[rostedt-trace:for-next 58/100] samples/ftrace/ftrace-direct-multi.c:8:6: warning: no previous prototype for function 'my_direct_func'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git for-next
head:   93d76e4a0e0112b320c4f0e2a3930ad634628c58
commit: 5fae941b9a6f95773df644e7cf304bf199707876 [58/100] ftrace/samples: Add multi direct interface test module
config: x86_64-randconfig-r024-20211031 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 82ed106567063ea269c6d5669278b733e173a42f)
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://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git/commit/?id=5fae941b9a6f95773df644e7cf304bf199707876
        git remote add rostedt-trace https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
        git fetch --no-tags rostedt-trace for-next
        git checkout 5fae941b9a6f95773df644e7cf304bf199707876
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=x86_64 

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

All warnings (new ones prefixed by >>):

>> samples/ftrace/ftrace-direct-multi.c:8:6: warning: no previous prototype for function 'my_direct_func' [-Wmissing-prototypes]
   void my_direct_func(unsigned long ip)
        ^
   samples/ftrace/ftrace-direct-multi.c:8:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void my_direct_func(unsigned long ip)
   ^
   static 
   1 warning generated.


vim +/my_direct_func +8 samples/ftrace/ftrace-direct-multi.c

     7	
   > 8	void my_direct_func(unsigned long ip)
     9	{
    10		trace_printk("ip %lx\n", ip);
    11	}
    12	

---
0-DAY CI Kernel Test Service, Intel Corporation
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Attachment: .config.gz
Description: application/gzip