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[2001:1868:205::9]) by mx.google.com with ESMTPS id oo9si2668067pac.212.2015.11.04.07.03.27 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 04 Nov 2015 07:03:27 -0800 (PST) Received-SPF: pass (google.com: domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org; dkim=neutral (body hash did not verify) header.i=@linaro_org.20150623.gappssmtp.com Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZtzZ0-0007BN-I9; Wed, 04 Nov 2015 15:01:26 +0000 Received: from merlin.infradead.org ([2001:4978:20e::2]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZtzRV-0005HT-Ba for linux-arm-kernel@bombadil.infradead.org; Wed, 04 Nov 2015 14:53:41 +0000 Received: from mail-wm0-x231.google.com ([2a00:1450:400c:c09::231]) by merlin.infradead.org with esmtps (Exim 4.85 #2 (Red Hat Linux)) id 1ZtzRT-0001O2-Ng for linux-arm-kernel@lists.infradead.org; Wed, 04 Nov 2015 14:53:40 +0000 Received: by wmff134 with SMTP id f134so43614064wmf.0 for ; Wed, 04 Nov 2015 06:53:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro_org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Qn1XBYjGj/amNfa5m+njA8ucUS0x3Yp5Se5mxnnPECw=; b=PzZ/RMfTsUOqLEvvUMWIoIpfsazH9EZQnajE905FUyekF9U4Vq55DLUrjvYAxcY4y3 cfUAjValJWIuBp6pYPMNUsvQQie7W3Yv9MWHAetgyS3shwr0TqnOoNPxMixXx7xVhMci CtGPRoj8gg8pg53jEKfOiUuvVCzBbVTPNxeQ/JLd8DBJ9as9O4plfQyySNtF5P9H4HfR 54sRFE18bjv1Vy+I+ZUZPVWwjGPTgV0tY0xtSy27xL9CsHO+D3CTTFZfCNVPI/FSFFgZ X3aYhMRGL1JRMUMJ/lsV68oW6vKMwWp3u9Oro6JWdrZPwrMyn2Q2nAznTCLw4QUt6kIe EZyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=Qn1XBYjGj/amNfa5m+njA8ucUS0x3Yp5Se5mxnnPECw=; b=Wy6rzPUwMer7ZPcg+N08sMNL2NePNphCYL3u/z61zNr4sO/OiDT9JhxhvIcxbeFFeP 8CUObAp1V4P2ELcug+Dc1rrrZ88G2SxrHytKF2p9xuxSlA2IVMyLaDLV9uWg3c/TXVKW wwYPXbbLkKlRB0ZxCzUFZfFD/NGvzStYXhcCDBlIyZY3b0RsRrNCZGUn4/64wkAyeUWH orbhk80+BUaPTOVHbwr7WjIboe252z3mVUnhmsaes8ytfnYJiTV2U7lBgw7t3dhuoEaU M4UwZ3PLtG3Qx0pT+XHyI2TRI75PvI6v8J9qZROUshMv3oW7YDFYtkDO1CoqmhLTb8zF AjvQ== X-Gm-Message-State: ALoCoQnLvzn+bl4Kfm5zxzkEve/UHUlU1ZPwpXhLEDfXaz13xGcKaD+3Ats3FcOC2fyrSVQ5rA5d X-Received: by 10.28.88.203 with SMTP id m194mr3826843wmb.68.1446648797833; Wed, 04 Nov 2015 06:53:17 -0800 (PST) Received: from localhost.localdomain ([94.18.191.146]) by smtp.gmail.com with ESMTPSA id e9sm1985081wjw.8.2015.11.04.06.53.16 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 04 Nov 2015 06:53:17 -0800 (PST) From: Christoffer Dall To: Paolo Bonzini , kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PULL 19/21] KVM: arm/arm64: Optimize away redundant LR tracking Date: Wed, 4 Nov 2015 15:49:58 +0100 Message-Id: <1446648600-27297-20-git-send-email-christoffer.dall@linaro.org> X-Mailer: git-send-email 2.1.2.330.g565301e.dirty In-Reply-To: <1446648600-27297-1-git-send-email-christoffer.dall@linaro.org> References: <1446648600-27297-1-git-send-email-christoffer.dall@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151104_095340_012752_6C147DD9 X-CRM114-Status: GOOD ( 23.78 ) X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.4.1 on merlin.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [2a00:1450:400c:c09:0:0:0:231 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marc Zyngier , Pavel Fedin , Christoffer Dall MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org From: Pavel Fedin Currently we use vgic_irq_lr_map in order to track which LRs hold which IRQs, and lr_used bitmap in order to track which LRs are used or free. vgic_irq_lr_map is actually used only for piggy-back optimization, and can be easily replaced by iteration over lr_used. This is good because in future, when LPI support is introduced, number of IRQs will grow up to at least 16384, while numbers from 1024 to 8192 are never going to be used. This would be a huge memory waste. In its