[PATCH 10/11] UML - Eliminate SIGALRM usage

Jeff Dike
2007-09-12T21:21:54Z

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>
--
arch/um/os-Linux/irq.c | 2 +-
arch/um/os-Linux/main.c | 2 +-
arch/um/os-Linux/process.c | 10 +++++-----
arch/um/os-Linux/signal.c | 28 +++++++---------------------
arch/um/os-Linux/skas/process.c | 4 +---
arch/um/os-Linux/skas/trap.c | 5 ++---
arch/um/os-Linux/trap.c | 1 -
7 files changed, 17 insertions(+), 35 deletions(-)

Index: linux-2.6.22/arch/um/os-Linux/skas/process.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/skas/process.c 2007-09-12 15:39:37.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/skas/process.c 2007-09-12 15:47:42.000000000 -0400
@@ -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;
@@ -522,8 +521,7 @@ int start_idle_thread(void *stack, jmp_b
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
Index: linux-2.6.22/arch/um/os-Linux/irq.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/irq.c 2007-09-12 14:50:58.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/irq.c 2007-09-12 15:47:42.000000000 -0400
@@ -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);
}
Index: linux-2.6.22/arch/um/os-Linux/main.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/main.c 2007-09-11 14:09:28.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/main.c 2007-09-12 15:47:42.000000000 -0400
@@ -161,7 +161,7 @@ int __init main(int argc, char **argv, c
* 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 */
Index: linux-2.6.22/arch/um/os-Linux/process.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/process.c 2007-09-12 14:50:58.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/process.c 2007-09-12 15:47:42.000000000 -0400
@@ -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);
Index: linux-2.6.22/arch/um/os-Linux/signal.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/signal.c 2007-09-12 15:41:04.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/signal.c 2007-09-12 15:48:20.000000000 -0400
@@ -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 sigcont
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,
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 sigco

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);
}
}

Index: linux-2.6.22/arch/um/os-Linux/skas/trap.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/skas/trap.c 2007-09-11 14:09:28.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/skas/trap.c 2007-09-12 15:47:42.000000000 -0400
@@ -58,9 +58,8 @@ void sig_handler_common_skas(int sig, vo

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);
Index: linux-2.6.22/arch/um/os-Linux/trap.c
===================================================================
--- linux-2.6.22.orig/arch/um/os-Linux/trap.c 2007-09-11 14:09:28.000000000 -0400
+++ linux-2.6.22/arch/um/os-Linux/trap.c 2007-09-12 15:47:42.000000000 -0400
@@ -20,5 +20,4 @@ void os_fill_handlinfo(struct kern_handl
sig_info[SIGSEGV] = h.page_fault;
sig_info[SIGIO] = h.sigio_handler;
sig_info[SIGVTALRM] = h.timer_handler;
- sig_info[SIGALRM] = h.timer_handler;
}