-void run_deferred_handler(struct interrupt_data *data, void *v_context);
+static void run_deferred_handler(struct interrupt_data *data, void *v_context);
static void store_signal_data_for_later (struct interrupt_data *data,
void *handler, int signal,
siginfo_t *info,
os_context_t *context);
boolean interrupt_maybe_gc_int(int signal, siginfo_t *info, void *v_context);
-void sigaddset_deferrable(sigset_t *s)
+void
+sigaddset_deferrable(sigset_t *s)
{
sigaddset(s, SIGHUP);
sigaddset(s, SIGINT);
#endif
}
-void sigaddset_blockable(sigset_t *s)
+void
+sigaddset_blockable(sigset_t *s)
{
sigaddset_deferrable(s);
#ifdef LISP_FEATURE_SB_THREAD
int i;
sigemptyset(&empty);
thread_sigmask(SIG_BLOCK, &empty, ¤t);
- for(i=0;i<NSIG;i++) {
+ for(i = 1; i < NSIG; i++) {
if (sigismember(&blockable_sigset, i) && !sigismember(¤t, i))
lose("blockable signal %d not blocked",i);
}
}
-inline static void check_interrupts_enabled_or_lose(os_context_t *context)
+inline static void
+check_interrupts_enabled_or_lose(os_context_t *context)
{
struct thread *thread=arch_os_get_current_thread();
if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL)
* mask ought to be clear anyway most of the time, but may be non-zero
* if we were interrupted e.g. while waiting for a queue. */
-void reset_signal_mask(void)
+void
+reset_signal_mask(void)
{
sigset_t new;
sigemptyset(&new);
thread_sigmask(SIG_SETMASK,&new,0);
}
-void block_blockable_signals(void)
+void
+block_blockable_signals(void)
{
- sigset_t block;
- sigcopyset(&block, &blockable_sigset);
- thread_sigmask(SIG_BLOCK, &block, 0);
+ thread_sigmask(SIG_BLOCK, &blockable_sigset, 0);
}
\f
#endif
}
+/* Stores the context for gc to scavange and builds fake stack
+ * frames. */
void
fake_foreign_function_call(os_context_t *context)
{
/* blocks all blockable signals. If you are calling from a signal handler,
* the usual signal mask will be restored from the context when the handler
* finishes. Otherwise, be careful */
-
void
undo_fake_foreign_function_call(os_context_t *context)
{
thread=arch_os_get_current_thread();
data=thread->interrupt_data;
+#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
+ /* If pseudo_atomic_interrupted is set then the interrupt is going
+ * to be handled now, ergo it's safe to clear it. */
+ arch_clear_pseudo_atomic_interrupted(context);
+#endif
+
if (SymbolValue(GC_INHIBIT,thread)==NIL) {
#ifdef LISP_FEATURE_SB_THREAD
if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL) {
* all our allocation from C now goes through a PA wrapper,
* but still, doesn't hurt.
*
- * Yeah, but non-gencgc platforms that don't really wrap
- * allocation in PA. MG - 2005-08-29 */
+ * Yeah, but non-gencgc platforms don't really wrap allocation
+ * in PA. MG - 2005-08-29 */
lispobj info_sap,context_sap = alloc_sap(context);
info_sap = alloc_sap(info);
#ifdef LISP_FEATURE_SB_THREAD
{
sigset_t unblock;
+ sigemptyset(&unblock);
sigaddset(&unblock, SIG_STOP_FOR_GC);
thread_sigmask(SIG_UNBLOCK, &unblock, 0);
}
* far as C or the kernel is concerned we dealt with the signal
* already; we're just doing the Lisp-level processing now that we
* put off then */
-
-void
+static void
run_deferred_handler(struct interrupt_data *data, void *v_context) {
/* The pending_handler may enable interrupts and then another
* interrupt may hit, overwrite interrupt_data, so reset the
sigfillset(&ss); /* Block everything. */
thread_sigmask(SIG_BLOCK,&ss,0);
- /* The GC can't tell if a thread is a zombie, so this would be a
- * good time to let the kernel reap any of our children in that
- * awful state, to stop them from being waited for indefinitely.
