diff options
Diffstat (limited to 'kernel/rcu/tree.h')
-rw-r--r-- | kernel/rcu/tree.h | 81 |
1 files changed, 52 insertions, 29 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 7acaf3a62d39..c612f306fe89 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -194,29 +194,38 @@ struct rcu_data { /* 5) Callback offloading. */ #ifdef CONFIG_RCU_NOCB_CPU - struct rcu_head *nocb_head; /* CBs waiting for kthread. */ - struct rcu_head **nocb_tail; - atomic_long_t nocb_q_count; /* # CBs waiting for nocb */ - atomic_long_t nocb_q_count_lazy; /* invocation (all stages). */ - struct rcu_head *nocb_follower_head; /* CBs ready to invoke. */ - struct rcu_head **nocb_follower_tail; - struct swait_queue_head nocb_wq; /* For nocb kthreads to sleep on. */ - struct task_struct *nocb_kthread; + struct swait_queue_head nocb_cb_wq; /* For nocb kthreads to sleep on. */ + struct task_struct *nocb_gp_kthread; raw_spinlock_t nocb_lock; /* Guard following pair of fields. */ + atomic_t nocb_lock_contended; /* Contention experienced. */ int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ struct timer_list nocb_timer; /* Enforce finite deferral. */ - - /* The following fields are used by the leader, hence own cacheline. */ - struct rcu_head *nocb_gp_head ____cacheline_internodealigned_in_smp; - /* CBs waiting for GP. */ - struct rcu_head **nocb_gp_tail; - bool nocb_leader_sleep; /* Is the nocb leader thread asleep? */ - struct rcu_data *nocb_next_follower; - /* Next follower in wakeup chain. */ - - /* The following fields are used by the follower, hence new cachline. */ - struct rcu_data *nocb_leader ____cacheline_internodealigned_in_smp; - /* Leader CPU takes GP-end wakeups. */ + unsigned long nocb_gp_adv_time; /* Last call_rcu() CB adv (jiffies). */ + + /* The following fields are used by call_rcu, hence own cacheline. */ + raw_spinlock_t nocb_bypass_lock ____cacheline_internodealigned_in_smp; + struct rcu_cblist nocb_bypass; /* Lock-contention-bypass CB list. */ + unsigned long nocb_bypass_first; /* Time (jiffies) of first enqueue. */ + unsigned long nocb_nobypass_last; /* Last ->cblist enqueue (jiffies). */ + int nocb_nobypass_count; /* # ->cblist enqueues at ^^^ time. */ + + /* The following fields are used by GP kthread, hence own cacheline. */ + raw_spinlock_t nocb_gp_lock ____cacheline_internodealigned_in_smp; + struct timer_list nocb_bypass_timer; /* Force nocb_bypass flush. */ + u8 nocb_gp_sleep; /* Is the nocb GP thread asleep? */ + u8 nocb_gp_bypass; /* Found a bypass on last scan? */ + u8 nocb_gp_gp; /* GP to wait for on last scan? */ + unsigned long nocb_gp_seq; /* If so, ->gp_seq to wait for. */ + unsigned long nocb_gp_loops; /* # passes through wait code. */ + struct swait_queue_head nocb_gp_wq; /* For nocb kthreads to sleep on. */ + bool nocb_cb_sleep; /* Is the nocb CB thread asleep? */ + struct task_struct *nocb_cb_kthread; + struct rcu_data *nocb_next_cb_rdp; + /* Next rcu_data in wakeup chain. */ + + /* The following fields are used by CB kthread, hence new cacheline. */ + struct rcu_data *nocb_gp_rdp ____cacheline_internodealigned_in_smp; + /* GP rdp takes GP-end wakeups. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ /* 6) RCU priority boosting. */ @@ -419,25 +428,39 @@ static bool rcu_preempt_has_tasks(struct rcu_node *rnp); static bool rcu_preempt_need_deferred_qs(struct task_struct *t); static void rcu_preempt_deferred_qs(struct task_struct *t); static void zero_cpu_stall_ticks(struct rcu_data *rdp); -static bool rcu_nocb_cpu_needs_barrier(int cpu); static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp); static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq); static void rcu_init_one_nocb(struct rcu_node *rnp); -static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, - bool lazy, unsigned long flags); -static bool rcu_nocb_adopt_orphan_cbs(struct rcu_data *my_rdp, - struct rcu_data *rdp, - unsigned long flags); +static bool rcu_nocb_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp, + unsigned long j); +static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp, + bool *was_alldone, unsigned long flags); +static void __call_rcu_nocb_wake(struct rcu_data *rdp, bool was_empty, + unsigned long flags); static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp); static void do_nocb_deferred_wakeup(struct rcu_data *rdp); static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp); static void rcu_spawn_cpu_nocb_kthread(int cpu); static void __init rcu_spawn_nocb_kthreads(void); +static void show_rcu_nocb_state(struct rcu_data *rdp); +static void rcu_nocb_lock(struct rcu_data *rdp); +static void rcu_nocb_unlock(struct rcu_data *rdp); +static void rcu_nocb_unlock_irqrestore(struct rcu_data *rdp, + unsigned long flags); +static void rcu_lockdep_assert_cblist_protected(struct rcu_data *rdp); #ifdef CONFIG_RCU_NOCB_CPU static void __init rcu_organize_nocb_kthreads(void); -#endif /* #ifdef CONFIG_RCU_NOCB_CPU */ -static bool init_nocb_callback_list(struct rcu_data *rdp); -static unsigned long rcu_get_n_cbs_nocb_cpu(struct rcu_data *rdp); +#define rcu_nocb_lock_irqsave(rdp, flags) \ +do { \ + if (!rcu_segcblist_is_offloaded(&(rdp)->cblist)) \ + local_irq_save(flags); \ + else \ + raw_spin_lock_irqsave(&(rdp)->nocb_lock, (flags)); \ +} while (0) +#else /* #ifdef CONFIG_RCU_NOCB_CPU */ +#define rcu_nocb_lock_irqsave(rdp, flags) local_irq_save(flags) +#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */ + static void rcu_bind_gp_kthread(void); static bool rcu_nohz_full_cpu(void); static void rcu_dynticks_task_enter(void); |