From patchwork Tue Apr 13 14:10:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Maciej S. Szmigiero" X-Patchwork-Id: 12200737 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 B377CC433ED for ; Tue, 13 Apr 2021 14:33:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D1C06135C for ; Tue, 13 Apr 2021 14:33:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245612AbhDMOdt (ORCPT ); Tue, 13 Apr 2021 10:33:49 -0400 Received: from vps-vb.mhejs.net ([37.28.154.113]:49720 "EHLO vps-vb.mhejs.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245740AbhDMOdc (ORCPT ); Tue, 13 Apr 2021 10:33:32 -0400 Received: from MUA by vps-vb.mhejs.net with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.93.0.4) (envelope-from ) id 1lWJkX-0003zd-7K; Tue, 13 Apr 2021 16:10:41 +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 v2 4/8] KVM: Introduce memslots hva tree Date: Tue, 13 Apr 2021 16:10:10 +0200 Message-Id: <03be687278c659220d5e354eb980bbf59dc8faa0.1618322003.git.maciej.szmigiero@oracle.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@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/arm64/kvm/mmu.c | 10 +++++++--- arch/mips/kvm/Kconfig | 1 + arch/mips/kvm/mmu.c | 10 +++++++--- arch/powerpc/kvm/Kconfig | 1 + arch/powerpc/kvm/book3s_64_mmu_hv.c | 10 +++++++--- arch/powerpc/kvm/book3s_pr.c | 10 +++++++--- arch/s390/kvm/Kconfig | 1 + arch/x86/kvm/Kconfig | 1 + arch/x86/kvm/mmu/mmu.c | 11 +++++++--- arch/x86/kvm/mmu/tdp_mmu.c | 13 +++++++++--- include/linux/kvm_host.h | 8 ++++++++ virt/kvm/kvm_main.c | 31 +++++++++++++++++++++++++---- 13 files changed, 86 insertions(+), 22 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/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 4b7e1e327337..4b0ac98a5a53 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1073,21 +1073,25 @@ static int handle_hva_to_gpa(struct kvm *kvm, void *data) { struct kvm_memslots *slots; + struct interval_tree_node *node; struct kvm_memory_slot *memslot; int ret = 0; + if (end == start || WARN_ON(end < start)) + return 0; + slots = kvm_memslots(kvm); /* we only care about the pages that the guest sees */ - kvm_for_each_memslot(memslot, slots) { + kvm_for_each_hva_range_memslot(node, slots, start, end - 1) { unsigned long hva_start, hva_end; gfn_t gpa; + memslot = container_of(node, struct kvm_memory_slot, + hva_node); hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; gpa = hva_to_gfn_memslot(hva_start, memslot) << PAGE_SHIFT; ret |= handler(kvm, gpa, (u64)(hva_end - hva_start), data); diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig index 032b3fca6cbb..5ba260f38e75 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/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c index 3dabeda82458..0c7c48f08ec2 100644 --- a/arch/mips/kvm/mmu.c +++ b/arch/mips/kvm/mmu.c @@ -449,21 +449,25 @@ static int handle_hva_to_gpa(struct kvm *kvm, void *data) { struct kvm_memslots *slots; + struct interval_tree_node *node; struct kvm_memory_slot *memslot; int ret = 0; + if (end == start || WARN_ON(end < start)) + return 0; + slots = kvm_memslots(kvm); /* we only care about the pages that the guest sees */ - kvm_for_each_memslot(memslot, slots) { + kvm_for_each_hva_range_memslot(node, slots, start, end - 1) { unsigned long hva_start, hva_end; gfn_t gfn, gfn_end; + memslot = container_of(node, struct kvm_memory_slot, + hva_node); hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; /* * {gfn(page) | page intersects with [hva_start, hva_end)} = 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/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index bb6773594cf8..fca2a978617c 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -763,18 +763,22 @@ static int kvm_handle_hva_range(struct kvm *kvm, int ret; int retval = 0; struct kvm_memslots *slots; + struct interval_tree_node *node; struct kvm_memory_slot *memslot; + if (end == start || WARN_ON(end < start)) + return 0; + slots = kvm_memslots(kvm); - kvm_for_each_memslot(memslot, slots) { + kvm_for_each_hva_range_memslot(node, slots, start, end - 1) { unsigned long hva_start, hva_end; gfn_t