#include "globals.h"
#include "lispregs.h"
#include "validate.h"
+#include "interr.h"
#include "gc.h"
#include "alloc.h"
#include "dynbind.h"
-#include "interr.h"
+#include "pseudo-atomic.h"
#include "genesis/fdefn.h"
#include "genesis/simple-fun.h"
#include "genesis/cons.h"
+/* When we catch an internal error, should we pass it back to Lisp to
+ * be handled in a high-level way? (Early in cold init, the answer is
+ * 'no', because Lisp is still too brain-dead to handle anything.
+ * After sufficient initialization has been completed, the answer
+ * becomes 'yes'.) */
+boolean internal_errors_enabled = 0;
-
-static void run_deferred_handler(struct interrupt_data *data, void *v_context);
#ifndef LISP_FEATURE_WIN32
+static
+void (*interrupt_low_level_handlers[NSIG]) (int, siginfo_t*, os_context_t*);
+#endif
+union interrupt_handler interrupt_handlers[NSIG];
+
+/* Under Linux on some architectures, we appear to have to restore the
+ * FPU control word from the context, as after the signal is delivered
+ * we appear to have a null FPU control word. */
+#if defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
+#define RESTORE_FP_CONTROL_WORD(context,void_context) \
+ os_context_t *context = arch_os_get_context(&void_context); \
+ os_restore_fp_control(context);
+#else
+#define RESTORE_FP_CONTROL_WORD(context,void_context) \
+ os_context_t *context = arch_os_get_context(&void_context);
+#endif
+
+/* Foreign code may want to start some threads on its own.
+ * Non-targetted, truly asynchronous signals can be delivered to
+ * basically any thread, but invoking Lisp handlers in such foregign
+ * threads is really bad, so let's resignal it.
+ *
+ * This should at least bring attention to the problem, but it cannot
+ * work for SIGSEGV and similar. It is good enough for timers, and
+ * maybe all deferrables. */
+
+#if defined(LISP_FEATURE_SB_THREAD) && !defined(LISP_FEATURE_WIN32)
+static void
+add_handled_signals(sigset_t *sigset)
+{
+ int i;
+ for(i = 1; i < NSIG; i++) {
+ if (!(ARE_SAME_HANDLER(interrupt_low_level_handlers[i], SIG_DFL)) ||
+ !(ARE_SAME_HANDLER(interrupt_handlers[i].c, SIG_DFL))) {
+ sigaddset(sigset, i);
+ }
+ }
+}
+
+void block_signals(sigset_t *what, sigset_t *where, sigset_t *old);
+#endif
+
+static boolean
+maybe_resignal_to_lisp_thread(int signal, os_context_t *context)
+{
+#if defined(LISP_FEATURE_SB_THREAD) && !defined(LISP_FEATURE_WIN32)
+ if (!pthread_getspecific(lisp_thread)) {
+ if (!(sigismember(&deferrable_sigset,signal))) {
+ corruption_warning_and_maybe_lose
+ ("Received signal %d in non-lisp thread %lu, resignalling to a lisp thread.",
+ signal,
+ pthread_self());
+ }
+ {
+ sigset_t sigset;
+ sigemptyset(&sigset);
+ add_handled_signals(&sigset);
+ block_signals(&sigset, 0, 0);
+ block_signals(&sigset, os_context_sigmask_addr(context), 0);
+ kill(getpid(), signal);
+ }
+ return 1;
+ } else
+#endif
+ return 0;
+}
+
+/* These are to be used in signal handlers. Currently all handlers are
+ * called from one of:
+ *
+ * interrupt_handle_now_handler
+ * maybe_now_maybe_later
+ * unblock_me_trampoline
+ * low_level_handle_now_handler
+ * low_level_maybe_now_maybe_later
+ * low_level_unblock_me_trampoline
+ *
+ * This gives us a single point of control (or six) over errno, fp
+ * control word, and fixing up signal context on sparc.
+ *
+ * The SPARC/Linux platform doesn't quite do signals the way we want
+ * them done. The third argument in the handler isn't filled in by the
+ * kernel properly, so we fix it up ourselves in the
+ * arch_os_get_context(..) function. -- CSR, 2002-07-23
+ */
+#define SAVE_ERRNO(signal,context,void_context) \
+ { \
+ int _saved_errno = errno; \
+ RESTORE_FP_CONTROL_WORD(context,void_context); \
+ if (!maybe_resignal_to_lisp_thread(signal, context)) \
+ {
+
+#define RESTORE_ERRNO \
+ } \
+ errno = _saved_errno; \
+ }
+
+static void run_deferred_handler(struct interrupt_data *data,
+ os_context_t *context);
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
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);
+\f
+
+/* Generic signal related utilities. */
+
+void
+get_current_sigmask(sigset_t *sigset)
+{
+ /* Get the current sigmask, by blocking the empty set. */
+ thread_sigmask(SIG_BLOCK, 0, sigset);
+}
+
+void
+block_signals(sigset_t *what, sigset_t *where, sigset_t *old)
+{
+ if (where) {
+ int i;
+ if (old)
+ sigcopyset(old, where);
+ for(i = 1; i < NSIG; i++) {
+ if (sigismember(what, i))
+ sigaddset(where, i);
+ }
+ } else {
+ thread_sigmask(SIG_BLOCK, what, old);
+ }
+}
+
+void
+unblock_signals(sigset_t *what, sigset_t *where, sigset_t *old)
+{
+ if (where) {
+ int i;
+ if (old)
+ sigcopyset(old, where);
+ for(i = 1; i < NSIG; i++) {
+ if (sigismember(what, i))
+ sigdelset(where, i);
+ }
+ } else {
+ thread_sigmask(SIG_UNBLOCK, what, old);
+ }
+}
+
+static void
+print_sigset(sigset_t *sigset)
+{
+ int i;
+ for(i = 1; i < NSIG; i++) {
+ if (sigismember(sigset, i))
+ fprintf(stderr, "Signal %d masked\n", i);
+ }
+}
+
+/* Return 1 is all signals is sigset2 are masked in sigset, return 0
+ * if all re unmasked else die. Passing NULL for sigset is a shorthand
+ * for the current sigmask. */
+boolean
+all_signals_blocked_p(sigset_t *sigset, sigset_t *sigset2,
+ const char *name)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ int i;
+ boolean has_blocked = 0, has_unblocked = 0;
+ sigset_t current;
+ if (sigset == 0) {
+ get_current_sigmask(¤t);
+ sigset = ¤t;
+ }
+ for(i = 1; i < NSIG; i++) {
+ if (sigismember(sigset2, i)) {
+ if (sigismember(sigset, i))
+ has_blocked = 1;
+ else
+ has_unblocked = 1;
+ }
+ }
+ if (has_blocked && has_unblocked) {
+ print_sigset(sigset);
+ lose("some %s signals blocked, some unblocked\n", name);
+ }
+ if (has_blocked)
+ return 1;
+ else
+ return 0;
+#endif
+}
+\f
+
+/* Deferrables, blockables, gc signals. */
void
sigaddset_deferrable(sigset_t *s)
{
sigaddset(s, SIGHUP);
sigaddset(s, SIGINT);
+ sigaddset(s, SIGTERM);
sigaddset(s, SIGQUIT);
sigaddset(s, SIGPIPE);
sigaddset(s, SIGALRM);
sigaddset(s, SIGTSTP);
sigaddset(s, SIGCHLD);
sigaddset(s, SIGIO);
+#ifndef LISP_FEATURE_HPUX
sigaddset(s, SIGXCPU);
sigaddset(s, SIGXFSZ);
+#endif
sigaddset(s, SIGVTALRM);
sigaddset(s, SIGPROF);
sigaddset(s, SIGWINCH);
+}
-#if !((defined(LISP_FEATURE_DARWIN) || defined(LISP_FEATURE_FREEBSD)) && defined(LISP_FEATURE_SB_THREAD))
- sigaddset(s, SIGUSR1);
- sigaddset(s, SIGUSR2);
+void
+sigaddset_blockable(sigset_t *sigset)
+{
+ sigaddset_deferrable(sigset);
+ sigaddset_gc(sigset);
+}
+
+void
+sigaddset_gc(sigset_t *sigset)
+{
+#ifdef THREADS_USING_GCSIGNAL
+ sigaddset(sigset,SIG_STOP_FOR_GC);
#endif
+}
+
+/* initialized in interrupt_init */
+sigset_t deferrable_sigset;
+sigset_t blockable_sigset;
+sigset_t gc_sigset;
-#ifdef LISP_FEATURE_SB_THREAD
- sigaddset(s, SIG_INTERRUPT_THREAD);
#endif
+
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+boolean
+deferrables_blocked_p(sigset_t *sigset)
+{
+ return all_signals_blocked_p(sigset, &deferrable_sigset, "deferrable");
}
+#endif
void
-sigaddset_blockable(sigset_t *s)
+check_deferrables_unblocked_or_lose(sigset_t *sigset)
{
- sigaddset_deferrable(s);
-#ifdef LISP_FEATURE_SB_THREAD
-#ifdef SIG_RESUME_FROM_GC
- sigaddset(s, SIG_RESUME_FROM_GC);
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ if (deferrables_blocked_p(sigset))
+ lose("deferrables blocked\n");
#endif
- sigaddset(s, SIG_STOP_FOR_GC);
+}
+
+void
+check_deferrables_blocked_or_lose(sigset_t *sigset)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ if (!deferrables_blocked_p(sigset))
+ lose("deferrables unblocked\n");
#endif
}
-/* initialized in interrupt_init */
-static sigset_t deferrable_sigset;
-static sigset_t blockable_sigset;
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+boolean
+blockables_blocked_p(sigset_t *sigset)
+{
+ return all_signals_blocked_p(sigset, &blockable_sigset, "blockable");
+}
+#endif
+
+void
+check_blockables_unblocked_or_lose(sigset_t *sigset)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ if (blockables_blocked_p(sigset))
+ lose("blockables blocked\n");
#endif
+}
void
-check_blockables_blocked_or_lose(void)
+check_blockables_blocked_or_lose(sigset_t *sigset)
{
#if !defined(LISP_FEATURE_WIN32)
- /* Get the current sigmask, by blocking the empty set. */
- sigset_t empty,current;
- int i;
- sigemptyset(&empty);
- thread_sigmask(SIG_BLOCK, &empty, ¤t);
- for(i = 1; i < NSIG; i++) {
- if (sigismember(&blockable_sigset, i) && !sigismember(¤t, i))
- lose("blockable signal %d not blocked\n",i);
- }
+ /* On Windows, there are no actual signals, but since the win32 port
+ * tracks the sigmask and checks it explicitly, some functions are
+ * still required to keep the mask set up properly. (After all, the
+ * goal of the sigmask emulation is to not have to change all the
+ * call sites in the first place.)
+ *
+ * However, this does not hold for all signals equally: While
+ * deferrables matter ("is interrupt-thread okay?"), it is not worth
+ * having to set up blockables properly (which include the
+ * non-existing GC signals).
