diff mbox

[tip/core/rcu,04/15] rcu: Place pointer to call_rcu() in rcu_data structure

Message ID 1339794370-28119-4-git-send-email-paulmck@linux.vnet.ibm.com
State Superseded
Headers show

Commit Message

Paul E. McKenney June 15, 2012, 9:05 p.m. UTC
From: "Paul E. McKenney" <paul.mckenney@linaro.org>

This is a preparatory commit for increasing rcu_barrier()'s concurrency.
It adds a pointer in the rcu_data structure to the corresponding call_rcu()
function.  This allows a pointer to the rcu_data structure to imply the
function pointer, which allows _rcu_barrier() state to be placed in the
rcu_state structure.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 kernel/rcutree.c        |   27 ++++++++++++---------------
 kernel/rcutree.h        |    2 ++
 kernel/rcutree_plugin.h |    5 +++--
 3 files changed, 17 insertions(+), 17 deletions(-)

Comments

Josh Triplett June 15, 2012, 10:08 p.m. UTC | #1
On Fri, Jun 15, 2012 at 02:05:59PM -0700, Paul E. McKenney wrote:
> From: "Paul E. McKenney" <paul.mckenney@linaro.org>
> 
> This is a preparatory commit for increasing rcu_barrier()'s concurrency.
> It adds a pointer in the rcu_data structure to the corresponding call_rcu()
> function.  This allows a pointer to the rcu_data structure to imply the
> function pointer, which allows _rcu_barrier() state to be placed in the
> rcu_state structure.
> 
> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Reviewed-by: Josh Triplett <josh@joshtriplett.org>

