Subject: Re: [PATCH] vdpa/mlx5: simplfy error handler in mlx5_vdpa_dev_add()
To:     Eli Cohen <elic@nvidia.com>
Cc:     mst@redhat.com, jasowang@redhat.com, parav@nvidia.com,
        si-wei.liu@oracle.com, xieyongji@bytedance.com,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
References: <20220109132422.4047425-1-trix@redhat.com>
 <20220109141207.GC70879@mtl-vdi-166.wap.labs.mlnx>
From:   Tom Rix <trix@redhat.com>
Message-ID: <26ef040d-8b18-aa65-85ab-6e223c97c39d@redhat.com>
Date:   Sun, 9 Jan 2022 09:02:32 -0800
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On 1/9/22 6:12 AM, Eli Cohen wrote:
> On Sun, Jan 09, 2022 at 05:24:22AM -0800, trix@redhat.com wrote:
>> From: Tom Rix <trix@redhat.com>
>>
>> The use of pfmdev is protected by two calls to is_zero_ether_add().
>> The second call in the error handler can be replaced by
>> checking if pfmdev was set as part of the earlier call.
>>
>> Signed-off-by: Tom Rix <trix@redhat.com>
>> ---
> It's not fixing anything, right?
Correct, or I would have added a Fixes: tag
> Maybe add justification for this change
> by e.g. showing the code size had decreased or so?

Sorry, I thought I had done that.  Generally removing any function call 
is a win and the worst case is a tie.

Tom

>>   drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> index 37220f6db7ad7..2d38b8fe9305e 100644
>> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
>> @@ -2530,7 +2530,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
>>   {
>>   	struct mlx5_vdpa_mgmtdev *mgtdev = container_of(v_mdev, struct mlx5_vdpa_mgmtdev, mgtdev);
>>   	struct virtio_net_config *config;
>> -	struct mlx5_core_dev *pfmdev;
>> +	struct mlx5_core_dev *pfmdev = NULL;
>>   	struct mlx5_vdpa_dev *mvdev;
>>   	struct mlx5_vdpa_net *ndev;
>>   	struct mlx5_core_dev *mdev;
>> @@ -2654,7 +2654,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
>>   err_res:
>>   	mlx5_vdpa_free_resources(&ndev->mvdev);
>>   err_mpfs:
>> -	if (!is_zero_ether_addr(config->mac))
>> +	if (pfmdev)
>>   		mlx5_mpfs_del_mac(pfmdev, config->mac);
>>   err_mtu:
>>   	mutex_destroy(&ndev->reslock);
>> -- 
>> 2.26.3
>>