[PATCH tip/core/rcu 0/4] SRCU changes for 3.8

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* [PATCH tip/core/rcu 0/4] SRCU changes for 3.8
@ 2012-10-30 16:36 Paul E. McKenney
  2012-10-30 16:38 ` [PATCH tip/core/rcu 1/4] srcu: Credit Lai Jiangshan with SRCU rewrite Paul E. McKenney
  0 siblings, 1 reply; 5+ messages in thread
From: Paul E. McKenney @ 2012-10-30 16:36 UTC (permalink / raw)
  To: linux-kernel
  Cc: mingo, laijs, dipankar, akpm, mathieu.desnoyers, josh, niv, tglx,
	peterz, rostedt, Valdis.Kletnieks, dhowells, edumazet, darren,
	fweisbec, sbw, patches

Hello!

This patch series contains SRCU changes allowing srcu_structs to be
statically initialized.  The patches are as follows:

1.	Add Lai Jiangshan as author for srcu.c and srcu.h.
	(Courtesy Lia Jiangshan.)
2.	Export process_srcu() so that the initialization macro may
	be invoked anywhere.  (Courtesy Lia Jiangshan.)
3.	Add DEFINE_SRCU().  (Courtesy Lia Jiangshan.)
4.	Add DEFINE_STATIC_SRCU().  This cannot be emulated by
	"static DEFINE_SRCU()" due to forward-reference issues.
	(Courtesy Lia Jiangshan.)

							Thanx, Paul

 b/include/linux/srcu.h |   34 ++++++++++++++++++++++++++++++++++
 b/kernel/rcutorture.c  |   41 ++++++-----------------------------------
 b/kernel/srcu.c        |    8 ++++----
 3 files changed, 44 insertions(+), 39 deletions(-)


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH tip/core/rcu 1/4] srcu: Credit Lai Jiangshan with SRCU rewrite
  2012-10-30 16:36 [PATCH tip/core/rcu 0/4] SRCU changes for 3.8 Paul E. McKenney
@ 2012-10-30 16:38 ` Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 2/4] srcu: Export process_srcu() Paul E. McKenney
                     ` (2 more replies)
  0 siblings, 3 replies; 5+ messages in thread
From: Paul E. McKenney @ 2012-10-30 16:38 UTC (permalink / raw)
  To: linux-kernel
  Cc: mingo, laijs, dipankar, akpm, mathieu.desnoyers, josh, niv, tglx,
	peterz, rostedt, Valdis.Kletnieks, dhowells, edumazet, darren,
	fweisbec, sbw, patches, Paul E. McKenney

From: Lai Jiangshan <laijs@cn.fujitsu.com>

Lai Jiangshan rewrote SRCU, so this commit ensures that he gets his
proper share of blame^Wcredit.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 include/linux/srcu.h |    2 ++
 kernel/srcu.c        |    2 ++
 2 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index 55a5c52..a55ddb1 100644
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -16,8 +16,10 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  *
  * Copyright (C) IBM Corporation, 2006
+ * Copyright (C) Fujitsu, 2012
  *
  * Author: Paul McKenney <paulmck@us.ibm.com>
+ *	   Lai Jiangshan <laijs@cn.fujitsu.com>
  *
  * For detailed explanation of Read-Copy Update mechanism see -
  * 		Documentation/RCU/ *.txt
diff --git a/kernel/srcu.c b/kernel/srcu.c
index 97c465e..0b99f27 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -16,8 +16,10 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  *
  * Copyright (C) IBM Corporation, 2006
+ * Copyright (C) Fujitsu, 2012
  *
  * Author: Paul McKenney <paulmck@us.ibm.com>
+ *	   Lai Jiangshan <laijs@cn.fujitsu.com>
  *
  * For detailed explanation of Read-Copy Update mechanism see -
  * 		Documentation/RCU/ *.txt
-- 
1.7.8


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH tip/core/rcu 2/4] srcu: Export process_srcu()
  2012-10-30 16:38 ` [PATCH tip/core/rcu 1/4] srcu: Credit Lai Jiangshan with SRCU rewrite Paul E. McKenney
@ 2012-10-30 16:38   ` Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 3/4] srcu: Add DEFINE_SRCU() Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 4/4] rcutorture: Use DEFINE_STATIC_SRCU() Paul E. McKenney
  2 siblings, 0 replies; 5+ messages in thread
From: Paul E. McKenney @ 2012-10-30 16:38 UTC (permalink / raw)
  To: linux-kernel
  Cc: mingo, laijs, dipankar, akpm, mathieu.desnoyers, josh, niv, tglx,
	peterz, rostedt, Valdis.Kletnieks, dhowells, edumazet, darren,
	fweisbec, sbw, patches, Paul E. McKenney

