Hi tangmeng, Thank you for the patch! Yet something to improve: [auto build test ERROR on tip/timers/core] [also build test ERROR on linus/master kees/for-next/pstore v5.17-rc2 next-20220131] [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] url: https://github.com/0day-ci/linux/commits/tangmeng/kernel-time-move-timer-sysctls-to-its-own-file/20220131-182433 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 35e13e9da9afbce13c1d36465504ece4e65f24fe config: arc-randconfig-r043-20220131 (https://download.01.org/0day-ci/archive/20220201/202202012049.OHxc9ybu-lkp@xxxxxxxxx/config) compiler: arc-elf-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/c54967d83b26ebacf4a1b686c6b659150b73306c git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review tangmeng/kernel-time-move-timer-sysctls-to-its-own-file/20220131-182433 git checkout c54967d83b26ebacf4a1b686c6b659150b73306c # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash kernel/time/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): kernel/time/timer.c: In function 'timer_sysctl_init': >> kernel/time/timer.c:284:9: error: implicit declaration of function 'register_sysctl_init'; did you mean 'timer_sysctl_init'? [-Werror=implicit-function-declaration] 284 | register_sysctl_init("kernel", timer_sysctl); | ^~~~~~~~~~~~~~~~~~~~ | timer_sysctl_init In file included from include/linux/perf_event.h:25, from include/linux/trace_events.h:10, from include/trace/syscall.h:7, from include/linux/syscalls.h:88, from kernel/time/timer.c:35: At top level: arch/arc/include/asm/perf_event.h:126:27: warning: 'arc_pmu_cache_map' defined but not used [-Wunused-const-variable=] 126 | static const unsigned int arc_pmu_cache_map[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = { | ^~~~~~~~~~~~~~~~~ arch/arc/include/asm/perf_event.h:91:27: warning: 'arc_pmu_ev_hw_map' defined but not used [-Wunused-const-variable=] 91 | static const char * const arc_pmu_ev_hw_map[] = { | ^~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +284 kernel/time/timer.c 281 282 static int __init timer_sysctl_init(void) 283 { > 284 register_sysctl_init("kernel", timer_sysctl); 285 return 0; 286 } 287 __initcall(timer_sysctl_init); 288 #endif 289 static inline bool is_timers_nohz_active(void) 290 { 291 return static_branch_unlikely(&timers_nohz_active); 292 } 293 #else 294 static inline bool is_timers_nohz_active(void) { return false; } 295 #endif /* NO_HZ_COMMON */ 296 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx