Messages in this thread Patch in this message | | | From | Alex Thorlton <> | Subject | [PATCH 5/8] mm: make clear_huge_page cache clear only around the fault address | Date | Fri, 16 Aug 2013 09:34:01 -0500 |
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--- mm/memory.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c index 69a5a38..17d61f0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4231,18 +4231,35 @@ EXPORT_SYMBOL(might_fault); #endif #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS) + +#ifndef ARCH_HAS_USER_NOCACHE +#define ARCH_HAS_USER_NOCACHE 0 +#endif + +#if ARCH_HAS_USER_NOCACHE == 0 +#define clear_user_highpage_nocache clear_user_highpage +#endif + static void clear_gigantic_page(struct page *page, unsigned long addr, unsigned int pages_per_huge_page) { int i; struct page *p = page; + unsigned long vaddr; + unsigned long haddr = addr & HPAGE_PMD_MASK; + int target = (addr - haddr) >> PAGE_SHIFT; might_sleep(); + vaddr = haddr; for (i = 0; i < pages_per_huge_page; i++, p = mem_map_next(p, page, i)) { cond_resched(); - clear_user_highpage(p, addr + i * PAGE_SIZE); + vaddr = haddr + i*PAGE_SIZE; + if (!ARCH_HAS_USER_NOCACHE || i == target) + clear_user_highpage(p, vaddr); + else + clear_user_highpage_nocache(p, vaddr); } } void clear_huge_page(struct page *page, @@ -4250,6 +4267,8 @@ void clear_huge_page(struct page *page, { int i; unsigned long haddr = addr & HPAGE_PMD_MASK; + unsigned long vaddr; + int target = (addr - haddr) >> PAGE_SHIFT; if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) { clear_gigantic_page(page, haddr, pages_per_huge_page); @@ -4257,9 +4276,14 @@ void clear_huge_page(struct page *page, } might_sleep(); + vaddr = haddr; for (i = 0; i < pages_per_huge_page; i++) { cond_resched(); - clear_user_highpage(page + i, haddr + i * PAGE_SIZE); + vaddr = haddr + i*PAGE_SIZE; + if (!ARCH_HAS_USER_NOCACHE || i == target) + clear_user_highpage(page + i, vaddr); + else + clear_user_highpage_nocache(page + i, vaddr); } } -- 1.7.12.4
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