tree: https://chromium.googlesource.com/chromiumos/third_party/kernel chromeos-4.19 head: d2eeef58809494b0ea811ce578163de7a2478a22 commit: 231822f7cf3229131789ef0315fe70050be7bb6c [61/62] FIXUP: FROMLIST: sched/fair: core wide vruntime comparison config: x86_64-randconfig-a001-20200617 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 487ca07fcc75d52755c9fe2ee05bcb3b6eeeec44) 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 # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu git checkout 231822f7cf3229131789ef0315fe70050be7bb6c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>, old ones prefixed by <<): kernel/sched/core.c:1980:6: warning: no previous prototype for function 'sched_set_stop_task' [-Wmissing-prototypes] void sched_set_stop_task(int cpu, struct task_struct *stop) ^ kernel/sched/core.c:1980:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void sched_set_stop_task(int cpu, struct task_struct *stop) ^ static kernel/sched/core.c:4613:35: warning: no previous prototype for function 'schedule_user' [-Wmissing-prototypes] asmlinkage __visible void __sched schedule_user(void) ^ kernel/sched/core.c:4613:22: note: declare 'static' if the function is not intended to be used outside of this translation unit asmlinkage __visible void __sched schedule_user(void) ^ static kernel/sched/core.c:4752:35: warning: no previous prototype for function 'preempt_schedule_irq' [-Wmissing-prototypes] asmlinkage __visible void __sched preempt_schedule_irq(void) ^ kernel/sched/core.c:4752:22: note: declare 'static' if the function is not intended to be used outside of this translation unit asmlinkage __visible void __sched preempt_schedule_irq(void) ^ static core_sched_cpu_update(cpu, CPU_ACTIVATE); ^~~~~~~~~~~~ PGACTIVATE include/linux/vm_event_item.h:29:11: note: 'PGACTIVATE' declared here PGFREE, PGACTIVATE, PGDEACTIVATE, PGLAZYFREE, ^ core_sched_cpu_update(cpu, CPU_DEACTIVATE); ^~~~~~~~~~~~~~ PGDEACTIVATE include/linux/vm_event_item.h:29:23: note: 'PGDEACTIVATE' declared here PGFREE, PGACTIVATE, PGDEACTIVATE, PGLAZYFREE, ^ 3 warnings and 2 errors generated. vim +6813 kernel/sched/core.c e761b772523427 kernel/sched.c Max Krasnyansky 2008-07-15 6800 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6801 int sched_cpu_activate(unsigned int cpu) 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6802 { 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6803 struct rq *rq = cpu_rq(cpu); 8a8c69c3277886 kernel/sched/core.c Peter Zijlstra 2016-10-04 6804 struct rq_flags rf; 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6805 ba2591a5993eab kernel/sched/core.c Peter Zijlstra 2018-05-29 6806 #ifdef CONFIG_SCHED_SMT ba2591a5993eab kernel/sched/core.c Peter Zijlstra 2018-05-29 6807 /* a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6808) * When going up, increment the number of cores with SMT present. ba2591a5993eab kernel/sched/core.c Peter Zijlstra 2018-05-29 6809 */ 56b6a5dcf7349d kernel/sched/core.c Peter Zijlstra 2019-02-18 6810 if (cpumask_weight(cpu_smt_mask(cpu)) == 2) { a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6811) static_branch_inc_cpuslocked(&sched_smt_present); 56b6a5dcf7349d kernel/sched/core.c Peter Zijlstra 2019-02-18 6812 } cfff5c5f9c0a9b kernel/sched/core.c Tim Chen 2020-01-07 @6813 core_sched_cpu_update(cpu, CPU_ACTIVATE); ba2591a5993eab kernel/sched/core.c Peter Zijlstra 2018-05-29 6814 #endif 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6815 set_cpu_active(cpu, true); 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6816 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6817 if (sched_smp_initialized) { 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6818 sched_domains_numa_masks_set(cpu); 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6819 cpuset_cpu_active(); e761b772523427 kernel/sched.c Max Krasnyansky 2008-07-15 6820 } 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6821 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6822 /* 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6823 * Put the rq online, if not already. This happens: 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6824 * 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6825 * 1) In the early boot process, because we build the real domains d1ccc66df8bfe3 kernel/sched/core.c Ingo Molnar 2017-02-01 6826 * after all CPUs have been brought up. 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6827 * 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6828 * 2) At runtime, if cpuset_cpu_active() fails to rebuild the 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6829 * domains. 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6830 */ 8a8c69c3277886 kernel/sched/core.c Peter Zijlstra 2016-10-04 6831 rq_lock_irqsave(rq, &rf); 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6832 if (rq->rd) { 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6833 BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6834 set_rq_online(rq); 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6835 } 8a8c69c3277886 kernel/sched/core.c Peter Zijlstra 2016-10-04 6836 rq_unlock_irqrestore(rq, &rf); 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6837 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6838 update_max_interval(); 7d97669933eb94 kernel/sched/core.c Thomas Gleixner 2016-03-10 6839 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6840 return 0; 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6841 } 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6842 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6843 int sched_cpu_deactivate(unsigned int cpu) 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6844 { 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6845 int ret; 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6846 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6847 set_cpu_active(cpu, false); b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6848 /* b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6849 * We've cleared cpu_active_mask, wait for all preempt-disabled and RCU b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6850 * users of this state to go away such that all new such users will b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6851 * observe it. b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6852 * b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6853 * Do sync before park smpboot threads to take care the rcu boost case. b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6854 */ b2454caa8977ad kernel/sched/core.c Peter Zijlstra 2016-03-10 6855 synchronize_rcu_mult(call_rcu, call_rcu_sched); 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6856 a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6857) #ifdef CONFIG_SCHED_SMT a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6858) /* a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6859) * When going down, decrement the number of cores with SMT present. a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6860) */ 56b6a5dcf7349d kernel/sched/core.c Peter Zijlstra 2019-02-18 6861 if (cpumask_weight(cpu_smt_mask(cpu)) == 2) { a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6862) static_branch_dec_cpuslocked(&sched_smt_present); 56b6a5dcf7349d kernel/sched/core.c Peter Zijlstra 2019-02-18 6863 56b6a5dcf7349d kernel/sched/core.c Peter Zijlstra 2019-02-18 6864 } cfff5c5f9c0a9b kernel/sched/core.c Tim Chen 2020-01-07 @6865 core_sched_cpu_update(cpu, CPU_DEACTIVATE); a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6866) #endif a2c094816f894b kernel/sched/core.c Peter Zijlstra (Intel 2018-11-25 6867) 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6868 if (!sched_smp_initialized) 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6869 return 0; 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6870 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6871 ret = cpuset_cpu_inactive(cpu); 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6872 if (ret) { 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6873 set_cpu_active(cpu, true); 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6874 return ret; 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6875 } 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6876 sched_domains_numa_masks_clear(cpu); 40190a78f85fec kernel/sched/core.c Thomas Gleixner 2016-03-10 6877 return 0; 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6878 } 135fb3e19773e6 kernel/sched/core.c Thomas Gleixner 2016-03-10 6879 :::::: The code at line 6813 was first introduced by commit :::::: cfff5c5f9c0a9b899e38ed65fb7d925d6b5a5bfa FROMLIST: sched/core: Update core scheduler queue when taking cpu online/offline :::::: TO: Tim Chen <tim.c.chen(a)linux.intel.com&gt; :::::: CC: Commit Bot <commit-bot(a)chromium.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org