[PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks

[linux.git] / kernel / spinlock.c

diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index d1b810782bc4e1b643faac72733074e2dc492fa4..476c3741511b31af1717f90e052880e0e6c9b585 100644 (file)
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -7,31 +7,27 @@
  *
  * 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(raw_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;
@@ -41,8 +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;
@@ -52,19 +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);
 
-#if !defined(CONFIG_PREEMPT) || !defined(CONFIG_SMP)
+/*
+ * 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_PREEMPT) || !defined(CONFIG_SMP) || \
+       defined(CONFIG_DEBUG_LOCK_ALLOC)
 
 void __lockfunc _read_lock(rwlock_t *lock)
 {
        preempt_disable();
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_read_lock(lock);
 }
 EXPORT_SYMBOL(_read_lock);
@@ -75,7 +82,17 @@ unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)
 
        local_irq_save(flags);
        preempt_disable();
+       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_PROVE_LOCKING
+       _raw_spin_lock(lock);
+#else
        _raw_spin_lock_flags(lock, &flags);
+#endif
        return flags;
 }
 EXPORT_SYMBOL(_spin_lock_irqsave);
@@ -84,6 +101,7 @@ void __lockfunc _spin_lock_irq(spinlock_t *lock)
 {
        local_irq_disable();
        preempt_disable();
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_spin_lock(lock);
 }
 EXPORT_SYMBOL(_spin_lock_irq);
@@ -92,6 +110,7 @@ void __lockfunc _spin_lock_bh(spinlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_spin_lock(lock);
 }
 EXPORT_SYMBOL(_spin_lock_bh);
@@ -102,6 +121,7 @@ unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
 
        local_irq_save(flags);
        preempt_disable();
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_read_lock(lock);
        return flags;
 }
@@ -111,6 +131,7 @@ void __lockfunc _read_lock_irq(rwlock_t *lock)
 {
        local_irq_disable();
        preempt_disable();
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_read_lock(lock);
 }
 EXPORT_SYMBOL(_read_lock_irq);
@@ -119,6 +140,7 @@ void __lockfunc _read_lock_bh(rwlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
+       rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_read_lock(lock);
 }
 EXPORT_SYMBOL(_read_lock_bh);
@@ -129,6 +151,7 @@ unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
 
        local_irq_save(flags);
        preempt_disable();
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_write_lock(lock);
        return flags;
 }
@@ -138,6 +161,7 @@ void __lockfunc _write_lock_irq(rwlock_t *lock)
 {
        local_irq_disable();
        preempt_disable();
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_write_lock(lock);
 }
 EXPORT_SYMBOL(_write_lock_irq);
@@ -146,6 +170,7 @@ void __lockfunc _write_lock_bh(rwlock_t *lock)
 {
        local_bh_disable();
        preempt_disable();
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_write_lock(lock);
 }
 EXPORT_SYMBOL(_write_lock_bh);
@@ -153,6 +178,7 @@ EXPORT_SYMBOL(_write_lock_bh);
 void __lockfunc _spin_lock(spinlock_t *lock)
 {
        preempt_disable();
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_spin_lock(lock);
 }
 
@@ -161,6 +187,7 @@ EXPORT_SYMBOL(_spin_lock);
 void __lockfunc _write_lock(rwlock_t *lock)
 {
        preempt_disable();
+       rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
        _raw_write_lock(lock);
 }
 
@@ -188,7 +215,7 @@ void __lockfunc _##op##_lock(locktype##_t *lock)                    \
                if (!(lock)->break_lock)                                \
                        (lock)->break_lock = 1;                         \
                while (!op##_can_lock(lock) && (lock)->break_lock)      \
-                       cpu_relax();                                    \
+                       _raw_##op##_relax(&lock->raw_lock);             \
        }                                                               \
        (lock)->break_lock = 0;                                         \
 }                                                                      \
@@ -210,7 +237,7 @@ unsigned long __lockfunc _##op##_lock_irqsave(locktype##_t *lock)   \
                if (!(lock)->break_lock)                                \
                        (lock)->break_lock = 1;                         \
                while (!op##_can_lock(lock) && (lock)->break_lock)      \
-                       cpu_relax();                                    \
+                       _raw_##op##_relax(&lock->raw_lock);             \
        }                                                               \
        (lock)->break_lock = 0;                                         \
        return flags;                                                   \
@@ -256,8 +283,22 @@ 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_);
+       _raw_spin_lock(lock);
+}
+
+EXPORT_SYMBOL(_spin_lock_nested);
+
+#endif
+
 void __lockfunc _spin_unlock(spinlock_t *lock)
 {
+       spin_release(&lock->dep_map, 1, _RET_IP_);
        _raw_spin_unlock(lock);
        preempt_enable();
 }
@@ -265,6 +306,7 @@ 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();
 }
@@ -272,6 +314,7 @@ 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();
 }
@@ -279,6 +322,7 @@ 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();
@@ -287,6 +331,7 @@ 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();
@@ -295,14 +340,16 @@ 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_no_resched();
-       local_bh_enable();
+       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();
@@ -311,6 +358,7 @@ 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();
@@ -319,14 +367,16 @@ 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_no_resched();
-       local_bh_enable();
+       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();
@@ -335,6 +385,7 @@ 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();
@@ -343,9 +394,10 @@ 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_no_resched();
-       local_bh_enable();
+       local_bh_enable_ip((unsigned long)__builtin_return_address(0));
 }
 EXPORT_SYMBOL(_write_unlock_bh);
 
@@ -353,11 +405,13 @@ 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_no_resched();
-       local_bh_enable();
+       local_bh_enable_ip((unsigned long)__builtin_return_address(0));
        return 0;
 }
 EXPORT_SYMBOL(_spin_trylock_bh);