[RFC PATCH 1/7] locking/spinlock: Remove the unused spin_lock_bh_nested API

From: Waiman Long
Date: Tue Jan 03 2017 - 13:01:24 EST


The spin_lock_bh_nested() API is defined but is not used anywhere
in the kernel. So all spin_lock_bh_nested() and related APIs are
now removed.

Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
---
include/linux/spinlock.h | 8 --------
include/linux/spinlock_api_smp.h | 2 --
include/linux/spinlock_api_up.h | 1 -
kernel/locking/spinlock.c | 8 --------
4 files changed, 19 deletions(-)

diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 47dd0ce..59248dc 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -180,8 +180,6 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define raw_spin_lock_nested(lock, subclass) \
_raw_spin_lock_nested(lock, subclass)
-# define raw_spin_lock_bh_nested(lock, subclass) \
- _raw_spin_lock_bh_nested(lock, subclass)

# define raw_spin_lock_nest_lock(lock, nest_lock) \
do { \
@@ -197,7 +195,6 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
# define raw_spin_lock_nested(lock, subclass) \
_raw_spin_lock(((void)(subclass), (lock)))
# define raw_spin_lock_nest_lock(lock, nest_lock) _raw_spin_lock(lock)
-# define raw_spin_lock_bh_nested(lock, subclass) _raw_spin_lock_bh(lock)
#endif

#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
@@ -317,11 +314,6 @@ static __always_inline int spin_trylock(spinlock_t *lock)
raw_spin_lock_nested(spinlock_check(lock), subclass); \
} while (0)

-#define spin_lock_bh_nested(lock, subclass) \
-do { \
- raw_spin_lock_bh_nested(spinlock_check(lock), subclass);\
-} while (0)
-
#define spin_lock_nest_lock(lock, nest_lock) \
do { \
raw_spin_lock_nest_lock(spinlock_check(lock), nest_lock); \
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
index 5344268..42dfab8 100644
--- a/include/linux/spinlock_api_smp.h
+++ b/include/linux/spinlock_api_smp.h
@@ -22,8 +22,6 @@
void __lockfunc _raw_spin_lock(raw_spinlock_t *lock) __acquires(lock);
void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
__acquires(lock);
-void __lockfunc _raw_spin_lock_bh_nested(raw_spinlock_t *lock, int subclass)
- __acquires(lock);
void __lockfunc
_raw_spin_lock_nest_lock(raw_spinlock_t *lock, struct lockdep_map *map)
__acquires(lock);
diff --git a/include/linux/spinlock_api_up.h b/include/linux/spinlock_api_up.h
index d3afef9..d0d1888 100644
--- a/include/linux/spinlock_api_up.h
+++ b/include/linux/spinlock_api_up.h
@@ -57,7 +57,6 @@

#define _raw_spin_lock(lock) __LOCK(lock)
#define _raw_spin_lock_nested(lock, subclass) __LOCK(lock)
-#define _raw_spin_lock_bh_nested(lock, subclass) __LOCK(lock)
#define _raw_read_lock(lock) __LOCK(lock)
#define _raw_write_lock(lock) __LOCK(lock)
#define _raw_spin_lock_bh(lock) __LOCK_BH(lock)
diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c
index db3ccb1..4b082b5 100644
--- a/kernel/locking/spinlock.c
+++ b/kernel/locking/spinlock.c
@@ -363,14 +363,6 @@ void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
}
EXPORT_SYMBOL(_raw_spin_lock_nested);

-void __lockfunc _raw_spin_lock_bh_nested(raw_spinlock_t *lock, int subclass)
-{
- __local_bh_disable_ip(_RET_IP_, SOFTIRQ_LOCK_OFFSET);
- spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
- LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock_bh_nested);
-
unsigned long __lockfunc _raw_spin_lock_irqsave_nested(raw_spinlock_t *lock,
int subclass)
{
--
1.8.3.1