Commit 2873cd31 authored by Eric W. Biederman's avatar Eric W. Biederman
Browse files

exit: Remove profile_handoff_task 



All profile_handoff_task does is notify the task_free_notifier chain.
The helpers task_handoff_register and task_handoff_unregister are used
to add and delete entries from that chain and are never called.

So remove the dead code and make it much easier to read and reason
about __put_task_struct.

Suggested-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/87fspyw6m0.fsf@email.froward.int.ebiederm.org


Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
parent 2d4bcf88

include/linux/profile.h

+0 −19
Original line number Diff line number Diff line
@@ -61,14 +61,6 @@ static inline void profile_hit(int type, void *ip) 
struct task_struct;

struct mm_struct;



/* task is dead, free task struct ? Returns 1 if

 * the task was taken, 0 if the task should be freed.

 */

int profile_handoff_task(struct task_struct * task);



int task_handoff_register(struct notifier_block * n);

int task_handoff_unregister(struct notifier_block * n);



#else



#define prof_on 0
@@ -93,17 +85,6 @@ static inline void profile_hit(int type, void *ip) 
	return;

}



static inline int task_handoff_register(struct notifier_block * n)

{

	return -ENOSYS;

}



static inline int task_handoff_unregister(struct notifier_block * n)

{

	return -ENOSYS;

}



#define profile_handoff_task(a) (0)



#endif /* CONFIG_PROFILING */

kernel/fork.c

+1 −3
Original line number Diff line number Diff line
@@ -754,8 +754,6 @@ void __put_task_struct(struct task_struct *tsk) 
	delayacct_tsk_free(tsk);

	put_signal_struct(tsk->signal);

	sched_core_free(tsk);



	if (!profile_handoff_task(tsk))

	free_task(tsk);

}

EXPORT_SYMBOL_GPL(__put_task_struct);

kernel/profile.c

+0 −23
Original line number Diff line number Diff line
@@ -133,29 +133,6 @@ int __ref profile_init(void) 
	return -ENOMEM;

}



/* Profile event notifications */



static ATOMIC_NOTIFIER_HEAD(task_free_notifier);



int profile_handoff_task(struct task_struct *task)

{

	int ret;

	ret = atomic_notifier_call_chain(&task_free_notifier, 0, task);

	return (ret == NOTIFY_OK) ? 1 : 0;

}



int task_handoff_register(struct notifier_block *n)

{

	return atomic_notifier_chain_register(&task_free_notifier, n);

}

EXPORT_SYMBOL_GPL(task_handoff_register);



int task_handoff_unregister(struct notifier_block *n)

{

	return atomic_notifier_chain_unregister(&task_free_notifier, n);

}

EXPORT_SYMBOL_GPL(task_handoff_unregister);



#if defined(CONFIG_SMP) && defined(CONFIG_PROC_FS)

/*

 * Each cpu has a pair of open-addressed hashtables for pending