[merged mm-nonmm-stable] change-thread_group_empty-to-use-task_struct-thread_node.patch removed from -mm tree

[merged mm-nonmm-stable] change-thread_group_empty-to-use-task_struct-thread_node.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: change thread_group_empty() to use task_struct->thread_node
has been removed from the -mm tree.  Its filename was
     change-thread_group_empty-to-use-task_struct-thread_node.patch

This patch was dropped because it was merged into the mm-nonmm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Oleg Nesterov <oleg@redhat.com>
Subject: change thread_group_empty() to use task_struct->thread_node
Date: Sat, 26 Aug 2023 13:14:06 +0200

Patch series "kill task_struct->thread_group".


This patch (of 2):

It could use list_is_singular() but this way it is cheaper.  Plus the
thread_group_leader() check makes it clear that thread_group_empty() can
only return true if p is a group leader.  This was not immediately obvious
before this patch.

task_struct->thread_group no longer has users, it can die.

Link: https://lkml.kernel.org/r/20230826111200.GA22982@redhat.com
Link: https://lkml.kernel.org/r/20230826111406.GA23238@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/signal.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/include/linux/sched/signal.h~change-thread_group_empty-to-use-task_struct-thread_node
+++ a/include/linux/sched/signal.h
@@ -733,7 +733,8 @@ static inline struct task_struct *next_t
 
 static inline int thread_group_empty(struct task_struct *p)
 {
-	return list_empty(&p->thread_group);
+	return thread_group_leader(p) &&
+	       list_is_last(&p->thread_node, &p->signal->thread_head);
 }
 
 #define delay_group_leader(p) \
_

Patches currently in -mm which might be from oleg@redhat.com are