Re: [dpdk-dev] [PATCH] net/mlx5: fix modify header action position

[Ori Kam <orika@mellanox.com>]

PSB

> -----Original Message-----
> From: Yongseok Koh
> Sent: Wednesday, April 17, 2019 2:42 AM
> To: Ori Kam <orika@mellanox.com>
> Cc: Shahaf Shuler <shahafs@mellanox.com>; dev@dpdk.org; Dekel Peled
> <dekelp@mellanox.com>; stable@dpdk.org
> Subject: Re: [PATCH] net/mlx5: fix modify header action position
> 
> On Sun, Apr 14, 2019 at 08:19:57PM +0000, Ori Kam wrote:
> > According to RTE flow the action order should be the order that the
> > actions were given.
> > In the case of modify actions the position of the action was always
> > last.
> >
> > This commit solves this issue by saving the position of the first modify
> > action, and then adds to this position the pointer to the modify action.
> >
> > Fixes: 4bb14c83df95 ("net/mlx5: support modify header using Direct Verbs")
> > Cc: dekelp@mellanox.com
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Ori Kam <orika@mellanox.com>
> > ---
> >  drivers/net/mlx5/mlx5_flow_dv.c | 15 ++++++++++++++-
> >  1 file changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/mlx5/mlx5_flow_dv.c
> b/drivers/net/mlx5/mlx5_flow_dv.c
> > index 3862b26..7b5eab7 100644
> > --- a/drivers/net/mlx5/mlx5_flow_dv.c
> > +++ b/drivers/net/mlx5/mlx5_flow_dv.c
> > @@ -3235,6 +3235,7 @@ struct field_modify_info modify_tcp[] = {
> >  	};
> >  	union flow_dv_attr flow_attr = { .attr = 0 };
> >  	struct mlx5_flow_dv_tag_resource tag_resource;
> > +	uint32_t modify_action_position = UINT32_MAX;
> 
> How about modify_action_idx and setting negative value as invalid? I don't
> force
> it but it is just your choice.
> 

That was my first thought, but it gave warning when int is used as index to array.

> 	int modify_action_idx = -1;
> 
> >  	if (priority == MLX5_FLOW_PRIO_RSVD)
> >  		priority = priv->config.flow_prio - 1;
> > @@ -3419,6 +3420,8 @@ struct field_modify_info modify_tcp[] = {
> >
> 	RTE_FLOW_ACTION_TYPE_SET_MAC_SRC ?
> >  					MLX5_FLOW_ACTION_SET_MAC_SRC
> :
> >  					MLX5_FLOW_ACTION_SET_MAC_DST;
> > +			if (modify_action_position == UINT32_MAX)
> > +				modify_action_position = actions_n++;
> 
> Even though this does right thing, I hope it to be neater. Same lines are
> repeating before 'break', so you can move it just out of this switch-case.
> For example,
> 
> 	for(..) {
> 		switch(..) {
> 		case ..
> 		default:
> 			break;
> 		}
> 		/* Check if a modify action is firstly seen. */
> 		if (modify_action_idx < 0 &&
> 		    (action_flags & MLX5_FLOW_MODIFY_HDR_ACTIONS))
> 			modify_action_idx = actions_n++;
> 	}
> 
> thanks,
> Yongseok
> 

I like your idea, will change.

> >  			break;
> >  		case RTE_FLOW_ACTION_TYPE_SET_IPV4_SRC:
> >  		case RTE_FLOW_ACTION_TYPE_SET_IPV4_DST:
> > @@ -3429,6 +3432,8 @@ struct field_modify_info modify_tcp[] = {
> >
> 	RTE_FLOW_ACTION_TYPE_SET_IPV4_SRC ?
> >  					MLX5_FLOW_ACTION_SET_IPV4_SRC :
> >  					MLX5_FLOW_ACTION_SET_IPV4_DST;
> > +			if (modify_action_position == UINT32_MAX)
> > +				modify_action_position = actions_n++;
> >  			break;
> >  		case RTE_FLOW_ACTION_TYPE_SET_IPV6_SRC:
> >  		case RTE_FLOW_ACTION_TYPE_SET_IPV6_DST:
> > @@ -3439,6 +3444,8 @@ struct field_modify_info modify_tcp[] = {
> >
> 	RTE_FLOW_ACTION_TYPE_SET_IPV6_SRC ?
> >  					MLX5_FLOW_ACTION_SET_IPV6_SRC :
> >  					MLX5_FLOW_ACTION_SET_IPV6_DST;
> > +			if (modify_action_position == UINT32_MAX)
> > +				modify_action_position = actions_n++;
> >  			break;
> >  		case RTE_FLOW_ACTION_TYPE_SET_TP_SRC:
> >  		case RTE_FLOW_ACTION_TYPE_SET_TP_DST:
> > @@ -3450,6 +3457,8 @@ struct field_modify_info modify_tcp[] = {
> >
> 	RTE_FLOW_ACTION_TYPE_SET_TP_SRC ?
> >  					MLX5_FLOW_ACTION_SET_TP_SRC :
> >  					MLX5_FLOW_ACTION_SET_TP_DST;
> > +			if (modify_action_position == UINT32_MAX)
> > +				modify_action_position = actions_n++;
> >  			break;
> >  		case RTE_FLOW_ACTION_TYPE_DEC_TTL:
> >  			if (flow_dv_convert_action_modify_dec_ttl(&res,
> items,
> > @@ -3457,6 +3466,8 @@ struct field_modify_info modify_tcp[] = {
> >  								  error))
> >  				return -rte_errno;
> >  			action_flags |= MLX5_FLOW_ACTION_DEC_TTL;
> > +			if (modify_action_position == UINT32_MAX)
> > +				modify_action_position = actions_n++;
> >  			break;
> >  		case RTE_FLOW_ACTION_TYPE_SET_TTL:
> >  			if (flow_dv_convert_action_modify_ttl(&res, actions,
> > @@ -3464,6 +3475,8 @@ struct field_modify_info modify_tcp[] = {
> >  							     error))
> >  				return -rte_errno;
> >  			action_flags |= MLX5_FLOW_ACTION_SET_TTL;
> > +			if (modify_action_position == UINT32_MAX)
> > +				modify_action_position = actions_n++;
> >  			break;
> >  		case RTE_FLOW_ACTION_TYPE_END:
> >  			actions_end = true;
> > @@ -3474,7 +3487,7 @@ struct field_modify_info modify_tcp[] = {
> >  								 dev_flow,
> >  								 error))
> >  					return -rte_errno;
> > -				dev_flow->dv.actions[actions_n++] =
> > +				dev_flow->dv.actions[modify_action_position]
> =
> >  					dev_flow->dv.modify_hdr-
> >verbs_action;
> >  			}
> >  			break;
> > --
> > 1.8.3.1
> >