From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= 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> References: <1462568045-31085-1-git-send-email-rkrcmar@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Paolo Bonzini , "Lan, Tianyu" , Igor Mammedov , Jan Kiszka , Peter Xu To: kvm@vger.kernel.org Return-path: 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 In-Reply-To: <1462568045-31085-1-git-send-email-rkrcmar@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: 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 =3D NULL' had to be added to silence GCC. GCC might complain about potential NULL access in the future, because i= t missed conditions that avoided uninitialized uses of dst. Signed-off-by: Radim Kr=C4=8Dm=C3=A1=C5=99 --- 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) } } =20 +/* If kvm_apic_map_get_dest_lapic returns true, then *bitmap encodes a= ccessible + * elements in the *dst array. Those are destinations for the interru= pt. + */ +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 =3D=3D APIC_DEST_SELF) { + *dst =3D &src; + *bitmap =3D 1; + return true; + } else if (irq->shorthand) + return false; + + x2apic_ipi =3D src && apic_x2apic_mode(src); + if (irq->dest_id =3D=3D (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCA= ST)) + return false; + + if (!map) + return false; + + if (irq->dest_mode =3D=3D APIC_DEST_PHYSICAL) { + if (irq->dest_id >=3D ARRAY_SIZE(map->phys_map)) { + *bitmap =3D 0; + } else { + *dst =3D &map->phys_map[irq->dest_id]; + *bitmap =3D 1; + } + return true; + } + + if (!kvm_apic_logical_map_valid(map)) + return false; + + apic_logical_id(map, irq->dest_id, &cid, (u16 *)bitmap); + + if (cid >=3D ARRAY_SIZE(map->logical_map)) { + *bitmap =3D 0; + return true; + } + + *dst =3D map->logical_map[cid]; + + if (!kvm_lowest_prio_delivery(irq)) + return true; + + if (!kvm_vector_hashing_enabled()) { + lowest =3D -1; + for_each_set_bit(i, bitmap, 16) { + if (!(*dst)[i]) + continue; + if (lowest < 0) + lowest =3D i; + else if (kvm_apic_compare_prio((*dst)[i]->vcpu, + (*dst)[lowest]->vcpu) < 0) + lowest =3D i; + } + } else { + if (!*bitmap) + return true; + + lowest =3D kvm_vector_to_index(irq->vector, hweight16(*bitmap), + bitmap, 16); + + if (!(*dst)[lowest]) { + kvm_apic_disabled_lapic_found(kvm); + *bitmap =3D 0; + return true; + } + } + + *bitmap =3D (lowest >=3D 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 =3D 1; - struct kvm_lapic **dst; + unsigned long bitmap; + struct kvm_lapic **dst =3D NULL; int i; - bool ret, x2apic_ipi; + bool ret; =20 *r =3D -1; =20 @@ -710,86 +790,19 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kv= m, struct kvm_lapic *src, return true; } =20 - if (irq->shorthand) - return false; - - x2apic_ipi =3D src && apic_x2apic_mode(src); - if (irq->dest_id =3D=3D (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCA= ST)) - return false; - - ret =3D true; rcu_read_lock(); map =3D rcu_dereference(kvm->arch.apic_map); =20 - if (!map) { - ret =3D false; - goto out; - } - - if (irq->dest_mode =3D=3D APIC_DEST_PHYSICAL) { - if (irq->dest_id >=3D ARRAY_SIZE(map->phys_map)) - goto out; - - dst =3D &map->phys_map[irq->dest_id]; - } else { - u16 cid; - - if (!kvm_apic_logical_map_valid(map)) { - ret =3D false; - goto out; + ret =3D 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 =3D 0; + *r +=3D kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map); } =20 - apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap); - - if (cid >=3D ARRAY_SIZE(map->logical_map)) - goto out; - - dst =3D map->logical_map[cid]; - - if (!kvm_lowest_prio_delivery(irq)) - goto set_irq; - - if (!kvm_vector_hashing_enabled()) { - int l =3D -1; - for_each_set_bit(i, &bitmap, 16) { - if (!dst[i]) - continue; - if (l < 0) - l =3D i; - else if (kvm_apic_compare_prio(dst[i]->vcpu, - dst[l]->vcpu) < 0) - l =3D i; - } - bitmap =3D (l >=3D 0) ? 1 << l : 0; - } else { - int idx; - unsigned int dest_vcpus; - - dest_vcpus =3D hweight16(bitmap); - if (dest_vcpus =3D=3D 0) - goto out; - - idx =3D kvm_vector_to_index(irq->vector, - dest_vcpus, &bitmap, 16); - - if (!dst[idx]) { - kvm_apic_disabled_lapic_found(kvm); - goto out; - } - - bitmap =3D (idx >=3D 0) ? 1 << idx : 0; - } - } - -set_irq: - for_each_set_bit(i, &bitmap, 16) { - if (!dst[i]) - continue; - if (*r < 0) - *r =3D 0; - *r +=3D 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 =3D NULL; bool ret =3D false; - struct kvm_lapic *dst =3D NULL; =20 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 =3D rcu_dereference(kvm->arch.apic_map); =20 - if (!map) - goto out; + if (kvm_apic_map_get_dest_lapic(kvm, NULL, irq, map, &dst, &bitmap) &= & + hweight16(bitmap) =3D=3D 1) { + unsigned long i =3D find_first_bit(&bitmap, 16); =20 - if (irq->dest_mode =3D=3D APIC_DEST_PHYSICAL) { - if (irq->dest_id =3D=3D 0xFF) - goto out; - - if (irq->dest_id >=3D ARRAY_SIZE(map->phys_map)) - goto out; - - dst =3D map->phys_map[irq->dest_id]; - if (dst && kvm_apic_present(dst->vcpu)) - *dest_vcpu =3D dst->vcpu; - else - goto out; - } else { - u16 cid; - unsigned long bitmap =3D 1; - int i, r =3D 0; - - if (!kvm_apic_logical_map_valid(map)) - goto out; - - apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap); - - if (cid >=3D 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 =3D hweight16(bitmap); - if (dest_vcpus =3D=3D 0) - goto out; - - idx =3D kvm_vector_to_index(irq->vector, dest_vcpus, - &bitmap, 16); - - dst =3D map->logical_map[cid][idx]; - if (!dst) { - kvm_apic_disabled_lapic_found(kvm); - goto out; - } - - *dest_vcpu =3D dst->vcpu; - } else { - for_each_set_bit(i, &bitmap, 16) { - dst =3D map->logical_map[cid][i]; - if (++r =3D=3D 2) - goto out; - } - - if (dst && kvm_apic_present(dst->vcpu)) - *dest_vcpu =3D dst->vcpu; - else - goto out; + if (dst[i]) { + *dest_vcpu =3D dst[i]->vcpu; + ret =3D true; } } =20 - ret =3D true; -out: rcu_read_unlock(); return ret; } --=20 2.8.2