- * Userland reaping is done later when GC is finished */
if(thread->state!=STATE_RUNNING) {
lose("sig_stop_for_gc_handler: wrong thread state: %ld\n",
fixnum_value(thread->state));
FSHOW_SIGNAL((stderr,"thread=%lu suspended\n",thread->os_thread));
sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC);
- sigwaitinfo(&ss,0);
+ /* It is possible to get SIGCONT (and probably other
+ * non-blockable signals) here. */
+ while (sigwaitinfo(&ss,0) != SIG_STOP_FOR_GC);
FSHOW_SIGNAL((stderr,"thread=%lu resumed\n",thread->os_thread));
if(thread->state!=STATE_RUNNING) {
lose("sig_stop_for_gc_handler: wrong thread state on wakeup: %ld\n",
*/
#if (defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
-int *context_eflags_addr(os_context_t *context);
+extern int *context_eflags_addr(os_context_t *context);
#endif
extern lispobj call_into_lisp(lispobj fun, lispobj *args, int nargs);
extern void post_signal_tramp(void);
-void arrange_return_to_lisp_function(os_context_t *context, lispobj function)
+void
+arrange_return_to_lisp_function(os_context_t *context, lispobj function)
{
#if !(defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
void * fun=native_pointer(function);
/* FIXME: this function can go away when all lisp handlers are invoked
* via arrange_return_to_lisp_function. */
-void interrupt_thread_handler(int num, siginfo_t *info, void *v_context)
+void
+interrupt_thread_handler(int num, siginfo_t *info, void *v_context)
{
os_context_t *context = (os_context_t*)arch_os_get_context(&v_context);
/* let the handler enable interrupts again when it sees fit */
* that has the added benefit of automatically discriminating between
* functions and variables.
*/
-void undefined_alien_function() {
+void
+undefined_alien_function() {
funcall0(SymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR));
}
-boolean handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr)
+boolean
+handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr)
{
struct thread *th=arch_os_get_current_thread();
#ifdef LISP_FEATURE_SB_THREAD
else {
sigset_t new;
+ sigemptyset(&new);
sigaddset(&new,SIG_STOP_FOR_GC);
thread_sigmask(SIG_UNBLOCK,&new,0);
}
* noise to install handlers
*/
+/* In Linux 2.4 synchronous signals (sigtrap & co) can be delivered if
+ * they are blocked, in Linux 2.6 the default handler is invoked
+ * instead that usually coredumps. One might hastily think that adding
+ * SA_NODEFER helps, but until ~2.6.13 if SA_NODEFER is specified then
+ * the whole sa_mask is ignored and instead of not adding the signal
+ * in question to the mask. That means if it's not blockable the
+ * signal must be unblocked at the beginning of signal handlers.
