From mboxrd@z Thu Jan 1 00:00:00 1970 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 05D57C0502C for ; Tue, 30 Aug 2022 19:51:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231726AbiH3Tvu (ORCPT ); Tue, 30 Aug 2022 15:51:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55310 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231587AbiH3Tvp (ORCPT ); Tue, 30 Aug 2022 15:51:45 -0400 Received: from out0.migadu.com (out0.migadu.com [94.23.1.103]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45C757E316; Tue, 30 Aug 2022 12:51:44 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1661889102; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BmHJR6N3rI3NqVKRQnsaZiBFli5RmIY4C8X+Uix5thU=; b=eBaq5OcegB50cLDgGEiduR4Tgk5pLMtHfEruHLpo036HKXFf0YTXH2bWlsFFUmU/6mHlgb 4V4yxrZtBF7lSii3YCwzkHciBjKh7H1kMwVqh8gok5JQ6GRUH7NmjinsnU6ud9D2trTwEX A/qAC0OBx34lJZlbrfIE1UPaqv+pv/k= From: Oliver Upton To: Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Oliver Upton , Catalin Marinas , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Quentin Perret , Ricardo Koller , Reiji Watanabe , David Matlack , Ben Gardon , Paolo Bonzini , Gavin Shan , Peter Xu , Sean Christopherson , linux-kernel@vger.kernel.org Subject: [PATCH 12/14] KVM: arm64: Make leaf->leaf PTE changes parallel-aware Date: Tue, 30 Aug 2022 19:51:32 +0000 Message-Id: <20220830195132.964800-1-oliver.upton@linux.dev> In-Reply-To: <20220830194132.962932-1-oliver.upton@linux.dev> References: <20220830194132.962932-1-oliver.upton@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Convert stage2_map_walker_try_leaf() to use the new break-before-make helpers, thereby making the handler parallel-aware. As before, avoid the break-before-make if recreating the existing mapping. Additionally, retry execution if another vCPU thread is modifying the same PTE. Signed-off-by: Oliver Upton --- arch/arm64/kvm/hyp/pgtable.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 71ae96608752..de1d352657d0 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -829,18 +829,17 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, else new = kvm_init_invalid_leaf_owner(data->owner_id); - if (stage2_pte_is_counted(old)) { - /* - * Skip updating the PTE if we are trying to recreate the exact - * same mapping or only change the access permissions. Instead, - * the vCPU will exit one more time from guest if still needed - * and then go through the path of relaxing permissions. - */ - if (!stage2_pte_needs_update(old, new)) - return -EAGAIN; + /* + * Skip updating the PTE if we are trying to recreate the exact + * same mapping or only change the access permissions. Instead, + * the vCPU will exit one more time from guest if still needed + * and then go through the path of relaxing permissions. + */ + if (!stage2_pte_needs_update(old, new)) + return -EAGAIN; - stage2_put_pte(ptep, data->mmu, addr, level, mm_ops); - } + if (!stage2_try_break_pte(ptep, old, addr, level, data)) + return -EAGAIN; /* Perform CMOs before installation of the guest stage-2 PTE */ if (mm_ops->dcache_clean_inval_poc && stage2_pte_cacheable(pgt, new)) @@ -850,9 +849,8 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, if (mm_ops->icache_inval_pou && stage2_pte_executable(new)) mm_ops->icache_inval_pou(kvm_pte_follow(new, mm_ops), granule); - smp_store_release(ptep, new); - if (stage2_pte_is_counted(new)) - mm_ops->get_page(ptep); + stage2_make_pte(ptep, old, new, data); + if (kvm_phys_is_valid(phys)) data->phys += granule; return 0; -- 2.37.2.672.g94769d06f0-goog