From nobody Sat Feb 7 03:07:54 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D555C47071 for ; Sat, 18 Nov 2023 02:33:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234814AbjKRCdP (ORCPT ); Fri, 17 Nov 2023 21:33:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232862AbjKRCdK (ORCPT ); Fri, 17 Nov 2023 21:33:10 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE2D510EC for ; Fri, 17 Nov 2023 18:33:06 -0800 (PST) Received: from dggpemm100001.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4SXHm50vr9zsR5c; Sat, 18 Nov 2023 10:29:41 +0800 (CST) Received: from localhost.localdomain (10.175.112.125) by dggpemm100001.china.huawei.com (7.185.36.93) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Sat, 18 Nov 2023 10:33:04 +0800 From: Kefeng Wang To: Andrew Morton CC: , , Matthew Wilcox , David Hildenbrand , Sidhartha Kumar , Vishal Moola , Kefeng Wang Subject: [PATCH v3 4/5] mm: memory: use a folio in do_cow_fault() Date: Sat, 18 Nov 2023 10:32:31 +0800 Message-ID: <20231118023232.1409103-5-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20231118023232.1409103-1-wangkefeng.wang@huawei.com> References: <20231118023232.1409103-1-wangkefeng.wang@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm100001.china.huawei.com (7.185.36.93) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Use folio_prealloc() helper and convert to use a folio in do_cow_fault(), which save five compound_head() calls. Reviewed-by: Vishal Moola (Oracle) Signed-off-by: Kefeng Wang --- mm/memory.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index 93c9ed01fc86..868a2fc54549 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4739,6 +4739,7 @@ static vm_fault_t do_read_fault(struct vm_fault *vmf) static vm_fault_t do_cow_fault(struct vm_fault *vmf) { struct vm_area_struct *vma =3D vmf->vma; + struct folio *folio; vm_fault_t ret; =20 ret =3D vmf_can_call_fault(vmf); @@ -4747,16 +4748,11 @@ static vm_fault_t do_cow_fault(struct vm_fault *vmf) if (ret) return ret; =20 - vmf->cow_page =3D alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vmf->address); - if (!vmf->cow_page) + folio =3D folio_prealloc(vma->vm_mm, vma, vmf->address, false); + if (!folio) return VM_FAULT_OOM; =20 - if (mem_cgroup_charge(page_folio(vmf->cow_page), vma->vm_mm, - GFP_KERNEL)) { - put_page(vmf->cow_page); - return VM_FAULT_OOM; - } - folio_throttle_swaprate(page_folio(vmf->cow_page), GFP_KERNEL); + vmf->cow_page =3D &folio->page; =20 ret =3D __do_fault(vmf); if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY))) @@ -4765,7 +4761,7 @@ static vm_fault_t do_cow_fault(struct vm_fault *vmf) return ret; =20 copy_user_highpage(vmf->cow_page, vmf->page, vmf->address, vma); - __SetPageUptodate(vmf->cow_page); + __folio_mark_uptodate(folio); =20 ret |=3D finish_fault(vmf); unlock_page(vmf->page); @@ -4774,7 +4770,7 @@ static vm_fault_t do_cow_fault(struct vm_fault *vmf) goto uncharge_out; return ret; uncharge_out: - put_page(vmf->cow_page); + folio_put(folio); return ret; } =20 --=20 2.27.0