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-rc1 next-20220128] [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/20220128-165225 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 35e13e9da9afbce13c1d36465504ece4e65f24fe config: arm64-randconfig-r026-20220127 (https://download.01.org/0day-ci/archive/20220129/202201290325.Jyor2i8O-lkp@xxxxxxxxx/config) compiler: aarch64-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/8bd44d33085f8ab50523016cbdb0c918dc4b4f3c 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/20220128-165225 git checkout 8bd44d33085f8ab50523016cbdb0c918dc4b4f3c # 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=arm64 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:283:9: error: implicit declaration of function 'register_sysctl_init'; did you mean 'timer_sysctl_init'? [-Werror=implicit-function-declaration] 283 | register_sysctl_init("kerneli/timer", timer_sysctl); | ^~~~~~~~~~~~~~~~~~~~ | timer_sysctl_init cc1: some warnings being treated as errors vim +283 kernel/time/timer.c 280 281 static int __init timer_sysctl_init(void) 282 { > 283 register_sysctl_init("kerneli/timer", timer_sysctl); 284 return 0; 285 } 286 #else 287 #define timer_sysctl_init() do { } while (0) 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