Re: [dpdk-dev] [PATCH v2 2/5] net/hns3: use unsigned types for bit operator

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 11/6/2020 3:51 AM, Lijun Ou wrote:
> From: Hongbo Zheng <zhenghongbo3@huawei.com>
> 
> According to bit operator reliability style, variables in
> the right expression participating int bit operation
> cannot be of unsigned type.

Assuming this is talking about BIT() ("#define BIT(nr) (1UL << (nr))"),
is this description says, in the "a << b", 'b' can't be unsigned?

The code below does the opposite, "int i" -> "uint32_t i", even though there is 
a typo in above description, why 'b' can't be signed?
It can't be negative, but not sure if is it a problem to have it signed.


Also only first change in this patch seems related to the patch title and the 
description, rest looks related to signed / unsigned comparison fixes, if so can 
you separate them into their patch with proper description please?

> 
> Signed-off-by: Hongbo Zheng <zhenghongbo3@huawei.com>
> Signed-off-by: Lijun Ou <oulijun@huawei.com>
> ---
>   drivers/net/hns3/hns3_ethdev_vf.c     |  2 +-
>   drivers/net/hns3/hns3_rxtx_vec_neon.h | 11 +++++------
>   2 files changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/hns3/hns3_ethdev_vf.c b/drivers/net/hns3/hns3_ethdev_vf.c
> index 6f71cd6..2e9bfda 100644
> --- a/drivers/net/hns3/hns3_ethdev_vf.c
> +++ b/drivers/net/hns3/hns3_ethdev_vf.c
> @@ -1331,7 +1331,7 @@ hns3vf_get_tc_info(struct hns3_hw *hw)
>   {
>   	uint8_t resp_msg;
>   	int ret;
> -	int i;
> +	uint32_t i;
>   
>   	ret = hns3_send_mbx_msg(hw, HNS3_MBX_GET_TCINFO, 0, NULL, 0,
>   				true, &resp_msg, sizeof(resp_msg));
> diff --git a/drivers/net/hns3/hns3_rxtx_vec_neon.h b/drivers/net/hns3/hns3_rxtx_vec_neon.h
> index 8d7721b..fe525de 100644
> --- a/drivers/net/hns3/hns3_rxtx_vec_neon.h
> +++ b/drivers/net/hns3/hns3_rxtx_vec_neon.h
> @@ -89,13 +89,12 @@ hns3_desc_parse_field(struct hns3_rx_queue *rxq,
>   		      struct hns3_desc *rxdp,
>   		      uint32_t   bd_vld_num)
>   {
> -	uint32_t l234_info, ol_info, bd_base_info;
> +	uint32_t l234_info, ol_info, bd_base_info, cksum_err, i;

Not sure combining more variable declarations into same line is good idea, why 
not have their own lines?

>   	struct rte_mbuf *pkt;
>   	uint32_t retcode = 0;
> -	uint32_t cksum_err;
> -	int ret, i;
> +	int ret;
>   
> -	for (i = 0; i < (int)bd_vld_num; i++) {
> +	for (i = 0; i < bd_vld_num; i++) {
>   		pkt = sw_ring[i].mbuf;
>   
>   		/* init rte_mbuf.rearm_data last 64-bit */
> @@ -129,9 +128,9 @@ hns3_recv_burst_vec(struct hns3_rx_queue *__restrict rxq,
>   	uint16_t rx_id = rxq->next_to_use;
>   	struct hns3_entry *sw_ring = &rxq->sw_ring[rx_id];
>   	struct hns3_desc *rxdp = &rxq->rx_ring[rx_id];
> -	uint32_t bd_valid_num, parse_retcode;
> +	uint32_t bd_valid_num, parse_retcode, pos;
>   	uint16_t nb_rx = 0;
> -	int pos, offset;
> +	int offset;
>   
>   	/* mask to shuffle from desc to mbuf's rx_descriptor_fields1 */
>   	uint8x16_t shuf_desc_fields_msk = {
>