+ *
+ * Yet, as the original comment explains it:
+ * Adjusting FREE-INTERRUPT-CONTEXT-INDEX* and other aspecs of
+ * fake_foreign_function_call machinery are sometimes useful here[...].
+ *
+ * So we merely skip this assertion.
+ * -- DFL, trying to expand on a comment by AK.
+ */
+ if (!blockables_blocked_p(sigset))
+ lose("blockables unblocked\n");
#endif
}
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+#if !defined(LISP_FEATURE_WIN32)
+boolean
+gc_signals_blocked_p(sigset_t *sigset)
+{
+ return all_signals_blocked_p(sigset, &gc_sigset, "gc");
+}
+#endif
+
void
-check_gc_signals_unblocked_or_lose(void)
+check_gc_signals_unblocked_or_lose(sigset_t *sigset)
{
-#ifdef LISP_FEATURE_SB_THREAD
-# if !defined(LISP_FEATURE_WIN32)
- /* Get the current sigmask, by blocking the empty set. */
- sigset_t empty,current;
- sigemptyset(&empty);
- thread_sigmask(SIG_BLOCK, &empty, ¤t);
- if (sigismember(¤t, SIG_STOP_FOR_GC))
- lose("SIG_STOP_FOR_GC blocked in thread %p at a bad place\n",
- arch_os_get_current_thread());
-# if defined(SIG_RESUME_FROM_GC)
- if (sigismember(¤t, SIG_RESUME_FROM_GC))
- lose("SIG_RESUME_FROM_GC blocked in thread %p at a bad place\n",
- arch_os_get_current_thread());
-# endif
-# endif
+#if !defined(LISP_FEATURE_WIN32)
+ if (gc_signals_blocked_p(sigset))
+ lose("gc signals blocked\n");
#endif
}
void
-unblock_gc_signals(void)
+check_gc_signals_blocked_or_lose(sigset_t *sigset)
{
-#ifdef LISP_FEATURE_SB_THREAD
- sigset_t new;
- sigemptyset(&new);
-#if defined(SIG_RESUME_FROM_GC)
- sigaddset(&new,SIG_RESUME_FROM_GC);
+#if !defined(LISP_FEATURE_WIN32)
+ if (!gc_signals_blocked_p(sigset))
+ lose("gc signals unblocked\n");
#endif
- sigaddset(&new,SIG_STOP_FOR_GC);
- thread_sigmask(SIG_UNBLOCK,&new,0);
+}
+#endif
+
+void
+block_deferrable_signals(sigset_t *where, sigset_t *old)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ block_signals(&deferrable_sigset, where, old);
#endif
}
-inline static void
-check_interrupts_enabled_or_lose(os_context_t *context)
+void
+block_blockable_signals(sigset_t *where, sigset_t *old)
{
- struct thread *thread=arch_os_get_current_thread();
- if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL)
- lose("interrupts not enabled\n");
- if (
-#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
- (!foreign_function_call_active) &&
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ block_signals(&blockable_sigset, where, old);
#endif
- arch_pseudo_atomic_atomic(context))
- lose ("in pseudo atomic section\n");
}
-/* When we catch an internal error, should we pass it back to Lisp to
- * be handled in a high-level way? (Early in cold init, the answer is
- * 'no', because Lisp is still too brain-dead to handle anything.
- * After sufficient initialization has been completed, the answer
- * becomes 'yes'.) */
-boolean internal_errors_enabled = 0;
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+void
+block_gc_signals(sigset_t *where, sigset_t *old)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ block_signals(&gc_sigset, where, old);
+#endif
+}
+#endif
-#ifndef LISP_FEATURE_WIN32
-static void (*interrupt_low_level_handlers[NSIG]) (int, siginfo_t*, void*);
+void
+unblock_deferrable_signals(sigset_t *where, sigset_t *old)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ if (interrupt_handler_pending_p())
+ lose("unblock_deferrable_signals: losing proposition\n");
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+ check_gc_signals_unblocked_or_lose(where);
#endif
-union interrupt_handler interrupt_handlers[NSIG];
+ unblock_signals(&deferrable_sigset, where, old);
+#endif
+}
-/* At the toplevel repl we routinely call this function. The signal
- * 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
+unblock_blockable_signals(sigset_t *where, sigset_t *old)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ unblock_signals(&blockable_sigset, where, old);
+#endif
+}
+#ifndef LISP_FEATURE_SB_SAFEPOINT
void
-reset_signal_mask(void)
+unblock_gc_signals(sigset_t *where, sigset_t *old)
{
#ifndef LISP_FEATURE_WIN32
- sigset_t new;
- sigemptyset(&new);
- thread_sigmask(SIG_SETMASK,&new,0);
+ unblock_signals(&gc_sigset, where, old);
#endif
}
+#endif
void
-block_blockable_signals(void)
+unblock_signals_in_context_and_maybe_warn(os_context_t *context)
{
-#ifndef LISP_FEATURE_WIN32
- thread_sigmask(SIG_BLOCK, &blockable_sigset, 0);
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ sigset_t *sigset = os_context_sigmask_addr(context);
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+ if (all_signals_blocked_p(sigset, &gc_sigset, "gc")) {
+ corruption_warning_and_maybe_lose(
+"Enabling blocked gc signals to allow returning to Lisp without risking\n\
+gc deadlocks. Since GC signals are only blocked in signal handlers when \n\
+they are not safe to interrupt at all, this is a pretty severe occurrence.\n");
+ unblock_gc_signals(sigset, 0);
+ }
#endif
+ if (!interrupt_handler_pending_p()) {
+ unblock_deferrable_signals(sigset, 0);
+ }
+#endif
+}
+\f
+
+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)
+ lose("interrupts not enabled\n");
+ if (arch_pseudo_atomic_atomic(context))
+ lose ("in pseudo atomic section\n");
}
+/* Save sigset (or the current sigmask if 0) if there is no pending
+ * handler, because that means that deferabbles are already blocked.
+ * The purpose is to avoid losing the pending gc signal if a
+ * deferrable interrupt async unwinds between clearing the pseudo
+ * atomic and trapping to GC.*/
+#ifndef LISP_FEATURE_SB_SAFEPOINT
void
-block_deferrable_signals(void)
+maybe_save_gc_mask_and_block_deferrables(sigset_t *sigset)
{
#ifndef LISP_FEATURE_WIN32
- thread_sigmask(SIG_BLOCK, &deferrable_sigset, 0);
+ struct thread *thread = arch_os_get_current_thread();
+ struct interrupt_data *data = thread->interrupt_data;
+ sigset_t oldset;
+ /* Obviously, this function is called when signals may not be
+ * blocked. Let's make sure we are not interrupted. */
+ block_blockable_signals(0, &oldset);
+#ifndef LISP_FEATURE_SB_THREAD
+ /* With threads a SIG_STOP_FOR_GC and a normal GC may also want to
+ * block. */
+ if (data->gc_blocked_deferrables)
+ lose("gc_blocked_deferrables already true\n");
+#endif
+ if ((!data->pending_handler) &&
+ (!data->gc_blocked_deferrables)) {
+ FSHOW_SIGNAL((stderr,"/setting gc_blocked_deferrables\n"));
+ data->gc_blocked_deferrables = 1;
+ if (sigset) {
+ /* This is the sigmask of some context. */
+ sigcopyset(&data->pending_mask, sigset);
+ sigaddset_deferrable(sigset);
+ thread_sigmask(SIG_SETMASK,&oldset,0);
+ return;
+ } else {
+ /* Operating on the current sigmask. Save oldset and
+ * unblock gc signals. In the end, this is equivalent to
+ * blocking the deferrables. */
+ sigcopyset(&data->pending_mask, &oldset);
+ thread_sigmask(SIG_UNBLOCK, &gc_sigset, 0);
+ return;
+ }
+ }
+ thread_sigmask(SIG_SETMASK,&oldset,0);
+#endif
+}
#endif
+
+/* Are we leaving WITH-GCING and already running with interrupts
+ * enabled, without the protection of *GC-INHIBIT* T and there is gc
+ * (or stop for gc) pending, but we haven't trapped yet? */
+int
+in_leaving_without_gcing_race_p(struct thread *thread)
+{
+ return ((SymbolValue(IN_WITHOUT_GCING,thread) != NIL) &&
+ (SymbolValue(INTERRUPTS_ENABLED,thread) != NIL) &&
+ (SymbolValue(GC_INHIBIT,thread) == NIL) &&
+ ((SymbolValue(GC_PENDING,thread) != NIL)
+#if defined(LISP_FEATURE_SB_THREAD)
+ || (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL)
+#endif
+ ));
}
+/* Check our baroque invariants. */
+void
+check_interrupt_context_or_lose(os_context_t *context)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ struct thread *thread = arch_os_get_current_thread();
+ struct interrupt_data *data = thread->interrupt_data;
+ int interrupt_deferred_p = (data->pending_handler != 0);
+ int interrupt_pending = (SymbolValue(INTERRUPT_PENDING,thread) != NIL);
+ sigset_t *sigset = os_context_sigmask_addr(context);
+ /* On PPC pseudo_atomic_interrupted is cleared when coming out of
+ * handle_allocation_trap. */
+#if defined(LISP_FEATURE_GENCGC) && !defined(GENCGC_IS_PRECISE)
+ int interrupts_enabled = (SymbolValue(INTERRUPTS_ENABLED,thread) != NIL);
+ int gc_inhibit = (SymbolValue(GC_INHIBIT,thread) != NIL);
+ int gc_pending = (SymbolValue(GC_PENDING,thread) == T);
+ int pseudo_atomic_interrupted = get_pseudo_atomic_interrupted(thread);
+ int in_race_p = in_leaving_without_gcing_race_p(thread);
+ /* In the time window between leaving the *INTERRUPTS-ENABLED* NIL
+ * section and trapping, a SIG_STOP_FOR_GC would see the next
+ * check fail, for this reason sig_stop_for_gc handler does not
+ * call this function. */
+ if (interrupt_deferred_p) {
+ if (!(!interrupts_enabled || pseudo_atomic_interrupted || in_race_p))
+ lose("Stray deferred interrupt.\n");
+ }
+ if (gc_pending)
+ if (!(pseudo_atomic_interrupted || gc_inhibit || in_race_p))
+ lose("GC_PENDING, but why?\n");
+#if defined(LISP_FEATURE_SB_THREAD)
+ {
+ int stop_for_gc_pending =
+ (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL);
+ if (stop_for_gc_pending)
+ if (!(pseudo_atomic_interrupted || gc_inhibit || in_race_p))
+ lose("STOP_FOR_GC_PENDING, but why?\n");
+ if (pseudo_atomic_interrupted)
+ if (!(gc_pending || stop_for_gc_pending || interrupt_deferred_p))
+ lose("pseudo_atomic_interrupted, but why?\n");
+ }
+#else
+ if (pseudo_atomic_interrupted)
+ if (!(gc_pending || interrupt_deferred_p))
