From 2927a689e8ad5c12d6300b41e873d2b7957bc0e1 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 4 Mar 2015 07:53:04 -0800 Subject: [PATCH] rcu: Create an immutable rcu_data_p pointer to default rcu_data structure This commit creates an immutable rcu_data_p pointer that references rcu_preempt_data for TREE_PREEMPT_RCU builds and that references rcu_sched_data for TREE_RCU builds. This rcu_data_p pointer will enable more code to move from #ifdef to IS_ENABLED(). Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 1 + kernel/rcu/tree_plugin.h | 16 +++++++++------- 2 files changed, 10 insertions(+), 7 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f031700514dd..213f644d6fb1 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -111,6 +111,7 @@ RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched); RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh); static struct rcu_state *const rcu_state_p; +static struct rcu_data __percpu *const rcu_data_p; LIST_HEAD(rcu_struct_flavors); /* Increase (but not decrease) the CONFIG_RCU_FANOUT_LEAF at boot time. */ diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 18b057adc21a..5c0122f09ed0 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -101,6 +101,7 @@ static void __init rcu_bootup_announce_oddness(void) RCU_STATE_INITIALIZER(rcu_preempt, 'p', call_rcu); static struct rcu_state *const rcu_state_p = &rcu_preempt_state; +static struct rcu_data __percpu *const rcu_data_p = &rcu_preempt_data; static int rcu_preempted_readers_exp(struct rcu_node *rnp); static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, @@ -126,11 +127,11 @@ static void __init rcu_bootup_announce(void) */ static void rcu_preempt_qs(void) { - if (!__this_cpu_read(rcu_preempt_data.passed_quiesce)) { + if (!__this_cpu_read(rcu_data_p->passed_quiesce)) { trace_rcu_grace_period(TPS("rcu_preempt"), - __this_cpu_read(rcu_preempt_data.gpnum), + __this_cpu_read(rcu_data_p->gpnum), TPS("cpuqs")); - __this_cpu_write(rcu_preempt_data.passed_quiesce, 1); + __this_cpu_write(rcu_data_p->passed_quiesce, 1); barrier(); /* Coordinate with rcu_preempt_check_callbacks(). */ current->rcu_read_unlock_special.b.need_qs = false; } @@ -495,8 +496,8 @@ static void rcu_preempt_check_callbacks(void) return; } if (t->rcu_read_lock_nesting > 0 && - __this_cpu_read(rcu_preempt_data.qs_pending) && - !__this_cpu_read(rcu_preempt_data.passed_quiesce)) + __this_cpu_read(rcu_data_p->qs_pending) && + !__this_cpu_read(rcu_data_p->passed_quiesce)) t->rcu_read_unlock_special.b.need_qs = true; } @@ -504,7 +505,7 @@ static void rcu_preempt_check_callbacks(void) static void rcu_preempt_do_callbacks(void) { - rcu_do_batch(rcu_state_p, this_cpu_ptr(&rcu_preempt_data)); + rcu_do_batch(rcu_state_p, this_cpu_ptr(rcu_data_p)); } #endif /* #ifdef CONFIG_RCU_BOOST */ @@ -811,7 +812,7 @@ EXPORT_SYMBOL_GPL(rcu_barrier); */ static void __init __rcu_init_preempt(void) { - rcu_init_one(rcu_state_p, &rcu_preempt_data); + rcu_init_one(rcu_state_p, rcu_data_p); } /* @@ -835,6 +836,7 @@ void exit_rcu(void) #else /* #ifdef CONFIG_PREEMPT_RCU */ static struct rcu_state *const rcu_state_p = &rcu_sched_state; +static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data; /* * Tell them what RCU they are running. -- 2.39.5