From patchwork Fri Nov 20 08:43:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takuya Yoshikawa X-Patchwork-Id: 7665601 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4B2C2BF90C for ; Fri, 20 Nov 2015 08:30:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7750320497 for ; Fri, 20 Nov 2015 08:30:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF52720494 for ; Fri, 20 Nov 2015 08:30:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935049AbbKTIaR (ORCPT ); Fri, 20 Nov 2015 03:30:17 -0500 Received: from tama500.ecl.ntt.co.jp ([129.60.39.148]:36750 "EHLO tama500.ecl.ntt.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934753AbbKTIaP (ORCPT ); Fri, 20 Nov 2015 03:30:15 -0500 Received: from vc1.ecl.ntt.co.jp (vc1.ecl.ntt.co.jp [129.60.86.153]) by tama500.ecl.ntt.co.jp (8.13.8/8.13.8) with ESMTP id tAK8UA81031630; Fri, 20 Nov 2015 17:30:10 +0900 Received: from vc1.ecl.ntt.co.jp (localhost [127.0.0.1]) by vc1.ecl.ntt.co.jp (Postfix) with ESMTP id 9E13A5F612; Fri, 20 Nov 2015 17:30:10 +0900 (JST) Received: from imail2.m.ecl.ntt.co.jp (imail2.m.ecl.ntt.co.jp [129.60.5.247]) by vc1.ecl.ntt.co.jp (Postfix) with ESMTP id 8FC105F611; Fri, 20 Nov 2015 17:30:10 +0900 (JST) Received: from localhost.localdomain ([129.60.241.174]) by imail2.m.ecl.ntt.co.jp (8.13.8/8.13.8) with SMTP id tAK8UAIK013835; Fri, 20 Nov 2015 17:30:10 +0900 Date: Fri, 20 Nov 2015 17:43:13 +0900 From: Takuya Yoshikawa To: pbonzini@redhat.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, mtosatti@redhat.com, guangrong.xiao@linux.intel.com Subject: [PATCH 03/10] KVM: x86: MMU: Add helper function to clear a bit in unsync child bitmap Message-Id: <20151120174313.de78aef47c94c86e2368a64f@lab.ntt.co.jp> In-Reply-To: <20151120174005.9880b89f54eee2cec2422da5@lab.ntt.co.jp> References: <20151120174005.9880b89f54eee2cec2422da5@lab.ntt.co.jp> X-Mailer: Sylpheed 3.4.2 (GTK+ 2.24.28; x86_64-redhat-linux-gnu) Mime-Version: 1.0 X-TM-AS-MML: disable Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Both __mmu_unsync_walk() and mmu_pages_clear_parents() have three line code which clears a bit in the unsync child bitmap; the former places it inside a loop block and uses a few goto statements to jump to it. A new helper function, clear_unsync_child_bit(), makes the code cleaner. Signed-off-by: Takuya Yoshikawa --- arch/x86/kvm/mmu.c | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8a1593f..9832bc9 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1809,6 +1809,13 @@ static int mmu_pages_add(struct kvm_mmu_pages *pvec, struct kvm_mmu_page *sp, return (pvec->nr == KVM_PAGE_ARRAY_NR); } +static inline void clear_unsync_child_bit(struct kvm_mmu_page *sp, int idx) +{ + --sp->unsync_children; + WARN_ON((int)sp->unsync_children < 0); + __clear_bit(idx, sp->unsync_child_bitmap); +} + static int __mmu_unsync_walk(struct kvm_mmu_page *sp, struct kvm_mmu_pages *pvec) { @@ -1818,8 +1825,10 @@ static int __mmu_unsync_walk(struct kvm_mmu_page *sp, struct kvm_mmu_page *child; u64 ent = sp->spt[i]; - if (!is_shadow_present_pte(ent) || is_large_pte(ent)) - goto clear_child_bitmap; + if (!is_shadow_present_pte(ent) || is_large_pte(ent)) { + clear_unsync_child_bit(sp, i); + continue; + } child = page_header(ent & PT64_BASE_ADDR_MASK); @@ -1828,28 +1837,21 @@ static int __mmu_unsync_walk(struct kvm_mmu_page *sp, return -ENOSPC; ret = __mmu_unsync_walk(child, pvec); - if (!ret) - goto clear_child_bitmap; - else if (ret > 0) + if (!ret) { + clear_unsync_child_bit(sp, i); + continue; + } else if (ret > 0) { nr_unsync_leaf += ret; - else + } else return ret; } else if (child->unsync) { nr_unsync_leaf++; if (mmu_pages_add(pvec, child, i)) return -ENOSPC; } else - goto clear_child_bitmap; - - continue; - -clear_child_bitmap: - __clear_bit(i, sp->unsync_child_bitmap); - sp->unsync_children--; - WARN_ON((int)sp->unsync_children < 0); + clear_unsync_child_bit(sp, i); } - return nr_unsync_leaf; } @@ -2012,9 +2014,7 @@ static void mmu_pages_clear_parents(struct mmu_page_path *parents) if (!sp) return; - --sp->unsync_children; - WARN_ON((int)sp->unsync_children < 0); - __clear_bit(idx, sp->unsync_child_bitmap); + clear_unsync_child_bit(sp, idx); level++; } while (level < PT64_ROOT_LEVEL-1 && !sp->unsync_children); }