From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id BAE6E620084 for ; Thu, 1 Apr 2010 20:46:21 -0400 (EDT) Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [PATCH 38 of 41] mincore transparent hugepage support Message-Id: In-Reply-To: References: Date: Fri, 02 Apr 2010 02:42:05 +0200 From: Andrea Arcangeli Sender: owner-linux-mm@kvack.org To: linux-mm@kvack.org, Andrew Morton Cc: Marcelo Tosatti , Adam Litke , Avi Kivity , Izik Eidus , Hugh Dickins , Nick Piggin , Rik van Riel , Mel Gorman , Dave Hansen , Benjamin Herrenschmidt , Ingo Molnar , Mike Travis , KAMEZAWA Hiroyuki , Christoph Lameter , Chris Wright , bpicco@redhat.com, KOSAKI Motohiro , Balbir Singh , Arnd Bergmann , "Michael S. Tsirkin" , Peter Zijlstra , Johannes Weiner , Daisuke Nishimura List-ID: From: Johannes Weiner Handle transparent huge page pmd entries natively instead of splitting them into subpages. Signed-off-by: Johannes Weiner Signed-off-by: Andrea Arcangeli Reviewed-by: Rik van Riel --- diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -19,6 +19,9 @@ extern struct page *follow_trans_huge_pm extern int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, pmd_t *pmd); +extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + unsigned char *vec); enum transparent_hugepage_flag { TRANSPARENT_HUGEPAGE_FLAG, diff --git a/mm/huge_memory.c b/mm/huge_memory.c --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -936,6 +936,31 @@ int zap_huge_pmd(struct mmu_gather *tlb, return ret; } +int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ + int ret = 0; + + spin_lock(&vma->vm_mm->page_table_lock); + if (likely(pmd_trans_huge(*pmd))) { + ret = !pmd_trans_splitting(*pmd); + spin_unlock(&vma->vm_mm->page_table_lock); + if (unlikely(!ret)) + wait_split_huge_page(vma->anon_vma, pmd); + else { + /* + * All logical pages in the range are present + * if backed by a huge page. + */ + memset(vec, 1, (end - addr) >> PAGE_SHIFT); + } + } else + spin_unlock(&vma->vm_mm->page_table_lock); + + return ret; +} + pmd_t *page_check_address_pmd(struct page *page, struct mm_struct *mm, unsigned long address, diff --git a/mm/mincore.c b/mm/mincore.c --- a/mm/mincore.c +++ b/mm/mincore.c @@ -154,7 +154,13 @@ static void mincore_pmd_range(struct vm_ pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); - split_huge_page_pmd(vma->vm_mm, pmd); + if (pmd_trans_huge(*pmd)) { + if (mincore_huge_pmd(vma, pmd, addr, next, vec)) { + vec += (next - addr) >> PAGE_SHIFT; + continue; + } + /* fall through */ + } if (pmd_none_or_clear_bad(pmd)) mincore_unmapped_range(vma, addr, next, vec); else -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org