+ lose("pseudo_atomic_interrupted, but why?\n");
+#endif
+#endif
+ if (interrupt_pending && !interrupt_deferred_p)
+ lose("INTERRUPT_PENDING but not pending handler.\n");
+ if ((data->gc_blocked_deferrables) && interrupt_pending)
+ lose("gc_blocked_deferrables and interrupt pending\n.");
+ if (data->gc_blocked_deferrables)
+ check_deferrables_blocked_or_lose(sigset);
+ if (interrupt_pending || interrupt_deferred_p ||
+ data->gc_blocked_deferrables)
+ check_deferrables_blocked_or_lose(sigset);
+ else {
+ check_deferrables_unblocked_or_lose(sigset);
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+ /* If deferrables are unblocked then we are open to signals
+ * that run lisp code. */
+ check_gc_signals_unblocked_or_lose(sigset);
+#endif
+ }
+#endif
+}
\f
/*
* utility routines used by various signal handlers
/* Build a fake stack frame or frames */
- current_control_frame_pointer =
- (lispobj *)(unsigned long)
+ access_control_frame_pointer(th) =
+ (lispobj *)(uword_t)
(*os_context_register_addr(context, reg_CSP));
- if ((lispobj *)(unsigned long)
+ if ((lispobj *)(uword_t)
(*os_context_register_addr(context, reg_CFP))
- == current_control_frame_pointer) {
+ == access_control_frame_pointer(th)) {
/* There is a small window during call where the callee's
* frame isn't built yet. */
if (lowtag_of(*os_context_register_addr(context, reg_CODE))
== FUN_POINTER_LOWTAG) {
/* We have called, but not built the new frame, so
* build it for them. */
- current_control_frame_pointer[0] =
+ access_control_frame_pointer(th)[0] =
*os_context_register_addr(context, reg_OCFP);
- current_control_frame_pointer[1] =
+ access_control_frame_pointer(th)[1] =
*os_context_register_addr(context, reg_LRA);
- current_control_frame_pointer += 8;
+ access_control_frame_pointer(th) += 8;
/* Build our frame on top of it. */
oldcont = (lispobj)(*os_context_register_addr(context, reg_CFP));
}
oldcont = (lispobj)(*os_context_register_addr(context, reg_CFP));
}
- current_control_stack_pointer = current_control_frame_pointer + 8;
+ access_control_stack_pointer(th) = access_control_frame_pointer(th) + 8;
- current_control_frame_pointer[0] = oldcont;
- current_control_frame_pointer[1] = NIL;
- current_control_frame_pointer[2] =
+ access_control_frame_pointer(th)[0] = oldcont;
+ access_control_frame_pointer(th)[1] = NIL;
+ access_control_frame_pointer(th)[2] =
(lispobj)(*os_context_register_addr(context, reg_CODE));
#endif
}
struct thread *thread=arch_os_get_current_thread();
/* context_index incrementing must not be interrupted */
- check_blockables_blocked_or_lose();
+ check_blockables_blocked_or_lose(0);
/* Get current Lisp state from context. */
#ifdef reg_ALLOC
+#ifdef LISP_FEATURE_SB_THREAD
+ thread->pseudo_atomic_bits =
+#else
dynamic_space_free_pointer =
- (lispobj *)(unsigned long)
+ (lispobj *)(uword_t)
+#endif
(*os_context_register_addr(context, reg_ALLOC));
- /* fprintf(stderr,"dynamic_space_free_pointer: %p\n", dynamic_space_free_pointer); */
-#if defined(LISP_FEATURE_ALPHA)
- if ((long)dynamic_space_free_pointer & 1) {
+/* fprintf(stderr,"dynamic_space_free_pointer: %p\n", */
+/* dynamic_space_free_pointer); */
+#if defined(LISP_FEATURE_ALPHA) || defined(LISP_FEATURE_MIPS)
+ if ((sword_t)dynamic_space_free_pointer & 1) {
lose("dead in fake_foreign_function_call, context = %x\n", context);
}
#endif
+/* why doesnt PPC and SPARC do something like this: */
+#if defined(LISP_FEATURE_HPPA)
+ if ((sword_t)dynamic_space_free_pointer & 4) {
+ lose("dead in fake_foreign_function_call, context = %x, d_s_f_p = %x\n", context, dynamic_space_free_pointer);
+ }
+#endif
#endif
#ifdef reg_BSP
- current_binding_stack_pointer =
- (lispobj *)(unsigned long)
- (*os_context_register_addr(context, reg_BSP));
+ set_binding_stack_pointer(thread,
+ *os_context_register_addr(context, reg_BSP));
#endif
build_fake_control_stack_frames(thread,context);
thread->interrupt_contexts[context_index] = context;
- /* no longer in Lisp now */
- foreign_function_call_active = 1;
+#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
+ /* x86oid targets don't maintain the foreign function call flag at
+ * all, so leave them to believe that they are never in foreign
+ * code. */
+ foreign_function_call_active_p(thread) = 1;
+#endif
}
/* blocks all blockable signals. If you are calling from a signal handler,
{
struct thread *thread=arch_os_get_current_thread();
/* Block all blockable signals. */
- block_blockable_signals();
+ block_blockable_signals(0, 0);
- /* going back into Lisp */
- foreign_function_call_active = 0;
+ foreign_function_call_active_p(thread) = 0;
/* Undo dynamic binding of FREE_INTERRUPT_CONTEXT_INDEX */
unbind(thread);
-#ifdef reg_ALLOC
+#if defined(reg_ALLOC) && !defined(LISP_FEATURE_SB_THREAD)
/* Put the dynamic space free pointer back into the context. */
*os_context_register_addr(context, reg_ALLOC) =
- (unsigned long) dynamic_space_free_pointer
+ (uword_t) dynamic_space_free_pointer
| (*os_context_register_addr(context, reg_ALLOC)
& LOWTAG_MASK);
/*
- ((unsigned long)(*os_context_register_addr(context, reg_ALLOC)) & ~LOWTAG_MASK)
- | ((unsigned long) dynamic_space_free_pointer & LOWTAG_MASK);
+ ((uword_t)(*os_context_register_addr(context, reg_ALLOC))
+ & ~LOWTAG_MASK)
+ | ((uword_t) dynamic_space_free_pointer & LOWTAG_MASK);
*/
#endif
+#if defined(reg_ALLOC) && defined(LISP_FEATURE_SB_THREAD)
+ /* Put the pseudo-atomic bits and dynamic space free pointer back
+ * into the context (p-a-bits for p-a, and dynamic space free
+ * pointer for ROOM). */
+ *os_context_register_addr(context, reg_ALLOC) =
+ (uword_t) dynamic_space_free_pointer
+ | (thread->pseudo_atomic_bits & LOWTAG_MASK);
+ /* And clear them so we don't get bit later by call-in/call-out
+ * not updating them. */
+ thread->pseudo_atomic_bits = 0;
+#endif
}
/* a handler for the signal caused by execution of a trap opcode
* signalling an internal error */
void
-interrupt_internal_error(int signal, siginfo_t *info, os_context_t *context,
- boolean continuable)
+interrupt_internal_error(os_context_t *context, boolean continuable)
{
lispobj context_sap;
/* Allocate the SAP object while the interrupts are still
* disabled. */
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+ unblock_gc_signals(0, 0);
+#endif
context_sap = alloc_sap(context);
-#ifndef LISP_FEATURE_WIN32
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
#endif
+#if defined(LISP_FEATURE_LINUX) && defined(LISP_FEATURE_MIPS)
+ /* Workaround for blocked SIGTRAP. */
+ {
+ sigset_t newset;
+ sigemptyset(&newset);
+ sigaddset(&newset, SIGTRAP);
+ thread_sigmask(SIG_UNBLOCK, &newset, 0);
+ }
+#endif
+
SHOW("in interrupt_internal_error");
-#ifdef QSHOW
+#if QSHOW == 2
/* Display some rudimentary debugging information about the
* error, so that even if the Lisp error handler gets badly
* confused, we have a chance to determine what's going on. */
describe_internal_error(context);
#endif
- funcall2(SymbolFunction(INTERNAL_ERROR), context_sap,
+ funcall2(StaticSymbolFunction(INTERNAL_ERROR), context_sap,
continuable ? T : NIL);
undo_fake_foreign_function_call(context); /* blocks signals again */
arch_skip_instruction(context);
}
+boolean
+interrupt_handler_pending_p(void)
+{
+ struct thread *thread = arch_os_get_current_thread();
+ struct interrupt_data *data = thread->interrupt_data;
+ return (data->pending_handler != 0);
+}
+
void
interrupt_handle_pending(os_context_t *context)
{
- struct thread *thread;
- struct interrupt_data *data;
+ /* There are three ways we can get here. First, if an interrupt
+ * occurs within pseudo-atomic, it will be deferred, and we'll
+ * trap to here at the end of the pseudo-atomic block. Second, if
+ * the GC (in alloc()) decides that a GC is required, it will set
+ * *GC-PENDING* and pseudo-atomic-interrupted if not *GC-INHIBIT*,
+ * and alloc() is always called from within pseudo-atomic, and
+ * thus we end up here again. Third, when calling GC-ON or at the
+ * end of a WITHOUT-GCING, MAYBE-HANDLE-PENDING-GC will trap to
+ * here if there is a pending GC. Fourth, ahem, at the end of
+ * WITHOUT-INTERRUPTS (bar complications with nesting).
+ *
+ * A fourth way happens with safepoints: In addition to a stop for
+ * GC that is pending, there are thruptions. Both mechanisms are
+ * mostly signal-free, yet also of an asynchronous nature, so it makes
+ * sense to let interrupt_handle_pending take care of running them:
+ * It gets run precisely at those places where it is safe to process
+ * pending asynchronous tasks. */
+
+ struct thread *thread = arch_os_get_current_thread();
+ struct interrupt_data *data = thread->interrupt_data;
+
+ if (arch_pseudo_atomic_atomic(context)) {
+ lose("Handling pending interrupt in pseudo atomic.");
+ }
FSHOW_SIGNAL((stderr, "/entering interrupt_handle_pending\n"));
- check_blockables_blocked_or_lose();
- thread=arch_os_get_current_thread();
- data=thread->interrupt_data;
-
- /* 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);
+ check_blockables_blocked_or_lose(0);
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+ /*
+ * (On safepoint builds, there is no gc_blocked_deferrables nor
+ * SIG_STOP_FOR_GC.)
+ */
+ /* If GC/SIG_STOP_FOR_GC struck during PA and there was no pending
+ * handler, then the pending mask was saved and
+ * gc_blocked_deferrables set. Hence, there can be no pending
+ * handler and it's safe to restore the pending mask.
