X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Finterrupt.c;h=b6c5c0dbf4695ed7052710500f4c1d779c6cf13c;hb=1b32a547d26cf078ba9f2948edeb27ff91e78f49;hp=eed61e06086fbf753303bb478d12b449ee83a19f;hpb=eab519f164be2b266ee7349fa2d2ad81f25907ae;p=sbcl.git diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c index eed61e0..b6c5c0d 100644 --- a/src/runtime/interrupt.c +++ b/src/runtime/interrupt.c @@ -63,22 +63,75 @@ #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" -static void run_deferred_handler(struct interrupt_data *data, void *v_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. */ +#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 + +/* 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(context,void_context) \ + { \ + int _saved_errno = errno; \ + RESTORE_FP_CONTROL_WORD(context,void_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); +static void +fill_current_sigmask(sigset_t *sigset) +{ + /* Get the current sigmask, by blocking the empty set. */ + sigset_t empty; + sigemptyset(&empty); + thread_sigmask(SIG_BLOCK, &empty, sigset); +} + void sigaddset_deferrable(sigset_t *s) { sigaddset(s, SIGHUP); sigaddset(s, SIGINT); + sigaddset(s, SIGTERM); sigaddset(s, SIGQUIT); sigaddset(s, SIGPIPE); sigaddset(s, SIGALRM); @@ -86,48 +139,129 @@ sigaddset_deferrable(sigset_t *s) 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 +sigdelset_deferrable(sigset_t *s) +{ + sigdelset(s, SIGHUP); + sigdelset(s, SIGINT); + sigdelset(s, SIGQUIT); + sigdelset(s, SIGPIPE); + sigdelset(s, SIGALRM); + sigdelset(s, SIGURG); + sigdelset(s, SIGTSTP); + sigdelset(s, SIGCHLD); + sigdelset(s, SIGIO); +#ifndef LISP_FEATURE_HPUX + sigdelset(s, SIGXCPU); + sigdelset(s, SIGXFSZ); #endif + sigdelset(s, SIGVTALRM); + sigdelset(s, SIGPROF); + sigdelset(s, SIGWINCH); +} +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_INTERRUPT_THREAD); + sigaddset(sigset,SIG_STOP_FOR_GC); #endif } void -sigaddset_blockable(sigset_t *s) +sigdelset_gc(sigset_t *sigset) { - sigaddset_deferrable(s); #ifdef LISP_FEATURE_SB_THREAD -#ifdef SIG_RESUME_FROM_GC - sigaddset(s, SIG_RESUME_FROM_GC); -#endif - sigaddset(s, SIG_STOP_FOR_GC); + sigdelset(sigset,SIG_STOP_FOR_GC); #endif } /* initialized in interrupt_init */ -static sigset_t deferrable_sigset; -static sigset_t blockable_sigset; +sigset_t deferrable_sigset; +sigset_t blockable_sigset; +sigset_t gc_sigset; #endif +boolean +deferrables_blocked_in_sigset_p(sigset_t *sigset) +{ +#if !defined(LISP_FEATURE_WIN32) + int i; + for(i = 1; i < NSIG; i++) { + if (sigismember(&deferrable_sigset, i) && sigismember(sigset, i)) + return 1; + } +#endif + return 0; +} + +void +check_deferrables_unblocked_in_sigset_or_lose(sigset_t *sigset) +{ +#if !defined(LISP_FEATURE_WIN32) + int i; + for(i = 1; i < NSIG; i++) { + if (sigismember(&deferrable_sigset, i) && sigismember(sigset, i)) + lose("deferrable signal %d blocked\n",i); + } +#endif +} + +void +check_deferrables_blocked_in_sigset_or_lose(sigset_t *sigset) +{ +#if !defined(LISP_FEATURE_WIN32) + int i; + for(i = 1; i < NSIG; i++) { + if (sigismember(&deferrable_sigset, i) && !sigismember(sigset, i)) + lose("deferrable signal %d not blocked\n",i); + } +#endif +} + +void +check_deferrables_unblocked_or_lose(void) +{ +#if !defined(LISP_FEATURE_WIN32) + sigset_t current; + fill_current_sigmask(¤t); + check_deferrables_unblocked_in_sigset_or_lose(¤t); +#endif +} + +void +check_deferrables_blocked_or_lose(void) +{ +#if !defined(LISP_FEATURE_WIN32) + sigset_t current; + fill_current_sigmask(¤t); + check_deferrables_blocked_in_sigset_or_lose(¤t); +#endif +} + void check_blockables_blocked_or_lose(void) { #if !defined(LISP_FEATURE_WIN32) - /* Get the current sigmask, by blocking the empty set. */ - sigset_t empty,current; + sigset_t current; int i; - sigemptyset(&empty); - thread_sigmask(SIG_BLOCK, &empty, ¤t); + fill_current_sigmask(¤t); for(i = 1; i < NSIG; i++) { if (sigismember(&blockable_sigset, i) && !sigismember(¤t, i)) lose("blockable signal %d not blocked\n",i); @@ -136,16 +270,24 @@ check_blockables_blocked_or_lose(void) } void -unblock_gc_signals(void) +check_gc_signals_unblocked_in_sigset_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) + int i; + for(i = 1; i < NSIG; i++) { + if (sigismember(&gc_sigset, i) && sigismember(sigset, i)) + lose("gc signal %d blocked\n",i); + } #endif - sigaddset(&new,SIG_STOP_FOR_GC); - thread_sigmask(SIG_UNBLOCK,&new,0); +} + +void +check_gc_signals_unblocked_or_lose(void) +{ +#if !defined(LISP_FEATURE_WIN32) + sigset_t current; + fill_current_sigmask(¤t); + check_gc_signals_unblocked_in_sigset_or_lose(¤t); #endif } @@ -159,6 +301,122 @@ check_interrupts_enabled_or_lose(os_context_t *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.