From patchwork Fri May 6 20:53:58 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= X-Patchwork-Id: 9036101 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 92E299F372 for ; Fri, 6 May 2016 20:54:31 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 925C120172 for ; Fri, 6 May 2016 20:54:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 610AD202FF for ; Fri, 6 May 2016 20:54:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758604AbcEFUy0 (ORCPT ); Fri, 6 May 2016 16:54:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58229 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758275AbcEFUyZ (ORCPT ); Fri, 6 May 2016 16:54:25 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A1EA7C01AA41; Fri, 6 May 2016 20:54:24 +0000 (UTC) Received: from potion (dhcp-1-215.brq.redhat.com [10.34.1.215]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with SMTP id u46KsLgn011203; Fri, 6 May 2016 16:54:22 -0400 Received: by potion (sSMTP sendmail emulation); Fri, 06 May 2016 22:54:21 +0200 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= To: kvm@vger.kernel.org Cc: Paolo Bonzini , "Lan, Tianyu" , Igor Mammedov , Jan Kiszka , Peter Xu Subject: [PATCH 2/9] KVM: x86: dynamic kvm_apic_map Date: Fri, 6 May 2016 22:53:58 +0200 Message-Id: <1462568045-31085-3-git-send-email-rkrcmar@redhat.com> In-Reply-To: <1462568045-31085-1-git-send-email-rkrcmar@redhat.com> References: <1462568045-31085-1-git-send-email-rkrcmar@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-9.0 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP x2APIC supports up to 2^32-1 LAPICs, but most guest in coming years will have slighly less VCPUs. Dynamic size saves memory at the cost of turning one constant into a variable. apic_map mutex had to be moved before allocation to avoid races with cpu hotplug. Signed-off-by: Radim Kr?má? --- arch/x86/include/asm/kvm_host.h | 9 +++-- arch/x86/kvm/lapic.c | 87 ++++++++++++++++++++++------------------- arch/x86/kvm/lapic.h | 2 +- 3 files changed, 54 insertions(+), 44 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index b7e394485a5f..c93c4a7877ed 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -682,9 +682,12 @@ struct kvm_arch_memory_slot { struct kvm_apic_map { struct rcu_head rcu; u8 mode; - struct kvm_lapic *phys_map[256]; - /* first index is cluster id second is cpu id in a cluster */ - struct kvm_lapic *logical_map[16][16]; + u32 size; + union { + struct kvm_lapic *xapic_flat_map[8]; + struct kvm_lapic *xapic_cluster_map[16][4]; + }; + struct kvm_lapic *phys_map[]; }; /* Hyper-V emulation context */ diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 6812e61c12d4..90e07c109dfe 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -129,26 +129,32 @@ static inline int apic_enabled(struct kvm_lapic *apic) (LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \ APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER) -/* The logical map is definitely wrong if we have multiple - * modes at the same time. (Physical map is always right.) - */ -static inline bool kvm_apic_logical_map_valid(struct kvm_apic_map *map) -{ - return !