From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 046DAC28EB3 for ; Thu, 6 Jun 2019 16:55:17 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id BF36820693 for ; Thu, 6 Jun 2019 16:55:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF36820693 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 69D7E4A4F7; Thu, 6 Jun 2019 12:55:16 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1MQ11Cu5Yg-v; Thu, 6 Jun 2019 12:55:14 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 30D984A4E5; Thu, 6 Jun 2019 12:55:14 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 372664A379 for ; Thu, 6 Jun 2019 12:55:13 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id BOLeHMwGDIpN for ; Thu, 6 Jun 2019 12:55:11 -0400 (EDT) Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by mm01.cs.columbia.edu (Postfix) with ESMTP id DD5944A4D5 for ; Thu, 6 Jun 2019 12:55:11 -0400 (EDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 61377165C; Thu, 6 Jun 2019 09:55:11 -0700 (PDT) Received: from filthy-habits.cambridge.arm.com (filthy-habits.cambridge.arm.com [10.1.197.61]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 92B173F690; Thu, 6 Jun 2019 09:55:09 -0700 (PDT) From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Subject: [PATCH 3/8] KVM: arm/arm64: vgic-its: Cache successful MSI->LPI translation Date: Thu, 6 Jun 2019 17:54:50 +0100 Message-Id: <20190606165455.162478-4-marc.zyngier@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190606165455.162478-1-marc.zyngier@arm.com> References: <20190606165455.162478-1-marc.zyngier@arm.com> MIME-Version: 1.0 Cc: "Raslan, KarimAllah" X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On a successful translation, preserve the parameters in the LPI translation cache. Each translation is reusing the last slot in the list, naturally evincting the least recently used entry. Signed-off-by: Marc Zyngier --- virt/kvm/arm/vgic/vgic-its.c | 41 ++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 5758504fd934..bc370b6c5afa 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -538,6 +538,45 @@ static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm, return 0; } +static void vgic_its_cache_translation(struct kvm *kvm, struct vgic_its *its, + u32 devid, u32 eventid, + struct vgic_irq *irq) +{ + struct vgic_dist *dist = &kvm->arch.vgic; + struct vgic_translation_cache_entry *cte; + unsigned long flags; + + /* Do not cache a directly injected interrupt */ + if (irq->hw) + return; + + raw_spin_lock_irqsave(&dist->lpi_list_lock, flags); + + /* Always reuse the last entry (LRU policy) */ + cte = list_last_entry(&dist->lpi_translation_cache, + typeof(*cte), entry); + + /* + * Caching the translation implies having an extra reference + * to the interrupt, so drop the potential reference on what + * was in the cache, and increment it on the new interrupt. + */ + if (cte->irq) + __vgic_put_lpi_locked(kvm, cte->irq); + + vgic_get_irq_kref(irq); + + cte->db = its->vgic_its_base + GITS_TRANSLATER; + cte->devid = devid; + cte->eventid = eventid; + cte->irq = irq; + + /* Move the new translation to the head of the list */ + list_move(&cte->entry, &dist->lpi_translation_cache); + + raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags); +} + int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its, u32 devid, u32 eventid, struct vgic_irq **irq) { @@ -558,6 +597,8 @@ int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its, if (!vcpu->arch.vgic_cpu.lpis_enabled) return -EBUSY; + vgic_its_cache_translation(kvm, its, devid, eventid, ite->irq); + *irq = ite->irq; return 0; } -- 2.20.1 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm