From patchwork Mon Dec 30 12:43:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cindy Lu X-Patchwork-Id: 13923253 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E34A31B4226 for ; Mon, 30 Dec 2024 12:45:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735562751; cv=none; b=m7LZ2Y349QqxSbg5W1m6q+0XT0SgXHae941fsn+mcdZ+1Z7OhR715L8ZlJUslK36wzdXhWaOQ5M28Z1iUVnaDUkZlCKMr0YmECoaNOuMGJYRTcL3DVd3mkwmKcCbTQTm4l57aDflfSssCgyG/QD9RBNpldcHd7C5907VcPfYa8s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735562751; c=relaxed/simple; bh=OGzW+SnQ3xR3XeDgv9+sPtHgQMdqMojO7S8Pp2pmps0=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=I4rOtSjRKwiAppVgEbbL7TCpfnD3eb2JGVc6KDrVoM5slnMny3G0n5KbQ1EP6+zicT0FlulCwEhs0ZtbaRT5BElyM++MoDh0nSWefzWazOhSl+CnNg86iXAc19pqzx2OPImmeyegVlXDZiPIRvlBIbZBiLGcbgt1/3FN1HZgr9Q= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=NQoVXVMS; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="NQoVXVMS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1735562748; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SOLNm7RgGjm+/oknkrmt1JKCoXNQL051GSrtvQZUvKg=; b=NQoVXVMSdODBuR0NJqlxTpS/G5livfgNiWFz+jruPGEMF7ArHIhYh/gdF4Sy5xJWiAbkPS 6jVfBN4Ua3GDn5JpWSyNIHXnzfchuOxkD8zSZ7I5fD5VexpX3dXoYWynygdI+i9jZIDycW tq70KHySV/ZLtGvz8i+4usrxfiXnpqA= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-378-Bsm6_zAdMOCXSGDiO3J0Jw-1; Mon, 30 Dec 2024 07:45:45 -0500 X-MC-Unique: Bsm6_zAdMOCXSGDiO3J0Jw-1 X-Mimecast-MFC-AGG-ID: Bsm6_zAdMOCXSGDiO3J0Jw Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7977519560B1; Mon, 30 Dec 2024 12:45:44 +0000 (UTC) Received: from server.redhat.com (unknown [10.72.112.25]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 759C419560A2; Mon, 30 Dec 2024 12:45:40 +0000 (UTC) From: Cindy Lu To: lulu@redhat.com, jasowang@redhat.com, mst@redhat.com, michael.christie@oracle.com, sgarzare@redhat.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Subject: [PATCH v5 5/6] vhost: Add new UAPI to support change to task mode Date: Mon, 30 Dec 2024 20:43:52 +0800 Message-ID: <20241230124445.1850997-6-lulu@redhat.com> In-Reply-To: <20241230124445.1850997-1-lulu@redhat.com> References: <20241230124445.1850997-1-lulu@redhat.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Add a new UAPI to enable setting the vhost device to task mode. The userspace application can use VHOST_SET_INHERIT_FROM_OWNER to configure the mode if necessary. This setting must be applied before VHOST_SET_OWNER, as the worker will be created in the VHOST_SET_OWNER function Signed-off-by: Cindy Lu --- drivers/vhost/vhost.c | 22 +++++++++++++++++++++- include/uapi/linux/vhost.h | 19 +++++++++++++++++++ 2 files changed, 40 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index ff17c42e2d1a..47c1329360ac 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2250,15 +2250,35 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { struct eventfd_ctx *ctx; u64 p; - long r; + long r = 0; int i, fd; + u8 inherit_owner; /* If you are not the owner, you can become one */ if (ioctl == VHOST_SET_OWNER) { r = vhost_dev_set_owner(d); goto done; } + if (ioctl == VHOST_SET_INHERIT_FROM_OWNER) { + /*inherit_owner can only be modified before owner is set*/ + if (vhost_dev_has_owner(d)) { + r = -EBUSY; + goto done; + } + if (copy_from_user(&inherit_owner, argp, sizeof(u8))) { + r = -EFAULT; + goto done; + } + /* Validate the inherit_owner value, ensuring it is either 0 or 1 */ + if (inherit_owner > 1) { + r = -EINVAL; + goto done; + } + + d->inherit_owner = (bool)inherit_owner; + goto done; + } /* You must be the owner to do anything else */ r = vhost_dev_check_owner(d); if (r) diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h index b95dd84eef2d..f5fcf0b25736 100644 --- a/include/uapi/linux/vhost.h +++ b/include/uapi/linux/vhost.h @@ -235,4 +235,23 @@ */ #define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \ struct vhost_vring_state) + +/** + * VHOST_SET_INHERIT_FROM_OWNER - Set the inherit_owner flag for the vhost device + * + * @param inherit_owner: An 8-bit value that determines the vhost thread mode + * + * When inherit_owner is set to 1 (default behavior): + * - The VHOST worker threads inherit their values/checks from + * the thread that owns the VHOST device. The vhost threads will + * be counted in the nproc rlimits. + * + * When inherit_owner is set to 0: + * - The VHOST worker threads will use the traditional kernel thread (kthread) + * implementation, which may be preferred by older userspace applications that + * do not utilize the newer vhost_task concept. + */ + +#define VHOST_SET_INHERIT_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, __u8) + #endif