Re: + kill-task_struct-thread_group.patch added to mm-nonmm-unstable branch

[Oleg Nesterov <oleg@redhat.com>]

Hi Andrew,

> From: Oleg Nesterov <oleg@redhat.com>
> Subject: kill task_struct->thread_group
> Date: Sat, 26 Aug 2023 13:14:09 +0200
>
> The last user was removed by the previous patch.

No, no ;)

this series depends on 2 previous patches, see

	https://lore.kernel.org/all/20230824143112.GA31208@redhat.com/

sorry for confusion,

Oleg.


> Link: https://lkml.kernel.org/r/20230826111409.GA23243@redhat.com
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
> Cc: Eric W. Biederman <ebiederm@xmission.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
> 
>  include/linux/sched.h |    1 -
>  init/init_task.c      |    1 -
>  kernel/exit.c         |    1 -
>  kernel/fork.c         |    3 ---
>  4 files changed, 6 deletions(-)
> 
> --- a/include/linux/sched.h~kill-task_struct-thread_group
> +++ a/include/linux/sched.h
> @@ -997,7 +997,6 @@ struct task_struct {
>  	/* PID/PID hash table linkage. */
>  	struct pid			*thread_pid;
>  	struct hlist_node		pid_links[PIDTYPE_MAX];
> -	struct list_head		thread_group;
>  	struct list_head		thread_node;
>  
>  	struct completion		*vfork_done;
> --- a/init/init_task.c~kill-task_struct-thread_group
> +++ a/init/init_task.c
> @@ -132,7 +132,6 @@ struct task_struct init_task
>  	.pi_lock	= __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
>  	.timer_slack_ns = 50000, /* 50 usec default slack */
>  	.thread_pid	= &init_struct_pid,
> -	.thread_group	= LIST_HEAD_INIT(init_task.thread_group),
>  	.thread_node	= LIST_HEAD_INIT(init_signals.thread_head),
>  #ifdef CONFIG_AUDIT
>  	.loginuid	= INVALID_UID,
> --- a/kernel/exit.c~kill-task_struct-thread_group
> +++ a/kernel/exit.c
> @@ -133,7 +133,6 @@ static void __unhash_process(struct task
>  		list_del_init(&p->sibling);
>  		__this_cpu_dec(process_counts);
>  	}
> -	list_del_rcu(&p->thread_group);
>  	list_del_rcu(&p->thread_node);
>  }
>  
> --- a/kernel/fork.c~kill-task_struct-thread_group
> +++ a/kernel/fork.c
> @@ -2575,7 +2575,6 @@ __latent_entropy struct task_struct *cop
>  	p->dirty_paused_when = 0;
>  
>  	p->pdeath_signal = 0;
> -	INIT_LIST_HEAD(&p->thread_group);
>  	p->task_works = NULL;
>  	clear_posix_cputimers_work(p);
>  
> @@ -2703,8 +2702,6 @@ __latent_entropy struct task_struct *cop
>  			atomic_inc(&current->signal->live);
>  			refcount_inc(&current->signal->sigcnt);
>  			task_join_group_stop(p);
> -			list_add_tail_rcu(&p->thread_group,
> -					  &p->group_leader->thread_group);
>  			list_add_tail_rcu(&p->thread_node,
>  					  &p->signal->thread_head);
>  		}
> _
> 
> Patches currently in -mm which might be from oleg@redhat.com are
> 
> change-thread_group_empty-to-use-task_struct-thread_node.patch
> kill-task_struct-thread_group.patch
>