From patchwork Fri Mar 26 02:19:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12165537 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6959DC433DB for ; Fri, 26 Mar 2021 02:21:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 36C71619DC for ; Fri, 26 Mar 2021 02:21:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231327AbhCZCUr (ORCPT ); Thu, 25 Mar 2021 22:20:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230327AbhCZCUN (ORCPT ); Thu, 25 Mar 2021 22:20:13 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86B88C061761 for ; Thu, 25 Mar 2021 19:20:13 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id x8so8408426ybo.6 for ; Thu, 25 Mar 2021 19:20:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=xb8DgI2xFcrM/12UvqDPQlPXHEZwzPOiZzDwlsIie/g=; b=LTA+FlztlbawA45c1WTNtB0+0k4zDG2JNcBSVgOBw6hAgXeXfNjZbqxa0273lIWLNe ttjcg3fq+z634BQAWTxUlSsrRwNAaP+NP0BoTVohovvNTClDA7Atl31Oegy0JstB9ddH QquMjA9vYXTD8sE0ETK+TS3DQ0/9PyHdPbhasPovVlJc6LBQ4ZzAIKNbkbAQxLe+0uY9 5ul5DAL52znGITYaaSnYG1czEu70soT/ovFzF22WuRsZzZM2LTU5TaSfaNlMMeAYoxEh nxkXSMEvdAqjZ2IhpJWyzFxM0kGdcqc6rH1PgDdXHrzIHZH3KWpk77UxwCuoas+sWLNA Nygg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=xb8DgI2xFcrM/12UvqDPQlPXHEZwzPOiZzDwlsIie/g=; b=UPh9LKPSLS8qczQj9SZPnCFthZLlbf9HWqDUOSravNZ5mWolZYupBNt6sPLyv08Hn1 EgU7w3JJ1flZ2WDKp+ht9GL18iw2WXoUIsmBwUNyJ+XI4VFANrLTZN6CuUOIGP1tjFn1 fyoUw6PUhiUV0Qgq9wAcicNRPV2RnKT0wnlJWXx3fmT4RRMOPfw/Cwst2qfeIUqaemVp XbiLuFjXWlL9oL/AOjfkgxIRb+48qOY/IKEJAA+P3WkfW9/Tld7Uj2ffWn9ZoNEatVjg bNov9Gu57pUbTsPtEaQhlvabMjw170FA6MD4TxR2Dvqg/ppISK70xNDk/+3NSz2nJeSv MTZg== X-Gm-Message-State: AOAM531NosBHzA8ANh3vzSY4chl/3DB329HlbDmHI2WVdVXWNqz3bEzV 3gS+0Uuf51EfRqC3LPfdFTrHOrMSpSk= X-Google-Smtp-Source: ABdhPJzT/d6MruEkvrArmoOcIHLexgvlTJlZNDyv9Tx14134QiRzKCyIxhCXc8QGkX5T07WTvqrR6kS/xTk= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:f:10:b1bb:fab2:7ef5:fc7d]) (user=seanjc job=sendgmr) by 2002:a25:37c1:: with SMTP id e184mr16469856yba.260.1616725212722; Thu, 25 Mar 2021 19:20:12 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 25 Mar 2021 19:19:40 -0700 In-Reply-To: <20210326021957.1424875-1-seanjc@google.com> Message-Id: <20210326021957.1424875-2-seanjc@google.com> Mime-Version: 1.0 References: <20210326021957.1424875-1-seanjc@google.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH 01/18] KVM: x86/mmu: Coalesce TDP MMU TLB flushes when zapping collapsible SPTEs From: Sean Christopherson To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Paolo Bonzini Cc: James Morse , Julien Thierry , Suzuki K Poulose , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gardon Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When zapping collapsible SPTEs across multiple roots, gather pending flushes and perform a single remote TLB flush at the end, as opposed to flushing after processing every root. Note, flush may be cleared by the result of zap_collapsible_spte_range(). This is intended and correct, e.g. yielding may have serviced a prior pending flush. Cc: Ben Gardon Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/tdp_mmu.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 08667e3cf091..463f1be6ff0d 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1278,21 +1278,21 @@ void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm, * Clear leaf entries which could be replaced by large mappings, for * GFNs within the slot. */ -static void zap_collapsible_spte_range(struct kvm *kvm, +static bool zap_collapsible_spte_range(struct kvm *kvm, struct kvm_mmu_page *root, - struct kvm_memory_slot *slot) + struct kvm_memory_slot *slot, + bool flush) { gfn_t start = slot->base_gfn; gfn_t end = start + slot->npages; struct tdp_iter iter; kvm_pfn_t pfn; - bool spte_set = false; rcu_read_lock(); tdp_root_for_each_pte(iter, root, start, end) { - if (tdp_mmu_iter_cond_resched(kvm, &iter, spte_set)) { - spte_set = false; + if (tdp_mmu_iter_cond_resched(kvm, &iter, flush)) { + flush = false; continue; } @@ -1308,12 +1308,12 @@ static void zap_collapsible_spte_range(struct kvm *kvm, tdp_mmu_set_spte(kvm, &iter, 0); - spte_set = true; + flush = true; } rcu_read_unlock(); - if (spte_set) - kvm_flush_remote_tlbs(kvm); + + return flush; } /* @@ -1324,6 +1324,7 @@ void kvm_tdp_mmu_zap_collapsible_sptes(struct kvm *kvm, struct kvm_memory_slot *slot) { struct kvm_mmu_page *root; + bool flush = false; int root_as_id; for_each_tdp_mmu_root_yield_safe(kvm, root) { @@ -1331,8 +1332,11 @@ void kvm_tdp_mmu_zap_collapsible_sptes(struct kvm *kvm, if (root_as_id != slot->as_id) continue; - zap_collapsible_spte_range(kvm, root, slot); + flush = zap_collapsible_spte_range(kvm, root, slot, flush); } + + if (flush) + kvm_flush_remote_tlbs(kvm); } /*