[patch 02/14] locking/rtmutex: Remove rtmutex deadlock tester leftovers

Thomas Gleixner
2021-03-23T21:40:56Z

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

The following debug members of struct rtmutex are unused:

- save_state: No users

- file,line: Printed if ::name is NULL. This is only used for non-futex
locks so ::name is never NULL

- magic: Assigned to NULL by rt_mutex_destroy(), no further usage

Remove them along with unused inlines and macros leftovers related to
the long gone deadlock tester.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/rtmutex.h | 7 ++-----
kernel/locking/rtmutex-debug.c | 7 +------
kernel/locking/rtmutex-debug.h | 2 --
kernel/locking/rtmutex.c | 3 ---
kernel/locking/rtmutex.h | 2 --
kernel/locking/rtmutex_common.h | 1 -
6 files changed, 3 insertions(+), 19 deletions(-)

--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -32,10 +32,7 @@ struct rt_mutex {
struct rb_root_cached waiters;
struct task_struct *owner;
#ifdef CONFIG_DEBUG_RT_MUTEXES
- int save_state;
- const char *name, *file;
- int line;
- void *magic;
+ const char *name;
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
@@ -60,7 +57,7 @@ struct hrtimer_sleeper;

#ifdef CONFIG_DEBUG_RT_MUTEXES
# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
- , .name = #mutexname, .file = __FILE__, .line = __LINE__
+ , .name = #mutexname

# define rt_mutex_init(mutex) \
do { \
--- a/kernel/locking/rtmutex-debug.c
+++ b/kernel/locking/rtmutex-debug.c
@@ -42,12 +42,7 @@ static void printk_task(struct task_stru

static void printk_lock(struct rt_mutex *lock, int print_owner)
{
- if (lock->name)
- printk(" [%p] {%s}\n",
- lock, lock->name);
- else
- printk(" [%p] {%s:%d}\n",
- lock, lock->file, lock->line);
+ printk(" [%p] {%s}\n", lock, lock->name);

if (print_owner && rt_mutex_owner(lock)) {
printk(".. ->owner: %p\n", lock->owner);
--- a/kernel/locking/rtmutex-debug.h
+++ b/kernel/locking/rtmutex-debug.h
@@ -22,8 +22,6 @@ extern void debug_rt_mutex_deadlock(enum
struct rt_mutex_waiter *waiter,
struct rt_mutex *lock);
extern void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter);
-# define debug_rt_mutex_reset_waiter(w) \
- do { (w)->deadlock_lock = NULL; } while (0)

static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *waiter,
enum rtmutex_chainwalk walk)
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1594,9 +1594,6 @@ void __sched rt_mutex_futex_unlock(struc
void rt_mutex_destroy(struct rt_mutex *lock)
{
WARN_ON(rt_mutex_is_locked(lock));
-#ifdef CONFIG_DEBUG_RT_MUTEXES
- lock->magic = NULL;
-#endif
}
EXPORT_SYMBOL_GPL(rt_mutex_destroy);

--- a/kernel/locking/rtmutex.h
+++ b/kernel/locking/rtmutex.h
@@ -11,7 +11,6 @@
* Non-debug version.
*/

-#define rt_mutex_deadlock_check(l) (0)
#define debug_rt_mutex_init_waiter(w) do { } while (0)
#define debug_rt_mutex_free_waiter(w) do { } while (0)
#define debug_rt_mutex_lock(l) do { } while (0)
@@ -21,7 +20,6 @@
#define debug_rt_mutex_init(m, n, k) do { } while (0)
#define debug_rt_mutex_deadlock(d, a ,l) do { } while (0)
#define debug_rt_mutex_print_deadlock(w) do { } while (0)
-#define debug_rt_mutex_reset_waiter(w) do { } while (0)

static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
{
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -30,7 +30,6 @@ struct rt_mutex_waiter {
struct task_struct *task;
struct rt_mutex *lock;
#ifdef CONFIG_DEBUG_RT_MUTEXES
- unsigned long ip;
struct pid *deadlock_task_pid;
struct rt_mutex *deadlock_lock;
#endif