X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Finterrupt.c;h=294fc64abab1d3689527c27a21a7071eb2c630dd;hb=58513220fcf87e161a5e0d3fbadd76c45f27d584;hp=f2e9ceb3df43f466da6024ddcf67e585e4bc9b50;hpb=1c6e1e0ccbad4cefe1984f4a1a45d81181718f65;p=sbcl.git diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c index f2e9ceb..294fc64 100644 --- a/src/runtime/interrupt.c +++ b/src/runtime/interrupt.c @@ -22,7 +22,7 @@ * In that case, the Lisp-level handler is stored in interrupt_handlers[..] * and interrupt_low_level_handlers[..] is cleared. * - * However, some signals need special handling, e.g. + * However, some signals need special handling, e.g. * * o the SIGSEGV (for e.g. Linux) or SIGBUS (for e.g. FreeBSD) used by the * garbage collector to detect violations of write protection, @@ -36,20 +36,22 @@ * o the SIGTRAP (Linux/Alpha) which Lisp code uses to handle breakpoints, * pseudo-atomic sections, and some classes of error (e.g. "function * not defined"). This never goes anywhere near the Lisp handlers at all. - * See runtime/alpha-arch.c and code/signal.lisp - * + * See runtime/alpha-arch.c and code/signal.lisp + * * - WHN 20000728, dan 20010128 */ +#include "sbcl.h" #include #include #include #include #include +#ifndef LISP_FEATURE_WIN32 #include +#endif #include -#include "sbcl.h" #include "runtime.h" #include "arch.h" #include "os.h" @@ -57,133 +59,572 @@ #include "globals.h" #include "lispregs.h" #include "validate.h" -#include "monitor.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; +#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. */ + +#ifdef LISP_FEATURE_SB_THREAD +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 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 block_signals(sigset_t *what, sigset_t *where, sigset_t *old); +#endif -void sigaddset_blockable(sigset_t *s) +static boolean +maybe_resignal_to_lisp_thread(int signal, os_context_t *context) +{ +#ifdef LISP_FEATURE_SB_THREAD + 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); +#ifndef LISP_FEATURE_WIN32 +static void store_signal_data_for_later (struct interrupt_data *data, + void *handler, int signal, + siginfo_t *info, + os_context_t *context); + + +/* 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) + 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 +} + + +/* 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, SIGURG); - sigaddset(s, SIGFPE); 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); - 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 LISP_FEATURE_SB_THREAD - sigaddset(s, SIG_STOP_FOR_GC); - sigaddset(s, SIG_INTERRUPT_THREAD); + sigaddset(sigset,SIG_STOP_FOR_GC); #endif } -static sigset_t blockable_sigset; +/* initialized in interrupt_init */ +sigset_t deferrable_sigset; +sigset_t blockable_sigset; +sigset_t gc_sigset; + +#endif -inline static void check_blockables_blocked_or_lose() +#if !defined(LISP_FEATURE_WIN32) +boolean +deferrables_blocked_p(sigset_t *sigset) { - /* 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=0;iinterrupt_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 +} + +/* 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) +{ +#ifndef LISP_FEATURE_WIN32 + 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(LISP_FEATURE_PPC) + 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); + /* If deferrables are unblocked then we are open to signals + * that run lisp code. */ + check_gc_signals_unblocked_or_lose(sigset); + } +#endif +} /* * utility routines used by various signal handlers */ -void +static void build_fake_control_stack_frames(struct thread *th,os_context_t *context) { #ifndef LISP_FEATURE_C_STACK_IS_CONTROL_STACK - + lispobj oldcont; /* Build a fake stack frame or frames */ current_control_frame_pointer = - (lispobj *)(*os_context_register_addr(context, reg_CSP)); - if ((lispobj *)(*os_context_register_addr(context, reg_CFP)) - == current_control_frame_pointer) { + (lispobj *)(unsigned long) + (*os_context_register_addr(context, reg_CSP)); + if ((lispobj *)(unsigned long) + (*os_context_register_addr(context, reg_CFP)) + == current_control_frame_pointer) { /* 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) { + == FUN_POINTER_LOWTAG) { /* We have called, but not built the new frame, so * build it for them. */ current_control_frame_pointer[0] = - *os_context_register_addr(context, reg_OCFP); + *os_context_register_addr(context, reg_OCFP); current_control_frame_pointer[1] = - *os_context_register_addr(context, reg_LRA); + *os_context_register_addr(context, reg_LRA); current_control_frame_pointer += 8; /* Build our frame on top of it. */ oldcont = (lispobj)(*os_context_register_addr(context, reg_CFP)); @@ -208,10 +649,12 @@ build_fake_control_stack_frames(struct thread *th,os_context_t *context) current_control_frame_pointer[0] = oldcont; current_control_frame_pointer[1] = NIL; current_control_frame_pointer[2] = - (lispobj)(*os_context_register_addr(context, reg_CODE)); + (lispobj)(*os_context_register_addr(context, reg_CODE)); #endif } +/* Stores the context for gc to scavange and builds fake stack + * frames. */ void fake_foreign_function_call(os_context_t *context) { @@ -219,21 +662,31 @@ fake_foreign_function_call(os_context_t *context) 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 dynamic_space_free_pointer = - (lispobj *)(*os_context_register_addr(context, reg_ALLOC)); -#if defined(LISP_FEATURE_ALPHA) + (lispobj *)(unsigned long) + (*os_context_register_addr(context, reg_ALLOC)); +/* fprintf(stderr,"dynamic_space_free_pointer: %p\n", */ +/* dynamic_space_free_pointer); */ +#if defined(LISP_FEATURE_ALPHA) || defined(LISP_FEATURE_MIPS) if ((long)dynamic_space_free_pointer & 1) { - lose("dead in fake_foreign_function_call, context = %x", context); + 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 ((long)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 *)(*os_context_register_addr(context, reg_BSP)); + (lispobj *)(unsigned long) + (*os_context_register_addr(context, reg_BSP)); #endif build_fake_control_stack_frames(thread,context); @@ -241,34 +694,35 @@ fake_foreign_function_call(os_context_t *context) /* Do dynamic binding of the active interrupt context index * and save the context in the context array. */ context_index = - fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)); - + fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)); + if (context_index >= MAX_INTERRUPTS) { - lose("maximum interrupt nesting depth (%d) exceeded", MAX_INTERRUPTS); + lose("maximum interrupt nesting depth (%d) exceeded\n", MAX_INTERRUPTS); } bind_variable(FREE_INTERRUPT_CONTEXT_INDEX, - make_fixnum(context_index + 1),thread); + make_fixnum(context_index + 1),thread); thread->interrupt_contexts[context_index] = context; - /* no longer in Lisp now */ +#ifdef FOREIGN_FUNCTION_CALL_FLAG foreign_function_call_active = 1; +#endif } /* 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 + * 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) { struct thread *thread=arch_os_get_current_thread(); /* Block all blockable signals. */ - block_blockable_signals(); + block_blockable_signals(0, 0); - /* going back into Lisp */ +#ifdef FOREIGN_FUNCTION_CALL_FLAG foreign_function_call_active = 0; +#endif /* Undo dynamic binding of FREE_INTERRUPT_CONTEXT_INDEX */ unbind(thread); @@ -276,129 +730,249 @@ undo_fake_foreign_function_call(os_context_t *context) #ifdef reg_ALLOC /* Put the dynamic space free pointer back into the context. */ *os_context_register_addr(context, reg_ALLOC) = - (unsigned long) dynamic_space_free_pointer; + (unsigned long) 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); + */ #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 = 0; + lispobj context_sap; - check_blockables_blocked_or_lose(); fake_foreign_function_call(context); + if (!internal_errors_enabled) { + describe_internal_error(context); + /* There's no good way to recover from an internal error + * before the Lisp error handling mechanism is set up. */ + lose("internal error too early in init, can't recover\n"); + } + /* Allocate the SAP object while the interrupts are still * disabled. */ - if (internal_errors_enabled) { - context_sap = alloc_sap(context); - } + unblock_gc_signals(0, 0); + context_sap = alloc_sap(context); +#ifndef LISP_FEATURE_WIN32 thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); - - if (internal_errors_enabled) { - SHOW("in interrupt_internal_error"); -#ifdef QSHOW - /* 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, - continuable ? T : NIL); - } else { - describe_internal_error(context); - /* There's no good way to recover from an internal error - * before the Lisp error handling mechanism is set up. */ - lose("internal error too early in init, can't recover"); + +#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"); +#if QSHOW + /* 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(StaticSymbolFunction(INTERNAL_ERROR), context_sap, + continuable ? T : NIL); + undo_fake_foreign_function_call(context); /* blocks signals again */ - if (continuable) { - arch_skip_instruction(context); - } + if (continuable) + 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). */ + + /* Win32 only needs to handle the GC cases (for now?) */ + + 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."); + } - check_blockables_blocked_or_lose(); - check_interrupts_enabled_or_lose(context); + FSHOW_SIGNAL((stderr, "/entering interrupt_handle_pending\n")); - thread=arch_os_get_current_thread(); - data=thread->interrupt_data; - - /* Pseudo atomic may trigger several