gfn, gfn_end; + memslot = container_of(node, struct kvm_memory_slot, + hva_node); hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; /* * {gfn(page) | page intersects with [hva_start, hva_end)} = * {gfn, gfn+1, ..., gfn_end-1}. diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 913944dc3620..d0a7127403f0 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -431,18 +431,22 @@ static void do_kvm_unmap_hva(struct kvm *kvm, unsigned long start, long i; struct kvm_vcpu *vcpu; struct kvm_memslots *slots; + struct interval_tree_node *node; struct kvm_memory_slot *memslot; + if (end == start || WARN_ON(end < start)) + return; + slots = kvm_memslots(kvm); - kvm_for_each_memslot(memslot, slots) { + kvm_for_each_hva_range_memslot(node, slots, start, end - 1) { unsigned long hva_start, hva_end; gfn_t gfn, gfn_end; + memslot = container_of(node, struct kvm_memory_slot, + hva_node); hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; /* * {gfn(page) | page intersects with [hva_start, hva_end)} = * {gfn, gfn+1, ..., gfn_end-1}. 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 a788d5120d4d..59225775e4f5 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/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 762314b04a39..75fa497aa27f 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1430,17 +1430,22 @@ static __always_inline int kvm_handle_hva_range(struct kvm *kvm, int ret = 0; int i; + if (end == start || WARN_ON(end < start)) + return 0; + for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { + struct interval_tree_node *node; + slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, slots) { + kvm_for_each_hva_range_memslot(node, slots, start, end - 1) { unsigned long hva_start, hva_end; gfn_t gfn_start, gfn_end; + memslot = container_of(node, struct kvm_memory_slot, + hva_node); hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; /* * {gfn(page) | page intersects with [hva_start, hva_end)} = * {gfn_start, gfn_start+1, ..., gfn_end-1}. diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index ccf0d774a181..69683028763c 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -889,18 +889,25 @@ static __always_inline int kvm_tdp_mmu_handle_hva_range(struct kvm *kvm, int ret = 0; int as_id; + if (end == start || WARN_ON(end < start)) + return 0; + for (as_id = 0; as_id < KVM_ADDRESS_SPACE_NUM; as_id++) { for_each_tdp_mmu_root_yield_safe(kvm, root, as_id) { + struct interval_tree_node *node; + slots = __kvm_memslots(kvm, as_id); - kvm_for_each_memslot(memslot, slots) { + kvm_for_each_hva_range_memslot(node, slots, + start, end - 1) { unsigned long hva_start, hva_end; gfn_t gfn_start, gfn_end; + memslot = container_of(node, + struct kvm_memory_slot, + hva_node); hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); - if (hva_start >= hva_end) - continue; /* * {gfn(page) | page intersects with [hva_start, hva_end)} = * {gfn_start, gfn_start+1, ..., gfn_end-1}. diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index e4aadb9875e9..b8196cbd2c6f 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -352,6 +353,7 @@ 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; @@ -453,6 +455,7 @@ 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; @@ -673,6 +676,11 @@ 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 8f0b49d937d1..37b44cde9ae7 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -662,6 +662,7 @@ 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; @@ -988,10 +989,14 @@ 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; } @@ -1011,7 +1016,8 @@ 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, @@ -1029,6 +1035,7 @@ 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); /* @@ -1043,8 +1050,11 @@ 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; @@ -1056,10 +1066,12 @@ 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, @@ -1075,8 +1087,11 @@ 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; @@ -1149,6 +1164,11 @@ 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); } @@ -1230,9 +1250,12 @@ 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; }