Merge commit 'v2.6.29-rc7' into perfcounters/core
[linux-2.6.git] / kernel / spinlock.c
index e15ed17..29ab207 100644 (file)
@@ -3,32 +3,31 @@
  *
  * Author: Zwane Mwaikambo <zwane@fsmlabs.com>
  *
- * Copyright (2004) Ingo Molnar
+ * Copyright (2004, 2005) Ingo Molnar
+ *
+ * This file contains the spinlock/rwlock implementations for the
+ * SMP and the DEBUG_SPINLOCK cases. (UP-nondebug inlines them)
+ *
+ * Note that some architectures have special knowledge about the
+ * stack frames of these functions in their profile_pc. If you
+ * change anything significant here that could change the stack
+ * frame contact the architecture maintainers.
  */
 
-#include <linux/config.h>
 #include <linux/linkage.h>
 #include <linux/preempt.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
+#include <linux/debug_locks.h>
 #include <linux/module.h>
 
-/*
- * Generic declaration of the raw read_trylock() function,
- * architectures are supposed to optimize this:
- */
-int __lockfunc generic_raw_read_trylock(rwlock_t *lock)
-{
-       _raw_read_lock(lock);
-       return 1;
-}
-EXPORT_SYMBOL(generic_raw_read_trylock);
-
 int __lockfunc _spin_trylock(spinlock_t *lock)
 {
        preempt_disable();
-       if (_raw_spin_trylock(lock))
+       if (_raw_spin_trylock(lock)) {
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
                return 1;
+       }
        
        preempt_enable();
        return 0;
@@ -38,8 +37,10 @@ EXPORT_SYMBOL(_spin_trylock);
 int __lockfunc _read_trylock(rwlock_t *lock)
 {
        preempt_disable();
-       if (_raw_read_trylock(lock))
+       if (_raw_read_trylock(lock)) {
+               rwlock_acquire_read(&lock->dep_map, 0, 1, _RET_IP_);
                return 1;
+       }
 
        preempt_enable();
        return 0;
@@ -49,20 +50,28 @@ EXPORT_SYMBOL(_read_trylock);
 int __lockfunc _write_trylock(rwlock_t *lock)
 {
        preempt_disable();
-       if (_raw_write_trylock(lock))
+       if (_raw_write_trylock(lock)) {
+               rwlock_acquire(&lock->dep_map, 0, 1, _RET_IP_);
                return 1;
+       }
 
        preempt_enable();
        return 0;
 }
 EXPORT_SYMBOL(_write_trylock);
 
-#ifndef CONFIG_PREEMPT
+/*
+ * If lockdep is enabled then we use the non-preemption spin-ops
+ * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are
+ * not re-enabled during lock-acquire (which the preempt-spin-ops do):
+ */
+#if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)
 
 void __lockfunc _read_lock(rwlock_t *lock)
 {
        preempt_disable();
-       _raw_read_lock(lock);
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
 }
 EXPORT_SYMBOL(_read_lock);
 
@@ -72,7 +81,17 @@ unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)
 
        local_irq_save(flags);
        preempt_disable();
-       _raw_spin_lock_flags(lock, flags);
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       /*
+        * On lockdep we dont want the hand-coded irq-enable of
+        * _raw_spin_lock_flags() code, because lockdep assumes
+        * that interrupts are not re-enabled during lock-acquire:
+        */
+#ifdef CONFIG_LOCKDEP
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+#else
+       _raw_spin_lock_flags(lock, &flags);
+#endif
        return flags;
 }
 EXPORT_SYMBOL(_spin_lock_irqsave);
@@ -81,7 +100,8 @@ void __lockfunc _spin_lock_irq(spinlock_t *lock)
 {
        local_irq_disable();
        preempt_disable();
-       _raw_spin_lock(lock);
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
 }
 EXPORT_SYMBOL(_spin_lock_irq);
 
@@ -89,7 +109,8 @@ void __lockfunc _spin_lock_bh(spinlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
-       _raw_spin_lock(lock);
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
 }
 EXPORT_SYMBOL(_spin_lock_bh);
 
@@ -99,7 +120,8 @@ unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
 
        local_irq_save(flags);
        preempt_disable();
-       _raw_read_lock(lock);
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
        return flags;
 }
 EXPORT_SYMBOL(_read_lock_irqsave);
@@ -108,7 +130,8 @@ void __lockfunc _read_lock_irq(rwlock_t *lock)
 {
        local_irq_disable();
        preempt_disable();
-       _raw_read_lock(lock);
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
 }
 EXPORT_SYMBOL(_read_lock_irq);
 
