From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH v7 4/8] vhost: rxtx: use queue id instead of
 constant ring index
Date: Tue, 20 Oct 2015 21:43:54 -0700
Message-ID: <20151020214354.12ac5ce1@xeon-e3>
References: <1445399294-18826-1-git-send-email-yuanhan.liu@linux.intel.com>
 <1445399294-18826-5-git-send-email-yuanhan.liu@linux.intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Cc: dev@dpdk.org, marcel@redhat.com,
 Changchun Ouyang <changchun.ouyang@intel.com>,
 "Michael S. Tsirkin" <mst@redhat.com>
To: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Return-path: <dev-bounces@dpdk.org>
Received: from mail-pa0-f54.google.com (mail-pa0-f54.google.com
 [209.85.220.54]) by dpdk.org (Postfix) with ESMTP id 2F0B26A95
 for <dev@dpdk.org>; Wed, 21 Oct 2015 06:43:45 +0200 (CEST)
Received: by pabrc13 with SMTP id rc13so42549325pab.0
 for <dev@dpdk.org>; Tue, 20 Oct 2015 21:43:44 -0700 (PDT)
In-Reply-To: <1445399294-18826-5-git-send-email-yuanhan.liu@linux.intel.com>
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

On Wed, 21 Oct 2015 11:48:10 +0800
Yuanhan Liu <yuanhan.liu@linux.intel.com> wrote:

>  
> +static inline int __attribute__((always_inline))
> +is_valid_virt_queue_idx(uint32_t virtq_idx, int is_tx, uint32_t max_qp_idx)
> +{
> +	if ((is_tx ^ (virtq_idx & 0x1)) ||
> +	    (virtq_idx >= max_qp_idx * VIRTIO_QNUM))
> +		return 0;
> +
> +	return 1;
> +}

minor nits:
 * this doesn't need to be marked as always inline, 
    that is as they say in English "shooting a fly with a bazooka"
 * prefer to just return logical result rather than have conditional:
 * for booleans prefer the <stdbool.h> type boolean.

static bool
is_valid_virt_queue_idx(uint32_t virtq_idx, bool is_tx, uint32_t max_qp_idx)
{
	return (is_tx ^ (virtq_idx & 1)) || 
		virtq_idx >= max_qp_idx * VIRTIO_QNUM;
}