plist: Remove the need to supply locks to plist heads

This was legacy code brought over from the RT tree and
is no longer necessary.

Signed-off-by: Dima Zavin <dima@android.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Walker <dwalker@codeaurora.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/1310084879-10351-2-git-send-email-dima@android.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

8 files changed, 14 insertions, 68 deletions

diff --git a/include/linux/plist.h b/include/linux/plist.h
index c9b9f322c8d8..aa0fb390bd29 100644
--- a/include/linux/plist.h
+++ b/include/linux/plist.h
@@ -77,14 +77,9 @@
 
 #include <linux/kernel.h>
 #include <linux/list.h>
-#include <linux/spinlock_types.h>
 
 struct plist_head {
         struct list_head node_list;
-#ifdef CONFIG_DEBUG_PI_LIST
-        raw_spinlock_t *rawlock;
-        spinlock_t *spinlock;
-#endif
 };
 
 struct plist_node {
@@ -93,37 +88,13 @@ struct plist_node {
         struct list_head        node_list;
 };
 
-#ifdef CONFIG_DEBUG_PI_LIST
-# define PLIST_HEAD_LOCK_INIT(_lock)            .spinlock = _lock
-# define PLIST_HEAD_LOCK_INIT_RAW(_lock)        .rawlock = _lock
-#else
-# define PLIST_HEAD_LOCK_INIT(_lock)
-# define PLIST_HEAD_LOCK_INIT_RAW(_lock)
-#endif
-
-#define _PLIST_HEAD_INIT(head)                          \
-        .node_list = LIST_HEAD_INIT((head).node_list)
-
 /**
  * PLIST_HEAD_INIT - static struct plist_head initializer
  * @head:       struct plist_head variable name
- * @_lock:      lock to initialize for this list
- */
-#define PLIST_HEAD_INIT(head, _lock)                    \
-{                                                       \
-        _PLIST_HEAD_INIT(head),                         \
-        PLIST_HEAD_LOCK_INIT(&(_lock))                  \
-}
-
-/**
- * PLIST_HEAD_INIT_RAW - static struct plist_head initializer
- * @head:       struct plist_head variable name
- * @_lock:      lock to initialize for this list
  */
-#define PLIST_HEAD_INIT_RAW(head, _lock)                \
+#define PLIST_HEAD_INIT(head)                           \
 {                                                       \
-        _PLIST_HEAD_INIT(head),                         \
-        PLIST_HEAD_LOCK_INIT_RAW(&(_lock))              \
+        .node_list = LIST_HEAD_INIT((head).node_list)   \
 }
 
 /**
@@ -141,31 +112,11 @@ struct plist_node {
 /**
  * plist_head_init - dynamic struct plist_head initializer
  * @head:       &struct plist_head pointer
- * @lock:       spinlock protecting the list (debugging)
  */
 static inline void
-plist_head_init(struct plist_head *head, spinlock_t *lock)
+plist_head_init(struct plist_head *head)
 {
         INIT_LIST_HEAD(&head->node_list);
-#ifdef CONFIG_DEBUG_PI_LIST
-        head->spinlock = lock;
-        head->rawlock = NULL;
-#endif
-}
-
-/**
- * plist_head_init_raw - dynamic struct plist_head initializer
- * @head:       &struct plist_head pointer
- * @lock:       raw_spinlock protecting the list (debugging)
- */
-static inline void
-plist_head_init_raw(struct plist_head *head, raw_spinlock_t *lock)
-{
-        INIT_LIST_HEAD(&head->node_list);
-#ifdef CONFIG_DEBUG_PI_LIST
-        head->rawlock = lock;
-        head->spinlock = NULL;
-#endif
 }
 
 /**
diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 8d522ffeda33..de17134244f3 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -66,7 +66,7 @@ struct hrtimer_sleeper;
 
 #define __RT_MUTEX_INITIALIZER(mutexname) \
         { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
-        , .wait_list = PLIST_HEAD_INIT_RAW(mutexname.wait_list, mutexname.wait_lock) \
+        , .wait_list = PLIST_HEAD_INIT(mutexname.wait_list) \
         , .owner = NULL \
         __DEBUG_RT_MUTEX_INITIALIZER(mutexname)}
 
@@ -100,7 +100,7 @@ extern void rt_mutex_unlock(struct rt_mutex *lock);
 
