From patchwork Tue Jul 28 04:24:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhu, Lingshan" X-Patchwork-Id: 11688095 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E4B28722 for ; Tue, 28 Jul 2020 04:28:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D115E206D4 for ; Tue, 28 Jul 2020 04:28:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726869AbgG1E2o (ORCPT ); Tue, 28 Jul 2020 00:28:44 -0400 Received: from mga05.intel.com ([192.55.52.43]:10281 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726854AbgG1E2o (ORCPT ); Tue, 28 Jul 2020 00:28:44 -0400 IronPort-SDR: 7HGj4vWYy+2TTnofkQULm4lUKFv/aJAnCC8AtTTlEJDPKTnzvFV0wfkzWVpQ3lhlwqIU/xjI6B eEyfNT8twB2g== X-IronPort-AV: E=McAfee;i="6000,8403,9695"; a="236011099" X-IronPort-AV: E=Sophos;i="5.75,405,1589266800"; d="scan'208";a="236011099" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jul 2020 21:28:42 -0700 IronPort-SDR: DQEtV0Uuq64u3nxApgGRC3gHaxgfOcfv1U8Lxs9a+syeYhReK2nEjzYiz0PrS2DJ82i03yLAaL M3XZUk/gWVQA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,405,1589266800"; d="scan'208";a="290037317" Received: from unknown (HELO localhost.localdomain.bj.intel.com) ([10.240.192.131]) by orsmga006.jf.intel.com with ESMTP; 27 Jul 2020 21:28:32 -0700 From: Zhu Lingshan To: jasowang@redhat.com, alex.williamson@redhat.com, mst@redhat.com, pbonzini@redhat.com, sean.j.christopherson@intel.com, wanpengli@tencent.com Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, eli@mellanox.com, shahafs@mellanox.com, parav@mellanox.com, Zhu Lingshan Subject: [PATCH V4 4/6] vhost_vdpa: implement IRQ offloading in vhost_vdpa Date: Tue, 28 Jul 2020 12:24:03 +0800 Message-Id: <20200728042405.17579-5-lingshan.zhu@intel.com> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20200728042405.17579-1-lingshan.zhu@intel.com> References: <20200728042405.17579-1-lingshan.zhu@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch introduce a set of functions for setup/unsetup and update irq offloading respectively by register/unregister and re-register the irq_bypass_producer. With these functions, this commit can setup/unsetup irq offloading through setting DRIVER_OK/!DRIVER_OK, and update irq offloading through SET_VRING_CALL. Signed-off-by: Zhu Lingshan Suggested-by: Jason Wang --- drivers/vhost/Kconfig | 1 + drivers/vhost/vdpa.c | 79 ++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 79 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index d3688c6afb87..587fbae06182 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -65,6 +65,7 @@ config VHOST_VDPA tristate "Vhost driver for vDPA-based backend" depends on EVENTFD select VHOST + select IRQ_BYPASS_MANAGER depends on VDPA help This kernel module can be loaded in host kernel to accelerate diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index df3cf386b0cd..1dccced321f8 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -115,6 +115,55 @@ static irqreturn_t vhost_vdpa_config_cb(void *private) return IRQ_HANDLED; } +static void vhost_vdpa_setup_vq_irq(struct vhost_vdpa *v, int qid) +{ + struct vhost_virtqueue *vq = &v->vqs[qid]; + const struct vdpa_config_ops *ops = v->vdpa->config; + struct vdpa_device *vdpa = v->vdpa; + int ret, irq; + + spin_lock(&vq->call_ctx.ctx_lock); + irq = ops->get_vq_irq(vdpa, qid); + if (!vq->call_ctx.ctx || irq == -EINVAL) { + spin_unlock(&vq->call_ctx.ctx_lock); + return; + } + + vq->call_ctx.producer.token = vq->call_ctx.ctx; + vq->call_ctx.producer.irq = irq; + ret = irq_bypass_register_producer(&vq->call_ctx.producer); + spin_unlock(&vq->call_ctx.ctx_lock); +} + +static void vhost_vdpa_unsetup_vq_irq(struct vhost_vdpa *v, int qid) +{ + struct vhost_virtqueue *vq = &v->vqs[qid]; + + spin_lock(&vq->call_ctx.ctx_lock); + irq_bypass_unregister_producer(&vq->call_ctx.producer); + spin_unlock(&vq->call_ctx.ctx_lock); +} + +static void vhost_vdpa_update_vq_irq(struct vhost_virtqueue *vq) +{ + spin_lock(&vq->call_ctx.ctx_lock); + /* + * if it has a non-zero irq, means there is a + * previsouly registered irq_bypass_producer, + * we should update it when ctx (its token) + * changes. + */ + if (!vq->call_ctx.producer.irq) { + spin_unlock(&vq->call_ctx.ctx_lock); + return; + } + + irq_bypass_unregister_producer(&vq->call_ctx.producer); + vq->call_ctx.producer.token = vq->call_ctx.ctx; + irq_bypass_register_producer(&vq->call_ctx.producer); + spin_unlock(&vq->call_ctx.ctx_lock); +} + static void vhost_vdpa_reset(struct vhost_vdpa *v) { struct vdpa_device *vdpa = v->vdpa; @@ -155,11 +204,15 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp) { struct vdpa_device *vdpa = v->vdpa; const struct vdpa_config_ops *ops = vdpa->config; - u8 status; + u8 status, status_old; + int i, nvqs; if (copy_from_user(&status, statusp, sizeof(status))) return -EFAULT; + status_old = ops->get_status(vdpa); + nvqs = v->nvqs; + /* * Userspace shouldn't remove status bits unless reset the * status to 0. @@ -167,6 +220,15 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp) if (status != 0 && (ops->get_status(vdpa) & ~status) != 0) return -EINVAL; + /* vq irq is not expected to be changed once DRIVER_OK is set */ + if ((status & VIRTIO_CONFIG_S_DRIVER_OK) && !(status_old & VIRTIO_CONFIG_S_DRIVER_OK)) + for (i = 0; i < nvqs; i++) + vhost_vdpa_setup_vq_irq(v, i); + + if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK)) + for (i = 0; i < nvqs; i++) + vhost_vdpa_unsetup_vq_irq(v, i); + ops->set_status(vdpa, status); return 0; @@ -332,6 +394,7 @@ static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp) return 0; } + static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd, void __user *argp) { @@ -390,6 +453,7 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd, cb.private = NULL; } ops->set_vq_cb(vdpa, idx, &cb); + vhost_vdpa_update_vq_irq(vq); break; case VHOST_SET_VRING_NUM: @@ -765,6 +829,18 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep) return r; } +static void vhost_vdpa_clean_irq(struct vhost_vdpa *v) +{ + struct vhost_virtqueue *vq; + int i; + + for (i = 0; i < v->nvqs; i++) { + vq = &v->vqs[i]; + if (vq->call_ctx.producer.irq) + irq_bypass_unregister_producer(&vq->call_ctx.producer); + } +} + static int vhost_vdpa_release(struct inode *inode, struct file *filep) { struct vhost_vdpa *v = filep->private_data; @@ -777,6 +853,7 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep) vhost_vdpa_iotlb_free(v); vhost_vdpa_free_domain(v); vhost_vdpa_config_put(v); + vhost_vdpa_clean_irq(v); vhost_dev_cleanup(&v->vdev); kfree(v->vdev.vqs); mutex_unlock(&d->mutex);