X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Finterrupt.c;h=00c920e8ee1fa53b9d99836a34aa1fdc51ceed7f;hb=0f234877047c56ca945fe54e9e77a9cc2c8141cb;hp=e277dde73f2ae336449e551efa6b067635aa5cac;hpb=ba4659ad35f28a8fefa4a10c3c7012e4ba50d683;p=sbcl.git diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c index e277dde..00c920e 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, @@ -36,19 +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" @@ -56,37 +59,26 @@ #include "globals.h" #include "lispregs.h" #include "validate.h" -#include "monitor.h" #include "gc.h" #include "alloc.h" #include "dynbind.h" #include "interr.h" #include "genesis/fdefn.h" #include "genesis/simple-fun.h" +#include "genesis/cons.h" -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); +static void run_deferred_handler(struct interrupt_data *data, void *v_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); boolean interrupt_maybe_gc_int(int signal, siginfo_t *info, void *v_context); -extern volatile lispobj all_threads_lock; - -/* - * This is a workaround for some slightly silly Linux/GNU Libc - * behaviour: glibc defines sigset_t to support 1024 signals, which is - * more than the kernel. This is usually not a problem, but becomes - * one when we want to save a signal mask from a ucontext, and restore - * it later into another ucontext: the ucontext is allocated on the - * stack by the kernel, so copying a libc-sized sigset_t into it will - * overflow and cause other data on the stack to be corrupted */ - -#define REAL_SIGSET_SIZE_BYTES ((NSIG/8)) - -void sigaddset_blockable(sigset_t *s) +void +sigaddset_deferrable(sigset_t *s) { sigaddset(s, SIGHUP); sigaddset(s, SIGINT); @@ -94,7 +86,6 @@ void sigaddset_blockable(sigset_t *s) sigaddset(s, SIGPIPE); sigaddset(s, SIGALRM); sigaddset(s, SIGURG); - sigaddset(s, SIGFPE); sigaddset(s, SIGTSTP); sigaddset(s, SIGCHLD); sigaddset(s, SIGIO); @@ -103,15 +94,64 @@ void sigaddset_blockable(sigset_t *s) 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); +#endif + #ifdef LISP_FEATURE_SB_THREAD - sigaddset(s, SIG_STOP_FOR_GC); sigaddset(s, SIG_INTERRUPT_THREAD); - sigaddset(s, SIG_THREAD_EXIT); #endif } +void +sigaddset_blockable(sigset_t *s) +{ + 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); +#endif +} + +/* initialized in interrupt_init */ +static sigset_t deferrable_sigset; +static sigset_t blockable_sigset; +#endif + +void +check_blockables_blocked_or_lose() +{ +#if !defined(LISP_FEATURE_WIN32) + /* Get the current sigmask, by blocking the empty set. */ + sigset_t empty,current; + int i; + sigemptyset(&empty); + thread_sigmask(SIG_BLOCK, &empty, ¤t); + for(i = 1; i < NSIG; i++) { + if (sigismember(&blockable_sigset, i) && !sigismember(¤t, i)) + lose("blockable signal %d not blocked\n",i); + } +#endif +} + +inline static void +check_interrupts_enabled_or_lose(os_context_t *context) +{ + struct thread *thread=arch_os_get_current_thread(); + if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) + lose("interrupts not enabled\n"); + if ( +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) + (!foreign_function_call_active) && +#endif + arch_pseudo_atomic_atomic(context)) + lose ("in pseudo atomic section\n"); +} + /* When we catch an internal error, should we pass it back to Lisp to * be handled in a high-level way? (Early in cold init, the answer is * 'no', because Lisp is still too brain-dead to handle anything. @@ -119,69 +159,71 @@ void sigaddset_blockable(sigset_t *s) * becomes 'yes'.) */ boolean internal_errors_enabled = 0; -struct interrupt_data * global_interrupt_data; +#ifndef LISP_FEATURE_WIN32 +static void (*interrupt_low_level_handlers[NSIG]) (int, siginfo_t*, void*); +#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. */ -#if 1 -void reset_signal_mask () +void +reset_signal_mask(void) { +#ifndef LISP_FEATURE_WIN32 sigset_t new; sigemptyset(&new); - sigprocmask(SIG_SETMASK,&new,0); + thread_sigmask(SIG_SETMASK,&new,0); +#endif } -#else -void reset_signal_mask () + +void +block_blockable_signals(void) { - sigset_t new,old; - int i; - int wrong=0; - sigemptyset(&new); - sigprocmask(SIG_SETMASK,&new,&old); - for(i=1; i= 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; @@ -252,18 +302,14 @@ fake_foreign_function_call(os_context_t *context) } /* blocks all blockable signals. If you are calling from a signal handler, - * the usual signal mask will be restored from the context when the handler + * 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. */ - sigset_t block; - sigemptyset(&block); - sigaddset_blockable(&block); - sigprocmask(SIG_BLOCK, &block, 0); + block_blockable_signals(); /* going back into Lisp */ foreign_function_call_active = 0; @@ -274,7 +320,13 @@ 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 } @@ -282,40 +334,40 @@ undo_fake_foreign_function_call(os_context_t *context) * signalling an internal error */ void interrupt_internal_error(int signal, siginfo_t *info, os_context_t *context, - boolean continuable) + boolean continuable) { - lispobj context_sap = 0; + lispobj context_sap; 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); - } + context_sap = alloc_sap(context); - sigprocmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); +#ifndef LISP_FEATURE_WIN32 + thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); +#endif - if (internal_errors_enabled) { - SHOW("in interrupt_internal_error"); + 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); + /* 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"); - } + funcall2(SymbolFunction(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); } void @@ -324,25 +376,73 @@ interrupt_handle_pending(os_context_t *context) struct thread *thread; struct interrupt_data *data; + FSHOW_SIGNAL((stderr, "/entering interrupt_handle_pending\n")); + + check_blockables_blocked_or_lose(); thread=arch_os_get_current_thread(); data=thread->interrupt_data; - /* FIXME I'm not altogether sure this is appropriate if we're - * here as the result of a pseudo-atomic */ - 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 */ + /* 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); - memcpy(os_context_sigmask_addr(context), &data->pending_mask, - REAL_SIGSET_SIZE_BYTES); + if (SymbolValue(GC_INHIBIT,thread)==NIL) { +#ifdef LISP_FEATURE_SB_THREAD + if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL) { + /* another thread has already initiated a gc, this attempt + * might as well be cancelled */ + SetSymbolValue(GC_PENDING,NIL,thread); + SetSymbolValue(STOP_FOR_GC_PENDING,NIL,thread); + sig_stop_for_gc_handler(SIG_STOP_FOR_GC,NULL,context); + } else +#endif + if (SymbolValue(GC_PENDING,thread) != NIL) { + /* GC_PENDING is cleared in SUB-GC, or if another thread + * is doing a gc already we will get a SIG_STOP_FOR_GC and + * that will clear it. */ + interrupt_maybe_gc_int(0,NULL,context); + } + check_blockables_blocked_or_lose(); + } - 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); + /* we may be here only to do the gc stuff, if interrupts are + * enabled run the pending handler */ + if (!((SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) || + ( +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) + (!foreign_function_call_active) && +#endif + arch_pseudo_atomic_atomic(context)))) { + + /* There may be no pending handler, because it was only a gc + * that had to be executed or because pseudo atomic triggered + * twice for a single interrupt. For the interested reader, + * that may happen if an interrupt hits after the interrupted + * flag is cleared but before pseduo-atomic is set and a + * pseudo atomic is interrupted in that interrupt. */ + if (data->pending_handler) { + + /* If we're here as the result of a pseudo-atomic as opposed + * to WITHOUT-INTERRUPTS, then INTERRUPT_PENDING is already + * NIL, because maybe_defer_handler sets + * PSEUDO_ATOMIC_INTERRUPTED only if interrupts are enabled.