@@ -116,7 +139,8 @@ void __lockfunc _read_lock_bh(rwlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
-       _raw_read_lock(lock);
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
 }
 EXPORT_SYMBOL(_read_lock_bh);
 
@@ -126,7 +150,8 @@ unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
 
        local_irq_save(flags);
        preempt_disable();
-       _raw_write_lock(lock);
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
        return flags;
 }
 EXPORT_SYMBOL(_write_lock_irqsave);
@@ -135,7 +160,8 @@ void __lockfunc _write_lock_irq(rwlock_t *lock)
 {
        local_irq_disable();
        preempt_disable();
-       _raw_write_lock(lock);
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
 }
 EXPORT_SYMBOL(_write_lock_irq);
 
@@ -143,14 +169,16 @@ void __lockfunc _write_lock_bh(rwlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
-       _raw_write_lock(lock);
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
 }
 EXPORT_SYMBOL(_write_lock_bh);
 
 void __lockfunc _spin_lock(spinlock_t *lock)
 {
        preempt_disable();
-       _raw_spin_lock(lock);
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
 }
 
 EXPORT_SYMBOL(_spin_lock);
@@ -158,7 +186,8 @@ EXPORT_SYMBOL(_spin_lock);
 void __lockfunc _write_lock(rwlock_t *lock)
 {
        preempt_disable();
-       _raw_write_lock(lock);
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
 }
 
 EXPORT_SYMBOL(_write_lock);
@@ -176,16 +205,16 @@ EXPORT_SYMBOL(_write_lock);
 #define BUILD_LOCK_OPS(op, locktype)                                   \
 void __lockfunc _##op##_lock(locktype##_t *lock)                       \
 {                                                                      \
-       preempt_disable();                                              \
        for (;;) {                                                      \
+               preempt_disable();                                      \
                if (likely(_raw_##op##_trylock(lock)))                  \
                        break;                                          \
                preempt_enable();                                       \
+                                                                       \
                if (!(lock)->break_lock)                                \
                        (lock)->break_lock = 1;                         \
                while (!op##_can_lock(lock) && (lock)->break_lock)      \
-                       cpu_relax();                                    \
-               preempt_disable();                                      \
+                       _raw_##op##_relax(&lock->raw_lock);             \
        }                                                               \
        (lock)->break_lock = 0;                                         \
 }                                                                      \
@@ -196,19 +225,18 @@ unsigned long __lockfunc _##op##_lock_irqsave(locktype##_t *lock) \
 {                                                                      \
        unsigned long flags;                                            \
                                                                        \
-       preempt_disable();                                              \
        for (;;) {                                                      \
+               preempt_disable();                                      \
                local_irq_save(flags);                                  \
                if (likely(_raw_##op##_trylock(lock)))                  \
                        break;                                          \
                local_irq_restore(flags);                               \
-                                                                       \
                preempt_enable();                                       \
+                                                                       \
                if (!(lock)->break_lock)                                \
                        (lock)->break_lock = 1;                         \
                while (!op##_can_lock(lock) && (lock)->break_lock)      \
-                       cpu_relax();                                    \
-               preempt_disable();                                      \
+                       _raw_##op##_relax(&lock->raw_lock);             \
        }                                                               \
        (lock)->break_lock = 0;                                         \
        return flags;                                                   \
@@ -254,8 +282,51 @@ BUILD_LOCK_OPS(write, rwlock);
 
 #endif /* CONFIG_PREEMPT */
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass)
+{
+       preempt_disable();
+       spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+}
+EXPORT_SYMBOL(_spin_lock_nested);
+
+unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclass)
+{
+       unsigned long flags;
+
+       local_irq_save(flags);
+       preempt_disable();
+       spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+       /*
+        * On lockdep we dont want the hand-coded irq-enable of
+        * _raw_spin_lock_flags() code, because lockdep assumes
+        * that interrupts are not re-enabled during lock-acquire:
+        */
+#ifdef CONFIG_LOCKDEP
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+#else
+       _raw_spin_lock_flags(lock, &flags);
+#endif
+       return flags;
+}
+EXPORT_SYMBOL(_spin_lock_irqsave_nested);
+
+void __lockfunc _spin_lock_nest_lock(spinlock_t *lock,
+                                    struct lockdep_map *nest_lock)
+{
+       preempt_disable();
+       spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
+       LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
+}
+EXPORT_SYMBOL(_spin_lock_nest_lock);
+
+#endif
+
 void __lockfunc _spin_unlock(spinlock_t *lock)
 {
+       spin_release(&lock->dep_map, 1, _RET_IP_);
        _raw_spin_unlock(lock);
        preempt_enable();
 }
@@ -263,6 +334,7 @@ EXPORT_SYMBOL(_spin_unlock);
 
