pid: Implement PIDTYPE_TGID
Everywhere except in the pid array we distinguish between a tasks pid and
a tasks tgid (thread group id). Even in the enumeration we want that
distinction sometimes so we have added __PIDTYPE_TGID. With leader_pid
we almost have an implementation of PIDTYPE_TGID in struct signal_struct.
Add PIDTYPE_TGID as a first class member of the pid_type enumeration and
into the pids array. Then remove the __PIDTYPE_TGID special case and the
leader_pid in signal_struct.
The net size increase is just an extra pointer added to struct pid and
an extra pair of pointers of an hlist_node added to task_struct.
The effect on code maintenance is the removal of a number of special
cases today and the potential to remove many more special cases as
PIDTYPE_TGID gets used to it's fullest. The long term potential
is allowing zombie thread group leaders to exit, which will remove
a lot more special cases in the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 5a6251ac..40e6fae 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -895,7 +895,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
trace_itimer_expire(signo == SIGPROF ?
ITIMER_PROF : ITIMER_VIRTUAL,
- tsk->signal->leader_pid, cur_time);
+ task_tgid(tsk), cur_time);
__group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
}
