Re: [PATCHv3 4/6] tty/lockdep: Add ldisc_sem asserts

From: Peter Zijlstra
Date: Tue Sep 11 2018 - 07:59:54 EST


Subject: tty/ldsem: Convert to regular lockdep annotations

For some reason ldsem has its own lockdep wrappers, make them go away.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
drivers/tty/tty_ldsem.c | 51 ++++++++++++++-----------------------------------
1 file changed, 14 insertions(+), 37 deletions(-)

diff --git a/drivers/tty/tty_ldsem.c b/drivers/tty/tty_ldsem.c
index 0c98d88f795a..60beada5be6c 100644
--- a/drivers/tty/tty_ldsem.c
+++ b/drivers/tty/tty_ldsem.c
@@ -34,29 +34,6 @@
#include <linux/sched/task.h>


-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __acq(l, s, t, r, c, n, i) \
- lock_acquire(&(l)->dep_map, s, t, r, c, n, i)
-# define __rel(l, n, i) \
- lock_release(&(l)->dep_map, n, i)
-#define lockdep_acquire(l, s, t, i) __acq(l, s, t, 0, 1, NULL, i)
-#define lockdep_acquire_nest(l, s, t, n, i) __acq(l, s, t, 0, 1, n, i)
-#define lockdep_acquire_read(l, s, t, i) __acq(l, s, t, 1, 1, NULL, i)
-#define lockdep_release(l, n, i) __rel(l, n, i)
-#else
-# define lockdep_acquire(l, s, t, i) do { } while (0)
-# define lockdep_acquire_nest(l, s, t, n, i) do { } while (0)
-# define lockdep_acquire_read(l, s, t, i) do { } while (0)
-# define lockdep_release(l, n, i) do { } while (0)
-#endif
-
-#ifdef CONFIG_LOCK_STAT
-# define lock_stat(_lock, stat) lock_##stat(&(_lock)->dep_map, _RET_IP_)
-#else
-# define lock_stat(_lock, stat) do { } while (0)
-#endif
-
-
#if BITS_PER_LONG == 64
# define LDSEM_ACTIVE_MASK 0xffffffffL
#else
@@ -310,17 +287,17 @@ static int __ldsem_down_read_nested(struct ld_semaphore *sem,
{
long count;

- lockdep_acquire_read(sem, subclass, 0, _RET_IP_);
+ rwsem_acquire_read(&sem->dep_map, subclass, 0, _RET_IP_);

count = atomic_long_add_return(LDSEM_READ_BIAS, &sem->count);
if (count <= 0) {
- lock_stat(sem, contended);
+ lock_contended(&sem->dep_map, _RET_IP_);
if (!down_read_failed(sem, count, timeout)) {
- lockdep_release(sem, 1, _RET_IP_);
+ rwsem_release(&sem->dep_map, 1, _RET_IP_);
return 0;
}
}
- lock_stat(sem, acquired);
+ lock_acquired(&sem->dep_map, _RET_IP_);
return 1;
}

@@ -329,17 +306,17 @@ static int __ldsem_down_write_nested(struct ld_semaphore *sem,
{
long count;

- lockdep_acquire(sem, subclass, 0, _RET_IP_);
+ rwsem_acquire(&sem->dep_map, subclass, 0, _RET_IP_);

count = atomic_long_add_return(LDSEM_WRITE_BIAS, &sem->count);
if ((count & LDSEM_ACTIVE_MASK) != LDSEM_ACTIVE_BIAS) {
- lock_stat(sem, contended);
+ lock_contended(&sem->dep_map, _RET_IP_);
if (!down_write_failed(sem, count, timeout)) {
- lockdep_release(sem, 1, _RET_IP_);
+ rwsem_release(&sem->dep_map, 1, _RET_IP_);
return 0;
}
}
- lock_stat(sem, acquired);
+ lock_acquired(&sem->dep_map, _RET_IP_);
return 1;
}

@@ -362,8 +339,8 @@ int ldsem_down_read_trylock(struct ld_semaphore *sem)

while (count >= 0) {
if (atomic_long_try_cmpxchg(&sem->count, &count, count + LDSEM_READ_BIAS)) {
- lockdep_acquire_read(sem, 0, 1, _RET_IP_);
- lock_stat(sem, acquired);
+ rwsem_acquire_read(&sem->dep_map, 0, 1, _RET_IP_);
+ lock_acquired(&sem->dep_map, _RET_IP_);
return 1;
}
}
@@ -388,8 +365,8 @@ int ldsem_down_write_trylock(struct ld_semaphore *sem)

while ((count & LDSEM_ACTIVE_MASK) == 0) {
if (atomic_long_try_cmpxchg(&sem->count, &count, count + LDSEM_WRITE_BIAS)) {
- lockdep_acquire(sem, 0, 1, _RET_IP_);
- lock_stat(sem, acquired);
+ rwsem_acquire(&sem->dep_map, 0, 1, _RET_IP_);
+ lock_acquired(&sem->dep_map, _RET_IP_);
return 1;
}
}
@@ -403,7 +380,7 @@ void ldsem_up_read(struct ld_semaphore *sem)
{
long count;

- lockdep_release(sem, 1, _RET_IP_);
+ rwsem_release(&sem->dep_map, 1, _RET_IP_);

count = atomic_long_add_return(-LDSEM_READ_BIAS, &sem->count);
if (count < 0 && (count & LDSEM_ACTIVE_MASK) == 0)
@@ -417,7 +394,7 @@ void ldsem_up_write(struct ld_semaphore *sem)
{
long count;

- lockdep_release(sem, 1, _RET_IP_);
+ rwsem_release(&sem->dep_map, 1, _RET_IP_);

count = atomic_long_add_return(-LDSEM_WRITE_BIAS, &sem->count);
if (count < 0)