+ *
+ * Note, that if gc_blocked_deferrables is false we may still have
+ * to GC. In this case, we are coming out of a WITHOUT-GCING or a
+ * pseudo atomic was interrupt be a deferrable first. */
+ if (data->gc_blocked_deferrables) {
+ if (data->pending_handler)
+ lose("GC blocked deferrables but still got a pending handler.");
+ if (SymbolValue(GC_INHIBIT,thread)!=NIL)
+ lose("GC blocked deferrables while GC is inhibited.");
+ /* Restore the saved signal mask from the original signal (the
+ * one that interrupted us during the critical section) into
+ * the os_context for the signal we're currently in the
+ * handler for. This should ensure that when we return from
+ * the handler the blocked signals are unblocked. */
+#ifndef LISP_FEATURE_WIN32
+ sigcopyset(os_context_sigmask_addr(context), &data->pending_mask);
+#endif
+ data->gc_blocked_deferrables = 0;
+ }
+#endif
if (SymbolValue(GC_INHIBIT,thread)==NIL) {
-#ifdef LISP_FEATURE_SB_THREAD
+ void *original_pending_handler = data->pending_handler;
+
+#ifdef LISP_FEATURE_SB_SAFEPOINT
+ /* handles the STOP_FOR_GC_PENDING case, plus THRUPTIONS */
+ if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL
+# ifdef LISP_FEATURE_SB_THRUPTION
+ || (SymbolValue(THRUPTION_PENDING,thread) != NIL
+ && SymbolValue(INTERRUPTS_ENABLED, thread) != NIL)
+# endif
+ )
+ /* We ought to take this chance to do a pitstop now. */
+ thread_in_lisp_raised(context);
+#elif defined(LISP_FEATURE_SB_THREAD)
if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL) {
- /* another thread has already initiated a gc, this attempt
- * might as well be cancelled */
- SetSymbolValue(GC_PENDING,NIL,thread);
- SetSymbolValue(STOP_FOR_GC_PENDING,NIL,thread);
+ /* STOP_FOR_GC_PENDING and GC_PENDING are cleared by
+ * the signal handler if it actually stops us. */
+ arch_clear_pseudo_atomic_interrupted(context);
sig_stop_for_gc_handler(SIG_STOP_FOR_GC,NULL,context);
} else
#endif
- if (SymbolValue(GC_PENDING,thread) != NIL) {
+ /* Test for T and not for != NIL since the value :IN-PROGRESS
+ * is used in SUB-GC as part of the mechanism to supress
+ * recursive gcs.*/
+ if (SymbolValue(GC_PENDING,thread) == T) {
+
+ /* Two reasons for doing this. First, if there is a
+ * pending handler we don't want to run. Second, we are
+ * going to clear pseudo atomic interrupted to avoid
+ * spurious trapping on every allocation in SUB_GC and
+ * having a pending handler with interrupts enabled and
+ * without pseudo atomic interrupted breaks an
+ * invariant. */
+ if (data->pending_handler) {
+ bind_variable(ALLOW_WITH_INTERRUPTS, NIL, thread);
+ bind_variable(INTERRUPTS_ENABLED, NIL, thread);
+ }
+
+ arch_clear_pseudo_atomic_interrupted(context);
+
/* GC_PENDING is cleared in SUB-GC, or if another thread
* is doing a gc already we will get a SIG_STOP_FOR_GC and
- * that will clear it. */
- interrupt_maybe_gc_int(0,NULL,context);
+ * that will clear it.
+ *
+ * If there is a pending handler or gc was triggerred in a
+ * signal handler then maybe_gc won't run POST_GC and will
+ * return normally. */
+ if (!maybe_gc(context))
+ lose("GC not inhibited but maybe_gc did not GC.");
+
+ if (data->pending_handler) {
+ unbind(thread);
+ unbind(thread);
+ }
+ } else if (SymbolValue(GC_PENDING,thread) != NIL) {
+ /* It's not NIL or T so GC_PENDING is :IN-PROGRESS. If
+ * GC-PENDING is not NIL then we cannot trap on pseudo
+ * atomic due to GC (see if(GC_PENDING) logic in
+ * cheneygc.c an gengcgc.c), plus there is a outer
+ * WITHOUT-INTERRUPTS SUB_GC, so how did we end up
+ * here? */
+ lose("Trapping to run pending handler while GC in progress.");
}
- check_blockables_blocked_or_lose();
- }
-
- /* we may be here only to do the gc stuff, if interrupts are
- * enabled run the pending handler */
- if (!((SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) ||
- (
-#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
- (!foreign_function_call_active) &&
-#endif
- arch_pseudo_atomic_atomic(context)))) {
-
- /* There may be no pending handler, because it was only a gc
- * that had to be executed or because pseudo atomic triggered
- * twice for a single interrupt. For the interested reader,
- * that may happen if an interrupt hits after the interrupted
- * flag is cleared but before pseduo-atomic is set and a
- * pseudo atomic is interrupted in that interrupt. */
- if (data->pending_handler) {
- /* If we're here as the result of a pseudo-atomic as opposed
- * to WITHOUT-INTERRUPTS, then INTERRUPT_PENDING is already
- * NIL, because maybe_defer_handler sets
- * PSEUDO_ATOMIC_INTERRUPTED only if interrupts are enabled.*/
- SetSymbolValue(INTERRUPT_PENDING, NIL,thread);
+ check_blockables_blocked_or_lose(0);
+
+ /* No GC shall be lost. If SUB_GC triggers another GC then
+ * that should be handled on the spot. */
+ if (SymbolValue(GC_PENDING,thread) != NIL)
+ lose("GC_PENDING after doing gc.");
+#ifdef THREADS_USING_GCSIGNAL
+ if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL)
+ lose("STOP_FOR_GC_PENDING after doing gc.");
+#endif
+ /* Check two things. First, that gc does not clobber a handler
+ * that's already pending. Second, that there is no interrupt
+ * lossage: if original_pending_handler was NULL then even if
+ * an interrupt arrived during GC (POST-GC, really) it was
+ * handled. */
+ if (original_pending_handler != data->pending_handler)
+ lose("pending handler changed in gc: %x -> %x.",
+ original_pending_handler, data->pending_handler);
+ }
#ifndef LISP_FEATURE_WIN32
- /* restore the saved signal mask from the original signal (the
- * one that interrupted us during the critical section) into the
- * os_context for the signal we're currently in the handler for.
- * This should ensure that when we return from the handler the
- * blocked signals are unblocked */
- sigcopyset(os_context_sigmask_addr(context), &data->pending_mask);
-
- sigemptyset(&data->pending_mask);
-#endif
- /* This will break on sparc linux: the deferred handler really wants
- * to be called with a void_context */
- run_deferred_handler(data,(void *)context);
- }
+ /* There may be no pending handler, because it was only a gc that
+ * had to be executed or because Lisp is a bit too eager to call
+ * DO-PENDING-INTERRUPT. */
+ if ((SymbolValue(INTERRUPTS_ENABLED,thread) != NIL) &&
+ (data->pending_handler)) {
+ /* No matter how we ended up here, clear both
+ * INTERRUPT_PENDING and pseudo atomic interrupted. It's safe
+ * because we checked above that there is no GC pending. */
+ SetSymbolValue(INTERRUPT_PENDING, NIL, thread);
+ arch_clear_pseudo_atomic_interrupted(context);
+ /* Restore the sigmask in the context. */
+ sigcopyset(os_context_sigmask_addr(context), &data->pending_mask);
+ run_deferred_handler(data, context);
}
+#ifdef LISP_FEATURE_SB_THRUPTION
+ if (SymbolValue(THRUPTION_PENDING,thread)==T)
+ /* Special case for the following situation: There is a
+ * thruption pending, but a signal had been deferred. The
+ * pitstop at the top of this function could only take care
+ * of GC, and skipped the thruption, so we need to try again
+ * now that INTERRUPT_PENDING and the sigmask have been
+ * reset. */
+ while (check_pending_thruptions(context))
+ ;
+#endif
+#endif
+#ifdef LISP_FEATURE_GENCGC
+ if (get_pseudo_atomic_interrupted(thread))
+ lose("pseudo_atomic_interrupted after interrupt_handle_pending\n");
+#endif
+ /* It is possible that the end of this function was reached
+ * without never actually doing anything, the tests in Lisp for
+ * when to call receive-pending-interrupt are not exact. */
+ FSHOW_SIGNAL((stderr, "/exiting interrupt_handle_pending\n"));
}
\f
-/*
- * the two main signal handlers:
- * interrupt_handle_now(..)
- * maybe_now_maybe_later(..)
- *
- * to which we have added interrupt_handle_now_handler(..). Why?
- * Well, mostly because the SPARC/Linux platform doesn't quite do
- * signals the way we want them done. The third argument in the
- * handler isn't filled in by the kernel properly, so we fix it up
- * ourselves in the arch_os_get_context(..) function; however, we only
- * want to do this when we first hit the handler, and not when
- * interrupt_handle_now(..) is being called from some other handler
- * (when the fixup will already have been done). -- CSR, 2002-07-23
- */
void
-interrupt_handle_now(int signal, siginfo_t *info, void *void_context)
+interrupt_handle_now(int signal, siginfo_t *info, os_context_t *context)
{
- os_context_t *context = (os_context_t*)void_context;
-#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
boolean were_in_lisp;
-#endif
union interrupt_handler handler;
- check_blockables_blocked_or_lose();
-
+ check_blockables_blocked_or_lose(0);
-#ifndef LISP_FEATURE_WIN32
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
if (sigismember(&deferrable_sigset,signal))
check_interrupts_enabled_or_lose(context);
#endif
-#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
- /* Under Linux on some architectures, we appear to have to restore
- the FPU control word from the context, as after the signal is
- delivered we appear to have a null FPU control word. */
- os_restore_fp_control(context);
-#endif
-
-
handler = interrupt_handlers[signal];
if (ARE_SAME_HANDLER(handler.c, SIG_IGN)) {
return;
}
-#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
- were_in_lisp = !foreign_function_call_active;
+ were_in_lisp = !foreign_function_call_active_p(arch_os_get_current_thread());
if (were_in_lisp)
-#endif
{
fake_foreign_function_call(context);
}
* 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);
+ lispobj info_sap, context_sap;
+
+#ifndef LISP_FEATURE_SB_SAFEPOINT
/* Leave deferrable signals blocked, the handler itself will
* allow signals again when it sees fit. */
-#ifdef LISP_FEATURE_SB_THREAD
- {
- sigset_t unblock;
- sigemptyset(&unblock);
- sigaddset(&unblock, SIG_STOP_FOR_GC);
-#ifdef SIG_RESUME_FROM_GC
- sigaddset(&unblock, SIG_RESUME_FROM_GC);
-#endif
- thread_sigmask(SIG_UNBLOCK, &unblock, 0);
- }
+ unblock_gc_signals(0, 0);
+#else
+ WITH_GC_AT_SAFEPOINTS_ONLY()
#endif
+ { // the block is needed for WITH_GC_AT_SAFEPOINTS_ONLY() to work
+ context_sap = alloc_sap(context);
+ info_sap = alloc_sap(info);
- FSHOW_SIGNAL((stderr,"/calling Lisp-level handler\n"));
+ FSHOW_SIGNAL((stderr,"/calling Lisp-level handler\n"));
- funcall3(handler.lisp,
- make_fixnum(signal),
- info_sap,
- context_sap);
+ funcall3(handler.lisp,
+ make_fixnum(signal),
+ info_sap,
+ context_sap);
+ }
} else {
+ /* This cannot happen in sane circumstances. */
FSHOW_SIGNAL((stderr,"/calling C-level handler\n"));
-#ifndef LISP_FEATURE_WIN32
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
/* Allow signals again. */
thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
+ (*handler.c)(signal, info, context);
#endif
-
- (*handler.c)(signal, info, void_context);
}
-#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
if (were_in_lisp)
-#endif
{
undo_fake_foreign_function_call(context); /* block signals again */
}
* already; we're just doing the Lisp-level processing now that we
* put off then */
static void
-run_deferred_handler(struct interrupt_data *data, void *v_context) {
+run_deferred_handler(struct interrupt_data *data, os_context_t *context)
+{
/* The pending_handler may enable interrupts and then another
* interrupt may hit, overwrite interrupt_data, so reset the
* pending handler before calling it. Trust the handler to finish
* with the siginfo before enabling interrupts. */
- void (*pending_handler) (int, siginfo_t*, void*)=data->pending_handler;
+ void (*pending_handler) (int, siginfo_t*, os_context_t*) =
+ data->pending_handler;
data->pending_handler=0;
- (*pending_handler)(data->pending_signal,&(data->pending_info), v_context);
+ FSHOW_SIGNAL((stderr, "/running deferred handler %p\n", pending_handler));
+ (*pending_handler)(data->pending_signal,&(data->pending_info), context);
}
#ifndef LISP_FEATURE_WIN32
{
struct thread *thread=arch_os_get_current_thread();
- check_blockables_blocked_or_lose();
+ check_blockables_blocked_or_lose(0);
if (SymbolValue(INTERRUPT_PENDING,thread) != NIL)
lose("interrupt already pending\n");
+ if (thread->interrupt_data->pending_handler)
+ lose("there is a pending handler already (PA)\n");
+ if (data->gc_blocked_deferrables)
+ lose("maybe_defer_handler: gc_blocked_deferrables true\n");
+ check_interrupt_context_or_lose(context);
/* If interrupts are disabled then INTERRUPT_PENDING is set and
* not PSEDUO_ATOMIC_INTERRUPTED. This is important for a pseudo
* atomic section inside a WITHOUT-INTERRUPTS.
