From nobody Thu Dec 18 05:24:30 2025 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 B0E5F2343A2 for ; Tue, 10 Dec 2024 16:46:06 +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=1733849168; cv=none; b=Y/ynm4398+vWBqoYaqdkRF4sz/Pkf59M67XVB4JD8OY47MrVSH6jsBDdLkLmRvxTZP59bD+MhuVHk+q6sosiJ9oXWrDoyqebI+zEytnaROiCRd3hiHPVfMG3S0VRhkF74On1bftb/d1CFDOYdvmuriRCewwqhrLkFvtbwPHrAdc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733849168; c=relaxed/simple; bh=r66ZyEa0FFdOQ+sN/Yqfp2P2ct7nMHGpyLZwU1tN0m4=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JnTUZd+N31BgKkD4N5204SHDTWc66c8dQyw1TH12UocSWlzj3MpPdYeaIfnLCu1hAyIV4x5tdqTycSz1jrjzHd3LNei5qz0RXlwZheScIM0tOzg+OMieRGryGgiebOxxmH77lxU65S4L33sv6/+EWIeFovFiDmdEshoqyLUWt0Y= 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=bNZib6xj; 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="bNZib6xj" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1733849165; 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=5hDByM3oDkEGXRZwzZgdODbwmAtbhUeP50SV3gbQSuU=; b=bNZib6xj6V79hBW0x6+1EgLo9aw81d7uvpRKepwlyNfceA9RNRl2kGHAzHBi2zsrADsZWn pH3+zqMxZncW9CPhKcDICV3DllmSgmDj0g0FvSjoVH34pPyDOcgkeWFcjwgTINzDYc+bfW Ble71BOD1sHhQ5Y22BfU3bx9+htMzlU= Received: from mx-prod-mc-05.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-292-oPXyqo6POAybqqfOxKidoQ-1; Tue, 10 Dec 2024 11:46:04 -0500 X-MC-Unique: oPXyqo6POAybqqfOxKidoQ-1 X-Mimecast-MFC-AGG-ID: oPXyqo6POAybqqfOxKidoQ 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-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1C1471956088; Tue, 10 Dec 2024 16:46:03 +0000 (UTC) Received: from server.redhat.com (unknown [10.72.112.152]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id CBFBB19560A2; Tue, 10 Dec 2024 16:45:58 +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 v4 7/8] vhost: Add new UAPI to support change to task mode Date: Wed, 11 Dec 2024 00:41:46 +0800 Message-ID: <20241210164456.925060-8-lulu@redhat.com> In-Reply-To: <20241210164456.925060-1-lulu@redhat.com> References: <20241210164456.925060-1-lulu@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Content-Type: text/plain; charset="utf-8" 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 | 18 ++++++++++++++++++ 2 files changed, 39 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 3e9cb99da1b5..12c3bf3d1ed4 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2257,15 +2257,35 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned = int ioctl, void __user *argp) { struct eventfd_ctx *ctx; u64 p; - long r; + long r =3D 0; int i, fd; + u8 inherit_owner; =20 /* If you are not the owner, you can become one */ if (ioctl =3D=3D VHOST_SET_OWNER) { r =3D vhost_dev_set_owner(d); goto done; } + if (ioctl =3D=3D VHOST_SET_INHERIT_FROM_OWNER) { + /*inherit_owner can only be modified before owner is set*/ + if (vhost_dev_has_owner(d)) { + r =3D -EBUSY; + goto done; + } + if (copy_from_user(&inherit_owner, argp, sizeof(u8))) { + r =3D -EFAULT; + goto done; + } + /* Validate the inherit_owner value, ensuring it is either 0 or 1 */ + if (inherit_owner > 1) { + r =3D -EINVAL; + goto done; + } + + d->inherit_owner =3D (bool)inherit_owner; =20 + goto done; + } /* You must be the owner to do anything else */ r =3D vhost_dev_check_owner(d); if (r) diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h index b95dd84eef2d..d7564d62b76d 100644 --- a/include/uapi/linux/vhost.h +++ b/include/uapi/linux/vhost.h @@ -235,4 +235,22 @@ */ #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 m= ode + * + * When inherit_owner is set to 1: + * - The VHOST worker threads inherit its 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 (kt= hread) + * implementation, which may be preferred by older userspace applicati= ons that + * do not utilize the newer vhost_task concept. + */ +#define VHOST_SET_INHERIT_FROM_OWNER _IOW(VHOST_VIRTIO, 0x83, __u8) + #endif --=20 2.45.0