Re: [PATCH bpf-next v1 8/9] bpf: Introduce cgroup iter

[kernel test robot <lkp@intel.com>]

Hi Hao,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Hao-Luo/Extend-cgroup-interface-with-bpf/20220226-074615
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: arm-randconfig-c002-20220226 (https://download.01.org/0day-ci/archive/20220226/202202261033.JZXn2oS0-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 11.2.0
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
        # https://github.com/0day-ci/linux/commit/ee74423719e2efb4efa7a4491920c78b60024ec7
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Hao-Luo/Extend-cgroup-interface-with-bpf/20220226-074615
        git checkout ee74423719e2efb4efa7a4491920c78b60024ec7
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arm SHELL=/bin/bash kernel/bpf/

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 >>):

>> kernel/bpf/cgroup_iter.c:101:6: warning: no previous prototype for 'bpf_iter_cgroup_show_fdinfo' [-Wmissing-prototypes]
     101 | void bpf_iter_cgroup_show_fdinfo(const struct bpf_iter_aux_info *aux,
         |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
   kernel/bpf/cgroup_iter.c: In function 'bpf_iter_cgroup_show_fdinfo':
>> kernel/bpf/cgroup_iter.c:107:40: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'u64' {aka 'long long unsigned int'} [-Wformat=]
     107 |         seq_printf(seq, "cgroup_id:\t%lu\n", aux->cgroup_id);
         |                                      ~~^     ~~~~~~~~~~~~~~
         |                                        |        |
         |                                        |        u64 {aka long long unsigned int}
         |                                        long unsigned int
         |                                      %llu
   kernel/bpf/cgroup_iter.c: At top level:
>> kernel/bpf/cgroup_iter.c:111:5: warning: no previous prototype for 'bpf_iter_cgroup_fill_link_info' [-Wmissing-prototypes]
     111 | int bpf_iter_cgroup_fill_link_info(const struct bpf_iter_aux_info *aux,
         |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


vim +/bpf_iter_cgroup_show_fdinfo +101 kernel/bpf/cgroup_iter.c

   100	
 > 101	void bpf_iter_cgroup_show_fdinfo(const struct bpf_iter_aux_info *aux,
   102					 struct seq_file *seq)
   103	{
   104		char buf[64] = {0};
   105	
   106		cgroup_path_from_kernfs_id(aux->cgroup_id, buf, sizeof(buf));
 > 107		seq_printf(seq, "cgroup_id:\t%lu\n", aux->cgroup_id);
   108		seq_printf(seq, "cgroup_path:\t%s\n", buf);
   109	}
   110	
 > 111	int bpf_iter_cgroup_fill_link_info(const struct bpf_iter_aux_info *aux,
   112					   struct bpf_link_info *info)
   113	{
   114		info->iter.cgroup.cgroup_id = aux->cgroup_id;
   115		return 0;
   116	}
   117	

---
0-DAY CI Kernel Test Service, Intel Corporation
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