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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E037AC433F5 for ; Thu, 4 Nov 2021 00:29:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7D23611CB for ; Thu, 4 Nov 2021 00:29:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233703AbhKDAcA (ORCPT ); Wed, 3 Nov 2021 20:32:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233490AbhKDA3X (ORCPT ); Wed, 3 Nov 2021 20:29:23 -0400 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F19F8C061714 for ; Wed, 3 Nov 2021 17:26:45 -0700 (PDT) Received: by mail-pf1-x449.google.com with SMTP id 2-20020aa79102000000b0044c216dd8ecso2322387pfh.18 for ; Wed, 03 Nov 2021 17:26:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=WFKHlikOkpZJpdiLsH4aJihxblDmBHivJrGM8NlUt9c=; b=CRXCwBEqUdB8xBBWvbn9rvEyj5xPoJz0Yiq4O9bYP8Cnw9QN2e+/rU9Z5zno6u5DVK hNycH7Nu/XPtuVsGfPUbSSTGueoe3SJ6D/+uQvX8yXVdBR6JZwONNcY2XuE+tNblfPrg DzYe3VWSE9iz+kLrReWCKtPXc8mvDFxOyEZwsrJmqEqT2dddKgFB7DSFo4206QBqUe3l k94nG8IGw8Qk397gTW+mXweZuq2D9/OlhQu3qaAukGk74Ifow4G0x6SSEWRb7kyDOXHM mtFt8FUjKSwLn45cNEc6CmGXWE+Jks8EonoUKThzOIBSyaz6+hVlcyMpoJKcO82sckqF 5Fzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=WFKHlikOkpZJpdiLsH4aJihxblDmBHivJrGM8NlUt9c=; b=E/ycOcci9RBNrMqjvvFLZs/SYse5na6ynkWYkIy1p4Tsmbrgm8fzizjCHOwFe0vWL3 GohsTiCxROQVojBDRbtval9GqH84nvcDMgeHc4fyX+G/LOSrj+qZNDA5edup7Nw+eXov kJ1DpOx1r4RYKnTqGxTCjKEBNZnqvPU0aMY82c7vtDS2uvq7uQpL1H8N62MZ83YOIFxw OcMvdSTKK4t3ZjgG4ZoQi4n+Z5i2zt25Hga0dyHmYR/p7F80+G/4qXMxjoD3UUdIdg+L dFM+yTTfCpnWuKXWESdDpQdVTtqvv3YtpKc68Ss9r6dSQMveKBOwBdiMtcFLQDVLpxU+ 5C+w== X-Gm-Message-State: AOAM530q7WM9X/1oK3P5Ame7jSHfEeSdAfE0LbJ0LzyBoGyHBJksvJrk fjSjZe4had/xdBMgQC5MlbV6MD9iWAw= X-Google-Smtp-Source: ABdhPJxoDZvqdkusy2MitxT+1dAwOu5YXFxH0crl6GBFlwKLx55yi8xQIaLV4Wu5oujGScgLca++ESEBh4I= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a05:6a00:1994:b0:47e:64e5:a1b3 with SMTP id d20-20020a056a00199400b0047e64e5a1b3mr42939171pfl.64.1635985605387; Wed, 03 Nov 2021 17:26:45 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 4 Nov 2021 00:25:28 +0000 In-Reply-To: <20211104002531.1176691-1-seanjc@google.com> Message-Id: <20211104002531.1176691-28-seanjc@google.com> Mime-Version: 1.0 References: <20211104002531.1176691-1-seanjc@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [PATCH v5.5 27/30] KVM: Optimize gfn lookup in kvm_zap_gfn_range() From: Sean Christopherson To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Atish Patra , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , 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, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Ben Gardon , "Maciej S . Szmigiero" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Maciej S. Szmigiero Introduce a memslots gfn upper bound operation and use it to optimize kvm_zap_gfn_range(). This way this handler can do a quick lookup for intersecting gfns and won't have to do a linear scan of the whole memslot set. Signed-off-by: Maciej S. Szmigiero Not-signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 11 +++++-- include/linux/kvm_host.h | 69 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 09ff0ccaa203..14e41278c069 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5714,16 +5714,20 @@ static bool __kvm_zap_rmaps(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) { const struct kvm_memory_slot *memslot; struct kvm_memslots *slots; + struct rb_node *node; bool flush = false; gfn_t start, end; - int i, bkt; + int i, idx; if (!kvm_memslots_have_rmaps(kvm)) return flush; for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, bkt, slots) { + idx = slots->node_idx; + + kvm_for_each_memslot_in_gfn_range(node, slots, gfn_start, gfn_end) { + memslot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); start = max(gfn_start, memslot->base_gfn); end = min(gfn_end, memslot->base_gfn + memslot->npages); if (start >= end) @@ -5747,6 +5751,9 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) bool flush; int i; + if (WARN_ON_ONCE(gfn_end <= gfn_start)) + return; + write_lock(&kvm->mmu_lock); kvm_inc_notifier_count(kvm, gfn_start, gfn_end); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6888f3c2e04b..810a5b958697 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -832,6 +832,75 @@ struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) return NULL; } +static inline +struct rb_node *kvm_memslots_gfn_upper_bound(struct kvm_memslots *slots, gfn_t gfn) +{ + int idx = slots->node_idx; + struct rb_node *node, *result = NULL; + + for (node = slots->gfn_tree.rb_node; node; ) { + struct kvm_memory_slot *slot; + + slot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); + if (gfn < slot->base_gfn) { + result = node; + node = node->rb_left; + } else + node = node->rb_right; + } + + return result; +} + +static inline +struct rb_node *kvm_for_each_in_gfn_first(struct kvm_memslots *slots, gfn_t start) +{ + struct rb_node *node; + + /* + * Find the slot with the lowest gfn that can possibly intersect with + * the range, so we'll ideally have slot start <= range start + */ + node = kvm_memslots_gfn_upper_bound(slots, start); + if (node) { + struct rb_node *pnode; + + /* + * A NULL previous node means that the very first slot + * already has a higher start gfn. + * In this case slot start > range start. + */ + pnode = rb_prev(node); + if (pnode) + node = pnode; + } else { + /* a NULL node below means no slots */ + node = rb_last(&slots->gfn_tree); + } + + return node; +} + +static inline +bool kvm_for_each_in_gfn_no_more(struct kvm_memslots *slots, struct rb_node *node, gfn_t end) +{ + struct kvm_memory_slot *memslot; + + memslot = container_of(node, struct kvm_memory_slot, gfn_node[slots->node_idx]); + + /* + * If this slot starts beyond or at the end of the range so does + * every next one + */ + return memslot->base_gfn >= end; +} + +/* Iterate over each memslot *possibly* intersecting [start, end) range */ +#define kvm_for_each_memslot_in_gfn_range(node, slots, start, end) \ + for (node = kvm_for_each_in_gfn_first(slots, start); \ + node && !kvm_for_each_in_gfn_no_more(slots, node, end); \ + node = rb_next(node)) \ + /* * KVM_SET_USER_MEMORY_REGION ioctl allows the following operations: * - create a new memory slot -- 2.33.1.1089.g2158813163f-goog 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C83C4C433EF for ; Thu, 4 Nov 2021 00:26:52 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 7D7C4611C7 for ; Thu, 4 Nov 2021 00:26:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7D7C4611C7 Authentication-Results: mail.kernel.org; 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s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=WFKHlikOkpZJpdiLsH4aJihxblDmBHivJrGM8NlUt9c=; b=vx5TeeDghd8l8fiGKKxKpWdQtwY84+fW5GED05A5GkwdfJy8L2U8j44G6NeSmWBtrw U8GTxXOP9oGQiMYh0dAGeFmuvJPCW66xyJTp0cegdCboYn6f7O0ITq2/m3t+q8U2339z LsMu2iyhV8eDoAja9ZUkOfkkEWYWIsb4wfrE17f7ws67uazR/yZ6PF7O4vtNWW7gpo6U BKpzQbUGwK7ZkTdOEdpXwI07TEPO8MuU71p6+y7USltwnfT8zsS0mcGIAMfi1uvRK7/y iYF0czT8sxlniLlbmku/MQFGJe9zjBJIFyY4T5TH0RYS1e+3OqPk5Kgmx92QocBJilMO AGpw== X-Gm-Message-State: AOAM531UW5tAfRCjc4gur0xW/Mwkvz2wkBFHR+BplA3bnaYbmAFMcdTR CXh09RDzyixUWcm6PuEhsgt9Gke9FUA= X-Google-Smtp-Source: ABdhPJxoDZvqdkusy2MitxT+1dAwOu5YXFxH0crl6GBFlwKLx55yi8xQIaLV4Wu5oujGScgLca++ESEBh4I= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a05:6a00:1994:b0:47e:64e5:a1b3 with SMTP id d20-20020a056a00199400b0047e64e5a1b3mr42939171pfl.64.1635985605387; Wed, 03 Nov 2021 17:26:45 -0700 (PDT) Date: Thu, 4 Nov 2021 00:25:28 +0000 In-Reply-To: <20211104002531.1176691-1-seanjc@google.com> Message-Id: <20211104002531.1176691-28-seanjc@google.com> Mime-Version: 1.0 References: <20211104002531.1176691-1-seanjc@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [PATCH v5.5 27/30] KVM: Optimize gfn lookup in kvm_zap_gfn_range() From: Sean Christopherson To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: Wanpeng Li , kvm@vger.kernel.org, David Hildenbrand , linux-kernel@vger.kernel.org, Atish Patra , Ben Gardon , "Maciej S . Szmigiero" , Claudio Imbrenda , linux-riscv@lists.infradead.org, Joerg Roedel , kvmarm@lists.cs.columbia.edu, kvm-ppc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Jim Mattson , Cornelia Huck , linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org, Vitaly Kuznetsov X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list Reply-To: Sean Christopherson List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu From: Maciej S. Szmigiero Introduce a memslots gfn upper