From 8e1f385104ac044f1552686ad6e1cbc71cc05a30 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@redhat.com>
Date: Sat, 26 Aug 2023 13:14:09 +0200
Subject: [PATCH] kill task_struct->thread_group

The last user was removed by the previous patch.

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>
Cc: Peter Zijlstra <peterz@infradead.org>
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(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 77f01ac385f7a..6d1341b1673f5 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1002,7 +1002,6 @@ 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;
diff --git a/init/init_task.c b/init/init_task.c
index ff6c4b9bfe6b1..c0de0200fd562 100644
--- a/init/init_task.c
+++ b/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,
diff --git a/kernel/exit.c b/kernel/exit.c
index edb50b4c99728..f3ba4b97a7d97 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -133,7 +133,6 @@ static void __unhash_process(struct task_struct *p, bool group_dead)
 		list_del_init(&p->sibling);
 		__this_cpu_dec(process_counts);
 	}
-	list_del_rcu(&p->thread_group);
 	list_del_rcu(&p->thread_node);
 }
 
diff --git a/kernel/fork.c b/kernel/fork.c
index 3b6d20dfb9a85..b9d3aa493bbd2 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2576,7 +2576,6 @@ __latent_entropy struct task_struct *copy_process(
 	p->dirty_paused_when = 0;
 
 	p->pdeath_signal = 0;
-	INIT_LIST_HEAD(&p->thread_group);
 	p->task_works = NULL;
 	clear_posix_cputimers_work(p);
 
@@ -2704,8 +2703,6 @@ __latent_entropy struct task_struct *copy_process(
 			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);
 		}
-- 
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