times for a single interrupt, - * and while without-interrupts should not, a false trigger by - * pseudo-atomic may eat a pending handler even from - * without-interrupts. */ - 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); - - /* 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 */ + check_blockables_blocked_or_lose(0); + + /* 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; + } - sigemptyset(&data->pending_mask); - /* This will break on sparc linux: the deferred handler really wants - * to be called with a void_context */ - run_deferred_handler(data,(void *)context); + if (SymbolValue(GC_INHIBIT,thread)==NIL) { + void *original_pending_handler = data->pending_handler; + +#ifdef LISP_FEATURE_SB_THREAD + if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL) { + /* 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 + /* 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. + * + * 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(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 LISP_FEATURE_SB_THREAD + 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 -> %d.", + original_pending_handler, data->pending_handler); } + +#ifndef LISP_FEATURE_WIN32 + /* 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); + } +#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")); } -/* - * 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; - struct thread *thread=arch_os_get_current_thread(); -#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) +#ifdef FOREIGN_FUNCTION_CALL_FLAG boolean were_in_lisp; #endif union interrupt_handler handler; - check_blockables_blocked_or_lose(); - check_interrupts_enabled_or_lose(context); -#ifdef LISP_FEATURE_LINUX - /* 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 = thread->interrupt_data->interrupt_handlers[signal]; + check_blockables_blocked_or_lose(0); + +#ifndef LISP_FEATURE_WIN32 + if (sigismember(&deferrable_sigset,signal)) + check_interrupts_enabled_or_lose(context); +#endif + + handler = interrupt_handlers[signal]; if (ARE_SAME_HANDLER(handler.c, SIG_IGN)) { - return; + return; } - -#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) + +#ifdef FOREIGN_FUNCTION_CALL_FLAG were_in_lisp = !foreign_function_call_active; if (were_in_lisp) #endif @@ -406,69 +980,68 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) fake_foreign_function_call(context); } -#ifdef QSHOW_SIGNALS - FSHOW((stderr, - "/entering interrupt_handle_now(%d, info, context)\n", - signal)); -#endif + FSHOW_SIGNAL((stderr, + "/entering interrupt_handle_now(%d, info, context)\n", + signal)); if (ARE_SAME_HANDLER(handler.c, SIG_DFL)) { - /* This can happen if someone tries to ignore or default one - * of the signals we need for runtime support, and the runtime - * support decides to pass on it. */ - lose("no handler for signal %d in interrupt_handle_now(..)", signal); + /* This can happen if someone tries to ignore or default one + * of the signals we need for runtime support, and the runtime + * support decides to pass on it. */ + lose("no handler for signal %d in interrupt_handle_now(..)\n", signal); } else if (lowtag_of(handler.lisp) == FUN_POINTER_LOWTAG) { - /* Once we've decided what to do about contexts in a - * return-elsewhere world (the original context will no longer - * be available; should we copy it or was nobody using it anyway?) - * then we should convert this to return-elsewhere */ + /* Once we've decided what to do about contexts in a + * return-elsewhere world (the original context will no longer + * be available; should we copy it or was nobody using it anyway?) + * then we should convert this to return-elsewhere */ /* CMUCL comment said "Allocate the SAPs while the interrupts - * are still disabled.". I (dan, 2003.08.21) assume this is - * because we're not in pseudoatomic and allocation shouldn't - * be interrupted. In which case it's no longer an issue as - * all our allocation from C now goes through a PA wrapper, - * but still, doesn't hurt */ - - lispobj info_sap,context_sap = alloc_sap(context); + * are still disabled.". I (dan, 2003.08.21) assume this is + * because we're not in pseudoatomic and allocation shouldn't + * be interrupted. In which case it's no longer an issue as + * all our allocation from C now goes through a PA wrapper, + * but still, doesn't hurt. + * + * Yeah, but non-gencgc platforms don't really wrap allocation + * in PA. MG - 2005-08-29 */ + + lispobj info_sap, context_sap; + /* Leave deferrable signals blocked, the handler itself will + * allow signals again when it sees fit. */ + unblock_gc_signals(0, 0); + context_sap = alloc_sap(context); info_sap = alloc_sap(info); - /* Allow signals again. */ - thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); -#ifdef QSHOW_SIGNALS - SHOW("calling Lisp-level handler"); -#endif + FSHOW_SIGNAL((stderr,"/calling Lisp-level handler\n")); funcall3(handler.lisp, - make_fixnum(signal), - info_sap, - context_sap); + make_fixnum(signal), + info_sap, + context_sap); } else { + /* This cannot happen in sane circumstances. */ -#ifdef QSHOW_SIGNALS - SHOW("calling C-level handler"); -#endif + FSHOW_SIGNAL((stderr,"/calling C-level handler\n")); +#ifndef LISP_FEATURE_WIN32 /* Allow signals again. */ thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); - - (*handler.c)(signal, info, void_context); +#endif + (*handler.c)(signal, info, context); } -#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) +#ifdef FOREIGN_FUNCTION_CALL_FLAG if (were_in_lisp) #endif { undo_fake_foreign_function_call(context); /* block signals again */ } -#ifdef QSHOW_SIGNALS - FSHOW((stderr, - "/returning from interrupt_handle_now(%d, info, context)\n", - signal)); -#endif + FSHOW_SIGNAL((stderr, + "/returning from interrupt_handle_now(%d, info, context)\n", + signal)); } /* This is called at the end of a critical section if the indications @@ -476,72 +1049,78 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) * 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 */ +static void +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*, os_context_t*) = + data->pending_handler; -void -run_deferred_handler(struct interrupt_data *data, void *v_context) { - /* The pending_handler may enable interrupts (see - * interrupt_maybe_gc_int) 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; 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 boolean maybe_defer_handler(void *handler, struct interrupt_data *data, - int signal, siginfo_t *info, os_context_t *context) + int signal, siginfo_t *info, os_context_t *context) { 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"); + 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. + * 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); + if ((SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) || + in_leaving_without_gcing_race_p(thread)) { + FSHOW_SIGNAL((stderr, + "/maybe_defer_handler(%x,%d): deferred (RACE=%d)\n", + (unsigned int)handler,signal, + in_leaving_without_gcing_race_p(thread))); + store_signal_data_for_later(data,handler,signal,info,context); SetSymbolValue(INTERRUPT_PENDING, T,thread); -#ifdef QSHOW_SIGNALS - FSHOW((stderr, - "/maybe_defer_handler(%x,%d),thread=%ld: deferred\n", - (unsigned int)handler,signal,thread->os_thread)); -#endif - return 1; - } - /* a slightly confusing test. arch_pseudo_atomic_atomic() doesn't + check_interrupt_context_or_lose(context); + return 1; + } + /* 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) - (!foreign_function_call_active) && -#endif - arch_pseudo_atomic_atomic(context)) { - store_signal_data_for_later(data,handler,signal,info,context); - arch_set_pseudo_atomic_interrupted(context); -#ifdef QSHOW_SIGNALS - FSHOW((stderr, - "/maybe_defer_handler(%x,%d),thread=%ld: deferred(PA)\n", - (unsigned int)handler,signal,thread->os_thread)); -#endif - return 1; + 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); + check_interrupt_context_or_lose(context); + return 1; } -#ifdef QSHOW_SIGNALS - FSHOW((stderr, - "/maybe_defer_handler(%x,%d),thread=%ld: not deferred\n", - (unsigned int)handler,signal,thread->os_thread)); -#endif + FSHOW_SIGNAL((stderr, + "/maybe_defer_handler(%x,%d): not deferred\n", + (unsigned int)handler,signal)); return 0; } static void store_signal_data_for_later (struct interrupt_data *data, void *handler, - int signal, - siginfo_t *info, os_context_t *context) + int signal, + siginfo_t *info, os_context_t *context) { if (data->pending_handler) lose("tried to overwrite pending interrupt handler %x with %x\n", @@ -551,141 +1130,152 @@ store_signal_data_for_later (struct interrupt_data *data, void *handler, data->pending_handler = handler; data->pending_signal = signal; if(info) - memcpy(&(data->pending_info), info, sizeof(siginfo_t)); - 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_blockable(os_context_sigmask_addr(context)); - } + memcpy(&(data->pending_info), info, sizeof(siginfo_t)); + + FSHOW_SIGNAL((stderr, "/store_signal_data_for_later: signal: %d\n", + signal)); + + 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=arch_os_get_current_thread(); - struct interrupt_data *data=thread->interrupt_data; -#ifdef LISP_FEATURE_LINUX - 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; - struct thread *thread=arch_os_get_current_thread(); - -#ifdef LISP_FEATURE_LINUX - 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); - (*thread->interrupt_data->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=arch_os_get_current_thread(); - struct interrupt_data *data=thread->interrupt_data; -#ifdef LISP_FEATURE_LINUX - 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 + +/* 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; - int i; - + + /* 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); + 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. */ + /* need the context stored so it can have registers scavenged */ - fake_foreign_function_call(context); + fake_foreign_function_call(context); - sigemptyset(&ss); - for(i=1;iinterrupt_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; + } - /* 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) { + if(thread_state(thread)!