bound operation and use it to optimize kvm_zap_gfn_range(). This way this handler can do a quick lookup for intersecting gfns and won't have to do a linear scan of the whole memslot set. Signed-off-by: Maciej S. Szmigiero Not-signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 11 +++++-- include/linux/kvm_host.h | 69 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 09ff0ccaa203..14e41278c069 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5714,16 +5714,20 @@ static bool __kvm_zap_rmaps(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) { const struct kvm_memory_slot *memslot; struct kvm_memslots *slots; + struct rb_node *node; bool flush = false; gfn_t start, end; - int i, bkt; + int i, idx; if (!kvm_memslots_have_rmaps(kvm)) return flush; for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, bkt, slots) { + idx = slots->node_idx; + + kvm_for_each_memslot_in_gfn_range(node, slots, gfn_start, gfn_end) { + memslot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); start = max(gfn_start, memslot->base_gfn); end = min(gfn_end, memslot->base_gfn + memslot->npages); if (start >= end) @@ -5747,6 +5751,9 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) bool flush; int i; + if (WARN_ON_ONCE(gfn_end <= gfn_start)) + return; + write_lock(&kvm->mmu_lock); kvm_inc_notifier_count(kvm, gfn_start, gfn_end); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6888f3c2e04b..810a5b958697 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -832,6 +832,75 @@ struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) return NULL; } +static inline +struct rb_node *kvm_memslots_gfn_upper_bound(struct kvm_memslots *slots, gfn_t gfn) +{ + int idx = slots->node_idx; + struct rb_node *node, *result = NULL; + + for (node = slots->gfn_tree.rb_node; node; ) { + struct kvm_memory_slot *slot; + + slot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); + if (gfn < slot->base_gfn) { + result = node; + node = node->rb_left; + } else + node = node->rb_right; + } + + return result; +} + +static inline +struct rb_node *kvm_for_each_in_gfn_first(struct kvm_memslots *slots, gfn_t start) +{ + struct rb_node *node; + + /* + * Find the slot with the lowest gfn that can possibly intersect with + * the range, so we'll ideally have slot start <= range start + */ + node = kvm_memslots_gfn_upper_bound(slots, start); + if (node) { + struct rb_node *pnode; + + /* + * A NULL previous node means that the very first slot + * already has a higher start gfn. + * In this case slot start > range start. + */ + pnode = rb_prev(node); + if (pnode) + node = pnode; + } else { + /* a NULL node below means no slots */ + node = rb_last(&slots->gfn_tree); + } + + return node; +} + +static inline +bool kvm_for_each_in_gfn_no_more(struct kvm_memslots *slots, struct rb_node *node, gfn_t end) +{ + struct kvm_memory_slot *memslot; + + memslot = container_of(node, struct kvm_memory_slot, gfn_node[slots->node_idx]); + + /* + * If this slot starts beyond or at the end of the range so does + * every next one + */ + return memslot->base_gfn >= end; +} + +/* Iterate over each memslot *possibly* intersecting [start, end) range */ +#define kvm_for_each_memslot_in_gfn_range(node, slots, start, end) \ + for (node = kvm_for_each_in_gfn_first(slots, start); \ + node && !kvm_for_each_in_gfn_no_more(slots, node, end); \ + node = rb_next(node)) \ + /* * KVM_SET_USER_MEMORY_REGION ioctl allows the following operations: * - create a new memory slot -- 2.33.1.1089.g2158813163f-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 972ACC433F5 for ; Thu, 4 Nov 2021 00:57:01 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 584DD60F9D for ; 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Wed, 03 Nov 2021 17:26:45 -0700 (PDT) Date: Thu, 4 Nov 2021 00:25:28 +0000 In-Reply-To: <20211104002531.1176691-1-seanjc@google.com> Message-Id: <20211104002531.1176691-28-seanjc@google.com> Mime-Version: 1.0 References: <20211104002531.1176691-1-seanjc@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [PATCH v5.5 27/30] KVM: Optimize gfn lookup in kvm_zap_gfn_range() From: Sean Christopherson To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Atish Patra , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , 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, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Ben Gardon , "Maciej S . Szmigiero" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211103_172647_229380_DBA54631 X-CRM114-Status: GOOD ( 16.29 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Sean Christopherson Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Maciej S. Szmigiero Introduce a memslots gfn upper bound operation and use it to optimize kvm_zap_gfn_range(). This way this handler can do a quick lookup for intersecting gfns and won't have to do a linear scan of the whole memslot set. Signed-off-by: Maciej S. Szmigiero Not-signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 11 +++++-- include/linux/kvm_host.h | 69 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 09ff0ccaa203..14e41278c069 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5714,16 +5714,20 @@ static bool __kvm_zap_rmaps(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) { const struct kvm_memory_slot *memslot; struct kvm_memslots *slots; + struct rb_node *node; bool flush = false; gfn_t start, end; - int i, bkt; + int i, idx; if (!kvm_memslots_have_rmaps(kvm)) return flush; for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, bkt, slots) { + idx = slots->node_idx; + + kvm_for_each_memslot_in_gfn_range(node, slots, gfn_start, gfn_end) { + memslot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); start = max(gfn_start, memslot->base_gfn); end = min(gfn_end, memslot->base_gfn + memslot->npages); if (start >= end) @@ -5747,6 +5751,9 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) bool flush; int i; + if (WARN_ON_ONCE(gfn_end <= gfn_start)) + return; + write_lock(&kvm->mmu_lock); kvm_inc_notifier_count(kvm, gfn_start, gfn_end); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6888f3c2e04b..810a5b958697 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -832,6 +832,75 @@ struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) return NULL; } +static inline +struct rb_node *kvm_memslots_gfn_upper_bound(struct kvm_memslots *slots, gfn_t gfn) +{ + int idx = slots->node_idx; + struct rb_node *node, *result = NULL; + + for (node = slots->gfn_tree.rb_node; node; ) { + struct kvm_memory_slot *slot; + + slot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); + if (gfn < slot->base_gfn) { + result = node; + node = node->rb_left; + } else + node = node->rb_right; + } + + return result; +} + +static inline +struct rb_node *kvm_for_each_in_gfn_first(struct kvm_memslots *slots, gfn_t start) +{ + struct rb_node *node; + + /* + * Find the slot with the lowest gfn that can possibly intersect with + * the range, so we'll ideally have slot start <= range start + */ + node = kvm_memslots_gfn_upper_bound(slots, start); + if (node) { + struct rb_node *pnode; + + /* + * A NULL previous node means that the very first slot + * already has a higher start gfn. + * In this case slot start > range start. + */ + pnode = rb_prev(node); + if (pnode) + node = pnode; + } else { + /* a NULL node below means no slots */ + node = rb_last(&slots->gfn_tree); + } + + return node; +} + +static inline +bool kvm_for_each_in_gfn_no_more(struct kvm_memslots *slots, struct rb_node *node, gfn_t end) +{ + struct kvm_memory_slot *memslot; + + memslot = container_of(node, struct kvm_memory_slot, gfn_node[slots->node_idx]); + + /* + * If this slot starts beyond or at the end of the range so does + * every next one + */ + return memslot->base_gfn >= end; +} + +/* Iterate over each memslot *possibly* intersecting [start, end) range */ +#define kvm_for_each_memslot_in_gfn_range(node, slots, start, end) \ + for (node = kvm_for_each_in_gfn_first(slots, start); \ + node && !kvm_for_each_in_gfn_no_more(slots, node, end); \ + node = rb_next(node)) \ + /* * KVM_SET_USER_MEMORY_REGION ioctl allows the following operations: * - create a new memory slot -- 2.33.1.1089.g2158813163f-goog _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51E03C433F5 for ; Thu, 4 Nov 2021 00:56:22 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 18FB060EB9 for ; 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Wed, 03 Nov 2021 17:26:45 -0700 (PDT) Date: Thu, 4 Nov 2021 00:25:28 +0000 In-Reply-To: <20211104002531.1176691-1-seanjc@google.com> Message-Id: <20211104002531.1176691-28-seanjc@google.com> Mime-Version: 1.0 References: <20211104002531.1176691-1-seanjc@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [PATCH v5.5 27/30] KVM: Optimize gfn lookup in kvm_zap_gfn_range() From: Sean Christopherson To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Atish Patra , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , 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, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Ben Gardon , "Maciej S . Szmigiero" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211103_172646_662757_E7C0D8A5 X-CRM114-Status: GOOD ( 17.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Sean Christopherson Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Maciej S. Szmigiero Introduce a memslots gfn upper bound operation and use it to optimize kvm_zap_gfn_range(). This way this handler can do a quick lookup for intersecting gfns and won't have to do a linear scan of the whole memslot set. Signed-off-by: Maciej S. Szmigiero Not-signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 11 +++++-- include/linux/kvm_host.h | 69 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 09ff0ccaa203..14e41278c069 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5714,16 +5714,20 @@ static bool __kvm_zap_rmaps(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) { const struct kvm_memory_slot *memslot; struct kvm_memslots *slots; + struct rb_node *node; bool flush = false; gfn_t start, end; - int i, bkt; + int i, idx; if (!kvm_memslots_have_rmaps(kvm)) return flush; for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, bkt, slots) { + idx = slots->node_idx; + + kvm_for_each_memslot_in_gfn_range(node, slots, gfn_start, gfn_end) { + memslot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); start = max(gfn_start, memslot->base_gfn); end = min(gfn_end, memslot->base_gfn + memslot->npages); if (start >= end) @@ -5747,6 +5751,9 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) bool flush; int i; + if (WARN_ON_ONCE(gfn_end <= gfn_start)) + return; + write_lock(&kvm->mmu_lock); kvm_inc_notifier_count(kvm, gfn_start, gfn_end); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6888f3c2e04b..810a5b958697 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -832,6 +832,75 @@ struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) return NULL; } +static inline +struct rb_node *kvm_memslots_gfn_upper_bound(struct kvm_memslots *slots, gfn_t gfn) +{ + int idx = slots->node_idx; + struct rb_node *node, *result = NULL; + + for (node = slots->gfn_tree.rb_node; node; ) { + struct kvm_memory_slot *slot; + + slot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); + if (gfn < slot->base_gfn) { + result = node; + node = node->rb_left; + } else + node = node->rb_right; + } + + return result; +} + +static inline +struct rb_node *kvm_for_each_in_gfn_first(struct kvm_memslots *slots, gfn_t start) +{ + struct rb_node *node; + + /* + * Find the slot with the lowest gfn that can possibly intersect with + * the range, so we'll ideally have slot start <= range start + */ + node = kvm_memslots_gfn_upper_bound(slots, start); + if (node) { + struct rb_node *pnode; + + /* + * A NULL previous node means that the very first slot + * already has a higher start gfn. + * In this case slot start > range start. + */ + pnode = rb_prev(node); + if (pnode) + node = pnode; + } else { + /* a NULL node below means no slots */ + node = rb_last(&slots->gfn_tree); + } + + return node; +} + +static inline +bool kvm_for_each_in_gfn_no_more(struct kvm_memslots *slots, struct rb_node *node, gfn_t end) +{ + struct kvm_memory_slot *memslot; + + memslot = container_of(node, struct kvm_memory_slot, gfn_node[slots->node_idx]); + + /* + * If this slot starts beyond or at the end of the range so does + * every next one + */ + return memslot->base_gfn >= end; +} + +/* Iterate over each memslot *possibly* intersecting [start, end) range */ +#define kvm_for_each_memslot_in_gfn_range(node, slots, start, end) \ + for (node = kvm_for_each_in_gfn_first(slots, start); \ + node && !kvm_for_each_in_gfn_no_more(slots, node, end); \ + node = rb_next(node)) \ + /* * KVM_SET_USER_MEMORY_REGION ioctl allows the following operations: * - create a new memory slot -- 2.33.1.1089.g2158813163f-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sean Christopherson Date: Thu, 04 Nov 2021 00:25:28 +0000 Subject: [PATCH v5.5 27/30] KVM: Optimize gfn lookup in kvm_zap_gfn_range() Message-Id: <20211104002531.1176691-28-seanjc@google.com> List-Id: References: <20211104002531.1176691-1-seanjc@google.com> In-Reply-To: <20211104002531.1176691-1-seanjc@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Atish Patra , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , 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, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Ben Gardon , "Maciej S . Szmigiero" From: Maciej S. Szmigiero Introduce a memslots gfn upper bound operation and use it to optimize kvm_zap_gfn_range(). This way this handler can do a quick lookup for intersecting gfns and won't have to do a linear scan of the whole memslot set. Signed-off-by: Maciej S. Szmigiero Not-signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 11 +++++-- include/linux/kvm_host.h | 69 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 09ff0ccaa203..14e41278c069 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5714,16 +5714,20 @@ static bool __kvm_zap_rmaps(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) { const struct kvm_memory_slot *memslot; struct kvm_memslots *slots; + struct rb_node *node; bool flush = false; gfn_t start, end; - int i, bkt; + int i, idx; if (!kvm_memslots_have_rmaps(kvm)) return flush; for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, bkt, slots) { + idx = slots->node_idx; + + kvm_for_each_memslot_in_gfn_range(node, slots, gfn_start, gfn_end) { + memslot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); start = max(gfn_start, memslot->base_gfn); end = min(gfn_end, memslot->base_gfn + memslot->npages); if (start >= end) @@ -5747,6 +5751,9 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) bool flush; int i; + if (WARN_ON_ONCE(gfn_end <= gfn_start)) + return; + write_lock(&kvm->mmu_lock); kvm_inc_notifier_count(kvm, gfn_start, gfn_end); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6888f3c2e04b..810a5b958697 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -832,6 +832,75 @@ struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) return NULL; } +static inline +struct rb_node *kvm_memslots_gfn_upper_bound(struct kvm_memslots *slots, gfn_t gfn) +{ + int idx = slots->node_idx; + struct rb_node *node, *result = NULL; + + for (node = slots->gfn_tree.rb_node; node; ) { + struct kvm_memory_slot *slot; + + slot = container_of(node, struct kvm_memory_slot, gfn_node[idx]); + if (gfn < slot->base_gfn) { + result = node; + node = node->rb_left; + } else + node = node->rb_right; + } + + return result; +} + +static inline +struct rb_node *kvm_for_each_in_gfn_first(struct kvm_memslots *slots, gfn_t start) +{ + struct rb_node *node; + + /* + * Find the slot with the lowest gfn that can possibly intersect with + * the range, so we'll ideally have slot start <= range start + */ + node = kvm_memslots_gfn_upper_bound(slots, start); + if (node) { + struct rb_node *pnode; + + /* + * A NULL previous node means that the very first slot + * already has a higher start gfn. + * In this case slot start > range start. + */ + pnode = rb_prev(node); + if (pnode) + node = pnode; + } else { + /* a NULL node below means no slots */ + node = rb_last(&slots->gfn_tree); + } + + return node; +} + +static inline +bool kvm_for_each_in_gfn_no_more(struct kvm_memslots *slots, struct rb_node *node, gfn_t end) +{ + struct kvm_memory_slot *memslot; + + memslot = container_of(node, struct kvm_memory_slot, gfn_node[slots->node_idx]); + + /* + * If this slot starts beyond or at the end of the range so does + * every next one + */ + return memslot->base_gfn >= end; +} + +/* Iterate over each memslot *possibly* intersecting [start, end) range */ +#define kvm_for_each_memslot_in_gfn_range(node, slots, start, end) \ + for (node = kvm_for_each_in_gfn_first(slots, start); \ + node && !kvm_for_each_in_gfn_no_more(slots, node, end); \ + node = rb_next(node)) \ + /* * KVM_SET_USER_MEMORY_REGION ioctl allows the following operations: * - create a new memory slot -- 2.33.1.1089.g2158813163f-goog