[kbuild-all] Re: kernel/sched/psi.c:1193:6: warning: no previous prototype for 'psi_trigger_destroy'

On Mon, Jan 24, 2022 at 4:27 PM kernel test robot <lkp(a)intel.com&gt; wrote: https://lore.kernel.org/all/YemFa5ouZXEnR%2FD+@cmpxchg.org fixes these warnings. > > vim +/psi_trigger_destroy +1193 kernel/sched/psi.c > > 1192 > > 1193 void psi_trigger_destroy(struct psi_trigger *t) > 1194 { > 1195 struct psi_group *group; > 1196 struct task_struct *task_to_destroy = NULL; > 1197 > 1198 /* > 1199 * We do not check psi_disabled since it might have been disabled after > 1200 * the trigger got created. > 1201 */ > 1202 if (!t) > 1203 return; > 1204 > 1205 group = t->group; > 1206 /* > 1207 * Wakeup waiters to stop polling. Can happen if cgroup is deleted > 1208 * from under a polling process. > 1209 */ > 1210 wake_up_interruptible(&t->event_wait); > 1211 > 1212 mutex_lock(&group->trigger_lock); > 1213 > 1214 if (!list_empty(&t->node)) { > 1215 struct psi_trigger *tmp; > 1216 u64 period = ULLONG_MAX; > 1217 > 1218 list_del(&t->node); > 1219 group->nr_triggers[t->state]--; > 1220 if (!group->nr_triggers[t->state]) > 1221 group->poll_states &= ~(1 << t->state); > 1222 /* reset min update period for the remaining triggers */ > 1223 list_for_each_entry(tmp, &group->triggers, node) > 1224 period = min(period, div_u64(tmp->win.size, > 1225 UPDATES_PER_WINDOW)); > 1226 group->poll_min_period = period; > 1227 /* Destroy poll_task when the last trigger is destroyed */ > 1228 if (group->poll_states == 0) { > 1229 group->polling_until = 0; > 1230 task_to_destroy = rcu_dereference_protected( > 1231 group->poll_task, > 1232 lockdep_is_held(&group->trigger_lock)); > 1233 rcu_assign_pointer(group->poll_task, NULL); > 1234 del_timer(&group->poll_timer); > 1235 } > 1236 } > 1237 > 1238 mutex_unlock(&group->trigger_lock); > 1239 > 1240 /* > 1241 * Wait for psi_schedule_poll_work RCU to complete its read-side > 1242 * critical section before destroying the trigger and optionally the > 1243 * poll_task. > 1244 */ > 1245 synchronize_rcu(); > 1246 /* > 1247 * Stop kthread 'psimon' after releasing trigger_lock to prevent a > 1248 * deadlock while waiting for psi_poll_work to acquire trigger_lock > 1249 */ > 1250 if (task_to_destroy) { > 1251 /* > 1252 * After the RCU grace period has expired, the worker > 1253 * can no longer be found through group->poll_task. > 1254 */ > 1255 kthread_stop(task_to_destroy); > 1256 } > 1257 kfree(t); > 1258 } > 1259 > > --- > 0-DAY CI Kernel Test Service, Intel Corporation > https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org