From patchwork Fri May 6 20:53:57 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: 9036091 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 C7BDA9F372 for ; Fri, 6 May 2016 20:54:28 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BB1E720172 for ; Fri, 6 May 2016 20:54:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5AA420219 for ; Fri, 6 May 2016 20:54:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758579AbcEFUyW (ORCPT ); Fri, 6 May 2016 16:54:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41858 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758503AbcEFUyV (ORCPT ); Fri, 6 May 2016 16:54:21 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (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 680487F0A3; Fri, 6 May 2016 20:54:21 +0000 (UTC) Received: from potion (dhcp-1-215.brq.redhat.com [10.34.1.215]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with SMTP id u46KsIv4026007; Fri, 6 May 2016 16:54:19 -0400 Received: by potion (sSMTP sendmail emulation); Fri, 06 May 2016 22:54:18 +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 1/9] KVM: x86: add kvm_apic_map_get_dest_lapic Date: Fri, 6 May 2016 22:53:57 +0200 Message-Id: <1462568045-31085-2-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 10.5.11.22 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 kvm_irq_delivery_to_apic_fast and kvm_intr_is_single_vcpu_fast both compute the interrupt destination. Factor the code. 'struct kvm_lapic **dst = NULL' had to be added to silence GCC. GCC might complain about potential NULL access in the future, because it missed conditions that avoided uninitialized uses of dst. Signed-off-by: Radim Kr?má? --- arch/x86/kvm/lapic.c | 237 +++++++++++++++++++++------------------------------ 1 file changed, 99 insertions(+), 138 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 1a2da0e5a373..6812e61c12d4 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -694,14 +694,94 @@ static void kvm_apic_disabled_lapic_found(struct kvm *kvm) } } +/* If kvm_apic_map_get_dest_lapic returns true, then *bitmap encodes accessible + * elements in the *dst array. Those are destinations for the interrupt. + */ +static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm, struct kvm_lapic *src, + struct kvm_lapic_irq *irq, struct kvm_apic_map *map, + struct kvm_lapic ***dst, unsigned long *bitmap) +{ + int i, lowest; + bool x2apic_ipi; + u16 cid; + + if (irq->shorthand == APIC_DEST_SELF) { + *dst = &src; + *bitmap = 1; + return true; + } else if (irq->shorthand) + return false; + + x2apic_ipi = src && apic_x2apic_mode(src); + if (irq->dest_id == (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCAST)) + return false; + + if (!map) + return false; + + if (irq->dest_mode == APIC_DEST_PHYSICAL) { + if (irq->dest_id >= ARRAY_SIZE(map->phys_map)) { + *bitmap = 0; + } else { + *dst = &map->phys_map[irq->dest_id]; + *bitmap = 1; + } + return true; + } + + if (!kvm_apic_logical_map_valid(map)) + 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; + + if (!kvm_vector_hashing_enabled()) { + lowest = -1; + for_each_set_bit(i, bitmap, 16) { + if (!(*dst)[i]) + continue; + if (lowest < 0) + lowest = i; + else if (kvm_apic_compare_prio((*dst)[i]->vcpu, + (*dst)[lowest]->vcpu) < 0) + lowest = i; + } + } else { + if (!*bitmap) + return true; + + lowest = kvm_vector_to_index(irq->vector, hweight16(*bitmap), + bitmap, 16); + + if (!(*dst)[lowest]) { + kvm_apic_disabled_lapic_found(kvm); + *bitmap = 0; + return true; + } + } + + *bitmap = (lowest >= 0) ? 