diff options
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | mm/huge_memory.c | 4 | ||||
| -rw-r--r-- | mm/memory.c | 42 |
3 files changed, 41 insertions, 7 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index eb5e4bc946cc..0acea73af839 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2508,7 +2508,7 @@ enum mf_action_page_type { #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS) extern void clear_huge_page(struct page *page, - unsigned long addr, + unsigned long addr_hint, unsigned int pages_per_huge_page); extern void copy_user_huge_page(struct page *dst, struct page *src, unsigned long addr, struct vm_area_struct *vma, diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 772048c233d1..0b51e70e0a8b 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -567,7 +567,7 @@ static int __do_huge_pmd_anonymous_page(struct vm_fault *vmf, struct page *page, goto release; } - clear_huge_page(page, haddr, HPAGE_PMD_NR); + clear_huge_page(page, vmf->address, HPAGE_PMD_NR); /* * The memory barrier inside __SetPageUptodate makes sure that * clear_huge_page writes become visible before the set_pmd_at() @@ -1305,7 +1305,7 @@ alloc: count_vm_event(THP_FAULT_ALLOC); if (!page) - clear_huge_page(new_page, haddr, HPAGE_PMD_NR); + clear_huge_page(new_page, vmf->address, HPAGE_PMD_NR); else copy_user_huge_page(new_page, page, haddr, vma, HPAGE_PMD_NR); __SetPageUptodate(new_page); diff --git a/mm/memory.c b/mm/memory.c index e87953775e3c..13ee83b43878 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4417,19 +4417,53 @@ static void clear_gigantic_page(struct page *page, } } void clear_huge_page(struct page *page, - unsigned long addr, unsigned int pages_per_huge_page) + unsigned long addr_hint, unsigned int pages_per_huge_page) { - int i; + int i, n, base, l; + unsigned long addr = addr_hint & + ~(((unsigned long)pages_per_huge_page << PAGE_SHIFT) - 1); if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) { clear_gigantic_page(page, addr, pages_per_huge_page); return; } + /* Clear sub-page to access last to keep its cache lines hot */ might_sleep(); - for (i = 0; i < pages_per_huge_page; i++) { + n = (addr_hint - addr) / PAGE_SIZE; + if (2 * n <= pages_per_huge_page) { + /* If sub-page to access in first half of huge page */ + base = 0; + l = n; + /* Clear sub-pages at the end of huge page */ + for (i = pages_per_huge_page - 1; i >= 2 * n; i--) { + cond_resched(); + clear_user_highpage(page + i, addr + i * PAGE_SIZE); + } + } else { + /* If sub-page to access in second half of huge page */ + base = pages_per_huge_page - 2 * (pages_per_huge_page - n); + l = pages_per_huge_page - n; + /* Clear sub-pages at the begin of huge page */ + for (i = 0; i < base; i++) { + cond_resched(); + clear_user_highpage(page + i, addr + i * PAGE_SIZE); + } + } + /* + * Clear remaining sub-pages in left-right-left-right pattern + * towards the sub-page to access + */ + for (i = 0; i < l; i++) { + int left_idx = base + i; + int right_idx = base + 2 * l - 1 - i; + + cond_resched(); + clear_user_highpage(page + left_idx, + addr + left_idx * PAGE_SIZE); cond_resched(); - clear_user_highpage(page + i, addr + i * PAGE_SIZE); + clear_user_highpage(page + right_idx, + addr + right_idx * PAGE_SIZE); } } |