uml: eliminate SIGALRM

Now that ITIMER_REAL is no longer used, there is no need for any use of
SIGALRM whatsoever.  This patch removes all mention of it.

In addition, real_alarm_handler took a signal argument which is now always
SIGVTALRM.  So, that is gone.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

7 files changed, 17 insertions, 35 deletions

diff --git a/arch/um/os-Linux/irq.c b/arch/um/os-Linux/irq.c
index 2fe482219b6b..6aa6f95d6524 100644
--- a/arch/um/os-Linux/irq.c
+++ b/arch/um/os-Linux/irq.c
@@ -146,6 +146,6 @@ void init_irq_signals(int on_sigstack)
         flags = on_sigstack ? SA_ONSTACK : 0;
 
         set_handler(SIGIO, (__sighandler_t) sig_handler, flags | SA_RESTART,
-                    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+                    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
         signal(SIGWINCH, SIG_IGN);
 }
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
index 1518f7a45a24..82c3778627b8 100644
--- a/arch/um/os-Linux/main.c
+++ b/arch/um/os-Linux/main.c
@@ -161,7 +161,7 @@ int __init main(int argc, char **argv, char **envp)
          * some time) and cause a segfault.
          */
 
-        /* stop timers and set SIG*ALRM to be ignored */
+        /* stop timers and set SIGVTALRM to be ignored */
         disable_timer();
 
         /* disable SIGIO for the fds and set SIGIO to be ignored */
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index 90b480cf78f4..37781db4ceca 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -238,15 +238,15 @@ out:
 void init_new_thread_signals(void)
 {
         set_handler(SIGSEGV, (__sighandler_t) sig_handler, SA_ONSTACK,
-                    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+                    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
         set_handler(SIGTRAP, (__sighandler_t) sig_handler, SA_ONSTACK,
-                    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+                    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
         set_handler(SIGFPE, (__sighandler_t) sig_handler, SA_ONSTACK,
-                    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+                    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
         set_handler(SIGILL, (__sighandler_t) sig_handler, SA_ONSTACK,
-                    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+                    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
         set_handler(SIGBUS, (__sighandler_t) sig_handler, SA_ONSTACK,
-                    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+                    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
         signal(SIGHUP, SIG_IGN);
 
         init_irq_signals(1);
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index fbad174775ee..e9800b0b5689 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -15,8 +15,7 @@
 #include "user.h"
 
 /*
- * These are the asynchronous signals.  SIGVTALRM and SIGARLM are handled
- * together under SIGVTALRM_BIT.  SIGPROF is excluded because we want to
+ * These are the asynchronous signals.  SIGPROF is excluded because we want to
  * be able to profile all of UML, not just the non-critical sections.  If
  * profiling is not thread-safe, then that is not my problem.  We can disable
  * profiling when SMP is enabled in that case.
@@ -27,9 +26,6 @@
 #define SIGVTALRM_BIT 1
 #define SIGVTALRM_MASK (1 << SIGVTALRM_BIT)
 
-#define SIGALRM_BIT 2
-#define SIGALRM_MASK (1 << SIGALRM_BIT)
-
 /*
  * These are used by both the signal handlers and
  * block/unblock_signals.  I don't want modifications cached in a
@@ -55,7 +51,7 @@ void sig_handler(int sig, struct sigcontext *sc)
         set_signals(enabled);
 }
 
-static void real_alarm_handler(int sig, struct sigcontext *sc)
+static void real_alarm_handler(struct sigcontext *sc)
 {
         struct uml_pt_regs regs;
 
@@ -63,7 +59,7 @@ static void real_alarm_handler(int sig, struct sigcontext *sc)
                 copy_sc(&regs, sc);
         regs.is_user = 0;
         unblock_signals();
-        timer_handler(sig, &regs);
+        timer_handler(SIGVTALRM, &regs);
 }
 
 void alarm_handler(int sig, struct sigcontext *sc)
@@ -72,27 +68,20 @@ void alarm_handler(int sig, struct sigcontext *sc)
 
         enabled = signals_enabled;
         if (!signals_enabled) {
-                if (sig == SIGVTALRM)
-                        pending |= SIGVTALRM_MASK;
-                else pending |= SIGALRM_MASK;
-
+                pending |= SIGVTALRM_MASK;
                 return;
         }
 
         block_signals();
 
-        real_alarm_handler(sig, sc);
+        real_alarm_handler(sc);
         set_signals(enabled);
 }
 
 void timer_init(void)
 {
         set_handler(SIGVTALRM, (__sighandler_t) alarm_handler,
-                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH,
-                    SIGALRM, -1);
-        set_handler(SIGALRM, (__sighandler_t) alarm_handler,
-                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH,
-                    SIGALRM, -1);
+                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, -1);
 }
 
 void set_sigstack(void *sig_stack, int size)
@@ -267,11 +256,8 @@ void unblock_signals(void)
                 if (save_pending & SIGIO_MASK)
                         sig_handler_common_skas(SIGIO, NULL);
 
-                if (save_pending & SIGALRM_MASK)
-                        real_alarm_handler(SIGALRM, NULL);
-
                 if (save_pending & SIGVTALRM_MASK)
-                        real_alarm_handler(SIGVTALRM, NULL);
+                        real_alarm_handler(NULL);
         }
 }
 
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 3e64814e888e..9936531a2620 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -222,7 +222,6 @@ static int userspace_tramp(void *stack)
                 sigemptyset(&sa.sa_mask);
                 sigaddset(&sa.sa_mask, SIGIO);
                 sigaddset(&sa.sa_mask, SIGWINCH);
-                sigaddset(&sa.sa_mask, SIGALRM);
                 sigaddset(&sa.sa_mask, SIGVTALRM);
                 sigaddset(&sa.sa_mask, SIGUSR1);
                 sa.sa_flags = SA_ONSTACK;
@@ -539,8 +538,7 @@ int start_idle_thread(void *stack, jmp_buf *switch_buf)
         int n;
 
         set_handler(SIGWINCH, (__sighandler_t) sig_handler,
-                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGALRM,
-                    SIGVTALRM, -1);
+                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGVTALRM, -1);
 
         /*
          * Can't use UML_SETJMP or UML_LONGJMP here because they save
diff --git a/arch/um/os-Linux/skas/trap.c b/arch/um/os-Linux/skas/trap.c
index e53face44200..3b1b9244f468 100644
--- a/arch/um/os-Linux/skas/trap.c
+++ b/arch/um/os-Linux/skas/trap.c
@@ -58,9 +58,8 @@ void sig_handler_common_skas(int sig, void *sc_ptr)
 
         handler = sig_info[sig];
 
-        /* unblock SIGALRM, SIGVTALRM, SIGIO if sig isn't IRQ signal */
-        if (sig != SIGIO && sig != SIGWINCH &&
-            sig != SIGVTALRM && sig != SIGALRM)
+        /* unblock SIGVTALRM, SIGIO if sig isn't IRQ signal */
+        if ((sig != SIGIO) && (sig != SIGWINCH) && (sig != SIGVTALRM))
                 unblock_signals();
 
         handler(sig, r);
diff --git a/arch/um/os-Linux/trap.c b/arch/um/os-Linux/trap.c
index d3a34ca8a891..2a1c9843e32e 100644
--- a/arch/um/os-Linux/trap.c
+++ b/arch/um/os-Linux/trap.c
@@ -20,5 +20,4 @@ void os_fill_handlinfo(struct kern_handlers h)
         sig_info[SIGSEGV] = h.page_fault;
         sig_info[SIGIO] = h.sigio_handler;
         sig_info[SIGVTALRM] = h.timer_handler;
-        sig_info[SIGALRM] = h.timer_handler;
 }