Subject: Re: [PATCH net-next 4/6] ice: remove null checks before devm_kfree() calls

From: Maciej Fijalkowski <[email-masked]>
Date: Fri, 23 Jun 2023 12:23:07 +0200

On Thu, Jun 22, 2023 at 11:35:59AM -0700, Tony Nguyen wrote:
> From: Przemek Kitszel <[email-masked]>
> 
> We all know they are redundant.

Przemek,

Ok, they are redundant, but could you also audit the driver if these devm_
allocations could become a plain kzalloc/kfree calls?

> 
> Reviewed-by: Michal Swiatkowski <[email-masked]>
> Reviewed-by: Michal Wilczynski <[email-masked]>
> Reviewed-by: Simon Horman <[email-masked]>
> Signed-off-by: Przemek Kitszel <[email-masked]>
> Tested-by: Arpana Arland <[email-masked]> (A Contingent worker at Intel)
> Signed-off-by: Tony Nguyen <[email-masked]>
> ---
>  drivers/net/ethernet/intel/ice/ice_common.c   |  6 +--
>  drivers/net/ethernet/intel/ice/ice_controlq.c |  3 +-
>  drivers/net/ethernet/intel/ice/ice_flow.c     | 23 ++--------
>  drivers/net/ethernet/intel/ice/ice_lib.c      | 42 +++++++------------
>  drivers/net/ethernet/intel/ice/ice_sched.c    | 11 ++---
>  drivers/net/ethernet/intel/ice/ice_switch.c   | 19 +++------
>  6 files changed, 29 insertions(+), 75 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_common.c b/drivers/net/ethernet/intel/ice/ice_common.c
> index eb2dc0983776..6acb40f3c202 100644
> --- a/drivers/net/ethernet/intel/ice/ice_common.c
> +++ b/drivers/net/ethernet/intel/ice/ice_common.c
> @@ -814,8 +814,7 @@ static void ice_cleanup_fltr_mgmt_struct(struct ice_hw *hw)
>  				devm_kfree(ice_hw_to_dev(hw), lst_itr);
>  			}
>  		}
> -		if (recps[i].root_buf)
> -			devm_kfree(ice_hw_to_dev(hw), recps[i].root_buf);
> +		devm_kfree(ice_hw_to_dev(hw), recps[i].root_buf);
>  	}
>  	ice_rm_all_sw_replay_rule_info(hw);
>  	devm_kfree(ice_hw_to_dev(hw), sw->recp_list);
> @@ -1011,8 +1010,7 @@ static int ice_cfg_fw_log(struct ice_hw *hw, bool enable)
>  	}
>  
>  out:
> -	if (data)
> -		devm_kfree(ice_hw_to_dev(hw), data);
> +	devm_kfree(ice_hw_to_dev(hw), data);
>  
>  	return status;
>  }
> diff --git a/drivers/net/ethernet/intel/ice/ice_controlq.c b/drivers/net/ethernet/intel/ice/ice_controlq.c
> index 385fd88831db..e7d2474c431c 100644
> --- a/drivers/net/ethernet/intel/ice/ice_controlq.c
> +++ b/drivers/net/ethernet/intel/ice/ice_controlq.c
> @@ -339,8 +339,7 @@ do {									\
>  		}							\
>  	}								\
>  	/* free the buffer info list */					\
> -	if ((qi)->ring.cmd_buf)						\
> -		devm_kfree(ice_hw_to_dev(hw), (qi)->ring.cmd_buf);	\
> +	devm_kfree(ice_hw_to_dev(hw), (qi)->ring.cmd_buf);		\
>  	/* free DMA head */						\
>  	devm_kfree(ice_hw_to_dev(hw), (qi)->ring.dma_head);		\
>  } while (0)
> diff --git a/drivers/net/ethernet/intel/ice/ice_flow.c b/drivers/net/ethernet/intel/ice/ice_flow.c
