release_task: kill the no longer needed get/put_pid(thread_pid)

After the commit 7903f907a2 ("pid: perform free_pid() calls outside
of tasklist_lock") __unhash_process() -> detach_pid() no longer calls
free_pid(), proc_flush_pid() can just use p->thread_pid without the
now pointless get_pid() + put_pid().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/20250411121857.GA10550@redhat.com
Reviewed-by: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Oleg Nesterov
2025-04-11 14:18:57 +02:00
committed by Christian Brauner
parent a9d7de0f68
commit 0a36bad017

View File

@@ -258,7 +258,8 @@ void release_task(struct task_struct *p)
pidfs_exit(p);
cgroup_release(p);
thread_pid = get_pid(p->thread_pid);
/* Retrieve @thread_pid before __unhash_process() may set it to NULL. */
thread_pid = task_pid(p);
write_lock_irq(&tasklist_lock);
ptrace_release_task(p);
@@ -287,8 +288,8 @@ void release_task(struct task_struct *p)
}
write_unlock_irq(&tasklist_lock);
/* @thread_pid can't go away until free_pids() below */
proc_flush_pid(thread_pid);
put_pid(thread_pid);
add_device_randomness(&p->se.sum_exec_runtime,
sizeof(p->se.sum_exec_runtime));
free_pids(post.pids);