From mboxrd@z Thu Jan 1 00:00:00 1970
Return-Path: <dev-bounces@dpdk.org>
Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124])
by inbox.dpdk.org (Postfix) with ESMTP id 29C6243BEE;
Mon, 26 Feb 2024 16:47:06 +0100 (CET)
Received: from mails.dpdk.org (localhost [127.0.0.1])
by mails.dpdk.org (Postfix) with ESMTP id D0736402C8;
Mon, 26 Feb 2024 16:47:05 +0100 (CET)
Received: from us-smtp-delivery-124.mimecast.com
(us-smtp-delivery-124.mimecast.com [170.10.129.124])
by mails.dpdk.org (Postfix) with ESMTP id D28B940144
for <dev@dpdk.org>; Mon, 26 Feb 2024 16:47:04 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;
s=mimecast20190719; t=1708962424;
h=from:from:reply-to:subject:subject:date:date:message-id:message-id:
to:to:cc:cc:mime-version:mime-version:content-type:content-type:
content-transfer-encoding:content-transfer-encoding:
in-reply-to:in-reply-to:references:references;
bh=zfu5qp4dSQ0rWPnAO9HYhg1+KaTNI7WlqveZsE/2r4M=;
b=ZkCiAaT+DMT6OanA0vXJRsIwWzBtl51AYQP6OYpoX4WzfNLUpa8X6yDVwHEnzG2B+fQn+d
CWsHBIIlbW51lb02StNDiGW9UpCjm/31YRRWfSJQ54+Vb3EirsE9fDYUhjAoc6NlVX3UUX
U56GYqcyi6CMzNf7epFfQrSKyEGB36s=
Received: from mail-lj1-f198.google.com (mail-lj1-f198.google.com
[209.85.208.198]) by relay.mimecast.com with ESMTP with STARTTLS
(version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id
us-mta-665-ZH96xHhoOkyW6dzCcuRFgw-1; Mon, 26 Feb 2024 10:47:02 -0500
X-MC-Unique: ZH96xHhoOkyW6dzCcuRFgw-1
Received: by mail-lj1-f198.google.com with SMTP id
38308e7fff4ca-2d22adb2b88so25199421fa.0
for <dev@dpdk.org>; Mon, 26 Feb 2024 07:47:02 -0800 (PST)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20230601; t=1708962421; x=1709567221;
h=content-transfer-encoding:cc:to:subject:message-id:date:from
:in-reply-to:references:mime-version:x-gm-message-state:from:to:cc
:subject:date:message-id:reply-to;
bh=zfu5qp4dSQ0rWPnAO9HYhg1+KaTNI7WlqveZsE/2r4M=;
b=RwxXY3aoK24CUsRfmBw69LePHxIR6S/dK/hjtwim9NweN4ZOiVB1vy/29Jo+c5LJXR
bq2y5y0GZffc+Es5wgwz/olh1N6ZmtC9FvYn+LQoFNFylmQMTm6G7RiX6NgICgNK/8DA
dyTDkyLTvSTtVJNDXt/Jsqy3jcvpMXwdoNBBGDM2OWfMto93Fn9k4m5YYXyg/HWJjctw
Az26UuRPaGOxMbpvSeIaIcjq5RZ9qMKGugCuC0OB7UkSkL/+2LfjlkVPYt5TJVYRhnJa
v5Pj9orNG6odEt2T5maCTfTPTHP8oP6eQ6pBbwDXJSHPUGXCBOZiRVBTuC8r7Yvkjl4L
Y5qw==
X-Gm-Message-State: AOJu0YxYKG+ukica214u7MYj42sqeAUE5qe+Gw+2lLPNaz/oRlk2g386
2jdSerI0VyPPrpFonO1C4iVrHRDEj4yr+qROgkh9SbsTdn+D+co2M8tuO69qR8lvrs19WR8nr1P
OLa2r0bVCc1U+45WWl7IDGvvJlqgSxn8Eeatml+c0JKKW6/+w+hyFvTZogA3PHY55kN1WzmlU9+
b9j+HREImIkcSoUPI=
X-Received: by 2002:a2e:b8c7:0:b0:2d2:4ee4:c8a5 with SMTP id
s7-20020a2eb8c7000000b002d24ee4c8a5mr4886373ljp.50.1708962421327;
Mon, 26 Feb 2024 07:47:01 -0800 (PST)
X-Google-Smtp-Source: AGHT+IE6wk4YovQVfXgTC6zO4hzzuJqe8JZLD5FyQIK8yT15bRYKndQTXohuR3oY4MUz7cxJAOB045txBwtEXJK9i20=
X-Received: by 2002:a2e:b8c7:0:b0:2d2:4ee4:c8a5 with SMTP id
s7-20020a2eb8c7000000b002d24ee4c8a5mr4886353ljp.50.1708962421018; Mon, 26 Feb
2024 07:47:01 -0800 (PST)
MIME-Version: 1.0
References: <20231023095520.2864868-1-david.marchand@redhat.com>
<20231205094536.2816720-1-david.marchand@redhat.com>
<20231205094536.2816720-5-david.marchand@redhat.com>
<4668504.U7HbjWM52l@thomas>
In-Reply-To: <4668504.U7HbjWM52l@thomas>
From: David Marchand <david.marchand@redhat.com>
Date: Mon, 26 Feb 2024 16:46:49 +0100
Message-ID: <CAJFAV8x8iesVNEn9eefEgf9nJdfuQW=h1V1z3wE-NMK5ajgpHg@mail.gmail.com>
Subject: Re: [PATCH v2 5/5] vhost: enhance virtqueue access lock asserts
To: Thomas Monjalon <thomas@monjalon.net>
Cc: dev@dpdk.org, Eelco Chaudron <echaudro@redhat.com>,
Maxime Coquelin <maxime.coquelin@redhat.com>, Chenbo Xia <chenbox@nvidia.com>,
Tyler Retzlaff <roretzla@linux.microsoft.com>,
Stephen Hemminger <stephen@networkplumber.org>
X-Mimecast-Spam-Score: 0
X-Mimecast-Originator: redhat.com
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
<mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
<mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
On Mon, Feb 19, 2024 at 11:52=E2=80=AFAM Thomas Monjalon <thomas@monjalon.n=
et> wrote:
>
> 05/12/2023 10:45, David Marchand:
> > +#define VHOST_USER_ASSERT_LOCK(dev, vq, id) do { \
> > + RTE_BUILD_BUG_ON(!vhost_message_handlers[id].lock_all_qps); \
> > + vq_assert_lock(dev, vq); \
> > +} while (0)
>
> Since "eal: enhance compile-time checks using C11 assert",
> it is not allowed to have non-constant check in RTE_BUILD_BUG_ON:
>
> lib/vhost/vhost_user.c:413:25: note: in expansion of macro 'VHOST_USER_AS=
SERT_LOCK'
> lib/vhost/vhost_user.c: In function 'vhost_user_set_vring_addr':
> lib/eal/include/rte_common.h:518:56: error: expression in static assertio=
n is not constant
> #define RTE_BUILD_BUG_ON(condition) do { static_assert(!(condition), #c=
ondition); } while (0)
>
> I suppose we can make this check at compile-time with few adjustments.
> For -rc1, I am dropping this patch.
Iiuc, an array content is not constant (from a compiler pov) unless
the elements are integers.
I suspect there is some gcc-specific implementation that could work,
since with the previous implementation of RTE_BUILD_BUG_ON, this check
was working with both gcc and clang...
But I could not find how to.
I have an alternate solution using enums with the existing macros..
I'll post a new revision.
--=20
David Marchand