Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753443Ab1BITyv (ORCPT ); Wed, 9 Feb 2011 14:54:51 -0500 Received: from e4.ny.us.ibm.com ([32.97.182.144]:53005 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752519Ab1BITyU (ORCPT ); Wed, 9 Feb 2011 14:54:20 -0500 Subject: [PATCH 4/5] teach smaps_pte_range() about THP pmds To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Michael J Wolf , Andrea Arcangeli , Dave Hansen , Johannes Weiner , David Rientjes From: Dave Hansen Date: Wed, 09 Feb 2011 11:54:11 -0800 References: <20110209195406.B9F23C9F@kernel> In-Reply-To: <20110209195406.B9F23C9F@kernel> Message-Id: <20110209195411.816D55A7@kernel> X-Content-Scanned: Fidelis XPS MAILER Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1999 Lines: 59 This adds code to explicitly detect and handle pmd_trans_huge() pmds. It then passes HPAGE_SIZE units in to the smap_pte_entry() function instead of PAGE_SIZE. This means that using /proc/$pid/smaps now will no longer cause THPs to be broken down in to small pages. Signed-off-by: Dave Hansen Acked-by: Johannes Weiner Acked-by: David Rientjes --- linux-2.6.git-dave/fs/proc/task_mmu.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff -puN fs/proc/task_mmu.c~teach-smaps_pte_range-about-thp-pmds fs/proc/task_mmu.c --- linux-2.6.git/fs/proc/task_mmu.c~teach-smaps_pte_range-about-thp-pmds 2011-02-09 11:41:43.919557155 -0800 +++ linux-2.6.git-dave/fs/proc/task_mmu.c 2011-02-09 11:41:43.927557149 -0800 @@ -1,5 +1,6 @@ #include #include +#include #include #include #include @@ -7,6 +8,7 @@ #include #include #include +#include #include #include @@ -385,8 +387,16 @@ static int smaps_pte_range(pmd_t *pmd, u pte_t *pte; spinlock_t *ptl; - split_huge_page_pmd(walk->mm, pmd); - + if (pmd_trans_huge(*pmd)) { + if (pmd_trans_splitting(*pmd)) { + spin_unlock(&walk->mm->page_table_lock); + wait_split_huge_page(vma->anon_vma, pmd); + spin_lock(&walk->mm->page_table_lock); + } else { + smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_SIZE, walk); + return 0; + } + } pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); for (; addr != end; pte++, addr += PAGE_SIZE) smaps_pte_entry(*pte, addr, PAGE_SIZE, walk); _ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/