From patchwork Thu Mar 16 18:24:34 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 9629205 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id EAC43604AA for ; Thu, 16 Mar 2017 18:35:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E1B1C2867F for ; Thu, 16 Mar 2017 18:35:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D585228682; Thu, 16 Mar 2017 18:35:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 58A142867F for ; Thu, 16 Mar 2017 18:35:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752865AbdCPSfj (ORCPT ); Thu, 16 Mar 2017 14:35:39 -0400 Received: from foss.arm.com ([217.140.101.70]:38132 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752202AbdCPSfi (ORCPT ); Thu, 16 Mar 2017 14:35:38 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D2F8C687; Thu, 16 Mar 2017 11:27:04 -0700 (PDT) Received: from e107814-lin.cambridge.arm.com (e107814-lin.cambridge.arm.com [10.1.206.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id CE7D83F220; Thu, 16 Mar 2017 11:27:03 -0700 (PDT) From: Suzuki K Poulose To: kvmarm@lists.cs.columbia.edu Cc: linux-arm-kernel@lists.infradead.org, christoffer.dall@linaro.org, marc.zyngier@arm.com, kvm@vger.kernel.org, Suzuki K Poulose Subject: [PATCH] kvm: arm/arm64: Simplify lock relaxation in stage2_wp_range Date: Thu, 16 Mar 2017 18:24:34 +0000 Message-Id: <1489688674-17692-1-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.7.4 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Marc Zyngier Add checks to make sure that kvm->mmu_lock is held while calling stage2_wp_range. Also avoid explicit checks already done by cond_resched_lock(). Signed-off-by: Marc Zyngier [ Added assert_spin_locked check ] Signed-off-by: Suzuki K Poulose Reviewed-by: Christoffer Dall --- arch/arm/kvm/mmu.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 7628ef1..37e67f5 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1162,6 +1162,8 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) pgd_t *pgd; phys_addr_t next; + assert_spin_locked(&kvm->mmu_lock); + pgd = kvm->arch.pgd + stage2_pgd_index(addr); do { /* @@ -1171,8 +1173,7 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) * CONFIG_LOCKDEP. Additionally, holding the lock too long * will also starve other vCPUs. */ - if (need_resched() || spin_needbreak(&kvm->mmu_lock)) - cond_resched_lock(&kvm->mmu_lock); + cond_resched_lock(&kvm->mmu_lock); next = stage2_pgd_addr_end(addr, end); if (stage2_pgd_present(*pgd))