, addr); + if (!folio) { + struct page *page; struct vm_fault vmf = { .vma = vma, .address = addr, @@ -1863,25 +1866,27 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE, &vmf); + if (page) + folio = page_folio(page); } - if (!page) { + if (!folio) { if (*swap_map == 0 || *swap_map == SWAP_MAP_BAD) goto try_next; return -ENOMEM; } - lock_page(page); - wait_on_page_writeback(page); - ret = unuse_pte(vma, pmd, addr, entry, page); + folio_lock(folio); + folio_wait_writeback(folio); + ret = unuse_pte(vma, pmd, addr, entry, folio); if (ret < 0) { - unlock_page(page); - put_page(page); + folio_unlock(folio); + folio_put(folio); goto out; } - try_to_free_swap(page); - unlock_page(page); - put_page(page); + folio_free_swap(folio); + folio_unlock(folio); + folio_put(folio); try_next: pte = pte_offset_map(pmd, addr); } while (pte++, addr += PAGE_SIZE, addr != end); |