ANDROID: vendor_hooks: add hook in __mutex_unlock_slowpath()

This hook is used to modify the variables in mutex oemdata when the task releases mutex lock.
This code cannot be done in existing hook trace_android_vh_mutex_unlock_slowpath(), because it is executed after wake_up_q, and there is a risk that the mutex object has been freed.

Bug: 362700382

Change-Id: I7787c0ea51959642a010891606b2bc39fe056dd2
Signed-off-by: zhujingpeng <[email protected]>

Author: zhujingpeng

drivers/android/vendor_hooks.c

@@ -293,6 +293,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_rvh_panic_unhandled);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_gzvm_vcpu_exit_reason);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_alter_mutex_list_add);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mutex_unlock_slowpath);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mutex_unlock_slowpath_before_wakeq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_save_track_hash);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_should_fault_around);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_mem_cgroup_id_remove);

include/trace/hooks/dtask.h

@@ -97,6 +97,9 @@ DECLARE_HOOK(android_vh_alter_mutex_list_add,
 DECLARE_HOOK(android_vh_mutex_unlock_slowpath,
 	TP_PROTO(struct mutex *lock),
 	TP_ARGS(lock));
+DECLARE_HOOK(android_vh_mutex_unlock_slowpath_before_wakeq,
+	TP_PROTO(struct mutex *lock),
+	TP_ARGS(lock));
 
 DECLARE_HOOK(android_vh_exit_signal_whether_wake,
 	TP_PROTO(struct task_struct *p, bool *wake),

kernel/locking/mutex.c

@@ -974,6 +974,7 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
 	if (owner & MUTEX_FLAG_HANDOFF)
 		__mutex_handoff(lock, next);
 
+	trace_android_vh_mutex_unlock_slowpath_before_wakeq(lock);
 	raw_spin_unlock(&lock->wait_lock);
 
 	wake_up_q(&wake_q);