signals: introduce do_send_sig_info() helper

Introduce do_send_sig_info() and convert group_send_sig_info(),
send_sig_info(), do_send_specific() to use this helper.

Hopefully it will have more users soon, it allows to specify
specific/group behaviour via "bool group" argument.

Shaves 80 bytes from .text.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Oleg Nesterov 2009-09-23 15:57:00 -07:00 committed by Linus Torvalds
parent 964ee7df90
commit 4a30debfb7
2 changed files with 29 additions and 29 deletions

View file

@ -233,6 +233,8 @@ static inline int valid_signal(unsigned long sig)
}
extern int next_signal(struct sigpending *pending, sigset_t *mask);
extern int do_send_sig_info(int sig, struct siginfo *info,
struct task_struct *p, bool group);
extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p);
extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *);
extern long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig,

View file

@ -971,6 +971,20 @@ specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t)
return send_signal(sig, info, t, 0);
}
int do_send_sig_info(int sig, struct siginfo *info, struct task_struct *p,
bool group)
{
unsigned long flags;
int ret = -ESRCH;
if (lock_task_sighand(p, &flags)) {
ret = send_signal(sig, info, p, group);
unlock_task_sighand(p, &flags);
}
return ret;
}
/*
* Force a signal that the process can't ignore: if necessary
* we unblock the signal and change any SIG_IGN to SIG_DFL.
@ -1068,18 +1082,10 @@ struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long
*/
int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
{
unsigned long flags;
int ret;
int ret = check_kill_permission(sig, info, p);
ret = check_kill_permission(sig, info, p);
if (!ret && sig) {
ret = -ESRCH;
if (lock_task_sighand(p, &flags)) {
ret = __group_send_sig_info(sig, info, p);
unlock_task_sighand(p, &flags);
}
}
if (!ret && sig)
ret = do_send_sig_info(sig, info, p, true);
return ret;
}
@ -1224,15 +1230,9 @@ static int kill_something_info(int sig, struct siginfo *info, pid_t pid)
* These are for backward compatibility with the rest of the kernel source.
*/
/*
* The caller must ensure the task can't exit.
*/
int
send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
{
int ret;
unsigned long flags;
/*
* Make sure legacy kernel users don't send in bad values
* (normal paths check this in check_kill_permission).
@ -1240,10 +1240,7 @@ send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
if (!valid_signal(sig))
return -EINVAL;
spin_lock_irqsave(&p->sighand->siglock, flags);
ret = specific_send_sig_info(sig, info, p);
spin_unlock_irqrestore(&p->sighand->siglock, flags);
return ret;
return do_send_sig_info(sig, info, p, false);
}
#define __si_special(priv) \
@ -2278,7 +2275,6 @@ static int
do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
{
struct task_struct *p;
unsigned long flags;
int error = -ESRCH;
rcu_read_lock();
@ -2288,14 +2284,16 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
/*
* The null signal is a permissions and process existence
* probe. No signal is actually delivered.
*
* If lock_task_sighand() fails we pretend the task dies
* after receiving the signal. The window is tiny, and the
* signal is private anyway.
*/
if (!error && sig && lock_task_sighand(p, &flags)) {
error = specific_send_sig_info(sig, info, p);
unlock_task_sighand(p, &flags);
if (!error && sig) {
error = do_send_sig_info(sig, info, p, false);
/*
* If lock_task_sighand() failed we pretend the task
* dies after receiving the signal. The window is tiny,
* and the signal is private anyway.
*/
if (unlikely(error == -ESRCH))
error = 0;
}
}
rcu_read_unlock();