diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 5d96d68d20f8..05e254e930e3 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -95,7 +95,6 @@ static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task); DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status); DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu); DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); -static DEFINE_PER_CPU(wait_queue_head_t, rcu_cpu_wq); DEFINE_PER_CPU(char, rcu_cpu_has_work); static char rcu_kthreads_spawnable; @@ -1476,7 +1475,7 @@ static void invoke_rcu_cpu_kthread(void) local_irq_restore(flags); return; } - wake_up(&__get_cpu_var(rcu_cpu_wq)); + wake_up_process(__this_cpu_read(rcu_cpu_kthread_task)); local_irq_restore(flags); } @@ -1596,14 +1595,12 @@ static int rcu_cpu_kthread(void *arg) unsigned long flags; int spincnt = 0; unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu); - wait_queue_head_t *wqp = &per_cpu(rcu_cpu_wq, cpu); char work; char *workp = &per_cpu(rcu_cpu_has_work, cpu); for (;;) { *statusp = RCU_KTHREAD_WAITING; - wait_event_interruptible(*wqp, - *workp != 0 || kthread_should_stop()); + rcu_wait(*workp != 0 || kthread_should_stop()); local_bh_disable(); if (rcu_cpu_kthread_should_stop(cpu)) { local_bh_enable(); @@ -1654,7 +1651,6 @@ static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu) per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu; WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL); per_cpu(rcu_cpu_kthread_task, cpu) = t; - wake_up_process(t); sp.sched_priority = RCU_KTHREAD_PRIO; sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); return 0; @@ -1677,8 +1673,7 @@ static int rcu_node_kthread(void *arg) for (;;) { rnp->node_kthread_status = RCU_KTHREAD_WAITING; - wait_event_interruptible(rnp->node_wq, - atomic_read(&rnp->wakemask) != 0); + rcu_wait(atomic_read(&rnp->wakemask) != 0); rnp->node_kthread_status = RCU_KTHREAD_RUNNING; raw_spin_lock_irqsave(&rnp->lock, flags); mask = atomic_xchg(&rnp->wakemask, 0); @@ -1762,7 +1757,6 @@ static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp, raw_spin_lock_irqsave(&rnp->lock, flags); rnp->node_kthread_task = t; raw_spin_unlock_irqrestore(&rnp->lock, flags); - wake_up_process(t); sp.sched_priority = 99; sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); } @@ -1779,21 +1773,16 @@ static int __init rcu_spawn_kthreads(void) rcu_kthreads_spawnable = 1; for_each_possible_cpu(cpu) { - init_waitqueue_head(&per_cpu(rcu_cpu_wq, cpu)); per_cpu(rcu_cpu_has_work, cpu) = 0; if (cpu_online(cpu)) (void)rcu_spawn_one_cpu_kthread(cpu); } rnp = rcu_get_root(rcu_state); - init_waitqueue_head(&rnp->node_wq); - rcu_init_boost_waitqueue(rnp); (void)rcu_spawn_one_node_kthread(rcu_state, rnp); - if (NUM_RCU_NODES > 1) - rcu_for_each_leaf_node(rcu_state, rnp) { - init_waitqueue_head(&rnp->node_wq); - rcu_init_boost_waitqueue(rnp); + if (NUM_RCU_NODES > 1) { + rcu_for_each_leaf_node(rcu_state, rnp) (void)rcu_spawn_one_node_kthread(rcu_state, rnp); - } + } return 0; } early_initcall(rcu_spawn_kthreads); diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 561dcb9a8d2c..7b9a08b4aaea 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -159,9 +159,6 @@ struct rcu_node { struct task_struct *boost_kthread_task; /* kthread that takes care of priority */ /* boosting for this rcu_node structure. */ - wait_queue_head_t boost_wq; - /* Wait queue on which to park the boost */ - /* kthread. */ unsigned int boost_kthread_status; /* State of boost_kthread_task for tracing. */ unsigned long n_tasks_boosted; @@ -188,9 +185,6 @@ struct rcu_node { /* kthread that takes care of this rcu_node */ /* structure, for example, awakening the */ /* per-CPU kthreads as needed. */ - wait_queue_head_t node_wq; - /* Wait queue on which to park the per-node */ - /* kthread. */ unsigned int node_kthread_status; /* State of node_kthread_task for tracing. */ } ____cacheline_internodealigned_in_smp; @@ -336,6 +330,16 @@ struct rcu_data { /* scheduling clock irq */ /* before ratting on them. */ +#define rcu_wait(cond) \ +do { \ + for (;;) { \ + set_current_state(TASK_INTERRUPTIBLE); \ + if (cond) \ + break; \ + schedule(); \ + } \ + __set_current_state(TASK_RUNNING); \ +} while (0) /* * RCU global state, including node hierarchy. This hierarchy is @@ -445,7 +449,6 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu); static void rcu_preempt_send_cbs_to_online(void); static void __init __rcu_init_preempt(void); static void rcu_needs_cpu_flush(void); -static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, cpumask_var_t cm); diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index ed339702481d..049f2787a984 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -1196,8 +1196,7 @@ static int rcu_boost_kthread(void *arg) for (;;) { rnp->boost_kthread_status = RCU_KTHREAD_WAITING; - wait_event_interruptible(rnp->boost_wq, rnp->boost_tasks || - rnp->exp_tasks); + rcu_wait(rnp->boost_tasks || rnp->exp_tasks); rnp->boost_kthread_status = RCU_KTHREAD_RUNNING; more2boost = rcu_boost(rnp); if (more2boost) @@ -1274,14 +1273,6 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp) rnp->boost_time = jiffies + RCU_BOOST_DELAY_JIFFIES; } -/* - * Initialize the RCU-boost waitqueue. - */ -static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp) -{ - init_waitqueue_head(&rnp->boost_wq); -} - /* * Create an RCU-boost kthread for the specified node if one does not * already exist. We only create this kthread for preemptible RCU. @@ -1306,7 +1297,6 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, raw_spin_lock_irqsave(&rnp->lock, flags); rnp->boost_kthread_task = t; raw_spin_unlock_irqrestore(&rnp->lock, flags); - wake_up_process(t); sp.sched_priority = RCU_KTHREAD_PRIO; sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); return 0; @@ -1328,10 +1318,6 @@ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp) { } -static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp) -{ -} - static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp, int rnp_index)