From 861f2fb8e796022b4928cab9c74fca6681a1c557 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 29 Oct 2005 18:16:17 -0700 Subject: [PATCH] [PATCH] mm: zap_pte out of line There used to be just one call to zap_pte, but it shouldn't be inline now there are two. Check for the common case pte_none before calling, and move its rss accounting up into install_page or install_file_pte - which helps the next patch. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/fremap.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/mm/fremap.c b/mm/fremap.c index 224cc1598b3..7f08d10ceaf 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -20,34 +20,32 @@ #include #include -static inline void zap_pte(struct mm_struct *mm, struct vm_area_struct *vma, +static int zap_pte(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { pte_t pte = *ptep; + struct page *page = NULL; - if (pte_none(pte)) - return; if (pte_present(pte)) { unsigned long pfn = pte_pfn(pte); - struct page *page; - flush_cache_page(vma, addr, pfn); pte = ptep_clear_flush(vma, addr, ptep); if (unlikely(!pfn_valid(pfn))) { print_bad_pte(vma, pte, addr); - return; + goto out; } page = pfn_to_page(pfn); if (pte_dirty(pte)) set_page_dirty(page); page_remove_rmap(page); page_cache_release(page); - dec_mm_counter(mm, file_rss); } else { if (!pte_file(pte)) free_swap_and_cache(pte_to_swp_entry(pte)); pte_clear(mm, addr, ptep); } +out: + return !!page; } /* @@ -96,9 +94,9 @@ int install_page(struct mm_struct *mm, struct vm_area_struct *vma, if (page_mapcount(page) > INT_MAX/2) goto err_unlock; - zap_pte(mm, vma, addr, pte); + if (pte_none(*pte) || !zap_pte(mm, vma, addr, pte)) + inc_mm_counter(mm, file_rss); - inc_mm_counter(mm, file_rss); flush_icache_page(vma, page); set_pte_at(mm, addr, pte, mk_pte(page, prot)); page_add_file_rmap(page); @@ -145,7 +143,8 @@ int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, if (!pte) goto err_unlock; - zap_pte(mm, vma, addr, pte); + if (!pte_none(*pte) && zap_pte(mm, vma, addr, pte)) + dec_mm_counter(mm, file_rss); set_pte_at(mm, addr, pte, pgoff_to_pte(pgoff)); pte_val = *pte; -- 2.20.1