=STATE_RUNNING) { lose("sig_stop_for_gc_handler: wrong thread state: %ld\n", fixnum_value(thread->state)); } - thread->state=STATE_SUSPENDED; - sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC); - sigwaitinfo(&ss,0); - if(thread->state!=STATE_SUSPENDED) { + set_thread_state(thread,STATE_SUSPENDED); + FSHOW_SIGNAL((stderr,"suspended\n")); + + /* 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(); + + wait_for_thread_state_change(thread, STATE_SUSPENDED); + FSHOW_SIGNAL((stderr,"resumed\n")); + + if(thread_state(thread)!=STATE_RUNNING) { lose("sig_stop_for_gc_handler: wrong thread state on wakeup: %ld\n", - fixnum_value(thread->state)); + fixnum_value(thread_state(thread))); } - thread->state=STATE_RUNNING; 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 recieved", 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 @@ -693,23 +1283,35 @@ gc_trigger_hit(int signal, siginfo_t *info, os_context_t *context) */ #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) +extern void call_into_lisp_tramp(void); +void +arrange_return_to_lisp_function(os_context_t *context, lispobj function) { +#ifndef LISP_FEATURE_WIN32 + 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); -#endif +#endif /* 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 @@ -726,8 +1328,8 @@ void arrange_return_to_lisp_function(os_context_t *context, lispobj function) addl $12,%esp popal popfl - leave - ret + leave + ret * What we do here is set up the stack that call_into_lisp would * expect to see if it had been called by this code, and frob the @@ -742,10 +1344,42 @@ void arrange_return_to_lisp_function(os_context_t *context, lispobj function) u32 *sp=(u32 *)*os_context_register_addr(context,reg_ESP); - *(sp-15) = post_signal_tramp; /* return address for call_into_lisp */ +#if defined(LISP_FEATURE_DARWIN) + u32 *register_save_area = (u32 *)os_validate(0, 0x40); + + FSHOW_SIGNAL((stderr, "/arrange_return_to_lisp_function: preparing to go to function %x, sp: %x\n", function, sp)); + FSHOW_SIGNAL((stderr, "/arrange_return_to_lisp_function: context: %x, &context %x\n", context, &context)); + + /* 1. os_validate (malloc/mmap) register_save_block + * 2. copy register state into register_save_block + * 3. put a pointer to register_save_block in a register in the context + * 4. set the context's EIP to point to a trampoline which: + * a. builds the fake stack frame from the block + * b. frees the block + * c. calls the function + */ + + *register_save_area = *os_context_pc_addr(context); + *(register_save_area + 1) = function; + *(register_save_area + 2) = *os_context_register_addr(context,reg_EDI); + *(register_save_area + 3) = *os_context_register_addr(context,reg_ESI); + *(register_save_area + 4) = *os_context_register_addr(context,reg_EDX); + *(register_save_area + 5) = *os_context_register_addr(context,reg_ECX); + *(register_save_area + 6) = *os_context_register_addr(context,reg_EBX); + *(register_save_area + 7) = *os_context_register_addr(context,reg_EAX); + *(register_save_area + 8) = *context_eflags_addr(context); + + *os_context_pc_addr(context) = + (os_context_register_t) call_into_lisp_tramp; + *os_context_register_addr(context,reg_ECX) = + (os_context_register_t) register_save_area; +#else + + /* return address for call_into_lisp: */ + *(sp-15) = (u32)post_signal_tramp; *(sp-14) = function; /* args for call_into_lisp : function*/ - *(sp-13) = 0; /* arg array */ - *(sp-12) = 0; /* no. args */ + *(sp-13) = 0; /* arg array */ + *(sp-12) = 0; /* no. args */ /* this order matches that used in POPAD */ *(sp-11)=*os_context_register_addr(context,reg_EDI); *(sp-10)=*os_context_register_addr(context,reg_ESI); @@ -762,9 +1396,13 @@ void arrange_return_to_lisp_function(os_context_t *context, lispobj function) *(sp-2)=*os_context_register_addr(context,reg_EBP); *(sp-1)=*os_context_pc_addr(context); +#endif + #elif defined(LISP_FEATURE_X86_64) u64 *sp=(u64 *)*os_context_register_addr(context,reg_RSP); - *(sp-18) = post_signal_tramp; /* return address for call_into_lisp */ + + /* return address for call_into_lisp: */ + *(sp-18) = (u64)post_signal_tramp; *(sp-17)=*os_context_register_addr(context,reg_R15); *(sp-16)=*os_context_register_addr(context,reg_R14); @@ -785,98 +1423,110 @@ void arrange_return_to_lisp_function(os_context_t *context, lispobj function) *(sp-2)=*os_context_register_addr(context,reg_RBP); *(sp-1)=*os_context_pc_addr(context); - *os_context_register_addr(context,reg_RDI) = function; /* function */ + *os_context_register_addr(context,reg_RDI) = + (os_context_register_t)function; /* function */ *os_context_register_addr(context,reg_RSI) = 0; /* arg. array */ *os_context_register_addr(context,reg_RDX) = 0; /* no. args */ -#else +#else struct thread *th=arch_os_get_current_thread(); build_fake_control_stack_frames(th,context); #endif #ifdef LISP_FEATURE_X86 - *os_context_pc_addr(context) = call_into_lisp; - *os_context_register_addr(context,reg_ECX) = 0; - *os_context_register_addr(context,reg_EBP) = sp-2; -#ifdef __NetBSD__ - *os_context_register_addr(context,reg_UESP) = sp-15; + +#if !defined(LISP_FEATURE_DARWIN) + *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp; + *os_context_register_addr(context,reg_ECX) = 0; + *os_context_register_addr(context,reg_EBP) = (os_context_register_t)(sp-2); +#ifdef __NetBSD__ + *os_context_register_addr(context,reg_UESP) = + (os_context_register_t)(sp-15); #else - *os_context_register_addr(context,reg_ESP) = sp-15; -#endif + *os_context_register_addr(context,reg_ESP) = (os_context_register_t)(sp-15); +#endif /* __NETBSD__ */ +#endif /* LISP_FEATURE_DARWIN */ + #elif defined(LISP_FEATURE_X86_64) - *os_context_pc_addr(context) = call_into_lisp; - *os_context_register_addr(context,reg_RCX) = 0; - *os_context_register_addr(context,reg_RBP) = sp-2; - *os_context_register_addr(context,reg_RSP) = sp-18; + *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp; + *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); #else /* this much of the calling convention is common to all non-x86 ports */ - *os_context_pc_addr(context) = code; - *os_context_register_addr(context,reg_NARGS) = 0; - *os_context_register_addr(context,reg_LIP) = code; - *os_context_register_addr(context,reg_CFP) = - current_control_frame_pointer; + *os_context_pc_addr(context) = (os_context_register_t)(unsigned long)code; + *os_context_register_addr(context,reg_NARGS) = 0; + *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; #endif #ifdef ARCH_HAS_NPC_REGISTER *os_context_npc_addr(context) = - 4 + *os_context_pc_addr(context); + 4 + *os_context_pc_addr(context); #endif #ifdef LISP_FEATURE_SPARC - *os_context_register_addr(context,reg_CODE) = - fun + FUN_POINTER_LOWTAG; + *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 -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); - /* The order of interrupt execution is peculiar. If thread A - * interrupts thread B with I1, I2 and B for some reason recieves - * I1 when FUN2 is already on the list, then it is FUN2 that gets - * to run first. But when FUN2 is run SIG_INTERRUPT_THREAD is - * enabled again and I2 hits pretty soon in FUN2 and run - * FUN1. This is of course just one scenario, and the order of - * thread interrupt execution is undefined. */ - struct thread *th=arch_os_get_current_thread(); - struct cons *c; - if (th->state != STATE_RUNNING) - lose("interrupt_thread_handler: thread %ld in wrong state: %d\n", - th->os_thread,fixnum_value(th->state)); - get_spinlock(&th->interrupt_fun_lock,(long)th); - c=((struct cons *)native_pointer(th->interrupt_fun)); - arrange_return_to_lisp_function(context,c->car); - th->interrupt_fun=(lispobj *)(c->cdr); - release_spinlock(&th->interrupt_fun_lock); -} - -#endif - /* 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, * that has the added benefit of automatically discriminating between - * functions and variables. + * functions and variables. */ -void undefined_alien_function() { - funcall0(SymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR)); +void +undefined_alien_function(void) +{ + funcall0(StaticSymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR)); } -boolean handle_guard_page_triggered(os_context_t *context,void *addr){ +/* Called from the REPL, too. */ +void reset_control_stack_guard_page(void) +{ 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 (th->control_stack_guard_page_protected == NIL) { + memset(CONTROL_STACK_GUARD_PAGE(th), 0, os_vm_page_size); + protect_control_stack_guard_page(1, NULL); + protect_control_stack_return_guard_page(0, NULL); + th->control_stack_guard_page_protected = T; + fprintf(stderr, "INFO: Control stack guard page reprotected\n"); + } +} + +boolean +handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr) +{ + struct thread *th=arch_os_get_current_thread(); + + 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(th,0); - protect_control_stack_return_guard_page(th,1); - + if (th->control_stack_guard_page_protected == NIL) + lose("control_stack_guard_page_protected NIL"); + protect_control_stack_guard_page(0, NULL); + protect_control_stack_return_guard_page(1, NULL); + th->control_stack_guard_page_protected = NIL; + fprintf(stderr, "INFO: Control stack guard page unprotected\n"); + +#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) && @@ -885,186 +1535,378 @@ boolean handle_guard_page_triggered(os_context_t *context,void *addr){ * 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(th,1); - protect_control_stack_return_guard_page(th,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 >= 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, StaticSymbolFunction(BINDING_STACK_EXHAUSTED_ERROR)); + return 1; + } + 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; + } + 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 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, SymbolFunction(UNDEFINED_ALIEN_VARIABLE_ERROR)); - return 1; + addr < undefined_alien_address + os_vm_page_size) { + arrange_return_to_lisp_function + (context, StaticSymbolFunction(UNDEFINED_ALIEN_VARIABLE_ERROR)); + return 1; } else return 0; } + +/* + * noise to install handlers + */ -#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 */ +#ifndef LISP_FEATURE_WIN32 +/* 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. + * + * It turns out that NetBSD's SA_NODEFER doesn't DTRT in a different + * way: if SA_NODEFER is set and the signal is in sa_mask, the signal + * will be unblocked in the sigmask during the signal handler. -- RMK + * X-mas day, 2005 + */ +static volatile int sigaction_nodefer_works = -1; -boolean -interrupt_maybe_gc(int signal, siginfo_t *info, void *void_context) +#define SA_NODEFER_TEST_BLOCK_SIGNAL SIGABRT +#define SA_NODEFER_TEST_KILL_SIGNAL SIGUSR1 + +static void +sigaction_nodefer_test_handler(int signal, siginfo_t *info, void *void_context) { - os_context_t *context=(os_context_t *) void_context; - struct thread *th=arch_os_get_current_thread(); - struct interrupt_data *data= - th ? th->interrupt_data : global_interrupt_data; - - if(!data->pending_handler && !foreign_function_call_active && - gc_trigger_hit(signal, info, context)){ - clear_auto_gc_trigger(); - if(!maybe_defer_handler(interrupt_maybe_gc_int, - data,signal,info,void_context)) - interrupt_maybe_gc_int(signal,info,void_context); - return 1; - } - return 0; + sigset_t current; + int i; + 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 + * 2.6.13 or so also doesn't block the other signal when + * SA_NODEFER is set. */ + for(i = 1; i < NSIG; i++) + if (sigismember(¤t, i) != + (((i == SA_NODEFER_TEST_BLOCK_SIGNAL) || (i == signal)) ? 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; } -#endif - -/* this is also used by gencgc, in alloc() */ -boolean -interrupt_maybe_gc_int(int signal, siginfo_t *info, void *void_context) +static void +see_if_sigaction_nodefer_works(void) { - os_context_t *context=(os_context_t *) void_context; + struct sigaction sa, old_sa; - check_blockables_blocked_or_lose(); - fake_foreign_function_call(context); + sa.sa_flags = SA_SIGINFO | SA_NODEFER; + sa.sa_sigaction = sigaction_nodefer_test_handler; + sigemptyset(&sa.sa_mask); + sigaddset(&sa.sa_mask, SA_NODEFER_TEST_BLOCK_SIGNAL); + sigaddset(&sa.sa_mask, SA_NODEFER_TEST_KILL_SIGNAL); + sigaction(SA_NODEFER_TEST_KILL_SIGNAL, &sa, &old_sa); + /* Make sure no signals are blocked. */ + { + sigset_t empty; + sigemptyset(&empty); + thread_sigmask(SIG_SETMASK, &empty, 0); + } + kill(getpid(), SA_NODEFER_TEST_KILL_SIGNAL); + while (sigaction_nodefer_works == -1); + sigaction(SA_NODEFER_TEST_KILL_SIGNAL, &old_sa, NULL); +} - /* 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. - */ +#undef SA_NODEFER_TEST_BLOCK_SIGNAL +#undef SA_NODEFER_TEST_KILL_SIGNAL - /* restore the signal mask from the interrupted context before - * calling into Lisp */ - if (context) - thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); +static void +unblock_me_trampoline(int signal, siginfo_t *info, void *void_context) +{ + SAVE_ERRNO(signal,context,void_context); + sigset_t unblock; - funcall0(SymbolFunction(SUB_GC)); + sigemptyset(&unblock); + sigaddset(&unblock, signal); + thread_sigmask(SIG_UNBLOCK, &unblock, 0); + interrupt_handle_now(signal, info, context); + RESTORE_ERRNO; +} - undo_fake_foreign_function_call(context); - return 1; +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, context); + RESTORE_ERRNO; } - -/* - * noise to install handlers - */ +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; - struct thread *th=arch_os_get_current_thread(); - struct interrupt_data *data= - th ? th->interrupt_data : global_interrupt_data; if (0 > signal || signal >= NSIG) { - lose("bad signal number %d", signal); + lose("bad