diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2023-08-24 16:32:01 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-04 10:41:56 -0700 |
| commit | d639cf4abb4d171ab2456904da5668c42b5c1937 (patch) | |
| tree | 4f4d1c2c495b08807ddbe2ee0dc583e3346234fe /include/linux/sched/signal.h | |
| parent | 33a9813825710fdc2b980d566ee391fd093a36c6 (diff) | |
change next_thread() to use __next_thread() ?: group_leader
This relies on fact that group leader is always the 1st entry in the
signal->thread_head list.
With or without this change, if the lockless next_thread(last_thread)
races with exec it can return the old or the new leader.
We are almost ready to kill task->thread_group, after this change its
only user is thread_group_empty().
Link: https://lkml.kernel.org/r/20230824143201.GB31222@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>
Diffstat (limited to 'include/linux/sched/signal.h')
| -rw-r--r-- | include/linux/sched/signal.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 7fb34b8cda54..cffc882d367f 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -726,10 +726,9 @@ static inline struct task_struct *__next_thread(struct task_struct *p) thread_node); } -static inline struct task_struct *next_thread(const struct task_struct *p) +static inline struct task_struct *next_thread(struct task_struct *p) { - return list_entry_rcu(p->thread_group.next, - struct task_struct, thread_group); + return __next_thread(p) ?: p->group_leader; } static inline int thread_group_empty(struct task_struct *p) |