>  kernel/rcutree.c        |   27 ++++++++++++---------------
>  kernel/rcutree.h        |    2 ++
>  kernel/rcutree_plugin.h |    5 +++--
>  3 files changed, 17 insertions(+), 17 deletions(-)
> 
> diff --git a/kernel/rcutree.c b/kernel/rcutree.c
> index 8ce1b1d..8b3ab4e 100644
> --- a/kernel/rcutree.c
> +++ b/kernel/rcutree.c
> @@ -62,8 +62,9 @@
>  
>  static struct lock_class_key rcu_node_class[RCU_NUM_LVLS];
>  
> -#define RCU_STATE_INITIALIZER(sname) { \
> +#define RCU_STATE_INITIALIZER(sname, cr) { \
>  	.level = { &sname##_state.node[0] }, \
> +	.call = cr, \
>  	.fqs_state = RCU_GP_IDLE, \
>  	.gpnum = -300, \
>  	.completed = -300, \
> @@ -76,10 +77,11 @@ static struct lock_class_key rcu_node_class[RCU_NUM_LVLS];
>  	.name = #sname, \
>  }
>  
> -struct rcu_state rcu_sched_state = RCU_STATE_INITIALIZER(rcu_sched);
> +struct rcu_state rcu_sched_state =
> +	RCU_STATE_INITIALIZER(rcu_sched, call_rcu_sched);
>  DEFINE_PER_CPU(struct rcu_data, rcu_sched_data);
>  
> -struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh);
> +struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh, call_rcu_bh);
>  DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
>  
>  static struct rcu_state *rcu_state;
> @@ -2279,21 +2281,17 @@ static void rcu_barrier_func(void *type)
>  {
>  	int cpu = smp_processor_id();
>  	struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu);
> -	void (*call_rcu_func)(struct rcu_head *head,
> -			      void (*func)(struct rcu_head *head));
> +	struct rcu_state *rsp = type;
>  
>  	atomic_inc(&rcu_barrier_cpu_count);
> -	call_rcu_func = type;
> -	call_rcu_func(head, rcu_barrier_callback);
> +	rsp->call(head, rcu_barrier_callback);
>  }
>  
>  /*
>   * Orchestrate the specified type of RCU barrier, waiting for all
>   * RCU callbacks of the specified type to complete.
>   */
> -static void _rcu_barrier(struct rcu_state *rsp,
> -			 void (*call_rcu_func)(struct rcu_head *head,
> -					       void (*func)(struct rcu_head *head)))
> +static void _rcu_barrier(struct rcu_state *rsp)
>  {
>  	int cpu;
>  	unsigned long flags;
> @@ -2345,8 +2343,7 @@ static void _rcu_barrier(struct rcu_state *rsp,
>  			while (cpu_is_offline(cpu) && ACCESS_ONCE(rdp->qlen))
>  				schedule_timeout_interruptible(1);
>  		} else if (ACCESS_ONCE(rdp->qlen)) {
> -			smp_call_function_single(cpu, rcu_barrier_func,
> -						 (void *)call_rcu_func, 1);
> +			smp_call_function_single(cpu, rcu_barrier_func, rsp, 1);
>  			preempt_enable();
>  		} else {
>  			preempt_enable();
> @@ -2367,7 +2364,7 @@ static void _rcu_barrier(struct rcu_state *rsp,
>  	raw_spin_unlock_irqrestore(&rsp->onofflock, flags);
>  	atomic_inc(&rcu_barrier_cpu_count);
>  	smp_mb__after_atomic_inc(); /* Ensure atomic_inc() before callback. */
> -	call_rcu_func(&rh, rcu_barrier_callback);
> +	rsp->call(&rh, rcu_barrier_callback);
>  
>  	/*
>  	 * Now that we have an rcu_barrier_callback() callback on each
> @@ -2390,7 +2387,7 @@ static void _rcu_barrier(struct rcu_state *rsp,
>   */
>  void rcu_barrier_bh(void)
>  {
> -	_rcu_barrier(&rcu_bh_state, call_rcu_bh);
> +	_rcu_barrier(&rcu_bh_state);
>  }
>  EXPORT_SYMBOL_GPL(rcu_barrier_bh);
>  
> @@ -2399,7 +2396,7 @@ EXPORT_SYMBOL_GPL(rcu_barrier_bh);
>   */
>  void rcu_barrier_sched(void)
>  {
> -	_rcu_barrier(&rcu_sched_state, call_rcu_sched);
> +	_rcu_barrier(&rcu_sched_state);
>  }
>  EXPORT_SYMBOL_GPL(rcu_barrier_sched);
>  
> diff --git a/kernel/rcutree.h b/kernel/rcutree.h
> index df3c2c8..15837d7 100644
> --- a/kernel/rcutree.h
> +++ b/kernel/rcutree.h
> @@ -350,6 +350,8 @@ struct rcu_state {
>  	u32 levelcnt[MAX_RCU_LVLS + 1];		/* # nodes in each level. */
>  	u8 levelspread[RCU_NUM_LVLS];		/* kids/node in each level. */
>  	struct rcu_data __percpu *rda;		/* pointer of percu rcu_data. */
> +	void (*call)(struct rcu_head *head,	/* call_rcu() flavor. */
> +		     void (*func)(struct rcu_head *head));
>  
>  	/* The following fields are guarded by the root rcu_node's lock. */
>  
> diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
> index 7cb86ae..6888706 100644
> --- a/kernel/rcutree_plugin.h
> +++ b/kernel/rcutree_plugin.h
> @@ -78,7 +78,8 @@ static void __init rcu_bootup_announce_oddness(void)
>  
>  #ifdef CONFIG_TREE_PREEMPT_RCU
>  
> -struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt);
> +struct rcu_state rcu_preempt_state =
> +	RCU_STATE_INITIALIZER(rcu_preempt, call_rcu);
>  DEFINE_PER_CPU(struct rcu_data, rcu_preempt_data);
>  static struct rcu_state *rcu_state = &rcu_preempt_state;
>  
> @@ -944,7 +945,7 @@ static int rcu_preempt_cpu_has_callbacks(int cpu)
>   */
>  void rcu_barrier(void)
>  {
> -	_rcu_barrier(&rcu_preempt_state, call_rcu);
> +	_rcu_barrier(&rcu_preempt_state);
>  }
>  EXPORT_SYMBOL_GPL(rcu_barrier);
>  
> -- 
> 1.7.8
>
diff mbox

Patch

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 8ce1b1d..8b3ab4e 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -62,8 +62,9 @@ 
 
 static struct lock_class_key rcu_node_class[RCU_NUM_LVLS];
 
-#define RCU_STATE_INITIALIZER(sname) { \
+#define RCU_STATE_INITIALIZER(sname, cr) { \
 	.level = { &sname##_state.node[0] }, \
+	.call = cr, \
 	.fqs_state = RCU_GP_IDLE, \
 	.gpnum = -300, \
 	.completed = -300, \
@@ -76,10 +77,11 @@  static struct lock_class_key rcu_node_class[RCU_NUM_LVLS];
 	.name = #sname, \
 }
 
