Received: by 2002:a05:6a10:206:0:0:0:0 with SMTP id 6csp2179622pxj; Sun, 16 May 2021 17:32:58 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyONnXMsTF+t+hHKKyDruvbBnQRxhu9l5kCETIBVbW6W+i7XuqZ4shViU+zu2Qg0qnwtUlI X-Received: by 2002:a92:c884:: with SMTP id w4mr49902485ilo.186.1621211578780; Sun, 16 May 2021 17:32:58 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1621211578; cv=none; d=google.com; s=arc-20160816; b=NnRTQXT8whnCbkJ/ed0HHjoZKIF5c5WNeC6Hr2ovlKmfHjuEyifvPQXq4CiT2oXnSx Rxfo0lYlcp88CfHvEnmB9prBlCaRTwbozp45FH0dY+qKQj0YBZYzza2nfh0aXBlImVuY Hi0sI4KRXvOEQ7bkN43jETZbVExp0uo7tVIfgexPgPD3nPzhli84k3UB8CHQxweXcUtB YCuXRDxeBUx1PZsz63FN36t9/l5VxK0eVUYVUmb7/lW4ugypsbnDpuvcTdNIA1SVI5xD HKEjTh8vlnxX+punQwkaH4yDxVP+XMzd4a1vJpArb15EryENR5ETINbE6QM6fPvkNVSQ mu/Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=+1usIs9Tk0iFyAnctT0LWFeDsqKrECu9f6/w0PKHDmk=; b=o/PpCQ6o/MYKNicyetQvjZlQgbmszX5R/pouVHxdOadbR5odSicFZs2LOmjoyFRRsh xEErkQ2Fnjoz+jlgbOQiFP0oulqZp6xYH+sHezM1B7a0cH2zxR8vW7yP1aB7J+0sGVeJ RDaAsxUAhyivH+yATnuMjkfWxZZ6UQcXAhs1IlkjkkM6VwSZ1PI5UEghH2KpMXSzHNOh Po35K+/hPLn7Xpg+1rwSH4+wFOSRC6FxLfyXA7rPgl+d4Z/BZ3Eeu03jjBocFApyUs9X Rt8L7vQVue4vzpDW+xOGjqI7MsBWJEAf2qGD3WNhqdZNzAw6BsKJHClqCrS+pAn7dcLx bZ4Q== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id y5si8189113ilu.66.2021.05.16.17.32.46; Sun, 16 May 2021 17:32:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234483AbhEPVqo (ORCPT + 99 others); Sun, 16 May 2021 17:46:44 -0400 Received: from vps-vb.mhejs.net ([37.28.154.113]:54438 "EHLO vps-vb.mhejs.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234389AbhEPVqi (ORCPT ); Sun, 16 May 2021 17:46:38 -0400 Received: from MUA by vps-vb.mhejs.net with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1liOZJ-0007zY-KN; Sun, 16 May 2021 23:45:01 +0200 From: "Maciej S. Szmigiero" To: Paolo Bonzini , Vitaly Kuznetsov Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Igor Mammedov , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Christian Borntraeger , Janosch Frank , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 4/8] KVM: Introduce memslots hva tree Date: Sun, 16 May 2021 23:44:30 +0200 Message-Id: X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Maciej S. Szmigiero" The current memslots implementation only allows quick binary search by gfn, quick lookup by hva is not possible - the implementation has to do a linear scan of the whole memslots array, even though the operation being performed might apply just to a single memslot. This significantly hurts performance of per-hva operations with higher memslot counts. Since hva ranges can overlap between memslots an interval tree is needed for tracking them. Signed-off-by: Maciej S. Szmigiero --- arch/arm64/kvm/Kconfig | 1 + arch/mips/kvm/Kconfig | 1 + arch/powerpc/kvm/Kconfig | 1 + arch/s390/kvm/Kconfig | 1 + arch/x86/kvm/Kconfig | 1 + include/linux/kvm_host.h | 8 ++++++++ virt/kvm/kvm_main.c | 43 +++++++++++++++++++++++++++++++++------- 7 files changed, 49 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 3964acf5451e..f075e9939a2a 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -40,6 +40,7 @@ menuconfig KVM select HAVE_KVM_VCPU_RUN_PID_CHANGE select TASKSTATS select TASK_DELAY_ACCT + select INTERVAL_TREE help Support hosting virtualized guest machines. diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig index a77297480f56..91d197bee9c0 100644 --- a/arch/mips/kvm/Kconfig +++ b/arch/mips/kvm/Kconfig @@ -27,6 +27,7 @@ config KVM select KVM_MMIO select MMU_NOTIFIER select SRCU + select INTERVAL_TREE help Support for hosting Guest kernels. diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig index e45644657d49..519d6d3642a5 100644 --- a/arch/powerpc/kvm/Kconfig +++ b/arch/powerpc/kvm/Kconfig @@ -26,6 +26,7 @@ config KVM select KVM_VFIO select IRQ_BYPASS_MANAGER select HAVE_KVM_IRQ_BYPASS + select INTERVAL_TREE config KVM_BOOK3S_HANDLER bool diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig index 67a8e770e369..2e84d3922f7c 100644 --- a/arch/s390/kvm/Kconfig +++ b/arch/s390/kvm/Kconfig @@ -33,6 +33,7 @@ config KVM select HAVE_KVM_NO_POLL select SRCU select KVM_VFIO + select INTERVAL_TREE help Support hosting paravirtualized guest machines using the SIE virtualization capability on the mainframe. This should work diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index f6b93a35ce14..ee15f7e113c8 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -46,6 +46,7 @@ config KVM select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_VFIO select SRCU + select INTERVAL_TREE help Support hosting fully virtualized guest machines using hardware virtualization extensions. You will need a fairly recent diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index d3a35646dfd8..f59847b6e9b3 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -358,6 +359,7 @@ static inline int kvm_vcpu_exiting_guest_mode(struct kvm_vcpu *vcpu) struct kvm_memory_slot { struct hlist_node id_node; + struct interval_tree_node hva_node; gfn_t base_gfn; unsigned long npages; unsigned long *dirty_bitmap; @@ -459,6 +461,7 @@ static inline int kvm_arch_vcpu_memslots_id(struct kvm_vcpu *vcpu) */ struct kvm_memslots { u64 generation; + struct rb_root_cached hva_tree; /* The mapping table from slot id to the index in memslots[]. */ DECLARE_HASHTABLE(id_hash, 7); atomic_t lru_slot; @@ -679,6 +682,11 @@ static inline struct kvm_memslots *kvm_vcpu_memslots(struct kvm_vcpu *vcpu) return __kvm_memslots(vcpu->kvm, as_id); } +#define kvm_for_each_hva_range_memslot(node, slots, start, last) \ + for (node = interval_tree_iter_first(&slots->hva_tree, start, last); \ + node; \ + node = interval_tree_iter_next(node, start, last)) \ + static inline struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) { diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 50f9bc9bb1e0..a55309432c9a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -488,6 +488,9 @@ static __always_inline int __kvm_handle_hva_range(struct kvm *kvm, struct kvm_memslots *slots; int i, idx; + if (range->end == range->start || WARN_ON(range->end < range->start)) + return 0; + /* A null handler is allowed if and only if on_lock() is provided. */ if (WARN_ON_ONCE(IS_KVM_NULL_FN(range->on_lock) && IS_KVM_NULL_FN(range->handler))) @@ -507,15 +510,18 @@ static __always_inline int __kvm_handle_hva_range(struct kvm *kvm, } for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { + struct interval_tree_node *node; + slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(slot, slots) { + kvm_for_each_hva_range_memslot(node, slots, + range->start, range->end - 1) { unsigned long hva_start, hva_end; + slot = container_of(node, struct kvm_memory_slot, + hva_node); hva_start = max(range->start, slot->userspace_addr); hva_end = min(range->end, slot->userspace_addr + (slot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; /* * To optimize for the likely case where the address @@ -787,6 +793,7 @@ static struct kvm_memslots *kvm_alloc_memslots(void) if (!slots) return NULL; + slots->hva_tree = RB_ROOT_CACHED; hash_init(slots->id_hash); return slots; @@ -1113,10 +1120,14 @@ static inline void kvm_memslot_delete(struct kvm_memslots *slots, atomic_set(&slots->lru_slot, 0); for (i = dmemslot - mslots; i < slots->used_slots; i++) { + interval_tree_remove(&mslots[i].hva_node, &slots->hva_tree); hash_del(&mslots[i].id_node); + mslots[i] = mslots[i + 