[hnaz-mm:master 343/435] arch/riscv/lib/delay.c:77:17: error: implicit declaration of function 'cpu_relax'

[kernel test robot]

tree:   https://github.com/hnaz/linux-mm master
head:   b8280145cf2a894c873fdf91fb2af474c52ac6cc
commit: eaadd3a1784064254eb06b36fbd4b653f0228478 [343/435] include/linux/delay.h: replace kernel.h with the necessary inclusions
config: riscv-allyesconfig (attached as .config)
compiler: riscv64-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/hnaz/linux-mm/commit/eaadd3a1784064254eb06b36fbd4b653f0228478
        git remote add hnaz-mm https://github.com/hnaz/linux-mm
        git fetch --no-tags hnaz-mm master
        git checkout eaadd3a1784064254eb06b36fbd4b653f0228478
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=riscv 

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

All errors (new ones prefixed by >>):

   arch/riscv/lib/delay.c: In function '__delay':
>> arch/riscv/lib/delay.c:77:17: error: implicit declaration of function 'cpu_relax' [-Werror=implicit-function-declaration]
      77 |                 cpu_relax();
         |                 ^~~~~~~~~
   cc1: all warnings being treated as errors


vim +/cpu_relax +77 arch/riscv/lib/delay.c

6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  71  
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  72  void __delay(unsigned long cycles)
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  73  {
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  74  	u64 t0 = get_cycles();
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  75  
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  76  	while ((unsigned long)(get_cycles() - t0) < cycles)
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10 @77  		cpu_relax();
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  78  }
24948b7ec0f31d3 Olof Johansson 2017-11-29  79  EXPORT_SYMBOL(__delay);
6d60b6ee0c9777b Palmer Dabbelt 2017-07-10  80  

:::::: The code at line 77 was first introduced by commit
:::::: 6d60b6ee0c9777b92c47f6dc8aad1dd90612e4fa RISC-V: Device, timer, IRQs, and the SBI

:::::: TO: Palmer Dabbelt <palmer@xxxxxxxxxxx>
:::::: CC: Palmer Dabbelt <palmer@xxxxxxxxxxx>

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

Attachment: .config.gz
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