Hi "Björn,

I love your patch! Perhaps something to improve:

[auto build test WARNING on 7b1e385c9a488de9291eaaa412146d3972e9dec5]

url:    https://github.com/0day-ci/linux/commits/Bj-rn-T-pel/Optimize-bpf_redirect_map-xdp_do_redirect/20210219-230349
base:   7b1e385c9a488de9291eaaa412146d3972e9dec5
config: nds32-randconfig-r006-20210219 (attached as .config)
compiler: nds32le-linux-gcc (GCC) 9.3.0
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/e784328ffb3b588155aeee02ff6a96b4a6b7cf20
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Bj-rn-T-pel/Optimize-bpf_redirect_map-xdp_do_redirect/20210219-230349
        git checkout e784328ffb3b588155aeee02ff6a96b4a6b7cf20
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=nds32 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

   In file included from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/hugetlb.h:9,
                    from kernel/events/core.c:31:

quoted

include/linux/bpf.h:1629:42: warning: 'struct bpf_cpu_map_entry' declared inside parameter list will not be visible outside of this definition or declaration

    1629 | static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
         |                                          ^~~~~~~~~~~~~~~~~
   kernel/events/core.c:6539:6: warning: no previous prototype for 'perf_pmu_snapshot_aux' [-Wmissing-prototypes]
    6539 | long perf_pmu_snapshot_aux(struct perf_buffer *rb,
         |      ^~~~~~~~~~~~~~~~~~~~~
--
   In file included from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/perf_event.h:57,
                    from kernel/events/ring_buffer.c:11:

quoted

include/linux/bpf.h:1629:42: warning: 'struct bpf_cpu_map_entry' declared inside parameter list will not be visible outside of this definition or declaration

    1629 | static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
         |                                          ^~~~~~~~~~~~~~~~~


vim +1629 include/linux/bpf.h

9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1628  
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16 @1629  static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1630  				  struct xdp_buff *xdp,
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1631  				  struct net_device *dev_rx)
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1632  {
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1633  	return 0;
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1634  }
040ee69226f8a9 Al Viro                2017-12-02  1635  

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