turn, lr_used is also completely redundant since ae705930fca6322600690df9dc1c7d0516145a93 ("arm/arm64: KVM: Keep elrsr/aisr in sync with software model"), because together with lr_used we also update elrsr. This allows to easily replace lr_used with elrsr, inverting all conditions (because in elrsr '1' means 'free'). Signed-off-by: Pavel Fedin Signed-off-by: Christoffer Dall --- include/kvm/arm_vgic.h | 6 ------ virt/kvm/arm/vgic-v2.c | 1 + virt/kvm/arm/vgic-v3.c | 1 + virt/kvm/arm/vgic.c | 53 ++++++++++++++------------------------------------ 4 files changed, 17 insertions(+), 44 deletions(-) -- 2.1.2.330.g565301e.dirty _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 8065801..3936bf8 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -295,9 +295,6 @@ struct vgic_v3_cpu_if { }; struct vgic_cpu { - /* per IRQ to LR mapping */ - u8 *vgic_irq_lr_map; - /* Pending/active/both interrupts on this VCPU */ DECLARE_BITMAP(pending_percpu, VGIC_NR_PRIVATE_IRQS); DECLARE_BITMAP(active_percpu, VGIC_NR_PRIVATE_IRQS); @@ -308,9 +305,6 @@ struct vgic_cpu { unsigned long *active_shared; unsigned long *pend_act_shared; - /* Bitmap of used/free list registers */ - DECLARE_BITMAP(lr_used, VGIC_V2_MAX_LRS); - /* Number of list registers on this CPU */ int nr_lr; diff --git a/virt/kvm/arm/vgic-v2.c b/virt/kvm/arm/vgic-v2.c index 8d7b04d..c0f5d7f 100644 --- a/virt/kvm/arm/vgic-v2.c +++ b/virt/kvm/arm/vgic-v2.c @@ -158,6 +158,7 @@ static void vgic_v2_enable(struct kvm_vcpu *vcpu) * anyway. */ vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = 0; + vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr = ~0; /* Get the show on the road... */ vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr = GICH_HCR_EN; diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c index 7dd5d62..92003cb 100644 --- a/virt/kvm/arm/vgic-v3.c +++ b/virt/kvm/arm/vgic-v3.c @@ -193,6 +193,7 @@ static void vgic_v3_enable(struct kvm_vcpu *vcpu) * anyway. */ vgic_v3->vgic_vmcr = 0; + vgic_v3->vgic_elrsr = ~0; /* * If we are emulating a GICv3, we do it in an non-GICv2-compatible diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index d4669eb..265a410 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -108,6 +108,7 @@ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu); static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu); static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr); static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc); +static u64 vgic_get_elrsr(struct kvm_vcpu *vcpu); static struct irq_phys_map *vgic_irq_map_search(struct kvm_vcpu *vcpu, int virt_irq); static int compute_pending_for_cpu(struct kvm_vcpu *vcpu); @@ -691,9 +692,11 @@ bool vgic_handle_cfg_reg(u32 *reg, struct kvm_exit_mmio *mmio, void vgic_unqueue_irqs(struct kvm_vcpu *vcpu) { struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; + u64 elrsr = vgic_get_elrsr(vcpu); + unsigned long *elrsr_ptr = u64_to_bitmask(&elrsr); int i; - for_each_set_bit(i, vgic_cpu->lr_used, vgic_cpu->nr_lr) { + for_each_clear_bit(i, elrsr_ptr, vgic_cpu->nr_lr) { struct vgic_lr lr = vgic_get_lr(vcpu, i); /* @@ -1098,7 +1101,6 @@ static inline void vgic_enable(struct kvm_vcpu *vcpu) static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu) { - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; struct vgic_lr vlr = vgic_get_lr(vcpu, lr_nr); /* @@ -1112,8 +1114,6 @@ static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu) vlr.state = 0; vgic_set_lr(vcpu, lr_nr, vlr); - clear_bit(lr_nr, vgic_cpu->lr_used); - vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY; vgic_sync_lr_elrsr(vcpu, lr_nr, vlr); } @@ -1128,10 +1128,11 @@ static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu) */ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu) { - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; + u64 