> index ef103e47a8dc..85cca572c22a 100644
> --- a/drivers/net/ethernet/intel/ice/ice_flow.c
> +++ b/drivers/net/ethernet/intel/ice/ice_flow.c
> @@ -1303,23 +1303,6 @@ ice_flow_find_prof_id(struct ice_hw *hw, enum ice_block blk, u64 prof_id)
>  	return NULL;
>  }
>  
> -/**
> - * ice_dealloc_flow_entry - Deallocate flow entry memory
> - * @hw: pointer to the HW struct
> - * @entry: flow entry to be removed
> - */
> -static void
> -ice_dealloc_flow_entry(struct ice_hw *hw, struct ice_flow_entry *entry)
> -{
> -	if (!entry)
> -		return;
> -
> -	if (entry->entry)
> -		devm_kfree(ice_hw_to_dev(hw), entry->entry);
> -
> -	devm_kfree(ice_hw_to_dev(hw), entry);
> -}
> -
>  /**
>   * ice_flow_rem_entry_sync - Remove a flow entry
>   * @hw: pointer to the HW struct
> @@ -1335,7 +1318,8 @@ ice_flow_rem_entry_sync(struct ice_hw *hw, enum ice_block __always_unused blk,
>  
>  	list_del(&entry->l_entry);
>  
> -	ice_dealloc_flow_entry(hw, entry);
> +	devm_kfree(ice_hw_to_dev(hw), entry->entry);
> +	devm_kfree(ice_hw_to_dev(hw), entry);
>  
>  	return 0;
>  }
> @@ -1662,8 +1646,7 @@ ice_flow_add_entry(struct ice_hw *hw, enum ice_block blk, u64 prof_id,
>  
>  out:
>  	if (status && e) {
> -		if (e->entry)
> -			devm_kfree(ice_hw_to_dev(hw), e->entry);
> +		devm_kfree(ice_hw_to_dev(hw), e->entry);
>  		devm_kfree(ice_hw_to_dev(hw), e);
>  	}
>  
> diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
> index 5ddb95d1073a..00e3afd507a4 100644
> --- a/drivers/net/ethernet/intel/ice/ice_lib.c
> +++ b/drivers/net/ethernet/intel/ice/ice_lib.c
> @@ -321,31 +321,19 @@ static void ice_vsi_free_arrays(struct ice_vsi *vsi)
>  
>  	dev = ice_pf_to_dev(pf);
>  
> -	if (vsi->af_xdp_zc_qps) {
> -		bitmap_free(vsi->af_xdp_zc_qps);
> -		vsi->af_xdp_zc_qps = NULL;
> -	}
> +	bitmap_free(vsi->af_xdp_zc_qps);
> +	vsi->af_xdp_zc_qps = NULL;
>  	/* free the ring and vector containers */
> -	if (vsi->q_vectors) {
> -		devm_kfree(dev, vsi->q_vectors);
> -		vsi->q_vectors = NULL;
> -	}
> -	if (vsi->tx_rings) {
> -		devm_kfree(dev, vsi->tx_rings);
> -		vsi->tx_rings = NULL;
> -	}
> -	if (vsi->rx_rings) {
> -		devm_kfree(dev, vsi->rx_rings);
> -		vsi->rx_rings = NULL;
> -	}
> -	if (vsi->txq_map) {
> -		devm_kfree(dev, vsi->txq_map);
> -		vsi->txq_map = NULL;
> -	}
> -	if (vsi->rxq_map) {
> -		devm_kfree(dev, vsi->rxq_map);
> -		vsi->rxq_map = NULL;
> -	}
> +	devm_kfree(dev, vsi->q_vectors);
> +	vsi->q_vectors = NULL;
> +	devm_kfree(dev, vsi->tx_rings);
> +	vsi->tx_rings = NULL;
> +	devm_kfree(dev, vsi->rx_rings);
> +	vsi->rx_rings = NULL;
> +	devm_kfree(dev, vsi->txq_map);
> +	vsi->txq_map = NULL;
> +	devm_kfree(dev, vsi->rxq_map);
> +	vsi->rxq_map = NULL;
>  }
>  
>  /**
> @@ -902,10 +890,8 @@ static void ice_rss_clean(struct ice_vsi *vsi)
>  
>  	dev = ice_pf_to_dev(pf);
>  
> -	if (vsi->rss_hkey_user)
> -		devm_kfree(dev, vsi->rss_hkey_user);
> -	if (vsi->rss_lut_user)
> -		devm_kfree(dev, vsi->rss_lut_user);
> +	devm_kfree(dev, vsi->rss_hkey_user);
> +	devm_kfree(dev, vsi->rss_lut_user);
>  
>  	ice_vsi_clean_rss_flow_fld(vsi);
>  	/* remove RSS replay list */
> diff --git a/drivers/net/ethernet/intel/ice/ice_sched.c b/drivers/net/ethernet/intel/ice/ice_sched.c
> index b7682de0ae05..b664d60fd037 100644
> --- a/drivers/net/ethernet/intel/ice/ice_sched.c
> +++ b/drivers/net/ethernet/intel/ice/ice_sched.c
> @@ -358,10 +358,7 @@ void ice_free_sched_node(struct ice_port_info *pi, struct ice_sched_node *node)
>  				node->sibling;
>  	}
>  
> -	/* leaf nodes have no children */
> -	if (node->children)
> -		devm_kfree(ice_hw_to_dev(hw), node->children);
> -
> +	devm_kfree(ice_hw_to_dev(hw), node->children);
>  	kfree(node->name);
>  	xa_erase(&pi->sched_node_ids, node->id);
>  	devm_kfree(ice_hw_to_dev(hw), node);
> @@ -859,10 +856,8 @@ void ice_sched_cleanup_all(struct ice_hw *hw)
>  	if (!hw)
>  		return;
>  
> -	if (hw->layer_info) {
> -		devm_kfree(ice_hw_to_dev(hw), hw->layer_info);
> -		hw->layer_info = NULL;
> -	}
> +	devm_kfree(ice_hw_to_dev(hw), hw->layer_info);
> +	hw->layer_info = NULL;
>  
>  	ice_sched_clear_port(hw->port_info);
>  
> diff --git a/drivers/net/ethernet/intel/ice/ice_switch.c b/drivers/net/ethernet/intel/ice/ice_switch.c
> index 2ea9e1ae5517..6db4ca7978cb 100644
> --- a/drivers/net/ethernet/intel/ice/ice_switch.c
> +++ b/drivers/net/ethernet/intel/ice/ice_switch.c
> @@ -1636,21 +1636,16 @@ ice_save_vsi_ctx(struct ice_hw *hw, u16 vsi_handle, struct ice_vsi_ctx *vsi)
>   */
>  static void ice_clear_vsi_q_ctx(struct ice_hw *hw, u16 vsi_handle)
>  {
> -	struct ice_vsi_ctx *vsi;
> +	struct ice_vsi_ctx *vsi = ice_get_vsi_ctx(hw, vsi_handle);
>  	u8 i;
>  
> -	vsi = ice_get_vsi_ctx(hw, vsi_handle);
>  	if (!vsi)
>  		return;
>  	ice_for_each_traffic_class(i) {
> -		if (vsi->lan_q_ctx[i]) {
> -			devm_kfree(ice_hw_to_dev(hw), vsi->lan_q_ctx[i]);
> -			vsi->lan_q_ctx[i] = NULL;
> -		}
> -		if (vsi->rdma_q_ctx[i]) {
> -			devm_kfree(ice_hw_to_dev(hw), vsi->rdma_q_ctx[i]);
> -			vsi->rdma_q_ctx[i] = NULL;
> -		}
> +		devm_kfree(ice_hw_to_dev(hw), vsi->lan_q_ctx[i]);
> +		vsi->lan_q_ctx[i] = NULL;
> +		devm_kfree(ice_hw_to_dev(hw), vsi->rdma_q_ctx[i]);
> +		vsi->rdma_q_ctx[i] = NULL;
>  	}
>  }
>  
> @@ -5468,9 +5463,7 @@ ice_add_adv_recipe(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  		devm_kfree(ice_hw_to_dev(hw), fvit);
>  	}
>  
> -	if (rm->root_buf)
> -		devm_kfree(ice_hw_to_dev(hw), rm->root_buf);
> -
> +	devm_kfree(ice_hw_to_dev(hw), rm->root_buf);
>  	kfree(rm);
>  
>  err_free_lkup_exts:
> -- 
> 2.38.1
> 
>