Hi Song,

kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on linus/master v6.4-rc2 next-20230517]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Song-Liu/watchdog-Allow-nmi-watchdog-to-use-ref-cycles-event/20230518-015450
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20230517175105.1614575-1-song%40kernel.org
patch subject: [PATCH v3] watchdog: Allow nmi watchdog to use "ref-cycles" event
config: powerpc-allnoconfig
compiler: powerpc-linux-gcc (GCC) 12.1.0
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/intel-lab-lkp/linux/commit/c119f335899443fe6ba4c91b295b469e2793712f
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Song-Liu/watchdog-Allow-nmi-watchdog-to-use-ref-cycles-event/20230518-015450
        git checkout c119f335899443fe6ba4c91b295b469e2793712f
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/kernel/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202305180440.PKKQNyLU-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from arch/powerpc/kernel/stacktrace.c:15:
>> include/linux/nmi.h:112:13: error: no previous prototype for 'hardlockup_config_perf_event' [-Werror=missing-prototypes]
     112 | extern void hardlockup_config_perf_event(const char *str) { }
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: all warnings being treated as errors


vim +/hardlockup_config_perf_event +112 include/linux/nmi.h

    96	
    97	#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
    98	extern void arch_touch_nmi_watchdog(void);
    99	extern void hardlockup_detector_perf_stop(void);
   100	extern void hardlockup_detector_perf_restart(void);
   101	extern void hardlockup_detector_perf_disable(void);
   102	extern void hardlockup_detector_perf_enable(void);
   103	extern void hardlockup_detector_perf_cleanup(void);
   104	extern int hardlockup_detector_perf_init(void);
   105	extern void hardlockup_config_perf_event(const char *str);
   106	#else
   107	static inline void hardlockup_detector_perf_stop(void) { }
   108	static inline void hardlockup_detector_perf_restart(void) { }
   109	static inline void hardlockup_detector_perf_disable(void) { }
   110	static inline void hardlockup_detector_perf_enable(void) { }
   111	static inline void hardlockup_detector_perf_cleanup(void) { }
 > 112	extern void hardlockup_config_perf_event(const char *str) { }
   113	# if !defined(CONFIG_HAVE_NMI_WATCHDOG)
   114	static inline int hardlockup_detector_perf_init(void) { return -ENODEV; }
   115	static inline void arch_touch_nmi_watchdog(void) {}
   116	# else
   117	static inline int hardlockup_detector_perf_init(void) { return 0; }
   118	# endif
   119	#endif
   120	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki