Hi Wei,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Wei-Wang/implement-kthread-based-napi-poll/20200915-013651
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git e059c6f340f6fccadd3db9993f06d4cc51305804
config: arm64-randconfig-r024-20200914 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project b2c32c90bab09a6e2c1f370429db26017a182143)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> net/core/net-sysfs.c:541:16: warning: no previous prototype for function '__alloc_thread_bitmap' [-Wmissing-prototypes]
   unsigned long *__alloc_thread_bitmap(struct net_device *netdev, int *bits)
                  ^
   net/core/net-sysfs.c:541:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   unsigned long *__alloc_thread_bitmap(struct net_device *netdev, int *bits)
   ^
   static 
   1 warning generated.

# https://github.com/0day-ci/linux/commit/ba7d63f1040aedba86f70713af085d86322fee62
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Wei-Wang/implement-kthread-based-napi-poll/20200915-013651
git checkout ba7d63f1040aedba86f70713af085d86322fee62
vim +/__alloc_thread_bitmap +541 net/core/net-sysfs.c

   540	
 > 541	unsigned long *__alloc_thread_bitmap(struct net_device *netdev, int *bits)
   542	{
   543		struct napi_struct *n;
   544	
   545		*bits = 0;
   546		list_for_each_entry(n, &netdev->napi_list, dev_list)
   547			(*bits)++;
   548	
   549		return kmalloc_array(BITS_TO_LONGS(*bits), sizeof(unsigned long),
   550				     GFP_ATOMIC | __GFP_ZERO);
   551	}
   552	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org