+ */
+static volatile int sigaction_nodefer_works = -1;
+
+static void
+sigaction_nodefer_test_handler(int signal, siginfo_t *info, void *void_context)
+{
+ sigset_t empty, current;
+ int i;
+ sigemptyset(&empty);
+ sigprocmask(SIG_BLOCK, &empty, ¤t);
+ for(i = 1; i < NSIG; i++)
+ if (sigismember(¤t, i) != ((i == SIGABRT) ? 1 : 0)) {
+ FSHOW_SIGNAL((stderr, "SA_NODEFER doesn't work, signal %d\n", i));
+ sigaction_nodefer_works = 0;
+ }
+ if (sigaction_nodefer_works == -1)
+ sigaction_nodefer_works = 1;
+}
+
+static void
+see_if_sigaction_nodefer_works()
+{
+ struct sigaction sa, old_sa;
+
+ sa.sa_flags = SA_SIGINFO | SA_NODEFER;
+ sa.sa_sigaction = sigaction_nodefer_test_handler;
+ sigemptyset(&sa.sa_mask);
+ sigaddset(&sa.sa_mask, SIGABRT);
+ sigaction(SIGUSR1, &sa, &old_sa);
+ /* Make sure no signals are blocked. */
+ {
+ sigset_t empty;
+ sigemptyset(&empty);
+ sigprocmask(SIG_SETMASK, &empty, 0);
+ }
+ kill(getpid(), SIGUSR1);
+ while (sigaction_nodefer_works == -1);
+ sigaction(SIGUSR1, &old_sa, NULL);
+}
+
+static void
+unblock_me_trampoline(int signal, siginfo_t *info, void *void_context)
+{
+ sigset_t unblock;
+ sigemptyset(&unblock);
+ sigaddset(&unblock, signal);
+ thread_sigmask(SIG_UNBLOCK, &unblock, 0);
+ interrupt_handle_now_handler(signal, info, void_context);
+}
+
+static void
+low_level_unblock_me_trampoline(int signal, siginfo_t *info, void *void_context)
+{
+ sigset_t unblock;
+ sigemptyset(&unblock);
+ sigaddset(&unblock, signal);
+ thread_sigmask(SIG_UNBLOCK, &unblock, 0);
+ (*interrupt_low_level_handlers[signal])(signal, info, void_context);
+}
+
void
undoably_install_low_level_interrupt_handler (int signal,
void handler(int,
lose("bad signal number %d", signal);
}
- if (sigismember(&deferrable_sigset,signal))
+ if (ARE_SAME_HANDLER(handler, SIG_DFL))
+ sa.sa_sigaction = handler;
+ else if (sigismember(&deferrable_sigset,signal))
sa.sa_sigaction = low_level_maybe_now_maybe_later;
+ else if (!sigaction_nodefer_works &&
+ !sigismember(&blockable_sigset, signal))
+ sa.sa_sigaction = low_level_unblock_me_trampoline;
else
sa.sa_sigaction = handler;
sigcopyset(&sa.sa_mask, &blockable_sigset);
- sa.sa_flags = SA_SIGINFO | SA_RESTART;
+ sa.sa_flags = SA_SIGINFO | SA_RESTART |
+ (sigaction_nodefer_works ? SA_NODEFER : 0);
#ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
if((signal==SIG_MEMORY_FAULT)
#ifdef SIG_INTERRUPT_THREAD
(unsigned int)interrupt_low_level_handlers[signal]));
if (interrupt_low_level_handlers[signal]==0) {
if (ARE_SAME_HANDLER(handler, SIG_DFL) ||
- ARE_SAME_HANDLER(handler, SIG_IGN)) {
+ ARE_SAME_HANDLER(handler, SIG_IGN))
sa.sa_sigaction = handler;
- } else if (sigismember(&deferrable_sigset, signal)) {
+ else if (sigismember(&deferrable_sigset, signal))
sa.sa_sigaction = maybe_now_maybe_later;
- } else {
+ else if (!sigaction_nodefer_works &&
+ !sigismember(&blockable_sigset, signal))
+ sa.sa_sigaction = unblock_me_trampoline;
+ else
sa.sa_sigaction = interrupt_handle_now_handler;
- }
sigcopyset(&sa.sa_mask, &blockable_sigset);
- sa.sa_flags = SA_SIGINFO | SA_RESTART;
+ sa.sa_flags = SA_SIGINFO | SA_RESTART |
+ (sigaction_nodefer_works ? SA_NODEFER : 0);
sigaction(signal, &sa, NULL);
}
{
int i;
SHOW("entering interrupt_init()");
+ see_if_sigaction_nodefer_works();
sigemptyset(&deferrable_sigset);
sigemptyset(&blockable_sigset);
sigaddset_deferrable(&deferrable_sigset);