 void __lockfunc _write_unlock(rwlock_t *lock)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_write_unlock(lock);
        preempt_enable();
 }
@@ -270,6 +342,7 @@ EXPORT_SYMBOL(_write_unlock);
 
 void __lockfunc _read_unlock(rwlock_t *lock)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_read_unlock(lock);
        preempt_enable();
 }
@@ -277,6 +350,7 @@ EXPORT_SYMBOL(_read_unlock);
 
 void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
 {
+       spin_release(&lock->dep_map, 1, _RET_IP_);
        _raw_spin_unlock(lock);
        local_irq_restore(flags);
        preempt_enable();
@@ -285,6 +359,7 @@ EXPORT_SYMBOL(_spin_unlock_irqrestore);
 
 void __lockfunc _spin_unlock_irq(spinlock_t *lock)
 {
+       spin_release(&lock->dep_map, 1, _RET_IP_);
        _raw_spin_unlock(lock);
        local_irq_enable();
        preempt_enable();
@@ -293,14 +368,16 @@ EXPORT_SYMBOL(_spin_unlock_irq);
 
 void __lockfunc _spin_unlock_bh(spinlock_t *lock)
 {
+       spin_release(&lock->dep_map, 1, _RET_IP_);
        _raw_spin_unlock(lock);
-       preempt_enable();
-       local_bh_enable();
+       preempt_enable_no_resched();
+       local_bh_enable_ip((unsigned long)__builtin_return_address(0));
 }
 EXPORT_SYMBOL(_spin_unlock_bh);
 
 void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_read_unlock(lock);
        local_irq_restore(flags);
        preempt_enable();
@@ -309,6 +386,7 @@ EXPORT_SYMBOL(_read_unlock_irqrestore);
 
 void __lockfunc _read_unlock_irq(rwlock_t *lock)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_read_unlock(lock);
        local_irq_enable();
        preempt_enable();
@@ -317,14 +395,16 @@ EXPORT_SYMBOL(_read_unlock_irq);
 
 void __lockfunc _read_unlock_bh(rwlock_t *lock)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_read_unlock(lock);
-       preempt_enable();
-       local_bh_enable();
+       preempt_enable_no_resched();
+       local_bh_enable_ip((unsigned long)__builtin_return_address(0));
 }
 EXPORT_SYMBOL(_read_unlock_bh);
 
 void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_write_unlock(lock);
        local_irq_restore(flags);
        preempt_enable();
@@ -333,6 +413,7 @@ EXPORT_SYMBOL(_write_unlock_irqrestore);
 
 void __lockfunc _write_unlock_irq(rwlock_t *lock)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_write_unlock(lock);
        local_irq_enable();
        preempt_enable();
@@ -341,9 +422,10 @@ EXPORT_SYMBOL(_write_unlock_irq);
 
 void __lockfunc _write_unlock_bh(rwlock_t *lock)
 {
+       rwlock_release(&lock->dep_map, 1, _RET_IP_);
        _raw_write_unlock(lock);
-       preempt_enable();
-       local_bh_enable();
+       preempt_enable_no_resched();
+       local_bh_enable_ip((unsigned long)__builtin_return_address(0));
 }
 EXPORT_SYMBOL(_write_unlock_bh);
 
@@ -351,16 +433,18 @@ int __lockfunc _spin_trylock_bh(spinlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
-       if (_raw_spin_trylock(lock))
+       if (_raw_spin_trylock(lock)) {
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
                return 1;
+       }
 
-       preempt_enable();
-       local_bh_enable();
+       preempt_enable_no_resched();
+       local_bh_enable_ip((unsigned long)__builtin_return_address(0));
        return 0;
 }
 EXPORT_SYMBOL(_spin_trylock_bh);
 
-int in_lock_functions(unsigned long addr)
+notrace int in_lock_functions(unsigned long addr)
 {
        /* Linker adds these: start and end of __lockfunc functions */
        extern char __lock_text_start[], __lock_text_end[];