+ *
+ * Also, if in_leaving_without_gcing_race_p then
+ * interrupt_handle_pending is going to be called soon, so
+ * stashing the signal away is safe.
*/
- if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) {
- store_signal_data_for_later(data,handler,signal,info,context);
- SetSymbolValue(INTERRUPT_PENDING, T,thread);
+ if ((SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) ||
+ in_leaving_without_gcing_race_p(thread)) {
FSHOW_SIGNAL((stderr,
- "/maybe_defer_handler(%x,%d),thread=%lu: deferred\n",
+ "/maybe_defer_handler(%x,%d): deferred (RACE=%d)\n",
(unsigned int)handler,signal,
- (unsigned long)thread->os_thread));
+ in_leaving_without_gcing_race_p(thread)));
+ store_signal_data_for_later(data,handler,signal,info,context);
+ SetSymbolValue(INTERRUPT_PENDING, T,thread);
+ check_interrupt_context_or_lose(context);
return 1;
}
- /* a slightly confusing test. arch_pseudo_atomic_atomic() doesn't
+ /* a slightly confusing test. arch_pseudo_atomic_atomic() doesn't
* actually use its argument for anything on x86, so this branch
* may succeed even when context is null (gencgc alloc()) */
- if (
-#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
- /* FIXME: this foreign_function_call_active test is dubious at
- * best. If a foreign call is made in a pseudo atomic section
- * (?) or more likely a pseudo atomic section is in a foreign
- * call then an interrupt is executed immediately. Maybe it
- * has to do with C code not maintaining pseudo atomic
- * properly. MG - 2005-08-10 */
- (!foreign_function_call_active) &&
-#endif
- arch_pseudo_atomic_atomic(context)) {
+ if (arch_pseudo_atomic_atomic(context)) {
+ FSHOW_SIGNAL((stderr,
+ "/maybe_defer_handler(%x,%d): deferred(PA)\n",
+ (unsigned int)handler,signal));
store_signal_data_for_later(data,handler,signal,info,context);
arch_set_pseudo_atomic_interrupted(context);
- FSHOW_SIGNAL((stderr,
- "/maybe_defer_handler(%x,%d),thread=%lu: deferred(PA)\n",
- (unsigned int)handler,signal,
- (unsigned long)thread->os_thread));
+ check_interrupt_context_or_lose(context);
return 1;
}
FSHOW_SIGNAL((stderr,
- "/maybe_defer_handler(%x,%d),thread=%lu: not deferred\n",
- (unsigned int)handler,signal,
- (unsigned long)thread->os_thread));
+ "/maybe_defer_handler(%x,%d): not deferred\n",
+ (unsigned int)handler,signal));
return 0;
}
if(info)
memcpy(&(data->pending_info), info, sizeof(siginfo_t));
- FSHOW_SIGNAL((stderr, "/store_signal_data_for_later: signal: %d\n", signal));
+ FSHOW_SIGNAL((stderr, "/store_signal_data_for_later: signal: %d\n",
+ signal));
- if(context) {
- /* the signal mask in the context (from before we were
- * interrupted) is copied to be restored when
- * run_deferred_handler happens. Then the usually-blocked
- * signals are added to the mask in the context so that we are
- * running with blocked signals when the handler returns */
- sigcopyset(&(data->pending_mask),os_context_sigmask_addr(context));
- sigaddset_deferrable(os_context_sigmask_addr(context));
- }
+ if(!context)
+ lose("Null context");
+
+ /* the signal mask in the context (from before we were
+ * interrupted) is copied to be restored when run_deferred_handler
+ * happens. Then the usually-blocked signals are added to the mask
+ * in the context so that we are running with blocked signals when
+ * the handler returns */
+ sigcopyset(&(data->pending_mask),os_context_sigmask_addr(context));
+ sigaddset_deferrable(os_context_sigmask_addr(context));
}
static void
maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context)
{
- os_context_t *context = arch_os_get_context(&void_context);
-
- struct thread *thread;
- struct interrupt_data *data;
-
- thread=arch_os_get_current_thread();
- data=thread->interrupt_data;
-
-#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
- os_restore_fp_control(context);
-#endif
-
- if(maybe_defer_handler(interrupt_handle_now,data,signal,info,context))
- return;
- interrupt_handle_now(signal, info, context);
-#ifdef LISP_FEATURE_DARWIN
- /* Work around G5 bug */
- DARWIN_FIX_CONTEXT(context);
-#endif
+ SAVE_ERRNO(signal,context,void_context);
+ struct thread *thread = arch_os_get_current_thread();
+ struct interrupt_data *data = thread->interrupt_data;
+ if(!maybe_defer_handler(interrupt_handle_now,data,signal,info,context))
+ interrupt_handle_now(signal, info, context);
+ RESTORE_ERRNO;
}
static void
-low_level_interrupt_handle_now(int signal, siginfo_t *info, void *void_context)
+low_level_interrupt_handle_now(int signal, siginfo_t *info,
+ os_context_t *context)
{
- os_context_t *context = (os_context_t*)void_context;
-
-#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
- os_restore_fp_control(context);
-#endif
-
- check_blockables_blocked_or_lose();
+ /* No FP control fixage needed, caller has done that. */
+ check_blockables_blocked_or_lose(0);
check_interrupts_enabled_or_lose(context);
- interrupt_low_level_handlers[signal](signal, info, void_context);
-#ifdef LISP_FEATURE_DARWIN
- /* Work around G5 bug */
- DARWIN_FIX_CONTEXT(context);
-#endif
+ (*interrupt_low_level_handlers[signal])(signal, info, context);
+ /* No Darwin context fixage needed, caller does that. */
}
static void
low_level_maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context)
{
- os_context_t *context = arch_os_get_context(&void_context);
- struct thread *thread;
- struct interrupt_data *data;
-
- thread=arch_os_get_current_thread();
- data=thread->interrupt_data;
-
-#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
- os_restore_fp_control(context);
-#endif
-
- if(maybe_defer_handler(low_level_interrupt_handle_now,data,
- signal,info,context))
- return;
- low_level_interrupt_handle_now(signal, info, context);
-#ifdef LISP_FEATURE_DARWIN
- /* Work around G5 bug */
- DARWIN_FIX_CONTEXT(context);
-#endif
+ SAVE_ERRNO(signal,context,void_context);
+ struct thread *thread = arch_os_get_current_thread();
+ struct interrupt_data *data = thread->interrupt_data;
+
+ if(!maybe_defer_handler(low_level_interrupt_handle_now,data,
+ signal,info,context))
+ low_level_interrupt_handle_now(signal, info, context);
+ RESTORE_ERRNO;
}
#endif
-#ifdef LISP_FEATURE_SB_THREAD
+#ifdef THREADS_USING_GCSIGNAL
+/* This function must not cons, because that may trigger a GC. */
void
-sig_stop_for_gc_handler(int signal, siginfo_t *info, void *void_context)
+sig_stop_for_gc_handler(int signal, siginfo_t *info, os_context_t *context)
{
- os_context_t *context = arch_os_get_context(&void_context);
-
struct thread *thread=arch_os_get_current_thread();
- sigset_t ss;
+ boolean was_in_lisp;
- if ((arch_pseudo_atomic_atomic(context) ||
- SymbolValue(GC_INHIBIT,thread) != NIL)) {
+ /* Test for GC_INHIBIT _first_, else we'd trap on every single
+ * pseudo atomic until gc is finally allowed. */
+ if (SymbolValue(GC_INHIBIT,thread) != NIL) {
+ FSHOW_SIGNAL((stderr, "sig_stop_for_gc deferred (*GC-INHIBIT*)\n"));
SetSymbolValue(STOP_FOR_GC_PENDING,T,thread);
- if (SymbolValue(GC_INHIBIT,thread) == NIL)
- arch_set_pseudo_atomic_interrupted(context);
- FSHOW_SIGNAL((stderr,"thread=%lu sig_stop_for_gc deferred\n",
- thread->os_thread));
- } else {
+ return;
+ } else if (arch_pseudo_atomic_atomic(context)) {
+ FSHOW_SIGNAL((stderr,"sig_stop_for_gc deferred (PA)\n"));
+ SetSymbolValue(STOP_FOR_GC_PENDING,T,thread);
+ arch_set_pseudo_atomic_interrupted(context);
+ maybe_save_gc_mask_and_block_deferrables
+ (os_context_sigmask_addr(context));
+ return;
+ }
+
+ FSHOW_SIGNAL((stderr, "/sig_stop_for_gc_handler\n"));
+
+ /* Not PA and GC not inhibited -- we can stop now. */
+
+ was_in_lisp = !foreign_function_call_active_p(arch_os_get_current_thread());
+
+ if (was_in_lisp) {
/* need the context stored so it can have registers scavenged */
fake_foreign_function_call(context);
+ }
+
+ /* Not pending anymore. */
+ SetSymbolValue(GC_PENDING,NIL,thread);
+ SetSymbolValue(STOP_FOR_GC_PENDING,NIL,thread);
+
+ /* Consider this: in a PA section GC is requested: GC_PENDING,
+ * pseudo_atomic_interrupted and gc_blocked_deferrables are set,
+ * deferrables are blocked then pseudo_atomic_atomic is cleared,
+ * but a SIG_STOP_FOR_GC arrives before trapping to
+ * interrupt_handle_pending. Here, GC_PENDING is cleared but
+ * pseudo_atomic_interrupted is not and we go on running with
+ * pseudo_atomic_interrupted but without a pending interrupt or
+ * GC. GC_BLOCKED_DEFERRABLES is also left at 1. So let's tidy it
+ * up. */
+ if (thread->interrupt_data->gc_blocked_deferrables) {
+ FSHOW_SIGNAL((stderr,"cleaning up after gc_blocked_deferrables\n"));
+ clear_pseudo_atomic_interrupted(thread);
+ sigcopyset(os_context_sigmask_addr(context),
+ &thread->interrupt_data->pending_mask);
+ thread->interrupt_data->gc_blocked_deferrables = 0;
+ }
- sigfillset(&ss); /* Block everything. */
- thread_sigmask(SIG_BLOCK,&ss,0);
+ if(thread_state(thread)!=STATE_RUNNING) {
+ lose("sig_stop_for_gc_handler: wrong thread state: %ld\n",
+ fixnum_value(thread->state));
+ }
- if(thread->state!=STATE_RUNNING) {
- lose("sig_stop_for_gc_handler: wrong thread state: %ld\n",
- fixnum_value(thread->state));
- }
- thread->state=STATE_SUSPENDED;
- FSHOW_SIGNAL((stderr,"thread=%lu suspended\n",thread->os_thread));
+ set_thread_state(thread,STATE_STOPPED);
+ FSHOW_SIGNAL((stderr,"suspended\n"));
-#if defined(SIG_RESUME_FROM_GC)
- sigemptyset(&ss); sigaddset(&ss,SIG_RESUME_FROM_GC);
-#else
- sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC);
-#endif
+ /* While waiting for gc to finish occupy ourselves with zeroing
+ * the unused portion of the control stack to reduce conservatism.
