From 4e87b2d7e887df3fe251dd7f702591a3acf369ca Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Sat, 13 Oct 2012 01:14:14 +0800 Subject: srcu: Credit Lai Jiangshan with SRCU rewrite Lai Jiangshan rewrote SRCU, so this commit ensures that he gets his proper share of blame^Wcredit. Signed-off-by: Lai Jiangshan Signed-off-by: Paul E. McKenney --- include/linux/srcu.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/srcu.h') diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 55a5c52cbb25..a55ddb19053c 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 + * Lai Jiangshan * * For detailed explanation of Read-Copy Update mechanism see - * Documentation/RCU/ *.txt -- cgit v1.2.3 From f2ebfbc991044fd5b89d4529741d7500feb37fbd Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Sat, 13 Oct 2012 01:14:15 +0800 Subject: srcu: Export process_srcu() 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 Signed-off-by: Paul E. McKenney --- include/linux/srcu.h | 2 ++ kernel/srcu.c | 6 ++---- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'include/linux/srcu.h') diff --git a/include/linux/srcu.h b/include/linux/srcu.h index a55ddb19053c..5cce128f196c 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 0b99f27fa2f7..b363b0924561 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); -- cgit v1.2.3 From 55c6659afaa6fd79a3b5a7c2b42bb87e0c11209d Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Sat, 13 Oct 2012 01:14:16 +0800 Subject: srcu: Add DEFINE_SRCU() 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 Signed-off-by: Paul E. McKenney [ paulmck: Updated for __DELAYED_WORK_INITIALIZER() added argument, fixed whitespace issue. ] --- include/linux/srcu.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'include/linux/srcu.h') diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 5cce128f196c..6eb691b08358 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 -- cgit v1.2.3