 #ifdef CONFIG_RT_MUTEXES
 # define INIT_RT_MUTEXES(tsk)                                           \
-        .pi_waiters     = PLIST_HEAD_INIT(tsk.pi_waiters, tsk.pi_lock), \
+        .pi_waiters     = PLIST_HEAD_INIT(tsk.pi_waiters),      \
         INIT_RT_MUTEX_DEBUG(tsk)
 #else
 # define INIT_RT_MUTEXES(tsk)
diff --git a/kernel/fork.c b/kernel/fork.c
index 0276c30401a0..7517a53d50e3 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1013,7 +1013,7 @@ static void rt_mutex_init_task(struct task_struct *p)
 {
         raw_spin_lock_init(&p->pi_lock);
 #ifdef CONFIG_RT_MUTEXES
-        plist_head_init_raw(&p->pi_waiters, &p->pi_lock);
+        plist_head_init(&p->pi_waiters);
         p->pi_blocked_on = NULL;
 #endif
 }
diff --git a/kernel/futex.c b/kernel/futex.c
index fe28dc282eae..3fbc76cbb9aa 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2697,7 +2697,7 @@ static int __init futex_init(void)
                 futex_cmpxchg_enabled = 1;
 
         for (i = 0; i < ARRAY_SIZE(futex_queues); i++) {
-                plist_head_init(&futex_queues[i].chain, &futex_queues[i].lock);
+                plist_head_init(&futex_queues[i].chain);
                 spin_lock_init(&futex_queues[i].lock);
         }
 
diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index 6824ca7d4d0c..37f05d0f0793 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -74,7 +74,7 @@ static DEFINE_SPINLOCK(pm_qos_lock);
 static struct pm_qos_object null_pm_qos;
 static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier);
 static struct pm_qos_object cpu_dma_pm_qos = {
-        .requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests, pm_qos_lock),
+        .requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests),
         .notifiers = &cpu_dma_lat_notifier,
         .name = "cpu_dma_latency",
         .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
@@ -84,7 +84,7 @@ static struct pm_qos_object cpu_dma_pm_qos = {
 
 static BLOCKING_NOTIFIER_HEAD(network_lat_notifier);
 static struct pm_qos_object network_lat_pm_qos = {
-        .requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests, pm_qos_lock),
+        .requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests),
         .notifiers = &network_lat_notifier,
         .name = "network_latency",
         .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
@@ -95,7 +95,7 @@ static struct pm_qos_object network_lat_pm_qos = {
 
 static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier);
 static struct pm_qos_object network_throughput_pm_qos = {
-        .requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests, pm_qos_lock),
+        .requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests),
         .notifiers = &network_throughput_notifier,
         .name = "network_throughput",
         .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c
index ab449117aaf2..255e1662acdb 100644
--- a/kernel/rtmutex.c
+++ b/kernel/rtmutex.c
@@ -890,7 +890,7 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name)
 {
         lock->owner = NULL;
         raw_spin_lock_init(&lock->wait_lock);
-        plist_head_init_raw(&lock->wait_list, &lock->wait_lock);
+        plist_head_init(&lock->wait_list);
 
         debug_rt_mutex_init(lock, name);
 }
diff --git a/kernel/sched.c b/kernel/sched.c
index 3f2e502d609b..71bc127e96ba 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -7781,7 +7781,7 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
 #ifdef CONFIG_SMP
         rt_rq->rt_nr_migratory = 0;
         rt_rq->overloaded = 0;
-        plist_head_init_raw(&rt_rq->pushable_tasks, &rq->lock);
+        plist_head_init(&rt_rq->pushable_tasks);
 #endif
 
         rt_rq->rt_time = 0;
@@ -7986,7 +7986,7 @@ void __init sched_init(void)
 #endif
 
 #ifdef CONFIG_RT_MUTEXES
-        plist_head_init_raw(&init_task.pi_waiters, &init_task.pi_lock);
+        plist_head_init(&init_task.pi_waiters);
 #endif
 
         /*
diff --git a/lib/plist.c b/lib/plist.c
index 0ae7e6431726..a0a4da489c22 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -56,11 +56,6 @@ static void plist_check_list(struct list_head *top)
 
 static void plist_check_head(struct plist_head *head)
 {
-        WARN_ON(head != &test_head && !head->rawlock && !head->spinlock);
-        if (head->rawlock)
-                WARN_ON_SMP(!raw_spin_is_locked(head->rawlock));
-        if (head->spinlock)
-                WARN_ON_SMP(!spin_is_locked(head->spinlock));
         if (!plist_head_empty(head))
                 plist_check_list(&plist_first(head)->prio_list);
         plist_check_list(&head->node_list);
@@ -180,7 +175,7 @@ static int  __init plist_test(void)
         unsigned int r = local_clock();
 
         printk(KERN_INFO "start plist test\n");
-        plist_head_init(&test_head, NULL);
+        plist_head_init(&test_head);
         for (i = 0; i < ARRAY_SIZE(test_node); i++)
                 plist_node_init(test_node + i, 0);