Hi Zhen, Thank you for the patch! Yet something to improve: [auto build test ERROR on paulmck-rcu/dev] [also build test ERROR on linus/master v6.0-rc1 next-20220817] [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/Zhen-Lei/rcu-nocb-Delete-local-variable-need_rcu_nocb_mask-in-rcu_init_nohz/20220816-205131 base: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev config: hexagon-randconfig-r041-20220818 (https://download.01.org/0day-ci/archive/20220818/202208180940.Jks0rOXz-lkp@xxxxxxxxx/config) compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project aed5e3bea138ce581d682158eb61c27b3cfdd6ec) 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/a1d5079765918764de3ff6e3e63fa2db7f7c14df git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Zhen-Lei/rcu-nocb-Delete-local-variable-need_rcu_nocb_mask-in-rcu_init_nohz/20220816-205131 git checkout a1d5079765918764de3ff6e3e63fa2db7f7c14df # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash kernel/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): In file included from kernel/rcu/tree.c:4801: >> kernel/rcu/tree_nocb.h:1216:10: error: assigning to 'struct cpumask *' from 'const struct cpumask *' discards qualifiers [-Werror,-Wincompatible-pointer-types-discards-qualifiers] cpumask = cpu_possible_mask; ^ ~~~~~~~~~~~~~~~~~ 1 error generated. vim +1216 kernel/rcu/tree_nocb.h 1208 1209 void __init rcu_init_nohz(void) 1210 { 1211 int cpu; 1212 struct rcu_data *rdp; 1213 struct cpumask *cpumask = NULL; 1214 1215 #if defined(CONFIG_RCU_NOCB_CPU_DEFAULT_ALL) > 1216 cpumask = cpu_possible_mask; 1217 #elif defined(CONFIG_NO_HZ_FULL) 1218 if (tick_nohz_full_running && !cpumask_empty(tick_nohz_full_mask)) 1219 cpumask = tick_nohz_full_mask; 1220 #endif 1221 1222 if (cpumask) { 1223 if (!cpumask_available(rcu_nocb_mask)) { 1224 if (!zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL)) { 1225 pr_info("rcu_nocb_mask allocation failed, callback offloading disabled.\n"); 1226 return; 1227 } 1228 } 1229 1230 cpumask_or(rcu_nocb_mask, rcu_nocb_mask, cpumask); 1231 } 1232 1233 if (!cpumask_available(rcu_nocb_mask)) 1234 return; 1235 1236 if (!cpumask_subset(rcu_nocb_mask, cpu_possible_mask)) { 1237 pr_info("\tNote: kernel parameter 'rcu_nocbs=', 'nohz_full', or 'isolcpus=' contains nonexistent CPUs.\n"); 1238 cpumask_and(rcu_nocb_mask, cpu_possible_mask, 1239 rcu_nocb_mask); 1240 } 1241 if (cpumask_empty(rcu_nocb_mask)) 1242 pr_info("\tOffload RCU callbacks from CPUs: (none).\n"); 1243 else 1244 pr_info("\tOffload RCU callbacks from CPUs: %*pbl.\n", 1245 cpumask_pr_args(rcu_nocb_mask)); 1246 if (rcu_nocb_poll) 1247 pr_info("\tPoll for callbacks from no-CBs CPUs.\n"); 1248 1249 for_each_cpu(cpu, rcu_nocb_mask) { 1250 rdp = per_cpu_ptr(&rcu_data, cpu); 1251 if (rcu_segcblist_empty(&rdp->cblist)) 1252 rcu_segcblist_init(&rdp->cblist); 1253 rcu_segcblist_offload(&rdp->cblist, true); 1254 rcu_segcblist_set_flags(&rdp->cblist, SEGCBLIST_KTHREAD_CB | SEGCBLIST_KTHREAD_GP); 1255 rcu_segcblist_clear_flags(&rdp->cblist, SEGCBLIST_RCU_CORE); 1256 } 1257 rcu_organize_nocb_kthreads(); 1258 } 1259 -- 0-DAY CI Kernel Test Service https://01.org/lkp
