uml: signal handling tidying

This patch tidies the signal handling code slightly.

pending is renamed to signals_pending for symmetry with signals_enabled.

remove_sigstack was unused, so can be deleted.

The value of change_sig was never used, so it is now void and the
return value is not calculated any more.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 12 insertions, 21 deletions

diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index 91a35da5fe90..0fb0cc8d4757 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -63,7 +63,7 @@ static void sig_handler_common(int sig, struct sigcontext *sc)
 #define SIGVTALRM_MASK (1 << SIGVTALRM_BIT)
 
 static int signals_enabled;
-static unsigned int pending;
+static unsigned int signals_pending;
 
 void sig_handler(int sig, struct sigcontext *sc)
 {
@@ -71,7 +71,7 @@ void sig_handler(int sig, struct sigcontext *sc)
 
         enabled = signals_enabled;
         if (!enabled && (sig == SIGIO)) {
-                pending |= SIGIO_MASK;
+                signals_pending |= SIGIO_MASK;
                 return;
         }
 
@@ -99,7 +99,7 @@ void alarm_handler(int sig, struct sigcontext *sc)
 
         enabled = signals_enabled;
         if (!signals_enabled) {
-                pending |= SIGVTALRM_MASK;
+                signals_pending |= SIGVTALRM_MASK;
                 return;
         }
 
@@ -125,16 +125,6 @@ void set_sigstack(void *sig_stack, int size)
                 panic("enabling signal stack failed, errno = %d\n", errno);
 }
 
-void remove_sigstack(void)
-{
-        stack_t stack = ((stack_t) { .ss_flags  = SS_DISABLE,
-                                     .ss_sp     = NULL,
-                                     .ss_size   = 0 });
-
-        if (sigaltstack(&stack, NULL) != 0)
-                panic("disabling signal stack failed, errno = %d\n", errno);
-}
-
 void (*handlers[_NSIG])(int sig, struct sigcontext *sc);
 
 void handle_signal(int sig, struct sigcontext *sc)
@@ -213,13 +203,14 @@ void set_handler(int sig, void (*handler)(int), int flags, ...)
 
 int change_sig(int signal, int on)
 {
-        sigset_t sigset, old;
+        sigset_t sigset;
 
         sigemptyset(&sigset);
         sigaddset(&sigset, signal);
-        if (sigprocmask(on ? SIG_UNBLOCK : SIG_BLOCK, &sigset, &old) < 0)
+        if (sigprocmask(on ? SIG_UNBLOCK : SIG_BLOCK, &sigset, NULL) < 0)
                 return -errno;
-        return !sigismember(&old, signal);
+
+        return 0;
 }
 
 void block_signals(void)
@@ -244,26 +235,26 @@ void unblock_signals(void)
         /*
          * We loop because the IRQ handler returns with interrupts off.  So,
          * interrupts may have arrived and we need to re-enable them and
-         * recheck pending.
+         * recheck signals_pending.
          */
         while(1) {
                 /*
                  * Save and reset save_pending after enabling signals.  This
-                 * way, pending won't be changed while we're reading it.
+                 * way, signals_pending won't be changed while we're reading it.
                  */
                 signals_enabled = 1;
 
                 /*
-                 * Setting signals_enabled and reading pending must
+                 * Setting signals_enabled and reading signals_pending must
                  * happen in this order.
                  */
                 barrier();
 
-                save_pending = pending;
+                save_pending = signals_pending;
                 if (save_pending == 0)
                         return;
 
-                pending = 0;
+                signals_pending = 0;
 
                 /*
                  * We have pending interrupts, so disable signals, as the