+ * On hypothetic platforms with threads and exact gc it is
+ * actually a must. */
+ scrub_control_stack();
- /* It is possible to get SIGCONT (and probably other
- * non-blockable signals) here. */
-#ifdef SIG_RESUME_FROM_GC
- {
- int sigret;
- do { sigwait(&ss, &sigret); }
- while (sigret != SIG_RESUME_FROM_GC);
- }
-#else
- while (sigwaitinfo(&ss,0) != SIG_STOP_FOR_GC);
-#endif
+ wait_for_thread_state_change(thread, STATE_STOPPED);
+ FSHOW_SIGNAL((stderr,"resumed\n"));
- 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",
- fixnum_value(thread->state));
- }
+ if(thread_state(thread)!=STATE_RUNNING) {
+ lose("sig_stop_for_gc_handler: wrong thread state on wakeup: %ld\n",
+ fixnum_value(thread_state(thread)));
+ }
+ if (was_in_lisp) {
undo_fake_foreign_function_call(context);
}
}
+
#endif
void
interrupt_handle_now_handler(int signal, siginfo_t *info, void *void_context)
{
- os_context_t *context = arch_os_get_context(&void_context);
- interrupt_handle_now(signal, info, context);
-#ifdef LISP_FEATURE_DARWIN
- DARWIN_FIX_CONTEXT(context);
+ SAVE_ERRNO(signal,context,void_context);
+#ifndef LISP_FEATURE_WIN32
+ if ((signal == SIGILL) || (signal == SIGBUS)
+#ifndef LISP_FEATURE_LINUX
+ || (signal == SIGEMT)
#endif
-}
-
-/*
- * stuff to detect and handle hitting the GC trigger
- */
-
-#ifndef LISP_FEATURE_GENCGC
-/* since GENCGC has its own way to record trigger */
-static boolean
-gc_trigger_hit(int signal, siginfo_t *info, os_context_t *context)
-{
- if (current_auto_gc_trigger == NULL)
- return 0;
- else{
- void *badaddr=arch_get_bad_addr(signal,info,context);
- return (badaddr >= (void *)current_auto_gc_trigger &&
- badaddr <((void *)current_dynamic_space + dynamic_space_size));
- }
-}
+ )
+ corruption_warning_and_maybe_lose("Signal %d received", signal);
#endif
+ interrupt_handle_now(signal, info, context);
+ RESTORE_ERRNO;
+}
/* manipulate the signal context and stack such that when the handler
* returns, it will call function instead of whatever it was doing
extern lispobj call_into_lisp(lispobj fun, lispobj *args, int nargs);
extern void post_signal_tramp(void);
extern void call_into_lisp_tramp(void);
+
void
-arrange_return_to_lisp_function(os_context_t *context, lispobj function)
+arrange_return_to_c_function(os_context_t *context,
+ call_into_lisp_lookalike funptr,
+ lispobj function)
{
+#if !(defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_SAFEPOINT))
+ check_gc_signals_unblocked_or_lose
+ (os_context_sigmask_addr(context));
+#endif
#if !(defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
void * fun=native_pointer(function);
void *code = &(((struct simple_fun *) fun)->code);
/* Build a stack frame showing `interrupted' so that the
* user's backtrace makes (as much) sense (as usual) */
- /* FIXME: what about restoring fp state? */
- /* FIXME: what about restoring errno? */
+ /* fp state is saved and restored by call_into_lisp */
+ /* FIXME: errno is not restored, but since current uses of this
+ * function only call Lisp code that signals an error, it's not
+ * much of a problem. In other words, running out of the control
+ * stack between a syscall and (GET-ERRNO) may clobber errno if
+ * something fails during signalling or in the handler. But I
+ * can't see what can go wrong as long as there is no CONTINUE
+ * like restart on them. */
#ifdef LISP_FEATURE_X86
/* Suppose the existence of some function that saved all
* registers, called call_into_lisp, then restored GP registers and
*(register_save_area + 7) = *os_context_register_addr(context,reg_EAX);
*(register_save_area + 8) = *context_eflags_addr(context);
- *os_context_pc_addr(context) = call_into_lisp_tramp;
- *os_context_register_addr(context,reg_ECX) = register_save_area;
+ *os_context_pc_addr(context) =
+ (os_context_register_t) funptr;
+ *os_context_register_addr(context,reg_ECX) =
+ (os_context_register_t) register_save_area;
#else
/* return address for call_into_lisp: */
#ifdef LISP_FEATURE_X86
#if !defined(LISP_FEATURE_DARWIN)
- *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp;
+ *os_context_pc_addr(context) = (os_context_register_t)funptr;
*os_context_register_addr(context,reg_ECX) = 0;
*os_context_register_addr(context,reg_EBP) = (os_context_register_t)(sp-2);
#ifdef __NetBSD__
#endif /* LISP_FEATURE_DARWIN */
#elif defined(LISP_FEATURE_X86_64)
- *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp;
+ *os_context_pc_addr(context) = (os_context_register_t)funptr;
*os_context_register_addr(context,reg_RCX) = 0;
*os_context_register_addr(context,reg_RBP) = (os_context_register_t)(sp-2);
*os_context_register_addr(context,reg_RSP) = (os_context_register_t)(sp-18);
*os_context_register_addr(context,reg_LIP) =
(os_context_register_t)(unsigned long)code;
*os_context_register_addr(context,reg_CFP) =
- (os_context_register_t)(unsigned long)current_control_frame_pointer;
+ (os_context_register_t)(unsigned long)access_control_frame_pointer(th);
#endif
#ifdef ARCH_HAS_NPC_REGISTER
*os_context_npc_addr(context) =
*os_context_register_addr(context,reg_CODE) =
(os_context_register_t)(fun + FUN_POINTER_LOWTAG);
#endif
+ FSHOW((stderr, "/arranged return to Lisp function (0x%lx)\n",
+ (long)function));
}
-#ifdef LISP_FEATURE_SB_THREAD
-
-/* 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)
+arrange_return_to_lisp_function(os_context_t *context, lispobj function)
{
- os_context_t *context = (os_context_t*)arch_os_get_context(&v_context);
-
- /* let the handler enable interrupts again when it sees fit */
- sigaddset_deferrable(os_context_sigmask_addr(context));
- arrange_return_to_lisp_function(context, SymbolFunction(RUN_INTERRUPTION));
-}
-
+#if defined(LISP_FEATURE_DARWIN) && defined(LISP_FEATURE_X86)
+ arrange_return_to_c_function(context, call_into_lisp_tramp, function);
+#else
+ arrange_return_to_c_function(context, call_into_lisp, function);
#endif
+}
+// x86-64 has an undefined_alien_function tramp in x86-64-assem.S
+#ifndef LISP_FEATURE_X86_64
/* KLUDGE: Theoretically the approach we use for undefined alien
* variables should work for functions as well, but on PPC/Darwin
* we get bus error at bogus addresses instead, hence this workaround,
* functions and variables.
*/
void
-undefined_alien_function() {
- funcall0(SymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR));
+undefined_alien_function(void)
+{
+ funcall0(StaticSymbolFunction(UNDEFINED_ALIEN_FUN_ERROR));
+}
+#endif
+
+void lower_thread_control_stack_guard_page(struct thread *th)
+{
+ protect_control_stack_guard_page(0, th);
+ protect_control_stack_return_guard_page(1, th);
+ th->control_stack_guard_page_protected = NIL;
+ fprintf(stderr, "INFO: Control stack guard page unprotected\n");
+}
+
+void reset_thread_control_stack_guard_page(struct thread *th)
+{
+ memset(CONTROL_STACK_GUARD_PAGE(th), 0, os_vm_page_size);
+ protect_control_stack_guard_page(1, th);
+ protect_control_stack_return_guard_page(0, th);
+ th->control_stack_guard_page_protected = T;
+ fprintf(stderr, "INFO: Control stack guard page reprotected\n");
+}
+
+/* Called from the REPL, too. */
+void reset_control_stack_guard_page(void)
+{
+ struct thread *th=arch_os_get_current_thread();
+ if (th->control_stack_guard_page_protected == NIL) {
+ reset_thread_control_stack_guard_page(th);
+ }
+}
+
+void lower_control_stack_guard_page(void)
+{
+ lower_thread_control_stack_guard_page(arch_os_get_current_thread());
}
boolean
{
struct thread *th=arch_os_get_current_thread();
- /* note the os_context hackery here. When the signal handler returns,
- * it won't go back to what it was doing ... */
- if(addr >= CONTROL_STACK_GUARD_PAGE(th) &&
- addr < CONTROL_STACK_GUARD_PAGE(th) + os_vm_page_size) {
+ if(addr >= CONTROL_STACK_HARD_GUARD_PAGE(th) &&
+ addr < CONTROL_STACK_HARD_GUARD_PAGE(th) + os_vm_page_size) {
+ lose("Control stack exhausted");
+ }
+ else if(addr >= CONTROL_STACK_GUARD_PAGE(th) &&
+ addr < CONTROL_STACK_GUARD_PAGE(th) + os_vm_page_size) {
/* We hit the end of the control stack: disable guard page
* protection so the error handler has some headroom, protect the
* previous page so that we can catch returns from the guard page
* and restore it. */
- protect_control_stack_guard_page(0);
- protect_control_stack_return_guard_page(1);
-
+ if (th->control_stack_guard_page_protected == NIL)
+ lose("control_stack_guard_page_protected NIL");
+ lower_control_stack_guard_page();
+#ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
+ /* For the unfortunate case, when the control stack is
+ * exhausted in a signal handler. */
+ unblock_signals_in_context_and_maybe_warn(context);
+#endif
arrange_return_to_lisp_function
- (context, SymbolFunction(CONTROL_STACK_EXHAUSTED_ERROR));
+ (context, StaticSymbolFunction(CONTROL_STACK_EXHAUSTED_ERROR));
return 1;
}
else if(addr >= CONTROL_STACK_RETURN_GUARD_PAGE(th) &&
* unprotect this one. This works even if we somehow missed
* the return-guard-page, and hit it on our way to new
* exhaustion instead. */
- protect_control_stack_guard_page(1);
- protect_control_stack_return_guard_page(0);
+ if (th->control_stack_guard_page_protected != NIL)
+ lose("control_stack_guard_page_protected not NIL");
+ reset_control_stack_guard_page();
return 1;
}
- else if (addr >= undefined_alien_address &&
- addr < undefined_alien_address + os_vm_page_size) {
+ else if(addr >= BINDING_STACK_HARD_GUARD_PAGE(th) &&
+ addr < BINDING_STACK_HARD_GUARD_PAGE(th) + os_vm_page_size) {
+ lose("Binding stack exhausted");
+ }
+ else if(addr >= BINDING_STACK_GUARD_PAGE(th) &&
+ addr < BINDING_STACK_GUARD_PAGE(th) + os_vm_page_size) {
+ protect_binding_stack_guard_page(0, NULL);
+ protect_binding_stack_return_guard_page(1, NULL);
+ fprintf(stderr, "INFO: Binding stack guard page unprotected\n");
+
+ /* For the unfortunate case, when the binding stack is
+ * exhausted in a signal handler. */
+ unblock_signals_in_context_and_maybe_warn(context);
arrange_return_to_lisp_function
- (context, SymbolFunction(UNDEFINED_ALIEN_VARIABLE_ERROR));
+ (context, StaticSymbolFunction(BINDING_STACK_EXHAUSTED_ERROR));
return 1;
}
- else return 0;
-}
-
-#ifndef LISP_FEATURE_GENCGC
-/* This function gets called from the SIGSEGV (for e.g. Linux, NetBSD, &
- * OpenBSD) or SIGBUS (for e.g. FreeBSD) handler. Here we check
- * whether the signal was due to treading on the mprotect()ed zone -
- * and if so, arrange for a GC to happen. */
-extern unsigned long bytes_consed_between_gcs; /* gc-common.c */
-
-boolean
-interrupt_maybe_gc(int signal, siginfo_t *info, void *void_context)
-{
- os_context_t *context=(os_context_t *) void_context;
-
- if(!foreign_function_call_active && gc_trigger_hit(signal, info, context)){
- struct thread *thread=arch_os_get_current_thread();
- clear_auto_gc_trigger();
- /* Don't flood the system with interrupts if the need to gc is
- * already noted. This can happen for example when SUB-GC
- * allocates or after a gc triggered in a WITHOUT-GCING. */
- if (SymbolValue(GC_PENDING,thread) == NIL) {
- if (SymbolValue(GC_INHIBIT,thread) == NIL) {
- if (arch_pseudo_atomic_atomic(context)) {
- /* set things up so that GC happens when we finish
- * the PA section */
- SetSymbolValue(GC_PENDING,T,thread);
- arch_set_pseudo_atomic_interrupted(context);
- } else {
- interrupt_maybe_gc_int(signal,info,void_context);
- }
- } else {
- SetSymbolValue(GC_PENDING,T,thread);
- }
- }
+ else if(addr >= BINDING_STACK_RETURN_GUARD_PAGE(th) &&
+ addr < BINDING_STACK_RETURN_GUARD_PAGE(th) + os_vm_page_size) {
+ protect_binding_stack_guard_page(1, NULL);
+ protect_binding_stack_return_guard_page(0, NULL);
+ fprintf(stderr, "INFO: Binding stack guard page reprotected\n");
return 1;
}
- return 0;
-}
-
-#endif
-
-/* this is also used by gencgc, in alloc() */
-boolean
-interrupt_maybe_gc_int(int signal, siginfo_t *info, void *void_context)
-{
- os_context_t *context=(os_context_t *) void_context;
-#ifndef LISP_FEATURE_WIN32
- struct thread *thread=arch_os_get_current_thread();
-#endif
-
- fake_foreign_function_call(context);
-
- /* SUB-GC may return without GCing if *GC-INHIBIT* is set, in
- * which case we will be running with no gc trigger barrier
- * thing for a while. But it shouldn't be long until the end
- * of WITHOUT-GCING.
- *
- * FIXME: It would be good to protect the end of dynamic space
- * and signal a storage condition from there.
- */
-
- /* Restore the signal mask from the interrupted context before
- * calling into Lisp if interrupts are enabled. Why not always?
- *
- * Suppose there is a WITHOUT-INTERRUPTS block far, far out. If an
- * interrupt hits while in SUB-GC, it is deferred and the
- * os_context_sigmask of that interrupt is set to block further
- * deferrable interrupts (until the first one is
- * handled). Unfortunately, that context refers to this place and
- * when we return from here the signals will not be blocked.
- *
- * A kludgy alternative is to propagate the sigmask change to the
- * outer context.
- */
-#ifndef LISP_FEATURE_WIN32
- if(SymbolValue(INTERRUPTS_ENABLED,thread)!=NIL) {
- thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
- check_gc_signals_unblocked_or_lose();
+ else if(addr >= ALIEN_STACK_HARD_GUARD_PAGE(th) &&
+ addr < ALIEN_STACK_HARD_GUARD_PAGE(th) + os_vm_page_size) {
+ lose("Alien stack exhausted");
}
- else
- unblock_gc_signals();
-#endif
- funcall0(SymbolFunction(SUB_GC));
- undo_fake_foreign_function_call(context);
- return 1;
+ else if(addr >= ALIEN_STACK_GUARD_PAGE(th) &&
+ addr < ALIEN_STACK_GUARD_PAGE(th) + os_vm_page_size) {
+ protect_alien_stack_guard_page(0, NULL);
+ protect_alien_stack_return_guard_page(1, NULL);
+ fprintf(stderr, "INFO: Alien stack guard page unprotected\n");
+
+ /* For the unfortunate case, when the alien stack is
+ * exhausted in a signal handler. */
+ unblock_signals_in_context_and_maybe_warn(context);
+ arrange_return_to_lisp_function
+ (context, StaticSymbolFunction(ALIEN_STACK_EXHAUSTED_ERROR));
+ return 1;
+ }
+ else if(addr >= ALIEN_STACK_RETURN_GUARD_PAGE(th) &&
+ addr < ALIEN_STACK_RETURN_GUARD_PAGE(th) + os_vm_page_size) {
+ protect_alien_stack_guard_page(1, NULL);
+ protect_alien_stack_return_guard_page(0, NULL);
+ fprintf(stderr, "INFO: Alien stack guard page reprotected\n");
+ return 1;
+ }
+ else if (addr >= undefined_alien_address &&
+ addr < undefined_alien_address + os_vm_page_size) {
+ arrange_return_to_lisp_function
+ (context, StaticSymbolFunction(UNDEFINED_ALIEN_VARIABLE_ERROR));
+ return 1;
+ }
+ else return 0;
}
-
\f
/*
* noise to install handlers
static void
sigaction_nodefer_test_handler(int signal, siginfo_t *info, void *void_context)
{
- sigset_t empty, current;
+ sigset_t current;
int i;
- sigemptyset(&empty);
- thread_sigmask(SIG_BLOCK, &empty, ¤t);
+ get_current_sigmask(¤t);
/* There should be exactly two blocked signals: the two we added
* to sa_mask when setting up the handler. NetBSD doesn't block
* the signal we're handling when SA_NODEFER is set; Linux before
}
static void
-see_if_sigaction_nodefer_works()
+see_if_sigaction_nodefer_works(void)
{
struct sigaction sa, old_sa;
#undef SA_NODEFER_TEST_BLOCK_SIGNAL
#undef SA_NODEFER_TEST_KILL_SIGNAL
+#if defined(LISP_FEATURE_SB_SAFEPOINT_STRICTLY) && !defined(LISP_FEATURE_WIN32)
+
+static void *
+signal_thread_trampoline(void *pthread_arg)
+{
+ int signo = (int) pthread_arg;
+ os_context_t fake_context;
+ siginfo_t fake_info;
+#ifdef LISP_FEATURE_PPC
+ mcontext_t uc_regs;
+#endif
+
+ memset(&fake_info, 0, sizeof(fake_info));
+ memset(&fake_context, 0, sizeof(fake_context));
+#ifdef LISP_FEATURE_PPC
+ memset(&uc_regs, 0, sizeof(uc_regs));
+ fake_context.uc_mcontext.uc_regs = &uc_regs;
+#endif
+
+ *os_context_pc_addr(&fake_context) = &signal_thread_trampoline;
+#ifdef ARCH_HAS_STACK_POINTER /* aka x86(-64) */
+ *os_context_sp_addr(&fake_context) = __builtin_frame_address(0);
+#endif
+
+ signal_handler_callback(interrupt_handlers[signo].lisp,
+ signo, &fake_info, &fake_context);
+ return 0;
+}
+
+static void
+sigprof_handler_trampoline(int signal, siginfo_t *info, void *void_context)
+{
+ SAVE_ERRNO(signal,context,void_context);
+ struct thread *self = arch_os_get_current_thread();
+
+ /* alloc() is not re-entrant and still uses pseudo atomic (even though
+ * inline allocation does not). In this case, give up. */
+ if (get_pseudo_atomic_atomic(self))
+ goto cleanup;
+
+ struct alloc_region tmp = self->alloc_region;
+ self->alloc_region = self->sprof_alloc_region;
+ self->sprof_alloc_region = tmp;
+
+ interrupt_handle_now_handler(signal, info, void_context);
+
+ /* And we're back. We know that the SIGPROF handler never unwinds
+ * non-locally, and can simply swap things back: */
+
+ tmp = self->alloc_region;
+ self->alloc_region = self->sprof_alloc_region;
+ self->sprof_alloc_region = tmp;
+
+cleanup:
+ ; /* Dear C compiler, it's OK to have a label here. */
+ RESTORE_ERRNO;
+}
+
+static void
+spawn_signal_thread_handler(int signal, siginfo_t *info, void *void_context)
+{
+ SAVE_ERRNO(signal,context,void_context);
+
+ pthread_attr_t attr;
+ pthread_t th;
+
+ if (pthread_attr_init(&attr))
+ goto lost;
+ if (pthread_attr_setstacksize(&attr, thread_control_stack_size))
+ goto lost;
+ if (pthread_create(&th, &attr, &signal_thread_trampoline, (void*) signal))
+ goto lost;
+ if (pthread_attr_destroy(&attr))
+ goto lost;
+
+ RESTORE_ERRNO;
+ return;
+
+lost:
+ lose("spawn_signal_thread_handler");
+}
+#endif
+
static void
unblock_me_trampoline(int signal, siginfo_t *info, void *void_context)
{
+ SAVE_ERRNO(signal,context,void_context);
sigset_t unblock;
sigemptyset(&unblock);
sigaddset(&unblock, signal);
thread_sigmask(SIG_UNBLOCK, &unblock, 0);
- interrupt_handle_now_handler(signal, info, void_context);
+ interrupt_handle_now(signal, info, context);
+ RESTORE_ERRNO;
}
static void
low_level_unblock_me_trampoline(int signal, siginfo_t *info, void *void_context)
{
+ SAVE_ERRNO(signal,context,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);
+ (*interrupt_low_level_handlers[signal])(signal, info, context);
+ RESTORE_ERRNO;
+}
+
+static void
+low_level_handle_now_handler(int signal, siginfo_t *info, void *void_context)
+{
+ SAVE_ERRNO(signal,context,void_context);
+ (*interrupt_low_level_handlers[signal])(signal, info, context);
+ RESTORE_ERRNO;
}
void
undoably_install_low_level_interrupt_handler (int signal,
- void handler(int,
- siginfo_t*,
- void*))
+ interrupt_handler_t handler)
{
struct sigaction sa;
}
if (ARE_SAME_HANDLER(handler, SIG_DFL))
- sa.sa_sigaction = handler;
+ sa.sa_sigaction = (void (*)(int, siginfo_t*, void*))handler;
else if (sigismember(&deferrable_sigset,signal))
sa.sa_sigaction = low_level_maybe_now_maybe_later;
- /* The use of a trampoline appears to break the
- arch_os_get_context() workaround for SPARC/Linux. For now,
- don't use the trampoline (and so be vulnerable to the problems
- that SA_NODEFER is meant to solve. */
-#if !(defined(LISP_FEATURE_SPARC) && defined(LISP_FEATURE_LINUX))
else if (!sigaction_nodefer_works &&
!sigismember(&blockable_sigset, signal))
sa.sa_sigaction = low_level_unblock_me_trampoline;
-#endif
else
- sa.sa_sigaction = handler;
+ sa.sa_sigaction = low_level_handle_now_handler;
+
+#ifdef LISP_FEATURE_SB_THRUPTION
+ /* It's in `deferrable_sigset' so that we block&unblock it properly,
+ * but we don't actually want to defer it. And if we put it only
+ * into blockable_sigset, we'd have to special-case it around thread
+ * creation at least. */
+ if (signal == SIGPIPE)
+ sa.sa_sigaction = low_level_handle_now_handler;
+#endif
sigcopyset(&sa.sa_mask, &blockable_sigset);
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_MEMORY_FAULT2
- || (signal==SIG_MEMORY_FAULT2)
-#endif
-#ifdef SIG_INTERRUPT_THREAD
- || (signal==SIG_INTERRUPT_THREAD)
-#endif
- )
+ if(signal==SIG_MEMORY_FAULT) {
sa.sa_flags |= SA_ONSTACK;
+# ifdef LISP_FEATURE_SB_SAFEPOINT
+ sigaddset(&sa.sa_mask, SIGRTMIN);
+ sigaddset(&sa.sa_mask, SIGRTMIN+1);
+# endif
+ }
#endif
sigaction(signal, &sa, NULL);
#endif
/* This is called from Lisp. */
-unsigned long
-install_handler(int signal, void handler(int, siginfo_t*, void*))
+uword_t
+install_handler(int signal, void handler(int, siginfo_t*, os_context_t*),
+ int synchronous)
{
#ifndef LISP_FEATURE_WIN32
struct sigaction sa;
- sigset_t old, new;
+ sigset_t old;
union interrupt_handler oldhandler;
FSHOW((stderr, "/entering POSIX install_handler(%d, ..)\n", signal));
- sigemptyset(&new);
- sigaddset(&new, signal);
- thread_sigmask(SIG_BLOCK, &new, &old);
+ block_blockable_signals(0, &old);
FSHOW((stderr, "/interrupt_low_level_handlers[signal]=%x\n",
(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))
- sa.sa_sigaction = handler;
+ sa.sa_sigaction = (void (*)(int, siginfo_t*, void*))handler;
+#ifdef LISP_FEATURE_SB_SAFEPOINT_STRICTLY
+ else if (signal == SIGPROF)
+ sa.sa_sigaction = sigprof_handler_trampoline;
+ else if (!synchronous)
+ sa.sa_sigaction = spawn_signal_thread_handler;
+#endif
else if (sigismember(&deferrable_sigset, signal))
sa.sa_sigaction = maybe_now_maybe_later;
else if (!sigaction_nodefer_works &&
FSHOW((stderr, "/leaving POSIX install_handler(%d, ..)\n", signal));
- return (unsigned long)oldhandler.lisp;
+ return (uword_t)oldhandler.lisp;
#else
/* Probably-wrong Win32 hack */
return 0;
#endif
}
+/* This must not go through lisp as it's allowed anytime, even when on
+ * the altstack. */
void
-interrupt_init()
+sigabrt_handler(int signal, siginfo_t *info, os_context_t *context)
{
-#ifndef LISP_FEATURE_WIN32
+ lose("SIGABRT received.\n");
+}
+
+void
+interrupt_init(void)
+{
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
int i;
SHOW("entering interrupt_init()");
+#ifndef LISP_FEATURE_WIN32
see_if_sigaction_nodefer_works();
+#endif
sigemptyset(&deferrable_sigset);
sigemptyset(&blockable_sigset);
+ sigemptyset(&gc_sigset);
sigaddset_deferrable(&deferrable_sigset);
sigaddset_blockable(&blockable_sigset);
+ sigaddset_gc(&gc_sigset);
+#endif
+#ifndef LISP_FEATURE_WIN32
/* Set up high level handler information. */
for (i = 0; i < NSIG; i++) {
interrupt_handlers[i].c =
* signal(..)-style one-argument handlers, which is OK
* because it works to call the 1-argument form where the
* 3-argument form is expected.) */
- (void (*)(int, siginfo_t*, void*))SIG_DFL;
+ (void (*)(int, siginfo_t*, os_context_t*))SIG_DFL;
}
-
- SHOW("returning from interrupt_init()");
+ undoably_install_low_level_interrupt_handler(SIGABRT, sigabrt_handler);
#endif
+ SHOW("returning from interrupt_init()");
}
#ifndef LISP_FEATURE_WIN32
lisp_memory_fault_error(os_context_t *context, os_vm_address_t addr)
{
/* FIXME: This is lossy: if we get another memory fault (eg. from
- * another thread) before lisp has read this, we the information.
+ * another thread) before lisp has read this, we lose the information.
* However, since this is mostly informative, we'll live with that for
* now -- some address is better then no address in this case.
*/
current_memory_fault_address = addr;
- arrange_return_to_lisp_function(context, SymbolFunction(MEMORY_FAULT_ERROR));
+ /* To allow debugging memory faults in signal handlers and such. */
+ corruption_warning_and_maybe_lose("Memory fault at %x (pc=%p, sp=%p)",
+ addr,
+ *os_context_pc_addr(context),
+#ifdef ARCH_HAS_STACK_POINTER
+ *os_context_sp_addr(context)
+#else
+ 0
+#endif
+ );
+ unblock_signals_in_context_and_maybe_warn(context);
+#ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
+ arrange_return_to_lisp_function(context,
+ StaticSymbolFunction(MEMORY_FAULT_ERROR));
+#else
+ funcall0(StaticSymbolFunction(MEMORY_FAULT_ERROR));
+#endif
+}
+#endif
+
+static void
+unhandled_trap_error(os_context_t *context)
+{
+ lispobj context_sap;
+ fake_foreign_function_call(context);
+#ifndef LISP_FEATURE_SB_SAFEPOINT
+ unblock_gc_signals(0, 0);
+#endif
+ context_sap = alloc_sap(context);
+#if !defined(LISP_FEATURE_WIN32) || defined(LISP_FEATURE_SB_THREAD)
+ thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
+#endif
+ funcall1(StaticSymbolFunction(UNHANDLED_TRAP_ERROR), context_sap);
+ lose("UNHANDLED-TRAP-ERROR fell through");
}
+
+/* Common logic for trapping instructions. How we actually handle each
+ * case is highly architecture dependent, but the overall shape is
+ * this. */
+void
+handle_trap(os_context_t *context, int trap)
+{
+ switch(trap) {
+#if !(defined(LISP_FEATURE_WIN32) && defined(LISP_FEATURE_SB_THREAD))
+ case trap_PendingInterrupt:
+ FSHOW((stderr, "/<trap pending interrupt>\n"));
+ arch_skip_instruction(context);
+ interrupt_handle_pending(context);
+ break;
+#endif
+ case trap_Error:
+ case trap_Cerror:
+ FSHOW((stderr, "/<trap error/cerror %d>\n", trap));
+ interrupt_internal_error(context, trap==trap_Cerror);
+ break;
+ case trap_Breakpoint:
+ arch_handle_breakpoint(context);
+ break;
+ case trap_FunEndBreakpoint:
+ arch_handle_fun_end_breakpoint(context);
+ break;
+#ifdef trap_AfterBreakpoint
+ case trap_AfterBreakpoint:
+ arch_handle_after_breakpoint(context);
+ break;
+#endif
+#ifdef trap_SingleStepAround
+ case trap_SingleStepAround:
+ case trap_SingleStepBefore:
+ arch_handle_single_step_trap(context, trap);
+ break;
+#endif
+#ifdef trap_GlobalSafepoint
+ case trap_GlobalSafepoint:
+ fake_foreign_function_call(context);
+ thread_in_lisp_raised(context);
+ undo_fake_foreign_function_call(context);
+ arch_skip_instruction(context);
+ break;
+ case trap_CspSafepoint:
+ fake_foreign_function_call(context);
+ thread_in_safety_transition(context);
+ undo_fake_foreign_function_call(context);
+ arch_skip_instruction(context);
+ break;
+#endif
+#if defined(LISP_FEATURE_SPARC) && defined(LISP_FEATURE_GENCGC)
+ case trap_Allocation:
+ arch_handle_allocation_trap(context);
+ arch_skip_instruction(context);
+ break;
#endif
+ case trap_Halt:
+ fake_foreign_function_call(context);
+ lose("%%PRIMITIVE HALT called; the party is over.\n");
+ default:
+ unhandled_trap_error(context);
+ }
+}
projects / sbcl.git / blobdiff