signals: split do_tkill

Split out the code from do_tkill to make it reusable by the follow up
patch which implements sys_rt_tgsigqueueinfo

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>

1 files changed, 18 insertions, 12 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index d8034737db4c..56d27acad87e 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2278,24 +2278,17 @@ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig)
         return kill_something_info(sig, &info, pid);
 }
 
-static int do_tkill(pid_t tgid, pid_t pid, int sig)
+static int
+do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
 {
-        int error;
-        struct siginfo info;
         struct task_struct *p;
         unsigned long flags;
-
-        error = -ESRCH;
-        info.si_signo = sig;
-        info.si_errno = 0;
-        info.si_code = SI_TKILL;
-        info.si_pid = task_tgid_vnr(current);
-        info.si_uid = current_uid();
+        int error = -ESRCH;
 
         rcu_read_lock();
         p = find_task_by_vpid(pid);
         if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) {
-                error = check_kill_permission(sig, &info, p);
+                error = check_kill_permission(sig, info, p);
                 /*
                  * The null signal is a permissions and process existence
                  * probe.  No signal is actually delivered.
@@ -2305,7 +2298,7 @@ static int do_tkill(pid_t tgid, pid_t pid, int sig)
                  * signal is private anyway.
                  */
                 if (!error && sig && lock_task_sighand(p, &flags)) {
-                        error = specific_send_sig_info(sig, &info, p);
+                        error = specific_send_sig_info(sig, info, p);
                         unlock_task_sighand(p, &flags);
                 }
         }
@@ -2314,6 +2307,19 @@ static int do_tkill(pid_t tgid, pid_t pid, int sig)
         return error;
 }
 
+static int do_tkill(pid_t tgid, pid_t pid, int sig)
+{
+        struct siginfo info;
+
+        info.si_signo = sig;
+        info.si_errno = 0;
+        info.si_code = SI_TKILL;
+        info.si_pid = task_tgid_vnr(current);
+        info.si_uid = current_uid();
+
+        return do_send_specific(tgid, pid, sig, &info);
+}
+
 /**
  *  sys_tgkill - send signal to one specific thread
  *  @tgid: the thread group ID of the thread