diff options
author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2011-06-16 00:47:09 +0200 |
---|---|---|
committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2011-06-16 08:07:21 +0200 |
commit | a46e0899eec7a3069bcadd45dfba7bf67c6ed016 (patch) | |
tree | 78158b4056fe1365d5086f66769abdc3ef2643c3 /kernel/rcutree.h | |
parent | rcu: Use softirq to address performance regression (diff) | |
download | linux-a46e0899eec7a3069bcadd45dfba7bf67c6ed016.tar.xz linux-a46e0899eec7a3069bcadd45dfba7bf67c6ed016.zip |
rcu: use softirq instead of kthreads except when RCU_BOOST=y
This patch #ifdefs RCU kthreads out of the kernel unless RCU_BOOST=y,
thus eliminating context-switch overhead if RCU priority boosting has
not been configured.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcutree.h')
-rw-r--r-- | kernel/rcutree.h | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 0fed6b934d2a..434288c7ad88 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -369,6 +369,7 @@ struct rcu_state { /* period because */ /* force_quiescent_state() */ /* was running. */ + u8 boost; /* Subject to priority boost. */ unsigned long gpnum; /* Current gp number. */ unsigned long completed; /* # of last completed gp. */ @@ -439,7 +440,6 @@ static void rcu_preempt_offline_cpu(int cpu); #endif /* #ifdef CONFIG_HOTPLUG_CPU */ static void rcu_preempt_check_callbacks(int cpu); static void rcu_preempt_process_callbacks(void); -static void rcu_preempt_do_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) static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp); @@ -451,11 +451,15 @@ 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 rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); +static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); +static void invoke_rcu_callbacks_kthread(void); +#ifdef CONFIG_RCU_BOOST +static void rcu_preempt_do_callbacks(void); static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, cpumask_var_t cm); -static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp, int rnp_index); +#endif /* #ifdef CONFIG_RCU_BOOST */ #endif /* #ifndef RCU_TREE_NONCORE */ |