(map->mode & (map->mode - 1)); -} +static inline bool kvm_apic_map_get_logical_dest(struct kvm_apic_map *map, + u32 dest_id, struct kvm_lapic ***cluster, u16 *mask) { + switch (map->mode) { + case KVM_APIC_MODE_X2APIC: { + u32 offset = (dest_id >> 16) * 16; + // XXX: phys_map must be allocated as multiples of 16 + if (offset < map->size) { + *cluster = &map->phys_map[offset]; + *mask = dest_id & 0xffff; + } else + *mask = 0; -static inline void -apic_logical_id(struct kvm_apic_map *map, u32 dest_id, u16 *cid, u16 *lid) -{ - unsigned lid_bits; - - BUILD_BUG_ON(KVM_APIC_MODE_XAPIC_CLUSTER != 4); - BUILD_BUG_ON(KVM_APIC_MODE_XAPIC_FLAT != 8); - BUILD_BUG_ON(KVM_APIC_MODE_X2APIC != 16); - lid_bits = map->mode; - - *cid = dest_id >> lid_bits; - *lid = dest_id & ((1 << lid_bits) - 1); + return true; + } + case KVM_APIC_MODE_XAPIC_FLAT: + *cluster = map->xapic_flat_map; + *mask = dest_id & 0xff; + return true; + case KVM_APIC_MODE_XAPIC_CLUSTER: + *cluster = map->xapic_cluster_map[dest_id >> 4]; + *mask = dest_id & 0xf; + return true; + default: + /* Not optimized. */ + return false; + } } static void recalculate_apic_map(struct kvm *kvm) @@ -156,17 +162,28 @@ static void recalculate_apic_map(struct kvm *kvm) struct kvm_apic_map *new, *old = NULL; struct kvm_vcpu *vcpu; int i; - - new = kzalloc(sizeof(struct kvm_apic_map), GFP_KERNEL); + u32 size = 255; mutex_lock(&kvm->arch.apic_map_lock); + kvm_for_each_vcpu(i, vcpu, kvm) + if (kvm_apic_present(vcpu)) + size = max(size, kvm_apic_id(vcpu->arch.apic)); + + size++; + size += (16 - size) & 16; + new = kzalloc(sizeof(struct kvm_apic_map) + + sizeof(struct kvm_lapic) * size, GFP_KERNEL); + if (!new) goto out; + new->size = size; + kvm_for_each_vcpu(i, vcpu, kvm) { struct kvm_lapic *apic = vcpu->arch.apic; - u16 cid, lid; + struct kvm_lapic **cluster; + u16 mask; u32 ldr, aid; if (!kvm_apic_present(vcpu)) @@ -175,7 +192,7 @@ static void recalculate_apic_map(struct kvm *kvm) aid = kvm_apic_id(apic); ldr = kvm_apic_get_reg(apic, APIC_LDR); - if (aid < ARRAY_SIZE(new->phys_map)) + if (aid < size) new->phys_map[aid] = apic; if (apic_x2apic_mode(apic)) { @@ -188,13 +205,11 @@ static void recalculate_apic_map(struct kvm *kvm) new->mode |= KVM_APIC_MODE_XAPIC_CLUSTER; } - if (!kvm_apic_logical_map_valid(new)) + if (!kvm_apic_map_get_logical_dest(new, ldr, &cluster, &mask)) continue; - apic_logical_id(new, ldr, &cid, &lid); - - if (lid && cid < ARRAY_SIZE(new->logical_map)) - new->logical_map[cid][ffs(lid) - 1] = apic; + if (mask) + cluster[ffs(mask) - 1] = apic; } out: old = rcu_dereference_protected(kvm->arch.apic_map, @@ -703,7 +718,6 @@ static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm, struct kvm_lapic { int i, lowest; bool x2apic_ipi; - u16 cid; if (irq->shorthand == APIC_DEST_SELF) { *dst = &src; @@ -720,7 +734,7 @@ static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm, struct kvm_lapic return false; if (irq->dest_mode == APIC_DEST_PHYSICAL) { - if (irq->dest_id >= ARRAY_SIZE(map->phys_map)) { + if (irq->dest_id >= map->size) { *bitmap = 0; } else { *dst = &map->phys_map[irq->dest_id]; @@ -729,18 +743,11 @@ static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm, struct kvm_lapic return true; } - if (!kvm_apic_logical_map_valid(map)) + *bitmap = 0; + if (!kvm_apic_map_get_logical_dest(map, irq->dest_id, dst, + (u16 *)bitmap)) return false; - apic_logical_id(map, irq->dest_id, &cid, (u16 *)bitmap); - - if (cid >= ARRAY_SIZE(map->logical_map)) { - *bitmap = 0; - return true; - } - - *dst = map->logical_map[cid]; - if (!kvm_lowest_prio_delivery(irq)) return true; diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h index f71183e502ee..d818a36ce24e 100644 --- a/arch/x86/kvm/lapic.h +++ b/arch/x86/kvm/lapic.h @@ -167,7 +167,7 @@ static inline int kvm_lapic_latched_init(struct kvm_vcpu *vcpu) return lapic_in_kernel(vcpu) && test_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events); } -static inline int kvm_apic_id(struct kvm_lapic *apic) +static inline u32 kvm_apic_id(struct kvm_lapic *apic) { return (kvm_apic_get_reg(apic, APIC_ID) >> 24) & 0xff; }