From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932447AbcBAN0z (ORCPT ); Mon, 1 Feb 2016 08:26:55 -0500 Received: from mga09.intel.com ([134.134.136.24]:16285 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932225AbcBAN0x (ORCPT ); Mon, 1 Feb 2016 08:26:53 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,380,1449561600"; d="scan'208";a="893780818" From: "Kirill A. Shutemov" To: Andrew Morton , Dmitry Vyukov Cc: Vlastimil Babka , David Rientjes , Naoya Horiguchi , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCH 2/2] mempolicy: do not try to queue pages from !vma_migratable() Date: Mon, 1 Feb 2016 16:26:09 +0300 Message-Id: <1454333169-121369-3-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1454333169-121369-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1454333169-121369-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Maybe I miss some point, but I don't see a reason why we try to queue pages from non migratable VMAs. The only case when we can queue pages from such VMA is MPOL_MF_STRICT plus MPOL_MF_MOVE or MPOL_MF_MOVE_ALL for VMA which has pages on LRU, but gfp mask is not sutable for migaration (see mapping_gfp_mask() check in vma_migratable()). That's looks like a bug to me. Let's filter out non-migratable vma at start of queue_pages_test_walk() and go to queue_pages_pte_range() only if MPOL_MF_MOVE or MPOL_MF_MOVE_ALL flag is set. Signed-off-by: Kirill A. Shutemov --- mm/mempolicy.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 27d135408a22..4c4187c0e1de 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -548,8 +548,7 @@ retry: goto retry; } - if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) - migrate_page_add(page, qp->pagelist, flags); + migrate_page_add(page, qp->pagelist, flags); } pte_unmap_unlock(pte - 1, ptl); cond_resched(); @@ -625,7 +624,7 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end, unsigned long endvma = vma->vm_end; unsigned long flags = qp->flags; - if (vma->vm_flags & VM_PFNMAP) + if (!vma_migratable(vma)) return 1; if (endvma > end) @@ -644,16 +643,13 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end, if (flags & MPOL_MF_LAZY) { /* Similar to task_numa_work, skip inaccessible VMAs */ - if (vma_migratable(vma) && - vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)) + if (vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)) change_prot_numa(vma, start, endvma); return 1; } - if ((flags & MPOL_MF_STRICT) || - ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) && - vma_migratable(vma))) - /* queue pages from current vma */ + /* queue pages from current vma */ + if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) return 0; return 1; } -- 2.7.0