Re: [PATCH v2 bpf-next 2/3] bpf: introduce helper bpf_get_branch_snapshot

[kernel test robot]

Hi Song,

I love your patch! Yet something to improve:

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

url:    https://github.com/0day-ci/linux/commits/Song-Liu/bpf-introduce-bpf_get_branch_snapshot/20210827-061705
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: riscv-randconfig-r023-20210827 (attached as .config)
compiler: riscv32-linux-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/ad355675cf08d95b3f5171b681420cfc8e2f1b7e
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Song-Liu/bpf-introduce-bpf_get_branch_snapshot/20210827-061705
        git checkout ad355675cf08d95b3f5171b681420cfc8e2f1b7e
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash

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

All errors (new ones prefixed by >>):

   riscv32-linux-ld: kernel/bpf/trampoline.o: in function `.L57':
>> trampoline.c:(.text+0x34c): undefined reference to `__SCK__perf_snapshot_branch_stack'
   riscv32-linux-ld: kernel/bpf/trampoline.o: in function `.L61':
   trampoline.c:(.text+0x360): undefined reference to `bpf_perf_branch_snapshot'

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

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