diff options
Diffstat (limited to 'kernel/rcu/tree.h')
| -rw-r--r-- | kernel/rcu/tree.h | 77 |
1 files changed, 61 insertions, 16 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 0f69a79c5b7d..8e7b1843896e 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -139,7 +139,7 @@ struct rcu_node { unsigned long expmask; /* Groups that have ->blkd_tasks */ /* elements that need to drain to allow the */ /* current expedited grace period to */ - /* complete (only for TREE_PREEMPT_RCU). */ + /* complete (only for PREEMPT_RCU). */ unsigned long qsmaskinit; /* Per-GP initial value for qsmask & expmask. */ unsigned long grpmask; /* Mask to apply to parent qsmask. */ @@ -172,6 +172,14 @@ struct rcu_node { /* queued on this rcu_node structure that */ /* are blocking the current grace period, */ /* there can be no such task. */ + struct completion boost_completion; + /* Used to ensure that the rt_mutex used */ + /* to carry out the boosting is fully */ + /* released with no future boostee accesses */ + /* before that rt_mutex is re-initialized. */ + struct rt_mutex boost_mtx; + /* Used only for the priority-boosting */ + /* side effect, not as a lock. */ unsigned long boost_time; /* When to start boosting (jiffies). */ struct task_struct *boost_kthread_task; @@ -334,11 +342,29 @@ struct rcu_data { struct rcu_head **nocb_tail; atomic_long_t nocb_q_count; /* # CBs waiting for kthread */ atomic_long_t nocb_q_count_lazy; /* (approximate). */ + struct rcu_head *nocb_follower_head; /* CBs ready to invoke. */ + struct rcu_head **nocb_follower_tail; + atomic_long_t nocb_follower_count; /* # CBs ready to invoke. */ + atomic_long_t nocb_follower_count_lazy; /* (approximate). */ int nocb_p_count; /* # CBs being invoked by kthread */ int nocb_p_count_lazy; /* (approximate). */ wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */ struct task_struct *nocb_kthread; - bool nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ + int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ + + /* 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; + long nocb_gp_count; + long nocb_gp_count_lazy; + 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. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ /* 8) RCU CPU stall data. */ @@ -357,6 +383,11 @@ struct rcu_data { #define RCU_FORCE_QS 3 /* Need to force quiescent state. */ #define RCU_SIGNAL_INIT RCU_SAVE_DYNTICK +/* Values for nocb_defer_wakeup field in struct rcu_data. */ +#define RCU_NOGP_WAKE_NOT 0 +#define RCU_NOGP_WAKE 1 +#define RCU_NOGP_WAKE_FORCE 2 + #define RCU_JIFFIES_TILL_FORCE_QS (1 + (HZ > 250) + (HZ > 500)) /* For jiffies_till_first_fqs and */ /* and jiffies_till_next_fqs. */ @@ -499,10 +530,10 @@ DECLARE_PER_CPU(struct rcu_data, rcu_sched_data); extern struct rcu_state rcu_bh_state; DECLARE_PER_CPU(struct rcu_data, rcu_bh_data); -#ifdef CONFIG_TREE_PREEMPT_RCU +#ifdef CONFIG_PREEMPT_RCU extern struct rcu_state rcu_preempt_state; DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data); -#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ +#endif /* #ifdef CONFIG_PREEMPT_RCU */ #ifdef CONFIG_RCU_BOOST DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status); @@ -516,7 +547,7 @@ DECLARE_PER_CPU(char, rcu_cpu_has_work); /* Forward declarations for rcutree_plugin.h */ static void rcu_bootup_announce(void); long rcu_batches_completed(void); -static void rcu_preempt_note_context_switch(int cpu); +static void rcu_preempt_note_context_switch(void); static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp); #ifdef CONFIG_HOTPLUG_CPU static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, @@ -530,12 +561,12 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_data *rdp); #endif /* #ifdef CONFIG_HOTPLUG_CPU */ -static void rcu_preempt_check_callbacks(int cpu); +static void rcu_preempt_check_callbacks(void); void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); -#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU) +#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PREEMPT_RCU) static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, bool wake); -#endif /* #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_TREE_PREEMPT_RCU) */ +#endif /* #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PREEMPT_RCU) */ static void __init __rcu_init_preempt(void); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); @@ -546,15 +577,17 @@ static void rcu_preempt_do_callbacks(void); static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp); #endif /* #ifdef CONFIG_RCU_BOOST */ +static void __init rcu_spawn_boost_kthreads(void); static void rcu_prepare_kthreads(int cpu); -static void rcu_cleanup_after_idle(int cpu); -static void rcu_prepare_for_idle(int cpu); +static void rcu_cleanup_after_idle(void); +static void rcu_prepare_for_idle(void); static void rcu_idle_count_callbacks_posted(void); static void print_cpu_stall_info_begin(void); static void print_cpu_stall_info(struct rcu_state *rsp, int cpu); static void print_cpu_stall_info_end(void); static void zero_cpu_stall_ticks(struct rcu_data *rdp); static void increment_cpu_stall_ticks(void); +static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu); static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq); static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp); static void rcu_init_one_nocb(struct rcu_node *rnp); @@ -563,14 +596,18 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, static bool rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, struct rcu_data *rdp, unsigned long flags); -static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp); +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_nocb_kthreads(struct rcu_state *rsp); +static void rcu_spawn_all_nocb_kthreads(int cpu); +static void __init rcu_spawn_nocb_kthreads(void); +#ifdef CONFIG_RCU_NOCB_CPU +static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp); +#endif /* #ifdef CONFIG_RCU_NOCB_CPU */ static void __maybe_unused rcu_kick_nohz_cpu(int cpu); static bool init_nocb_callback_list(struct rcu_data *rdp); -static void rcu_sysidle_enter(struct rcu_dynticks *rdtp, int irq); -static void rcu_sysidle_exit(struct rcu_dynticks *rdtp, int irq); +static void rcu_sysidle_enter(int irq); +static void rcu_sysidle_exit(int irq); static void rcu_sysidle_check_cpu(struct rcu_data *rdp, bool *isidle, unsigned long *maxj); static bool is_sysidle_rcu_state(struct rcu_state *rsp); @@ -579,6 +616,8 @@ static void rcu_sysidle_report_gp(struct rcu_state *rsp, int isidle, static void rcu_bind_gp_kthread(void); static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp); static bool rcu_nohz_full_cpu(struct rcu_state *rsp); +static void rcu_dynticks_task_enter(void); +static void rcu_dynticks_task_exit(void); #endif /* #ifndef RCU_TREE_NONCORE */ @@ -587,8 +626,14 @@ static bool rcu_nohz_full_cpu(struct rcu_state *rsp); /* Sum up queue lengths for tracing. */ static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll) { - *ql = atomic_long_read(&rdp->nocb_q_count) + rdp->nocb_p_count; - *qll = atomic_long_read(&rdp->nocb_q_count_lazy) + rdp->nocb_p_count_lazy; + *ql = atomic_long_read(&rdp->nocb_q_count) + + rdp->nocb_p_count + + atomic_long_read(&rdp->nocb_follower_count) + + rdp->nocb_p_count + rdp->nocb_gp_count; + *qll = atomic_long_read(&rdp->nocb_q_count_lazy) + + rdp->nocb_p_count_lazy + + atomic_long_read(&rdp->nocb_follower_count_lazy) + + rdp->nocb_p_count_lazy + rdp->nocb_gp_count_lazy; } #else /* #ifdef CONFIG_RCU_NOCB_CPU */ static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll) |