From: Lai Jiangshan <laijs@cn.fujitsu.com>

Because process_srcu() will be used in DEFINE_SRCU(), which is a macro
that could be expanded pretty much anywhere, it can no longer be static.
Note that process_srcu() is still internal to srcu.h.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 include/linux/srcu.h |    2 ++
 kernel/srcu.c        |    6 ++----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index a55ddb1..5cce128 100644
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -78,6 +78,8 @@ int init_srcu_struct(struct srcu_struct *sp);
 
 #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
+void process_srcu(struct work_struct *work);
+
 /**
  * call_srcu() - Queue a callback for invocation after an SRCU grace period
  * @sp: srcu_struct in queue the callback
diff --git a/kernel/srcu.c b/kernel/srcu.c
index 0b99f27..b363b09 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -94,9 +94,6 @@ static inline void rcu_batch_move(struct rcu_batch *to, struct rcu_batch *from)
 	}
 }
 
-/* single-thread state-machine */
-static void process_srcu(struct work_struct *work);
-
 static int init_srcu_struct_fields(struct srcu_struct *sp)
 {
 	sp->completed = 0;
@@ -639,7 +636,7 @@ static void srcu_reschedule(struct srcu_struct *sp)
 /*
  * This is the work-queue function that handles SRCU grace periods.
  */
-static void process_srcu(struct work_struct *work)
+void process_srcu(struct work_struct *work)
 {
 	struct srcu_struct *sp;
 
@@ -650,3 +647,4 @@ static void process_srcu(struct work_struct *work)
 	srcu_invoke_callbacks(sp);
 	srcu_reschedule(sp);
 }
+EXPORT_SYMBOL_GPL(process_srcu);
-- 
1.7.8


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH tip/core/rcu 3/4] srcu: Add DEFINE_SRCU()
  2012-10-30 16:38 ` [PATCH tip/core/rcu 1/4] srcu: Credit Lai Jiangshan with SRCU rewrite Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 2/4] srcu: Export process_srcu() Paul E. McKenney
@ 2012-10-30 16:38   ` Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 4/4] rcutorture: Use DEFINE_STATIC_SRCU() Paul E. McKenney
  2 siblings, 0 replies; 5+ messages in thread
From: Paul E. McKenney @ 2012-10-30 16:38 UTC (permalink / raw)
  To: linux-kernel
  Cc: mingo, laijs, dipankar, akpm, mathieu.desnoyers, josh, niv, tglx,
	peterz, rostedt, Valdis.Kletnieks, dhowells, edumazet, darren,
	fweisbec, sbw, patches, Paul E. McKenney

From: Lai Jiangshan <laijs@cn.fujitsu.com>

In old days, we had two different API sets for dynamic-allocated per-CPU
data and DEFINE_PER_CPU()-defined per_cpu data, and because SRCU used
dynamic-allocated per-CPU data, its srcu_struct structures cannot be
declared statically.  This commit therefore introduces DEFINE_SRCU()
and DEFINE_STATIC_SRCU() to allow statically declared SRCU structures,
using the new static per-CPU interfaces.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Updated for __DELAYED_WORK_INITIALIZER() added argument,
	   fixed whitespace issue. ]
---
 include/linux/srcu.h |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index 5cce128..6eb691b 100644
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -42,6 +42,8 @@ struct rcu_batch {
 	struct rcu_head *head, **tail;
 };
 
+#define RCU_BATCH_INIT(name) { NULL, &(name.head) }
+
 struct srcu_struct {
 	unsigned completed;
 	struct srcu_struct_array __percpu *per_cpu_ref;
@@ -72,14 +74,42 @@ int __init_srcu_struct(struct srcu_struct *sp, const char *name,
 	__init_srcu_struct((sp), #sp, &__srcu_key); \
 })
 
+#define __SRCU_DEP_MAP_INIT(srcu_name)	.dep_map = { .name = #srcu_name },
 #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
 int init_srcu_struct(struct srcu_struct *sp);
 
+#define __SRCU_DEP_MAP_INIT(srcu_name)
 #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
 void process_srcu(struct work_struct *work);
 