1]; + interval_tree_insert(&mslots[i].hva_node, &slots->hva_tree); hash_add(slots->id_hash, &mslots[i].id_node, mslots[i].id); } + interval_tree_remove(&mslots[i].hva_node, &slots->hva_tree); hash_del(&mslots[i].id_node); mslots[i] = *memslot; } @@ -1136,7 +1147,8 @@ static inline int kvm_memslot_insert_back(struct kvm_memslots *slots) * itself is not preserved in the array, i.e. not swapped at this time, only * its new index into the array is tracked. Returns the changed memslot's * current index into the memslots array. - * The memslot at the returned index will not be in @slots->id_hash by then. + * The memslot at the returned index will not be in @slots->hva_tree or + * @slots->id_hash by then. * @memslot is a detached struct with desired final data of the changed slot. */ static inline int kvm_memslot_move_backward(struct kvm_memslots *slots, @@ -1154,6 +1166,7 @@ static inline int kvm_memslot_move_backward(struct kvm_memslots *slots, * update_memslots() will unconditionally overwrite and re-add the * target memslot so it has to be removed here first */ + interval_tree_remove(&mmemslot->hva_node, &slots->hva_tree); hash_del(&mmemslot->id_node); /* @@ -1168,8 +1181,11 @@ static inline int kvm_memslot_move_backward(struct kvm_memslots *slots, WARN_ON_ONCE(memslot->base_gfn == mslots[i + 1].base_gfn); /* Shift the next memslot forward one and update its index. */ + interval_tree_remove(&mslots[i + 1].hva_node, &slots->hva_tree); hash_del(&mslots[i + 1].id_node); + mslots[i] = mslots[i + 1]; + interval_tree_insert(&mslots[i].hva_node, &slots->hva_tree); hash_add(slots->id_hash, &mslots[i].id_node, mslots[i].id); } return i; @@ -1181,10 +1197,12 @@ static inline int kvm_memslot_move_backward(struct kvm_memslots *slots, * is not preserved in the array, i.e. not swapped at this time, only its new * index into the array is tracked. Returns the changed memslot's final index * into the memslots array. - * The memslot at the returned index will not be in @slots->id_hash by then. + * The memslot at the returned index will not be in @slots->hva_tree or + * @slots->id_hash by then. * @memslot is a detached struct with desired final data of the new or * changed slot. - * Assumes that the memslot at @start index is not in @slots->id_hash. + * Assumes that the memslot at @start index is not in @slots->hva_tree or + * @slots->id_hash. */ static inline int kvm_memslot_move_forward(struct kvm_memslots *slots, struct kvm_memory_slot *memslot, @@ -1200,8 +1218,11 @@ static inline int kvm_memslot_move_forward(struct kvm_memslots *slots, WARN_ON_ONCE(memslot->base_gfn == mslots[i - 1].base_gfn); /* Shift the next memslot back one and update its index. */ + interval_tree_remove(&mslots[i - 1].hva_node, &slots->hva_tree); hash_del(&mslots[i - 1].id_node); + mslots[i] = mslots[i - 1]; + interval_tree_insert(&mslots[i].hva_node, &slots->hva_tree); hash_add(slots->id_hash, &mslots[i].id_node, mslots[i].id); } return i; @@ -1274,6 +1295,11 @@ static void update_memslots(struct kvm_memslots *slots, * its index accordingly. */ slots->memslots[i] = *memslot; + slots->memslots[i].hva_node.start = memslot->userspace_addr; + slots->memslots[i].hva_node.last = memslot->userspace_addr + + (memslot->npages << PAGE_SHIFT) - 1; + interval_tree_insert(&slots->memslots[i].hva_node, + &slots->hva_tree); hash_add(slots->id_hash, &slots->memslots[i].id_node, memslot->id); } @@ -1355,9 +1381,12 @@ static struct kvm_memslots *kvm_dup_memslots(struct kvm_memslots *old, memcpy(slots, old, old_size); + slots->hva_tree = RB_ROOT_CACHED; hash_init(slots->id_hash); - kvm_for_each_memslot(memslot, slots) + kvm_for_each_memslot(memslot, slots) { + interval_tree_insert(&memslot->hva_node, &slots->hva_tree); hash_add(slots->id_hash, &memslot->id_node, memslot->id); + } return slots; }