[PATCH 17/17] bit_spinlock: Track bit spin locks with lockdep

From: Matthew Wilcox (Oracle)
Date: Thu Apr 08 2021 - 23:03:19 EST


Now that all users have been converted, require the split_lock parameter
be passed to bit_spin_lock(), bit_spin_unlock() and variants. Use it
to track the lockdep state of each lock.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/bit_spinlock.h | 26 ++++++++++----------------
1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/include/linux/bit_spinlock.h b/include/linux/bit_spinlock.h
index 6c5bbb55b334..a02ce695198a 100644
--- a/include/linux/bit_spinlock.h
+++ b/include/linux/bit_spinlock.h
@@ -34,30 +34,21 @@ static inline void bit_spin_lock_nested(int bitnum, unsigned long *addr,
preempt_disable();
}
#endif
+ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
__acquire(bitlock);
}

static inline void bit_spin_lock(int bitnum, unsigned long *addr,
- ...)
+ struct split_lock *lock)
{
- preempt_disable();
-#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
- while (unlikely(test_and_set_bit_lock(bitnum, addr))) {
- preempt_enable();
- do {
- cpu_relax();
- } while (test_bit(bitnum, addr));
- preempt_disable();
- }
-#endif
- __acquire(bitlock);
+ bit_spin_lock_nested(bitnum, addr, lock, 0);
}

/*
* Return true if it was acquired
*/
static inline int bit_spin_trylock(int bitnum, unsigned long *addr,
- ...)
+ struct split_lock *lock)
{
preempt_disable();
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
@@ -66,6 +57,7 @@ static inline int bit_spin_trylock(int bitnum, unsigned long *addr,
return 0;
}
#endif
+ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
__acquire(bitlock);
return 1;
}
@@ -74,11 +66,12 @@ static inline int bit_spin_trylock(int bitnum, unsigned long *addr,
* bit-based spin_unlock()
*/
static inline void bit_spin_unlock(int bitnum, unsigned long *addr,
- ...)
+ struct split_lock *lock)
{
#ifdef CONFIG_DEBUG_SPINLOCK
BUG_ON(!test_bit(bitnum, addr));
#endif
+ spin_release(&lock->dep_map, _RET_IP_);
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
clear_bit_unlock(bitnum, addr);
#endif
@@ -92,11 +85,12 @@ static inline void bit_spin_unlock(int bitnum, unsigned long *addr,
* protecting the rest of the flags in the word.
*/
static inline void __bit_spin_unlock(int bitnum, unsigned long *addr,
- ...)
+ struct split_lock *lock)
{
#ifdef CONFIG_DEBUG_SPINLOCK
BUG_ON(!test_bit(bitnum, addr));
#endif
+ spin_release(&lock->dep_map, _RET_IP_);
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
__clear_bit_unlock(bitnum, addr);
#endif
@@ -113,6 +107,7 @@ static inline void __bit_spin_unlock(int bitnum, unsigned long *addr,
static inline void bit_spin_unlock_assign(unsigned long *addr,
unsigned long val, struct split_lock *lock)
{
+ spin_release(&lock->dep_map, _RET_IP_);
smp_store_release(addr, val);
preempt_enable();
__release(bitlock);
@@ -133,4 +128,3 @@ static inline int bit_spin_is_locked(int bitnum, unsigned long *addr)
}

#endif /* __LINUX_BIT_SPINLOCK_H */
-
--
2.30.2