1 << lowest : 0; + + return true; +} + bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map) { struct kvm_apic_map *map; - unsigned long bitmap = 1; - struct kvm_lapic **dst; + unsigned long bitmap; + struct kvm_lapic **dst = NULL; int i; - bool ret, x2apic_ipi; + bool ret; *r = -1; @@ -710,86 +790,19 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, return true; } - if (irq->shorthand) - return false; - - x2apic_ipi = src && apic_x2apic_mode(src); - if (irq->dest_id == (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCAST)) - return false; - - ret = true; rcu_read_lock(); map = rcu_dereference(kvm->arch.apic_map); - if (!map) { - ret = false; - goto out; - } - - if (irq->dest_mode == APIC_DEST_PHYSICAL) { - if (irq->dest_id >= ARRAY_SIZE(map->phys_map)) - goto out; - - dst = &map->phys_map[irq->dest_id]; - } else { - u16 cid; - - if (!kvm_apic_logical_map_valid(map)) { - ret = false; - goto out; + ret = kvm_apic_map_get_dest_lapic(kvm, src, irq, map, &dst, &bitmap); + if (ret) + for_each_set_bit(i, &bitmap, 16) { + if (!dst[i]) + continue; + if (*r < 0) + *r = 0; + *r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map); } - apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap); - - if (cid >= ARRAY_SIZE(map->logical_map)) - goto out; - - dst = map->logical_map[cid]; - - if (!kvm_lowest_prio_delivery(irq)) - goto set_irq; - - if (!kvm_vector_hashing_enabled()) { - int l = -1; - for_each_set_bit(i, &bitmap, 16) { - if (!dst[i]) - continue; - if (l < 0) - l = i; - else if (kvm_apic_compare_prio(dst[i]->vcpu, - dst[l]->vcpu) < 0) - l = i; - } - bitmap = (l >= 0) ? 1 << l : 0; - } else { - int idx; - unsigned int dest_vcpus; - - dest_vcpus = hweight16(bitmap); - if (dest_vcpus == 0) - goto out; - - idx = kvm_vector_to_index(irq->vector, - dest_vcpus, &bitmap, 16); - - if (!dst[idx]) { - kvm_apic_disabled_lapic_found(kvm); - goto out; - } - - bitmap = (idx >= 0) ? 1 << idx : 0; - } - } - -set_irq: - for_each_set_bit(i, &bitmap, 16) { - if (!dst[i]) - continue; - if (*r < 0) - *r = 0; - *r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map); - } -out: rcu_read_unlock(); return ret; } @@ -812,8 +825,9 @@ bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq, struct kvm_vcpu **dest_vcpu) { struct kvm_apic_map *map; + unsigned long bitmap; + struct kvm_lapic **dst = NULL; bool ret = false; - struct kvm_lapic *dst = NULL; if (irq->shorthand) return false; @@ -821,69 +835,16 @@ bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq, rcu_read_lock(); map = rcu_dereference(kvm->arch.apic_map); - if (!map) - goto out; + if (kvm_apic_map_get_dest_lapic(kvm, NULL, irq, map, &dst, &bitmap) && + hweight16(bitmap) == 1) { + unsigned long i = find_first_bit(&bitmap, 16); - if (irq->dest_mode == APIC_DEST_PHYSICAL) { - if (irq->dest_id == 0xFF) - goto out; - - if (irq->dest_id >= ARRAY_SIZE(map->phys_map)) - goto out; - - dst = map->phys_map[irq->dest_id]; - if (dst && kvm_apic_present(dst->vcpu)) - *dest_vcpu = dst->vcpu; - else - goto out; - } else { - u16 cid; - unsigned long bitmap = 1; - int i, r = 0; - - if (!kvm_apic_logical_map_valid(map)) - goto out; - - apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap); - - if (cid >= ARRAY_SIZE(map->logical_map)) - goto out; - - if (kvm_vector_hashing_enabled() && - kvm_lowest_prio_delivery(irq)) { - int idx; - unsigned int dest_vcpus; - - dest_vcpus = hweight16(bitmap); - if (dest_vcpus == 0) - goto out; - - idx = kvm_vector_to_index(irq->vector, dest_vcpus, - &bitmap, 16); - - dst = map->logical_map[cid][idx]; - if (!dst) { - kvm_apic_disabled_lapic_found(kvm); - goto out; - } - - *dest_vcpu = dst->vcpu; - } else { - for_each_set_bit(i, &bitmap, 16) { - dst = map->logical_map[cid][i]; - if (++r == 2) - goto out; - } - - if (dst && kvm_apic_present(dst->vcpu)) - *dest_vcpu = dst->vcpu; - else - goto out; + if (dst[i]) { + *dest_vcpu = dst[i]->vcpu; + ret = true; } } - ret = true; -out: rcu_read_unlock(); return ret; }