timers: Rename del_timer_sync() to timer_delete_sync()

[ Upstream commit 9b13df3fb6 ]

The timer related functions do not have a strict timer_ prefixed namespace
which is really annoying.

Rename del_timer_sync() to timer_delete_sync() and provide del_timer_sync()
as a wrapper. Document that del_timer_sync() is not for new code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Link: https://lore.kernel.org/r/20221123201624.954785441@linutronix.de
Stable-dep-of: 0f7352557a35 ("wifi: brcmfmac: Fix use-after-free bug in brcmf_cfg80211_detach")
Signed-off-by: Sasha Levin <sashal@kernel.org>

include/linux/timer.h

@@ -183,7 +183,20 @@ extern int timer_reduce(struct timer_list *timer, unsigned long expires);
 extern void add_timer(struct timer_list *timer);
 
 extern int try_to_del_timer_sync(struct timer_list *timer);
-extern int del_timer_sync(struct timer_list *timer);
+extern int timer_delete_sync(struct timer_list *timer);
+
+/**
+ * del_timer_sync - Delete a pending timer and wait for a running callback
+ * @timer:	The timer to be deleted
+ *
+ * See timer_delete_sync() for detailed explanation.
+ *
+ * Do not use in new code. Use timer_delete_sync() instead.
+ */
+static inline int del_timer_sync(struct timer_list *timer)
+{
+	return timer_delete_sync(timer);
+}
 
 #define del_singleshot_timer_sync(t) del_timer_sync(t)
 

kernel/time/timer.c

@@ -1030,7 +1030,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, unsigned int option
 		/*
 		 * We are trying to schedule the timer on the new base.
 		 * However we can't change timer's base while it is running,
-		 * otherwise del_timer_sync() can't detect that the timer's
+		 * otherwise timer_delete_sync() can't detect that the timer's
 		 * handler yet has not finished. This also guarantees that the
 		 * timer is serialized wrt itself.
 		 */
@@ -1206,7 +1206,7 @@ EXPORT_SYMBOL_GPL(add_timer_on);
  * @timer:	The timer to be deactivated
  *
  * The function only deactivates a pending timer, but contrary to
- * del_timer_sync() it does not take into account whether the timer's
+ * timer_delete_sync() it does not take into account whether the timer's
  * callback function is concurrently executed on a different CPU or not.
  * It neither prevents rearming of the timer. If @timer can be rearmed
  * concurrently then the return value of this function is meaningless.
@@ -1342,7 +1342,7 @@ static inline void del_timer_wait_running(struct timer_list *timer) { }
 #endif
 
 /**
- * del_timer_sync - Deactivate a timer and wait for the handler to finish.
+ * timer_delete_sync - Deactivate a timer and wait for the handler to finish.
  * @timer:	The timer to be deactivated
  *
  * Synchronization rules: Callers must prevent restarting of the timer,
@@ -1364,10 +1364,10 @@ static inline void del_timer_wait_running(struct timer_list *timer) { }
  *    spin_lock_irq(somelock);
  *                                     <IRQ>
  *                                        spin_lock(somelock);
- *    del_timer_sync(mytimer);
+ *    timer_delete_sync(mytimer);
  *    while (base->running_timer == mytimer);
  *
- * Now del_timer_sync() will never return and never release somelock.
+ * Now timer_delete_sync() will never return and never release somelock.
  * The interrupt on the other CPU is waiting to grab somelock but it has
  * interrupted the softirq that CPU0 is waiting to finish.
  *
@@ -1380,7 +1380,7 @@ static inline void del_timer_wait_running(struct timer_list *timer) { }
  * * %0	- The timer was not pending
  * * %1	- The timer was pending and deactivated
  */
-int del_timer_sync(struct timer_list *timer)
+int timer_delete_sync(struct timer_list *timer)
 {
 	int ret;
 
@@ -1420,7 +1420,7 @@ int del_timer_sync(struct timer_list *timer)
 
 	return ret;
 }
-EXPORT_SYMBOL(del_timer_sync);
+EXPORT_SYMBOL(timer_delete_sync);
 
 static void call_timer_fn(struct timer_list *timer,
 			  void (*fn)(struct timer_list *),
@@ -1442,8 +1442,8 @@ static void call_timer_fn(struct timer_list *timer,
 #endif
 	/*
 	 * Couple the lock chain with the lock chain at
-	 * del_timer_sync() by acquiring the lock_map around the fn()
+	 * timer_delete_sync() by acquiring the lock_map around the fn()
-	 * call here and in del_timer_sync().
+	 * call here and in timer_delete_sync().
 	 */
 	lock_map_acquire(&lockdep_map);