-struct rcu_state rcu_sched_state = RCU_STATE_INITIALIZER(rcu_sched);
+struct rcu_state rcu_sched_state =
+	RCU_STATE_INITIALIZER(rcu_sched, call_rcu_sched);
 DEFINE_PER_CPU(struct rcu_data, rcu_sched_data);
 
-struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh);
+struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh, call_rcu_bh);
 DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
 
 static struct rcu_state *rcu_state;
@@ -2279,21 +2281,17 @@  static void rcu_barrier_func(void *type)
 {
 	int cpu = smp_processor_id();
 	struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu);
-	void (*call_rcu_func)(struct rcu_head *head,
-			      void (*func)(struct rcu_head *head));
+	struct rcu_state *rsp = type;
 
 	atomic_inc(&rcu_barrier_cpu_count);
-	call_rcu_func = type;
-	call_rcu_func(head, rcu_barrier_callback);
+	rsp->call(head, rcu_barrier_callback);
 }
 
 /*
  * Orchestrate the specified type of RCU barrier, waiting for all
  * RCU callbacks of the specified type to complete.
  */
-static void _rcu_barrier(struct rcu_state *rsp,
-			 void (*call_rcu_func)(struct rcu_head *head,
-					       void (*func)(struct rcu_head *head)))
+static void _rcu_barrier(struct rcu_state *rsp)
 {
 	int cpu;
 	unsigned long flags;
@@ -2345,8 +2343,7 @@  static void _rcu_barrier(struct rcu_state *rsp,
 			while (cpu_is_offline(cpu) && ACCESS_ONCE(rdp->qlen))
 				schedule_timeout_interruptible(1);
 		} else if (ACCESS_ONCE(rdp->qlen)) {
-			smp_call_function_single(cpu, rcu_barrier_func,
-						 (void *)call_rcu_func, 1);
+			smp_call_function_single(cpu, rcu_barrier_func, rsp, 1);
 			preempt_enable();
 		} else {
 			preempt_enable();
@@ -2367,7 +2364,7 @@  static void _rcu_barrier(struct rcu_state *rsp,
 	raw_spin_unlock_irqrestore(&rsp->onofflock, flags);
 	atomic_inc(&rcu_barrier_cpu_count);
 	smp_mb__after_atomic_inc(); /* Ensure atomic_inc() before callback. */
-	call_rcu_func(&rh, rcu_barrier_callback);
+	rsp->call(&rh, rcu_barrier_callback);
 
 	/*
 	 * Now that we have an rcu_barrier_callback() callback on each
@@ -2390,7 +2387,7 @@  static void _rcu_barrier(struct rcu_state *rsp,
  */
 void rcu_barrier_bh(void)
 {
-	_rcu_barrier(&rcu_bh_state, call_rcu_bh);
+	_rcu_barrier(&rcu_bh_state);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier_bh);
 
@@ -2399,7 +2396,7 @@  EXPORT_SYMBOL_GPL(rcu_barrier_bh);
  */
 void rcu_barrier_sched(void)
 {
-	_rcu_barrier(&rcu_sched_state, call_rcu_sched);
+	_rcu_barrier(&rcu_sched_state);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier_sched);
 
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index df3c2c8..15837d7 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -350,6 +350,8 @@  struct rcu_state {
 	u32 levelcnt[MAX_RCU_LVLS + 1];		/* # nodes in each level. */
 	u8 levelspread[RCU_NUM_LVLS];		/* kids/node in each level. */
 	struct rcu_data __percpu *rda;		/* pointer of percu rcu_data. */
+	void (*call)(struct rcu_head *head,	/* call_rcu() flavor. */
+		     void (*func)(struct rcu_head *head));
 
 	/* The following fields are guarded by the root rcu_node's lock. */
 
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 7cb86ae..6888706 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -78,7 +78,8 @@  static void __init rcu_bootup_announce_oddness(void)
 
 #ifdef CONFIG_TREE_PREEMPT_RCU
 
-struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt);
+struct rcu_state rcu_preempt_state =
+	RCU_STATE_INITIALIZER(rcu_preempt, call_rcu);
 DEFINE_PER_CPU(struct rcu_data, rcu_preempt_data);
 static struct rcu_state *rcu_state = &rcu_preempt_state;
 
@@ -944,7 +945,7 @@  static int rcu_preempt_cpu_has_callbacks(int cpu)
  */
 void rcu_barrier(void)
 {
-	_rcu_barrier(&rcu_preempt_state, call_rcu);
+	_rcu_barrier(&rcu_preempt_state);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier);