Hi lijianzhong, FYI, the error/warning still remains. tree: https://android.googlesource.com/kernel/common android12-5.10 head: 129e04dc199ef790bd0c2bd31e8d9ae909e44b57 commit: 54f66141a8834e27601fe594d68a97db01bb86b6 [8046/13750] ANDROID: sched: Add vendor hooks for sched. config: arm-randconfig-r026-20211014 (attached as .config) compiler: arm-linux-gnueabi-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 git remote add android-common https://android.googlesource.com/kernel/common git fetch --no-tags android-common android12-5.10 git checkout 54f66141a8834e27601fe594d68a97db01bb86b6 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): 4424 | void set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) | ^~~~~~~~~~~~~~~ kernel/sched/fair.c:5408:6: warning: no previous prototype for 'init_cfs_bandwidth' [-Wmissing-prototypes] 5408 | void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {} | ^~~~~~~~~~~~~~~~~~ kernel/sched/fair.c:11341:6: warning: no previous prototype for 'free_fair_sched_group' [-Wmissing-prototypes] 11341 | void free_fair_sched_group(struct task_group *tg) { } | ^~~~~~~~~~~~~~~~~~~~~ kernel/sched/fair.c:11343:5: warning: no previous prototype for 'alloc_fair_sched_group' [-Wmissing-prototypes] 11343 | int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) | ^~~~~~~~~~~~~~~~~~~~~~ kernel/sched/fair.c:11348:6: warning: no previous prototype for 'online_fair_sched_group' [-Wmissing-prototypes] 11348 | void online_fair_sched_group(struct task_group *tg) { } | ^~~~~~~~~~~~~~~~~~~~~~~ kernel/sched/fair.c:11350:6: warning: no previous prototype for 'unregister_fair_sched_group' [-Wmissing-prototypes] 11350 | void unregister_fair_sched_group(struct task_group *tg) { } | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/set_next_entity +4424 kernel/sched/fair.c 4423 4425 { 4426 /* 'current' is not kept within the tree. */ 4427 if (se->on_rq) { 4428 /* 4429 * Any task has to be enqueued before it get to execute on 4430 * a CPU. So account for the time it spent waiting on the 4431 * runqueue. 4432 */ 4433 update_stats_wait_end(cfs_rq, se); 4434 __dequeue_entity(cfs_rq, se); 4435 update_load_avg(cfs_rq, se, UPDATE_TG); 4436 } 4437 4438 update_stats_curr_start(cfs_rq, se); 4439 cfs_rq->curr = se; 4440 4441 /* 4442 * Track our maximum slice length, if the CPU's load is at 4443 * least twice that of our own weight (i.e. dont track it 4444 * when there are only lesser-weight tasks around): 4445 */ 4446 if (schedstat_enabled() && 4447 rq_of(cfs_rq)->cfs.load.weight >= 2*se->load.weight) { 4448 schedstat_set(se->statistics.slice_max, 4449 max((u64)schedstat_val(se->statistics.slice_max), 4450 se->sum_exec_runtime - se->prev_sum_exec_runtime)); 4451 } 4452 4453 se->prev_sum_exec_runtime = se->sum_exec_runtime; 4454 } 4455 EXPORT_SYMBOL_GPL(set_next_entity); 4456 4457 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org