Re: [PATCH net-next v11 2/4] ethtool: provide customized dim profile management

[Heng Qi <hengqi@linux.alibaba.com>]

On Wed, 1 May 2024 10:36:03 +0800, kernel test robot <lkp@intel.com> wrote:
> Hi Heng,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on net-next/main]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Heng-Qi/linux-dim-move-useful-macros-to-h-file/20240501-013413
> base:   net-next/main
> patch link:    https://lore.kernel.org/r/20240430173136.15807-3-hengqi%40linux.alibaba.com
> patch subject: [PATCH net-next v11 2/4] ethtool: provide customized dim profile management
> config: openrisc-defconfig (https://download.01.org/0day-ci/archive/20240501/202405011004.Rkw6IrSl-lkp@intel.com/config)
> compiler: or1k-linux-gcc (GCC) 13.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240501/202405011004.Rkw6IrSl-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202405011004.Rkw6IrSl-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>    net/ethtool/coalesce.c: In function 'ethnl_update_profile':
>    net/ethtool/coalesce.c:453:46: error: 'struct net_device' has no member named 'irq_moder'
>      453 |         struct dim_irq_moder *irq_moder = dev->irq_moder;
>          |                                              ^~
>    net/ethtool/coalesce.c: At top level:
> >> net/ethtool/coalesce.c:446:12: warning: 'ethnl_update_profile' defined but not used [-Wunused-function]
>      446 | static int ethnl_update_profile(struct net_device *dev,
>          |            ^~~~~~~~~~~~~~~~~~~~
> >> net/ethtool/coalesce.c:151:12: warning: 'coalesce_put_profile' defined but not used [-Wunused-function]
>      151 | static int coalesce_put_profile(struct sk_buff *skb, u16 attr_type,
>          |            ^~~~~~~~~~~~~~~~~~~~
> 

This is a known minor issue, to reduce the use of 'IS_ENABLED(CONFIG_DIMLIB)'
mentioned in v10. Since the calls of ethnl_update_profile() and
coalesce_put_profile() will only occur when IS_ENABLED(CONFIG_DIMLIB) returns
true, the robot's warning can be ignored the code is safe.

All NIPA test cases running on my local pass successfully on V11.

Alternatively, I remake the series to have IS_ENABLED(CONFIG_DIMLIB) back,
up to Kuba (and others). :)

Thanks.

> 
> vim +/ethnl_update_profile +446 net/ethtool/coalesce.c
> 
>    424	
>    425	/**
>    426	 * ethnl_update_profile - get a profile nest with child nests from userspace.
>    427	 * @dev: netdevice to update the profile
>    428	 * @dst: profile get from the driver and modified by ethnl_update_profile.
>    429	 * @nests: nest attr ETHTOOL_A_COALESCE_*X_PROFILE to set profile.
>    430	 * @extack: Netlink extended ack
>    431	 *
>    432	 * Layout of nests:
>    433	 *   Nested ETHTOOL_A_COALESCE_*X_PROFILE attr
>    434	 *     Nested ETHTOOL_A_PROFILE_IRQ_MODERATION attr
>    435	 *       ETHTOOL_A_IRQ_MODERATION_USEC attr
>    436	 *       ETHTOOL_A_IRQ_MODERATION_PKTS attr
>    437	 *       ETHTOOL_A_IRQ_MODERATION_COMPS attr
>    438	 *     ...
>    439	 *     Nested ETHTOOL_A_PROFILE_IRQ_MODERATION attr
>    440	 *       ETHTOOL_A_IRQ_MODERATION_USEC attr
>    441	 *       ETHTOOL_A_IRQ_MODERATION_PKTS attr
>    442	 *       ETHTOOL_A_IRQ_MODERATION_COMPS attr
>    443	 *
>    444	 * Return: 0 on success or a negative error code.
>    445	 */
>  > 446	static int ethnl_update_profile(struct net_device *dev,
>    447					struct dim_cq_moder __rcu **dst,
>    448					const struct nlattr *nests,
>    449					struct netlink_ext_ack *extack)
>    450	{
>    451		int len_irq_moder = ARRAY_SIZE(coalesce_irq_moderation_policy);
>    452		struct nlattr *tb[ARRAY_SIZE(coalesce_irq_moderation_policy)];
>  > 453		struct dim_irq_moder *irq_moder = dev->irq_moder;
>    454		struct dim_cq_moder *new_profile, *old_profile;
>    455		int ret, rem, i = 0, len;
>    456		struct nlattr *nest;
>    457	
>    458		if (!nests)
>    459			return 0;
>    460	
>    461		if (!*dst)
>    462			return -EOPNOTSUPP;
>    463	
>    464		old_profile = rtnl_dereference(*dst);
>    465		len = NET_DIM_PARAMS_NUM_PROFILES * sizeof(*old_profile);
>    466		new_profile = kmemdup(old_profile, len, GFP_KERNEL);
>    467		if (!new_profile)
>    468			return -ENOMEM;
>    469	
>    470		nla_for_each_nested_type(nest, ETHTOOL_A_PROFILE_IRQ_MODERATION,
>    471					 nests, rem) {
>    472			ret = nla_parse_nested(tb, len_irq_moder - 1, nest,
>    473					       coalesce_irq_moderation_policy,
>    474					       extack);
>    475			if (ret)
>    476				goto err_out;
>    477	
>    478			ret = ethnl_update_irq_moder(irq_moder, &new_profile[i].usec,
>    479						     ETHTOOL_A_IRQ_MODERATION_USEC,
>    480						     tb, DIM_COALESCE_USEC,
>    481						     extack);
>    482			if (ret)
>    483				goto err_out;
>    484	
>    485			ret = ethnl_update_irq_moder(irq_moder, &new_profile[i].pkts,
>    486						     ETHTOOL_A_IRQ_MODERATION_PKTS,
>    487						     tb, DIM_COALESCE_PKTS,
>    488						     extack);
>    489			if (ret)
>    490				goto err_out;
>    491	
>    492			ret = ethnl_update_irq_moder(irq_moder, &new_profile[i].comps,
>    493						     ETHTOOL_A_IRQ_MODERATION_COMPS,
>    494						     tb, DIM_COALESCE_COMPS,
>    495						     extack);
>    496			if (ret)
>    497				goto err_out;
>    498	
>    499			i++;
>    500		}
>    501	
>    502		rcu_assign_pointer(*dst, new_profile);
>    503		kfree_rcu(old_profile, rcu);
>    504	
>    505		return 0;
>    506	
>    507	err_out:
>    508		kfree(new_profile);
>    509		return ret;
>    510	}
>    511	
> 
> -- 
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki