Re: [dpdk-dev] [RFC v8] /net: memory interface (memif)

From: Stephen Hemminger <stephen@networkplumber.org>
To: Jakub Grajciar <jgrajcia@cisco.com>
Cc: <dev@dpdk.org>
Subject: Re: [dpdk-dev] [RFC v8] /net: memory interface (memif)
Date: Thu, 16 May 2019 08:25:42 -0700	[thread overview]
Message-ID: <20190516082542.460aad54@hermes.lan> (raw)
In-Reply-To: <20190516114658.29102-1-jgrajcia@cisco.com>

On Thu, 16 May 2019 13:46:58 +0200
Jakub Grajciar <jgrajcia@cisco.com> wrote:

> +	/* remote info */
> +	char remote_name[64];			/**< remote app name */
> +	char remote_if_name[64];

Hard coding magic string sizes has future potential for disaster.
Could you at least add a #define.

> +typedef struct __rte_packed {
> +	uint8_t name[MEMIF_NAME_SZ]; /**< Client app name. In this case DPDK version */
> +	memif_version_t min_version; /**< lowest supported memif version */
> +	memif_version_t max_version; /**< highest supported memif version */
> +	memif_region_index_t max_region; /**< maximum num of regions */
> +	memif_ring_index_t max_m2s_ring; /**< maximum num of M2S ring */
> +	memif_ring_index_t max_s2m_ring; /**< maximum num of S2M rings */
> +	memif_log2_ring_size_t max_log2_ring_size; /**< maximum ring size (as log2) */
> +} memif_msg_hello_t;

Why is name a uint8_t not char? Are end up having to cast it.
Maybe it is because it UTF-8 or you have some subsystem where sizeof(char) != sizeof(uint8_t)?