Hi Zhang, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on next-20220527] [cannot apply to akpm-mm/mm-everything arm64/for-next/core s390/features tip/x86/core v5.18] [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/intel-lab-lkp/linux/commits/Zhang-Yuchen/procfs-add-syscall-statistics/20220527-191241 base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 7e284070abe53d448517b80493863595af4ab5f0 config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20220527/202205272216.w7dE4biW-lkp@xxxxxxxxx/config) compiler: arceb-elf-gcc (GCC) 11.3.0 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/979bf5b1b085588caab1cbdce55e40e823c12db9 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Zhang-Yuchen/procfs-add-syscall-statistics/20220527-191241 git checkout 979bf5b1b085588caab1cbdce55e40e823c12db9 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=arc SHELL=/bin/bash fs/proc/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> fs/proc/syscall.c:13:5: warning: no previous prototype for 'show_syscalls' [-Wmissing-prototypes] 13 | int show_syscalls(struct seq_file *p, void *v) | ^~~~~~~~~~~~~ vim +/show_syscalls +13 fs/proc/syscall.c 12 > 13 int show_syscalls(struct seq_file *p, void *v) 14 { 15 int i = *(loff_t *)v, j; 16 static int prec; 17 const char *syscall_name = get_syscall_name(i); 18 19 if (i > NR_syscalls) 20 return 0; 21 22 /* print header and calculate the width of the first column */ 23 if (i == 0) { 24 for (prec = 3, j = 1000; prec < 10 && j <= NR_syscalls; ++prec) 25 j *= 10; 26 seq_printf(p, "%*s", prec + 8, ""); 27 for_each_online_cpu(j) 28 seq_printf(p, "CPU%-8d", j); 29 seq_putc(p, '\n'); 30 } 31 32 if (syscall_name == NULL) 33 return 0; 34 35 seq_printf(p, "%*d: ", prec, i); 36 for_each_online_cpu(j) 37 seq_printf(p, "%10llu ", 38 per_cpu(__per_cpu_syscall_count, j)[i]); 39 seq_printf(p, " %s", syscall_name); 40 seq_putc(p, '\n'); 41 42 return 0; 43 } 44 -- 0-DAY CI Kernel Test Service https://01.org/lkp