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

From: Przemek Kitszel <[email-masked]>
Date: Fri, 23 Jun 2023 12:44:29 +0200

On 6/23/23 12:23, Maciej Fijalkowski wrote:
> 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?

Olek was also motivating such audit :)

I have some cases collected with intention to send in bulk for next 
window, list is not exhaustive though.

> 
>>
>> 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
>>
>>