elrsr = vgic_get_elrsr(vcpu); + unsigned long *elrsr_ptr = u64_to_bitmask(&elrsr); int lr; - for_each_set_bit(lr, vgic_cpu->lr_used, vgic->nr_lr) { + for_each_clear_bit(lr, elrsr_ptr, vgic->nr_lr) { struct vgic_lr vlr = vgic_get_lr(vcpu, lr); if (!vgic_irq_is_enabled(vcpu, vlr.irq)) { @@ -1188,8 +1189,9 @@ static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq, */ bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq) { - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + u64 elrsr = vgic_get_elrsr(vcpu); + unsigned long *elrsr_ptr = u64_to_bitmask(&elrsr); struct vgic_lr vlr; int lr; @@ -1200,28 +1202,22 @@ bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq) kvm_debug("Queue IRQ%d\n", irq); - lr = vgic_cpu->vgic_irq_lr_map[irq]; - /* Do we have an active interrupt for the same CPUID? */ - if (lr != LR_EMPTY) { + for_each_clear_bit(lr, elrsr_ptr, vgic->nr_lr) { vlr = vgic_get_lr(vcpu, lr); - if (vlr.source == sgi_source_id) { + if (vlr.irq == irq && vlr.source == sgi_source_id) { kvm_debug("LR%d piggyback for IRQ%d\n", lr, vlr.irq); - BUG_ON(!test_bit(lr, vgic_cpu->lr_used)); vgic_queue_irq_to_lr(vcpu, irq, lr, vlr); return true; } } /* Try to use another LR for this interrupt */ - lr = find_first_zero_bit((unsigned long *)vgic_cpu->lr_used, - vgic->nr_lr); + lr = find_first_bit(elrsr_ptr, vgic->nr_lr); if (lr >= vgic->nr_lr) return false; kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id); - vgic_cpu->vgic_irq_lr_map[irq] = lr; - set_bit(lr, vgic_cpu->lr_used); vlr.irq = irq; vlr.source = sgi_source_id; @@ -1456,7 +1452,6 @@ static bool vgic_sync_hwirq(struct kvm_vcpu *vcpu, int lr, struct vgic_lr vlr) /* Sync back the VGIC state after a guest run */ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) { - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; struct vgic_dist *dist = &vcpu->kvm->arch.vgic; u64 elrsr; unsigned long *elrsr_ptr; @@ -1469,22 +1464,10 @@ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) /* Deal with HW interrupts, and clear mappings for empty LRs */ for (lr = 0; lr < vgic->nr_lr; lr++) { - struct vgic_lr vlr; - - if (!test_bit(lr, vgic_cpu->lr_used)) - continue; - - vlr = vgic_get_lr(vcpu, lr); - if (vgic_sync_hwirq(vcpu, lr, vlr)) - level_pending = true; - - if (!test_bit(lr, elrsr_ptr)) - continue; - - clear_bit(lr, vgic_cpu->lr_used); + struct vgic_lr vlr = vgic_get_lr(vcpu, lr); + level_pending |= vgic_sync_hwirq(vcpu, lr, vlr); BUG_ON(vlr.irq >= dist->nr_irqs); - vgic_cpu->vgic_irq_lr_map[vlr.irq] = LR_EMPTY; } /* Check if we still have something up our sleeve... */ @@ -1912,12 +1895,10 @@ void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu) kfree(vgic_cpu->pending_shared); kfree(vgic_cpu->active_shared); kfree(vgic_cpu->pend_act_shared); - kfree(vgic_cpu->vgic_irq_lr_map); vgic_destroy_irq_phys_map(vcpu->kvm, &vgic_cpu->irq_phys_map_list); vgic_cpu->pending_shared = NULL; vgic_cpu->active_shared = NULL; vgic_cpu->pend_act_shared = NULL; - vgic_cpu->vgic_irq_lr_map = NULL; } static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs) @@ -1928,18 +1909,14 @@ static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs) vgic_cpu->pending_shared = kzalloc(sz, GFP_KERNEL); vgic_cpu->active_shared = kzalloc(sz, GFP_KERNEL); vgic_cpu->pend_act_shared = kzalloc(sz, GFP_KERNEL); - vgic_cpu->vgic_irq_lr_map = kmalloc(nr_irqs, GFP_KERNEL); if (!vgic_cpu->pending_shared || !vgic_cpu->active_shared - || !vgic_cpu->pend_act_shared - || !vgic_cpu->vgic_irq_lr_map) { + || !vgic_cpu->pend_act_shared) { kvm_vgic_vcpu_destroy(vcpu); return -ENOMEM; } - memset(vgic_cpu->vgic_irq_lr_map, LR_EMPTY, nr_irqs); - /* * Store the number of LRs per vcpu, so we don't have to go * all the way to the distributor structure to find out. Only