+#define __SRCU_STRUCT_INIT(name)					\
+	{								\
+		.completed = -300,					\
+		.per_cpu_ref = &name##_srcu_array,			\
+		.queue_lock = __SPIN_LOCK_UNLOCKED(name.queue_lock),	\
+		.running = false,					\
+		.batch_queue = RCU_BATCH_INIT(name.batch_queue),	\
+		.batch_check0 = RCU_BATCH_INIT(name.batch_check0),	\
+		.batch_check1 = RCU_BATCH_INIT(name.batch_check1),	\
+		.batch_done = RCU_BATCH_INIT(name.batch_done),		\
+		.work = __DELAYED_WORK_INITIALIZER(name.work, process_srcu, 0),\
+		__SRCU_DEP_MAP_INIT(name)				\
+	}
+
+/*
+ * define and init a srcu struct at build time.
+ * dont't call init_srcu_struct() nor cleanup_srcu_struct() on it.
+ */
+#define DEFINE_SRCU(name)						\
+	static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\
+	struct srcu_struct name = __SRCU_STRUCT_INIT(name);
+
+#define DEFINE_STATIC_SRCU(name)					\
+	static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\
+	static struct srcu_struct name = __SRCU_STRUCT_INIT(name);
+
 /**
  * call_srcu() - Queue a callback for invocation after an SRCU grace period
  * @sp: srcu_struct in queue the callback
-- 
1.7.8


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH tip/core/rcu 4/4] rcutorture: Use DEFINE_STATIC_SRCU()
  2012-10-30 16:38 ` [PATCH tip/core/rcu 1/4] srcu: Credit Lai Jiangshan with SRCU rewrite Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 2/4] srcu: Export process_srcu() Paul E. McKenney
  2012-10-30 16:38   ` [PATCH tip/core/rcu 3/4] srcu: Add DEFINE_SRCU() Paul E. McKenney
@ 2012-10-30 16:38   ` Paul E. McKenney
  2 siblings, 0 replies; 5+ messages in thread
From: Paul E. McKenney @ 2012-10-30 16:38 UTC (permalink / raw)
  To: linux-kernel
  Cc: mingo, laijs, dipankar, akpm, mathieu.desnoyers, josh, niv, tglx,
	peterz, rostedt, Valdis.Kletnieks, dhowells, edumazet, darren,
	fweisbec, sbw, patches, Paul E. McKenney

From: Lai Jiangshan <laijs@cn.fujitsu.com>

Use DEFINE_STATIC_SRCU() to simplify the rcutorture.c SRCU test code.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 kernel/rcutorture.c |   41 ++++++-----------------------------------
 1 files changed, 6 insertions(+), 35 deletions(-)

diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index aaa7b9f..f401972 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -339,7 +339,6 @@ rcu_stutter_wait(char *title)
 
 struct rcu_torture_ops {
 	void (*init)(void);
-	void (*cleanup)(void);
 	int (*readlock)(void);
 	void (*read_delay)(struct rcu_random_state *rrsp);
 	void (*readunlock)(int idx);
@@ -431,7 +430,6 @@ static void rcu_torture_deferred_free(struct rcu_torture *p)
 
 static struct rcu_torture_ops rcu_ops = {
 	.init		= NULL,
-	.cleanup	= NULL,
 	.readlock	= rcu_torture_read_lock,
 	.read_delay	= rcu_read_delay,
 	.readunlock	= rcu_torture_read_unlock,
@@ -475,7 +473,6 @@ static void rcu_sync_torture_init(void)
 
 static struct rcu_torture_ops rcu_sync_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= rcu_torture_read_lock,
 	.read_delay	= rcu_read_delay,
 	.readunlock	= rcu_torture_read_unlock,
@@ -493,7 +490,6 @@ static struct rcu_torture_ops rcu_sync_ops = {
 
 static struct rcu_torture_ops rcu_expedited_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= rcu_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= rcu_torture_read_unlock,
@@ -536,7 +532,6 @@ static void rcu_bh_torture_deferred_free(struct rcu_torture *p)
 
 static struct rcu_torture_ops rcu_bh_ops = {
 	.init		= NULL,
-	.cleanup	= NULL,
 	.readlock	= rcu_bh_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= rcu_bh_torture_read_unlock,
@@ -553,7 +548,6 @@ static struct rcu_torture_ops rcu_bh_ops = {
 
 static struct rcu_torture_ops rcu_bh_sync_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= rcu_bh_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= rcu_bh_torture_read_unlock,
@@ -570,7 +564,6 @@ static struct rcu_torture_ops rcu_bh_sync_ops = {
 
 static struct rcu_torture_ops rcu_bh_expedited_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= rcu_bh_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= rcu_bh_torture_read_unlock,
@@ -589,19 +582,7 @@ static struct rcu_torture_ops rcu_bh_expedited_ops = {
  * Definitions for srcu torture testing.
  */
 