*/ +void +maybe_save_gc_mask_and_block_deferrables(sigset_t *sigset) +{ +#ifndef LISP_FEATURE_WIN32 + 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. */ + thread_sigmask(SIG_BLOCK, &blockable_sigset, &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); + unblock_gc_signals(); + 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"); + } +#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_in_sigset_or_lose(sigset); + if (interrupt_pending || interrupt_deferred_p) + check_deferrables_blocked_in_sigset_or_lose(sigset); + else { + check_deferrables_unblocked_in_sigset_or_lose(sigset); + /* If deferrables are unblocked then we are open to signals + * that run lisp code. */ + check_gc_signals_unblocked_in_sigset_or_lose(sigset); + } +#endif +} + /* 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. @@ -167,37 +425,78 @@ check_interrupts_enabled_or_lose(os_context_t *context) boolean internal_errors_enabled = 0; #ifndef LISP_FEATURE_WIN32 -static void (*interrupt_low_level_handlers[NSIG]) (int, siginfo_t*, void*); +static +void (*interrupt_low_level_handlers[NSIG]) (int, siginfo_t*, os_context_t*); #endif union interrupt_handler interrupt_handlers[NSIG]; -/* 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 +block_blockable_signals(void) +{ +#ifndef LISP_FEATURE_WIN32 + thread_sigmask(SIG_BLOCK, &blockable_sigset, 0); +#endif +} void -reset_signal_mask(void) +block_deferrable_signals(void) { #ifndef LISP_FEATURE_WIN32 - sigset_t new; - sigemptyset(&new); - thread_sigmask(SIG_SETMASK,&new,0); + thread_sigmask(SIG_BLOCK, &deferrable_sigset, 0); #endif } void -block_blockable_signals(void) +unblock_deferrable_signals_in_sigset(sigset_t *sigset) { #ifndef LISP_FEATURE_WIN32 - thread_sigmask(SIG_BLOCK, &blockable_sigset, 0); + if (interrupt_handler_pending_p()) + lose("unblock_deferrable_signals_in_sigset: losing proposition\n"); + check_gc_signals_unblocked_in_sigset_or_lose(sigset); + sigdelset_deferrable(sigset); #endif } void -block_deferrable_signals(void) +unblock_deferrable_signals(void) { #ifndef LISP_FEATURE_WIN32 - thread_sigmask(SIG_BLOCK, &deferrable_sigset, 0); + if (interrupt_handler_pending_p()) + lose("unblock_deferrable_signals: losing proposition\n"); + check_gc_signals_unblocked_or_lose(); + thread_sigmask(SIG_UNBLOCK, &deferrable_sigset, 0); +#endif +} + +void +unblock_gc_signals(void) +{ +#if defined(LISP_FEATURE_SB_THREAD) && !defined(LISP_FEATURE_WIN32) + thread_sigmask(SIG_UNBLOCK,&gc_sigset,0); +#endif +} + +void +unblock_signals_in_context_and_maybe_warn(os_context_t *context) +{ +#ifndef LISP_FEATURE_WIN32 + int i, oops=0; + sigset_t *sigset=os_context_sigmask_addr(context); + for(i = 1; i < NSIG; i++) { + if (sigismember(&gc_sigset, i) && sigismember(sigset, i)) { + if (!oops) { + fprintf(stderr, +"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"); + } + oops=1; + } + } + sigdelset_gc(sigset); + if (!interrupt_handler_pending_p()) { + unblock_deferrable_signals_in_sigset(sigset); + } #endif } @@ -275,12 +574,19 @@ fake_foreign_function_call(os_context_t *context) dynamic_space_free_pointer = (lispobj *)(unsigned long) (*os_context_register_addr(context, reg_ALLOC)); - /* fprintf(stderr,"dynamic_space_free_pointer: %p\n", dynamic_space_free_pointer); */ +/* 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\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 = @@ -333,7 +639,8 @@ undo_fake_foreign_function_call(os_context_t *context) | (*os_context_register_addr(context, reg_ALLOC) & LOWTAG_MASK); /* - ((unsigned long)(*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 @@ -357,12 +664,23 @@ interrupt_internal_error(os_context_t *context, boolean continuable) /* Allocate the SAP object while the interrupts are still * disabled. */ + unblock_gc_signals(); context_sap = alloc_sap(context); #ifndef LISP_FEATURE_WIN32 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 /* Display some