locking/ww_mutex: Gather mutex_waiter initialization

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211304.281927514@linutronix.de

diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index 7ef5a36..bc8abb8 100644 (file)
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -30,6 +30,7 @@ void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
        memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
        waiter->magic = waiter;
        INIT_LIST_HEAD(&waiter->list);
+       waiter->ww_ctx = MUTEX_POISON_WW_CTX;
 }
 
 void debug_mutex_wake_waiter(struct mutex *lock, struct mutex_waiter *waiter)

diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 73ad862..6cb27c5 100644 (file)
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -982,17 +982,15 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
        }
 
        debug_mutex_lock_common(lock, &waiter);
+       waiter.task = current;
+       if (ww_ctx)
+               waiter.ww_ctx = ww_ctx;
 
        lock_contended(&lock->dep_map, ip);
 
        if (!use_ww_ctx) {
                /* add waiting tasks to the end of the waitqueue (FIFO): */
                __mutex_add_waiter(lock, &waiter, &lock->wait_list);
-
-
-#ifdef CONFIG_DEBUG_MUTEXES
-               waiter.ww_ctx = MUTEX_POISON_WW_CTX;
-#endif
        } else {
                /*
                 * Add in stamp order, waking up waiters that must kill
@@ -1001,12 +999,8 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
                ret = __ww_mutex_add_waiter(&waiter, lock, ww_ctx);
                if (ret)
                        goto err_early_kill;
-
-               waiter.ww_ctx = ww_ctx;
        }
 
-       waiter.task = current;
-
        set_current_state(state);
        for (;;) {
                bool first;