signal number %d\n", signal); } - if (sigismember(&blockable_sigset,signal)) + if (ARE_SAME_HANDLER(handler, SIG_DFL)) + sa.sa_sigaction = (void (*)(int, siginfo_t*, void*))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; + sa.sa_sigaction = low_level_handle_now_handler; - sigemptyset(&sa.sa_mask); - sigaddset_blockable(&sa.sa_mask); - sa.sa_flags = SA_SIGINFO | SA_RESTART; + 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_INTERRUPT_THREAD - || (signal==SIG_INTERRUPT_THREAD) -#endif - ) - sa.sa_flags|= SA_ONSTACK; + if((signal==SIG_MEMORY_FAULT)) + sa.sa_flags |= SA_ONSTACK; #endif - + sigaction(signal, &sa, NULL); - data->interrupt_low_level_handlers[signal] = - (ARE_SAME_HANDLER(handler, SIG_DFL) ? 0 : handler); + interrupt_low_level_handlers[signal] = + (ARE_SAME_HANDLER(handler, SIG_DFL) ? 0 : handler); } +#endif /* This is called from Lisp. */ unsigned long -install_handler(int signal, void handler(int, siginfo_t*, void*)) +install_handler(int signal, void handler(int, siginfo_t*, os_context_t*)) { +#ifndef LISP_FEATURE_WIN32 struct sigaction sa; - sigset_t old, new; + sigset_t old; union interrupt_handler oldhandler; - struct thread *th=arch_os_get_current_thread(); - struct interrupt_data *data= - th ? th->interrupt_data : global_interrupt_data; FSHOW((stderr, "/entering POSIX install_handler(%d, ..)\n", signal)); - sigemptyset(&new); - sigaddset(&new, signal); - thread_sigmask(SIG_BLOCK, &new, &old); - - sigemptyset(&new); - sigaddset_blockable(&new); - - FSHOW((stderr, "/data->interrupt_low_level_handlers[signal]=%x\n", - (unsigned int)data->interrupt_low_level_handlers[signal])); - if (data->interrupt_low_level_handlers[signal]==0) { - if (ARE_SAME_HANDLER(handler, SIG_DFL) || - ARE_SAME_HANDLER(handler, SIG_IGN)) { - sa.sa_sigaction = handler; - } else if (sigismember(&new, signal)) { - sa.sa_sigaction = maybe_now_maybe_later; - } else { - sa.sa_sigaction = interrupt_handle_now_handler; - } - - sigemptyset(&sa.sa_mask); - sigaddset_blockable(&sa.sa_mask); - sa.sa_flags = SA_SIGINFO | SA_RESTART; - sigaction(signal, &sa, NULL); + 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 = (void (*)(int, siginfo_t*, void*))handler; + else if (sigismember(&deferrable_sigset, signal)) + sa.sa_sigaction = maybe_now_maybe_later; + 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 | + (sigaction_nodefer_works ? SA_NODEFER : 0); + sigaction(signal, &sa, NULL); } - oldhandler = data->interrupt_handlers[signal]; - data->interrupt_handlers[signal].c = handler; + oldhandler = interrupt_handlers[signal]; + interrupt_handlers[signal].c = handler; thread_sigmask(SIG_SETMASK, &old, 0); FSHOW((stderr, "/leaving POSIX install_handler(%d, ..)\n", signal)); return (unsigned long)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) { + lose("SIGABRT received.\n"); +} + +void +interrupt_init(void) +{ +#ifndef LISP_FEATURE_WIN32 int i; SHOW("entering interrupt_init()"); + see_if_sigaction_nodefer_works(); + sigemptyset(&deferrable_sigset); sigemptyset(&blockable_sigset); + sigemptyset(&gc_sigset); + sigaddset_deferrable(&deferrable_sigset); sigaddset_blockable(&blockable_sigset); - - global_interrupt_data=calloc(sizeof(struct interrupt_data), 1); + sigaddset_gc(&gc_sigset); /* Set up high level handler information. */ for (i = 0; i < NSIG; i++) { - global_interrupt_data->interrupt_handlers[i].c = - /* (The cast here blasts away the distinction between - * SA_SIGACTION-style three-argument handlers and - * 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; + interrupt_handlers[i].c = + /* (The cast here blasts away the distinction between + * SA_SIGACTION-style three-argument handlers and + * 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*, os_context_t*))SIG_DFL; } - + undoably_install_low_level_interrupt_handler(SIGABRT, sigabrt_handler); SHOW("returning from interrupt_init()"); +#endif +} + +#ifndef LISP_FEATURE_WIN32 +int +siginfo_code(siginfo_t *info) +{ + return info->si_code; +} +os_vm_address_t current_memory_fault_address; + +void +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 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; + /* 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); + unblock_gc_signals(0, 0); + context_sap = alloc_sap(context); +#ifndef LISP_FEATURE_WIN32 + 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) { + case trap_PendingInterrupt: + FSHOW((stderr, "/\n")); + arch_skip_instruction(context); + interrupt_handle_pending(context); + break; + case trap_Error: + case trap_Cerror: + FSHOW((stderr, "/\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 + case trap_Halt: + fake_foreign_function_call(context); + lose("%%PRIMITIVE HALT called; the party is over.\n"); + default: + unhandled_trap_error(context); + } }