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/20220130-231458 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 35e13e9da9afbce13c1d36465504ece4e65f24fe config: hexagon-randconfig-r045-20220130 (https://download.01.org/0day-ci/archive/20220131/202201310051.QnG1PthP-lkp@xxxxxxxxx/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project f1c18acb07aa40f42b87b70462a6d1ab77a4825c) 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/40476bc60525c2a3aeffa4af1080bf1c4bfb8f10 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/20220130-231458 git checkout 40476bc60525c2a3aeffa4af1080bf1c4bfb8f10 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon 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:2048:2: error: implicit declaration of function 'timer_sysctl_init' [-Werror,-Wimplicit-function-declaration] timer_sysctl_init(); ^ 1 error generated. vim +/timer_sysctl_init +2048 kernel/time/timer.c 2042 2043 void __init init_timers(void) 2044 { 2045 init_timer_cpus(); 2046 posix_cputimers_init_work(); 2047 open_softirq(TIMER_SOFTIRQ, run_timer_softirq); > 2048 timer_sysctl_init(); 2049 } 2050 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx