get_signal_to_deliver: use the cached ->signal/sighand values

Cache the values of current->signal/sighand.  Shrinks .text a bit and makes
the code more readable.  Also, remove "sigset_t *mask", it is pointless
because in fact we save the constant offset.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/signal.c b/kernel/signal.c
index b266fa46402aea734f0dce3e7b40cbc57e8ca51e..f92e6298930cf991be09c2d6a72c749def0481c2 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1753,8 +1753,9 @@ static int ptrace_signal(int signr, siginfo_t *info,
 int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
                          struct pt_regs *regs, void *cookie)
 {
-       sigset_t *mask = &current->blocked;
-       int signr = 0;
+       struct sighand_struct *sighand = current->sighand;
+       struct signal_struct *signal = current->signal;
+       int signr;
 
 relock:
        /*
@@ -1765,13 +1766,13 @@ relock:
         */
        try_to_freeze();
 
-       spin_lock_irq(&current->sighand->siglock);
+       spin_lock_irq(&sighand->siglock);
 
-       if (unlikely(current->signal->flags & SIGNAL_CLD_MASK)) {
-               int why = (current->signal->flags & SIGNAL_STOP_CONTINUED)
+       if (unlikely(signal->flags & SIGNAL_CLD_MASK)) {
+               int why = (signal->flags & SIGNAL_STOP_CONTINUED)
                                ? CLD_CONTINUED : CLD_STOPPED;
-               current->signal->flags &= ~SIGNAL_CLD_MASK;
-               spin_unlock_irq(&current->sighand->siglock);
+               signal->flags &= ~SIGNAL_CLD_MASK;
+               spin_unlock_irq(&sighand->siglock);
 
                read_lock(&tasklist_lock);
                do_notify_parent_cldstop(current->group_leader, why);
@@ -1782,12 +1783,11 @@ relock:
        for (;;) {
                struct k_sigaction *ka;
 
-               if (unlikely(current->signal->group_stop_count > 0) &&
+               if (unlikely(signal->group_stop_count > 0) &&
                    do_signal_stop(0))
                        goto relock;
 
-               signr = dequeue_signal(current, mask, info);
-
+               signr = dequeue_signal(current, &current->blocked, info);
                if (!signr)
                        break; /* will return 0 */
 
@@ -1797,7 +1797,7 @@ relock:
                                continue;
                }
 
-               ka = &current->sighand->action[signr-1];
+               ka = &sighand->action[signr-1];
                if (ka->sa.sa_handler == SIG_IGN) /* Do nothing.  */
                        continue;
                if (ka->sa.sa_handler != SIG_DFL) {
@@ -1834,14 +1834,14 @@ relock:
                         * We need to check for that and bail out if necessary.
                         */
                        if (signr != SIGSTOP) {
-                               spin_unlock_irq(&current->sighand->siglock);
+                               spin_unlock_irq(&sighand->siglock);
 
                                /* signals can be posted during this window */
 
                                if (is_current_pgrp_orphaned())
                                        goto relock;
 
-                               spin_lock_irq(&current->sighand->siglock);
+                               spin_lock_irq(&sighand->siglock);
                        }
 
                        if (likely(do_signal_stop(signr))) {
@@ -1856,7 +1856,7 @@ relock:
                        continue;
                }
 
-               spin_unlock_irq(&current->sighand->siglock);
+               spin_unlock_irq(&sighand->siglock);
 
                /*
                 * Anything else is fatal, maybe with a core dump.
@@ -1882,7 +1882,7 @@ relock:
                do_group_exit(signr);
                /* NOTREACHED */
        }
-       spin_unlock_irq(&current->sighand->siglock);
+       spin_unlock_irq(&sighand->siglock);
        return signr;
 }