[PATCH] sys_setpgid: eliminate unnecessary do_each_task_pid(PIDTYPE_PGID)

All tasks in the process group have the same sid, we don't need to iterate
them all to check that the caller of sys_setpgid() doesn't change its
session.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Oleg Nesterov 2006-12-08 02:38:02 -08:00 committed by Linus Torvalds
parent 84d737866e
commit f020bc468f

View file

@ -1397,16 +1397,13 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
goto out;
if (pgid != pid) {
struct task_struct *p;
struct task_struct *g =
find_task_by_pid_type(PIDTYPE_PGID, pgid);
do_each_task_pid(pgid, PIDTYPE_PGID, p) {
if (process_session(p) == process_session(group_leader))
goto ok_pgid;
} while_each_task_pid(pgid, PIDTYPE_PGID, p);
goto out;
if (!g || process_session(g) != process_session(group_leader))
goto out;
}
ok_pgid:
err = security_task_setpgid(p, pgid);
if (err)
goto out;