rudimentary debugging information about the @@ -370,7 +688,7 @@ interrupt_internal_error(os_context_t *context, boolean continuable) * 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 */ @@ -378,110 +696,161 @@ interrupt_internal_error(os_context_t *context, boolean 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) { - /* There are three ways we can get here. First, if an interrupt + /* 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 + * 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, 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. */ + * *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; + struct thread *thread = arch_os_get_current_thread(); + struct interrupt_data *data = thread->interrupt_data; - /* Punt if in PA section, marking it as interrupted. This can - * happenat least if we pick up a GC request while in a - * WITHOUT-GCING with an outer PA -- it is not immediately clear - * to me that this should/could ever happen, but better safe then - * sorry. --NS 2007-05-15 */ if (arch_pseudo_atomic_atomic(context)) { - arch_set_pseudo_atomic_interrupted(context); - return; + lose("Handling pending interrupt in pseduo atomic."); } - thread = arch_os_get_current_thread(); - FSHOW_SIGNAL((stderr, "/entering interrupt_handle_pending\n")); check_blockables_blocked_or_lose(); - /* 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); + /* 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; + } 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 - 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. */ - maybe_gc(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(); + + /* 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 - /* we may be here only to do the gc stuff, if interrupts are - * enabled run the pending handler */ - if (SymbolValue(INTERRUPTS_ENABLED,thread) != NIL) { - struct interrupt_data *data = thread->interrupt_data; - - /* 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 pseudo-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); - - /* 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); - /* 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); } + /* 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")); #endif } -/* - * 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, os_context_t *context) @@ -498,13 +867,6 @@ interrupt_handle_now(int signal, siginfo_t *info, os_context_t *context) 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)) { @@ -546,21 +908,12 @@ interrupt_handle_now(int signal, siginfo_t *info, os_context_t *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; /* 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); - } -#endif + unblock_gc_signals(); + context_sap = alloc_sap(context); + info_sap = alloc_sap(info); FSHOW_SIGNAL((stderr,"/calling Lisp-level handler\n")); @@ -569,6 +922,7 @@ interrupt_handle_now(int signal, siginfo_t *info, os_context_t *context) info_sap, context_sap); } else { + /* This cannot happen in sane circumstances. */ FSHOW_SIGNAL((stderr,"/calling C-level handler\n")); @@ -597,16 +951,18 @@ interrupt_handle_now(int signal, siginfo_t *info, os_context_t *context) * 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 @@ -620,17 +976,28 @@ maybe_defer_handler(void *handler, struct interrupt_data *data, 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) { + if ((SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) || + in_leaving_without_gcing_race_p(thread)) { store_signal_data_for_later(data,handler,signal,info,context); SetSymbolValue(INTERRUPT_PENDING, T,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))); + check_interrupt_context_or_lose(context); return 1; } /* a slightly confusing test. arch_pseudo_atomic_atomic() doesn't @@ -640,15 +1007,14 @@ maybe_defer_handler(void *handler, struct interrupt_data *data, 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)); + "/maybe_defer_handler(%x,%d): deferred(PA)\n", + (unsigned int)handler,signal)); + 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; } @@ -667,94 +1033,84 @@ store_signal_data_for_later (struct interrupt_data *data, void *handler, 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); + SAVE_ERRNO(context,void_context); struct thread *thread = arch_os_get_current_thread(); struct interrupt_data *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)) interrupt_handle_now(signal, info, context); - -#ifdef LISP_FEATURE_DARWIN - DARWIN_FIX_CONTEXT(context); -#endif + RESTORE_ERRNO; } static void -low_level_interrupt_handle_now(int signal, siginfo_t *info, os_context_t *context) +low_level_interrupt_handle_now(int signal, siginfo_t *info, + os_context_t *context) { /* No FP control fixage needed, caller has done that. */ check_blockables_blocked_or_lose(); check_interrupts_enabled_or_lose(context); - interrupt_low_level_handlers[signal](signal, info, context); + (*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); + SAVE_ERRNO(context,void_context); struct thread *thread = arch_os_get_current_thread(); struct interrupt_data *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)) low_level_interrupt_handle_now(signal, info, context); - -#ifdef LISP_FEATURE_DARWIN - DARWIN_FIX_CONTEXT(context); -#endif + 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; - if (arch_pseudo_atomic_atomic(context)) { + /* 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) { SetSymbolValue(STOP_FOR_GC_PENDING,T,thread); - arch_set_pseudo_atomic_interrupted(context); - FSHOW_SIGNAL((stderr,"thread=%lu sig_stop_for_gc deferred (PA)\n", - thread->os_thread)); + FSHOW_SIGNAL((stderr, "sig_stop_for_gc deferred (*GC-INHIBIT*)\n")); return; - } - else if (SymbolValue(GC_INHIBIT,thread) != NIL) { + } else if (arch_pseudo_atomic_atomic(context)) { SetSymbolValue(STOP_FOR_GC_PENDING,T,thread); - FSHOW_SIGNAL((stderr, - "thread=%lu sig_stop_for_gc deferred (*GC-INHIBIT*)\n", - thread->os_thread)); + arch_set_pseudo_atomic_interrupted(context); + maybe_save_gc_mask_and_block_deferrables + (os_context_sigmask_addr(context)); + FSHOW_SIGNAL((stderr,"sig_stop_for_gc deferred (PA)\n")); 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 */ @@ -768,54 +1124,41 @@ sig_stop_for_gc_handler(int signal, siginfo_t *info, void *void_context) SetSymbolValue(GC_PENDING,NIL,thread); SetSymbolValue(STOP_FOR_GC_PENDING,NIL,thread); - 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; - FSHOW_SIGNAL((stderr,"thread=%lu suspended\n",thread->os_thread)); + set_thread_state(thread,STATE_SUSPENDED); + FSHOW_SIGNAL((stderr,"suspended\n")); - sigemptyset(&ss); -#if defined(SIG_RESUME_FROM_GC) - sigaddset(&ss,SIG_RESUME_FROM_GC); -#else - sigaddset(&ss,SIG_STOP_FOR_GC); -#endif + wait_for_thread_state_change(thread, STATE_SUSPENDED); + FSHOW_SIGNAL((stderr,"resumed\n")); - /* 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 - - FSHOW_SIGNAL((stderr,"thread=%lu resumed\n",thread->os_thread)); - if(thread->state!=STATE_RUNNING) { + 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))); } 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); -#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT) - os_restore_fp_control(context); + SAVE_ERRNO(context,void_context); +#ifndef LISP_FEATURE_WIN32 + if ((signal == SIGILL) || (signal == SIGBUS) +#ifndef LISP_FEATURE_LINUX + || (signal == SIGEMT) #endif - interrupt_handle_now(signal, info, context); -#ifdef LISP_FEATURE_DARWIN - DARWIN_FIX_CONTEXT(context); + ) + 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 @@ -833,6 +1176,10 @@ 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_in_sigset_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); @@ -841,8 +1188,14 @@ arrange_return_to_lisp_function(os_context_t *context, lispobj function) /* 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 @@ -1000,24 +1353,10 @@ arrange_return_to_lisp_function(os_context_t *context, lispobj function) *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) -{ - 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)); -} - -#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, @@ -1027,7 +1366,7 @@ interrupt_thread_handler(int num, siginfo_t *info, void *v_context) void undefined_alien_function(void) { - funcall0(SymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR)); + funcall0(StaticSymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR)); } boolean @@ -1043,11 +1382,17 @@ handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr) * 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); + corruption_warning_and_maybe_lose("Control stack exhausted"); + protect_control_stack_guard_page(0, NULL); + protect_control_stack_return_guard_page(1, NULL); +#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) && @@ -1056,14 +1401,55 @@ handle_guard_page_triggered(os_context_t *context,os_vm_address_t 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(1); - protect_control_stack_return_guard_page(0); + fprintf(stderr, "INFO: Control stack guard page reprotected\n"); + protect_control_stack_guard_page(1, NULL); + protect_control_stack_return_guard_page(0, NULL); + return 1; + } + else if(addr >= BINDING_STACK_GUARD_PAGE(th) && + addr < BINDING_STACK_GUARD_PAGE(th) + os_vm_page_size) { + corruption_warning_and_maybe_lose("Binding stack exhausted"); + protect_binding_stack_guard_page(0, NULL); + protect_binding_stack_return_guard_page(1, NULL); + + /* 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) { + fprintf(stderr, "INFO: Binding stack guard page reprotected\n"); + protect_binding_stack_guard_page(1, NULL); + protect_binding_stack_return_guard_page(0, NULL); + return 1; + } + else if(addr >= ALIEN_STACK_GUARD_PAGE(th) && + addr < ALIEN_STACK_GUARD_PAGE(th) + os_vm_page_size) { + corruption_warning_and_maybe_lose("Alien stack exhausted"); + protect_alien_stack_guard_page(0, NULL); + protect_alien_stack_return_guard_page(1, NULL); + + /* 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) { + fprintf(stderr, "INFO: Alien stack guard page reprotected\n"); + protect_alien_stack_guard_page(1, NULL); + protect_alien_stack_return_guard_page(0, NULL); 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)); + (context, StaticSymbolFunction(UNDEFINED_ALIEN_VARIABLE_ERROR)); return 1; } else return 0; @@ -1142,23 +1528,35 @@ see_if_sigaction_nodefer_works(void) static void unblock_me_trampoline(int signal, siginfo_t *info, void *void_context) { + SAVE_ERRNO(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(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(context,void_context); + (*interrupt_low_level_handlers[signal])(signal, info, context); + RESTORE_ERRNO; } void @@ -1172,30 +1570,20 @@ undoably_install_low_level_interrupt_handler (int signal, } 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; 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 - ) + if((signal==SIG_MEMORY_FAULT)) sa.sa_flags |= SA_ONSTACK; #endif @@ -1207,7 +1595,7 @@ undoably_install_low_level_interrupt_handler (int signal, /* 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; @@ -1225,7 +1613,7 @@ install_handler(int signal, void handler(int, siginfo_t*, void*)) 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; else if (sigismember(&deferrable_sigset, signal)) sa.sa_sigaction = maybe_now_maybe_later; else if (!sigaction_nodefer_works && @@ -1254,6 +1642,14 @@ install_handler(int signal, void handler(int, siginfo_t*, void*)) #endif } +/* This must not go through lisp as it's allowed anytime, even when on + * the altstack. */ +void +sigabrt_handler(int signal, siginfo_t *info, os_context_t *context) +{ + lose("SIGABRT received.\n"); +} + void interrupt_init(void) { @@ -1263,8 +1659,10 @@ interrupt_init(void) see_if_sigaction_nodefer_works(); sigemptyset(&deferrable_sigset); sigemptyset(&blockable_sigset); + sigemptyset(&gc_sigset); sigaddset_deferrable(&deferrable_sigset); sigaddset_blockable(&blockable_sigset); + sigaddset_gc(&gc_sigset); /* Set up high level handler information. */ for (i = 0; i < NSIG; i++) { @@ -1274,9 +1672,9 @@ interrupt_init(void) * 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; } - + undoably_install_low_level_interrupt_handler(SIGABRT, sigabrt_handler); SHOW("returning from interrupt_init()"); #endif } @@ -1298,7 +1696,15 @@ lisp_memory_fault_error(os_context_t *context, os_vm_address_t addr) * 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", addr); + 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 @@ -1307,11 +1713,12 @@ unhandled_trap_error(os_context_t *context) { lispobj context_sap; fake_foreign_function_call(context); + unblock_gc_signals(); context_sap = alloc_sap(context); #ifndef LISP_FEATURE_WIN32 thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); #endif - funcall1(SymbolFunction(UNHANDLED_TRAP_ERROR), context_sap); + funcall1(StaticSymbolFunction(UNHANDLED_TRAP_ERROR), context_sap); lose("UNHANDLED-TRAP-ERROR fell through"); } @@ -1356,4 +1763,3 @@ handle_trap(os_context_t *context, int trap) unhandled_trap_error(context); } } -