-static struct srcu_struct srcu_ctl;
-
-static void srcu_torture_init(void)
-{
-	init_srcu_struct(&srcu_ctl);
-	rcu_sync_torture_init();
-}
-
-static void srcu_torture_cleanup(void)
-{
-	synchronize_srcu(&srcu_ctl);
-	cleanup_srcu_struct(&srcu_ctl);
-}
+DEFINE_STATIC_SRCU(srcu_ctl);
 
 static int srcu_torture_read_lock(void) __acquires(&srcu_ctl)
 {
@@ -672,8 +653,7 @@ static int srcu_torture_stats(char *page)
 }
 
 static struct rcu_torture_ops srcu_ops = {
-	.init		= srcu_torture_init,
-	.cleanup	= srcu_torture_cleanup,
+	.init		= rcu_sync_torture_init,
 	.readlock	= srcu_torture_read_lock,
 	.read_delay	= srcu_read_delay,
 	.readunlock	= srcu_torture_read_unlock,
@@ -687,8 +667,7 @@ static struct rcu_torture_ops srcu_ops = {
 };
 
 static struct rcu_torture_ops srcu_sync_ops = {
-	.init		= srcu_torture_init,
-	.cleanup	= srcu_torture_cleanup,
+	.init		= rcu_sync_torture_init,
 	.readlock	= srcu_torture_read_lock,
 	.read_delay	= srcu_read_delay,
 	.readunlock	= srcu_torture_read_unlock,
@@ -712,8 +691,7 @@ static void srcu_torture_read_unlock_raw(int idx) __releases(&srcu_ctl)
 }
 
 static struct rcu_torture_ops srcu_raw_ops = {
-	.init		= srcu_torture_init,
-	.cleanup	= srcu_torture_cleanup,
+	.init		= rcu_sync_torture_init,
 	.readlock	= srcu_torture_read_lock_raw,
 	.read_delay	= srcu_read_delay,
 	.readunlock	= srcu_torture_read_unlock_raw,
@@ -727,8 +705,7 @@ static struct rcu_torture_ops srcu_raw_ops = {
 };
 
 static struct rcu_torture_ops srcu_raw_sync_ops = {
-	.init		= srcu_torture_init,
-	.cleanup	= srcu_torture_cleanup,
+	.init		= rcu_sync_torture_init,
 	.readlock	= srcu_torture_read_lock_raw,
 	.read_delay	= srcu_read_delay,
 	.readunlock	= srcu_torture_read_unlock_raw,
@@ -747,8 +724,7 @@ static void srcu_torture_synchronize_expedited(void)
 }
 
 static struct rcu_torture_ops srcu_expedited_ops = {
-	.init		= srcu_torture_init,
-	.cleanup	= srcu_torture_cleanup,
+	.init		= rcu_sync_torture_init,
 	.readlock	= srcu_torture_read_lock,
 	.read_delay	= srcu_read_delay,
 	.readunlock	= srcu_torture_read_unlock,
@@ -783,7 +759,6 @@ static void rcu_sched_torture_deferred_free(struct rcu_torture *p)
 
 static struct rcu_torture_ops sched_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= sched_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= sched_torture_read_unlock,
@@ -799,7 +774,6 @@ static struct rcu_torture_ops sched_ops = {
 
 static struct rcu_torture_ops sched_sync_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= sched_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= sched_torture_read_unlock,
@@ -814,7 +788,6 @@ static struct rcu_torture_ops sched_sync_ops = {
 
 static struct rcu_torture_ops sched_expedited_ops = {
 	.init		= rcu_sync_torture_init,
-	.cleanup	= NULL,
 	.readlock	= sched_torture_read_lock,
 	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
 	.readunlock	= sched_torture_read_unlock,
@@ -1936,8 +1909,6 @@ rcu_torture_cleanup(void)
 
 	rcu_torture_stats_print();  /* -After- the stats thread is stopped! */
 
-	if (cur_ops->cleanup)
-		cur_ops->cleanup();
 	if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error)
 		rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE");
 	else if (n_online_successes != n_online_attempts ||
-- 
1.7.8


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2012-10-30 16:40 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-10-30 16:36 [PATCH tip/core/rcu 0/4] SRCU changes for 3.8 Paul E. McKenney
2012-10-30 16:38 ` [PATCH tip/core/rcu 1/4] srcu: Credit Lai Jiangshan with SRCU rewrite Paul E. McKenney
2012-10-30 16:38   ` [PATCH tip/core/rcu 2/4] srcu: Export process_srcu() Paul E. McKenney
2012-10-30 16:38   ` [PATCH tip/core/rcu 3/4] srcu: Add DEFINE_SRCU() Paul E. McKenney
2012-10-30 16:38   ` [PATCH tip/core/rcu 4/4] rcutorture: Use DEFINE_STATIC_SRCU() Paul E. McKenney

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