*/ + SetSymbolValue(INTERRUPT_PENDING, NIL,thread); + +#ifndef LISP_FEATURE_WIN32 + /* restore the saved signal mask from the original signal (the + * one that interrupted us during the critical section) into the + * os_context for the signal we're currently in the handler for. + * This should ensure that when we return from the handler the + * blocked signals are unblocked */ + sigcopyset(os_context_sigmask_addr(context), &data->pending_mask); + + sigemptyset(&data->pending_mask); +#endif + /* This will break on sparc linux: the deferred handler really wants + * to be called with a void_context */ + run_deferred_handler(data,(void *)context); + } + } } /* @@ -364,25 +464,34 @@ void interrupt_handle_now(int signal, siginfo_t *info, void *void_context) { os_context_t *context = (os_context_t*)void_context; - struct thread *thread=arch_os_get_current_thread(); -#ifndef LISP_FEATURE_X86 +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) boolean were_in_lisp; #endif union interrupt_handler handler; -#ifdef LISP_FEATURE_LINUX + check_blockables_blocked_or_lose(); + + +#ifndef LISP_FEATURE_WIN32 + if (sigismember(&deferrable_sigset,signal)) + check_interrupts_enabled_or_lose(context); +#endif + +#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT) /* Under Linux on some architectures, we appear to have to restore the FPU control word from the context, as after the signal is delivered we appear to have a null FPU control word. */ os_restore_fp_control(context); -#endif - handler = thread->interrupt_data->interrupt_handlers[signal]; +#endif + + + handler = interrupt_handlers[signal]; if (ARE_SAME_HANDLER(handler.c, SIG_IGN)) { - return; + return; } - -#ifndef LISP_FEATURE_X86 + +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) were_in_lisp = !foreign_function_call_active; if (were_in_lisp) #endif @@ -390,69 +499,77 @@ 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 */ + * 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 = alloc_sap(context); info_sap = alloc_sap(info); - /* Allow signals again. */ - sigprocmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); - -#ifdef QSHOW_SIGNALS - SHOW("calling Lisp-level handler"); + /* 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 + + 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 { -#ifdef QSHOW_SIGNALS - SHOW("calling C-level handler"); -#endif + FSHOW_SIGNAL((stderr,"/calling C-level handler\n")); +#ifndef LISP_FEATURE_WIN32 /* Allow signals again. */ - sigprocmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); - + thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); +#endif + (*handler.c)(signal, info, void_context); } -#ifndef LISP_FEATURE_X86 +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) 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 @@ -460,127 +577,223 @@ 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 */ - -void +static void run_deferred_handler(struct interrupt_data *data, void *v_context) { - (*(data->pending_handler)) - (data->pending_signal,&(data->pending_info), v_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; + data->pending_handler=0; + (*pending_handler)(data->pending_signal,&(data->pending_info), v_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(); + + if (SymbolValue(INTERRUPT_PENDING,thread) != NIL) + lose("interrupt already pending\n"); + /* 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. + */ if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) { - store_signal_data_for_later(data,handler,signal,info,context); + store_signal_data_for_later(data,handler,signal,info,context); SetSymbolValue(INTERRUPT_PENDING, T,thread); - return 1; - } + FSHOW_SIGNAL((stderr, + "/maybe_defer_handler(%x,%d),thread=%lu: deferred\n", + (unsigned int)handler,signal, + (unsigned long)thread->os_thread)); + 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 ( -#ifndef LISP_FEATURE_X86 - (!foreign_function_call_active) && +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) + /* FIXME: this foreign_function_call_active test is dubious at + * best. If a foreign call is made in a pseudo atomic section + * (?) or more likely a pseudo atomic section is in a foreign + * call then an interrupt is executed immediately. Maybe it + * has to do with C code not maintaining pseudo atomic + * properly. MG - 2005-08-10 */ + (!foreign_function_call_active) && #endif - arch_pseudo_atomic_atomic(context)) { - store_signal_data_for_later(data,handler,signal,info,context); - arch_set_pseudo_atomic_interrupted(context); - return 1; + arch_pseudo_atomic_atomic(context)) { + 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)); + return 1; } + FSHOW_SIGNAL((stderr, + "/maybe_defer_handler(%x,%d),thread=%lu: not deferred\n", + (unsigned int)handler,signal, + (unsigned long)thread->os_thread)); 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", + data->pending_handler, handler); + if (!handler) + lose("tried to defer null interrupt handler\n"); data->pending_handler = handler; data->pending_signal = signal; if(info) - memcpy(&(data->pending_info), info, sizeof(siginfo_t)); + memcpy(&(data->pending_info), info, sizeof(siginfo_t)); + + 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 */ - sigemptyset(&(data->pending_mask)); - memcpy(&(data->pending_mask), - os_context_sigmask_addr(context), - REAL_SIGSET_SIZE_BYTES); - sigaddset_blockable(os_context_sigmask_addr(context)); - } else { - /* this is also called from gencgc alloc(), in which case - * there has been no signal and is therefore no context. */ - sigset_t new; - sigemptyset(&new); - sigaddset_blockable(&new); - sigprocmask(SIG_BLOCK,&new,&(data->pending_mask)); + /* 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 + + struct thread *thread; + struct interrupt_data *data; + + thread=arch_os_get_current_thread(); + data=thread->interrupt_data; + +#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT) os_restore_fp_control(context); -#endif - if(maybe_defer_handler(interrupt_handle_now,data, - signal,info,context)) - return; +#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 */ - sigreturn(void_context); + DARWIN_FIX_CONTEXT(context); +#endif +} + +static void +low_level_interrupt_handle_now(int signal, siginfo_t *info, void *void_context) +{ + os_context_t *context = (os_context_t*)void_context; + +#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT) + os_restore_fp_control(context); +#endif + + check_blockables_blocked_or_lose(); + check_interrupts_enabled_or_lose(context); + interrupt_low_level_handlers[signal](signal, info, void_context); +#ifdef LISP_FEATURE_DARWIN + /* Work around G5 bug */ + DARWIN_FIX_CONTEXT(context); +#endif +} + +static void +low_level_maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context) +{ + os_context_t *context = arch_os_get_context(&void_context); + struct thread *thread; + struct interrupt_data *data; + + thread=arch_os_get_current_thread(); + data=thread->interrupt_data; + +#if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT) + os_restore_fp_control(context); +#endif + + if(maybe_defer_handler(low_level_interrupt_handle_now,data, + signal,info,context)) + return; + low_level_interrupt_handle_now(signal, info, context); +#ifdef LISP_FEATURE_DARWIN + /* Work around G5 bug */ + DARWIN_FIX_CONTEXT(context); #endif } +#endif #ifdef LISP_FEATURE_SB_THREAD + void sig_stop_for_gc_handler(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; sigset_t ss; - int i; - - /* KLUDGE: at least on Linux, the kernel apparently schedules a - thread immediately it is signalled. However, we signal - SIG_STOP_FOR_GC while holding the spinlock, and consequently we - can easily end up with a kind of thundering herd of threads all - wanting to acquire the lock at the same time so that they can - tell the system that they've gone to sleep. So we yield here. - Whether this is the right fix or not is unknown. -- CSR, - 2004-07-16 */ - sched_yield(); - - if(maybe_defer_handler(sig_stop_for_gc_handler,data, - signal,info,context)) { - return; - } - /* need the context stored so it can have registers scavenged */ - fake_foreign_function_call(context); - sigemptyset(&ss); - for(i=1;ios_thread)); + } else { + /* need the context stored so it can have registers scavenged */ + fake_foreign_function_call(context); + + sigfillset(&ss); /* Block everything. */ + thread_sigmask(SIG_BLOCK,&ss,0); - get_spinlock(&all_threads_lock,thread->pid); - thread->state=STATE_STOPPED; - release_spinlock(&all_threads_lock); + if(thread->state!=STATE_RUNNING) { + lose("sig_stop_for_gc_handler: wrong thread state: %ld\n", + fixnum_value(thread->state)); + } + thread->state=STATE_SUSPENDED; + FSHOW_SIGNAL((stderr,"thread=%lu suspended\n",thread->os_thread)); - sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC); - sigwaitinfo(&ss,0); +#if defined(SIG_RESUME_FROM_GC) + sigemptyset(&ss); sigaddset(&ss,SIG_RESUME_FROM_GC); +#else + sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC); +#endif - undo_fake_foreign_function_call(context); + /* 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) { + lose("sig_stop_for_gc_handler: wrong thread state on wakeup: %ld\n", + fixnum_value(thread->state)); + } + + undo_fake_foreign_function_call(context); + } } #endif @@ -590,7 +803,7 @@ 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 - sigreturn(void_context); + DARWIN_FIX_CONTEXT(context); #endif } @@ -598,17 +811,17 @@ interrupt_handle_now_handler(int signal, siginfo_t *info, void *void_context) * stuff to detect and handle hitting the GC trigger */ -#ifndef LISP_FEATURE_GENCGC +#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; + 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)); + void *badaddr=arch_get_bad_addr(signal,info,context); + return (badaddr >= (void *)current_auto_gc_trigger && + badaddr <((void *)current_dynamic_space + dynamic_space_size)); } } #endif @@ -618,123 +831,245 @@ gc_trigger_hit(int signal, siginfo_t *info, os_context_t *context) * previously */ +#if (defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)) +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_X86 +#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? */ #ifdef LISP_FEATURE_X86 /* Suppose the existence of some function that saved all * registers, called call_into_lisp, then restored GP registers and - * returned. We shortcut this: fake the stack that call_into_lisp - * would see, then arrange to have it called directly. post_signal_tramp - * is the second half of this function + * returned. It would look something like this: + + push ebp + mov ebp esp + pushfl + pushal + push $0 + push $0 + pushl {address of function to call} + call 0x8058db0 + addl $12,%esp + popal + popfl + 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 + * signal context so that signal return goes directly to call_into_lisp, + * and when that function (and the lisp function it invoked) returns, + * it returns to the second half of this imaginary function which + * restores all registers and returns to C + + * For this to work, the latter part of the imaginary function + * must obviously exist in reality. That would be post_signal_tramp */ + u32 *sp=(u32 *)*os_context_register_addr(context,reg_ESP); - *(sp-14) = post_signal_tramp; /* return address for call_into_lisp */ - *(sp-13) = function; /* args for call_into_lisp : function*/ - *(sp-12) = 0; /* arg array */ - *(sp-11) = 0; /* no. args */ +#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) = call_into_lisp_tramp; + *os_context_register_addr(context,reg_ECX) = 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 */ /* this order matches that used in POPAD */ - *(sp-10)=*os_context_register_addr(context,reg_EDI); - *(sp-9)=*os_context_register_addr(context,reg_ESI); - /* this gets overwritten again before it's used, anyway */ - *(sp-8)=*os_context_register_addr(context,reg_EBP); - *(sp-7)=0 ; /* POPAD doesn't set ESP, but expects a gap for it anyway */ - *(sp-6)=*os_context_register_addr(context,reg_EBX); - - *(sp-5)=*os_context_register_addr(context,reg_EDX); - *(sp-4)=*os_context_register_addr(context,reg_ECX); - *(sp-3)=*os_context_register_addr(context,reg_EAX); + *(sp-11)=*os_context_register_addr(context,reg_EDI); + *(sp-10)=*os_context_register_addr(context,reg_ESI); + + *(sp-9)=*os_context_register_addr(context,reg_ESP)-8; + /* POPAD ignores the value of ESP: */ + *(sp-8)=0; + *(sp-7)=*os_context_register_addr(context,reg_EBX); + + *(sp-6)=*os_context_register_addr(context,reg_EDX); + *(sp-5)=*os_context_register_addr(context,reg_ECX); + *(sp-4)=*os_context_register_addr(context,reg_EAX); + *(sp-3)=*context_eflags_addr(context); *(sp-2)=*os_context_register_addr(context,reg_EBP); *(sp-1)=*os_context_pc_addr(context); -#else +#endif + +#elif defined(LISP_FEATURE_X86_64) + u64 *sp=(u64 *)*os_context_register_addr(context,reg_RSP); + + /* 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); + *(sp-15)=*os_context_register_addr(context,reg_R13); + *(sp-14)=*os_context_register_addr(context,reg_R12); + *(sp-13)=*os_context_register_addr(context,reg_R11); + *(sp-12)=*os_context_register_addr(context,reg_R10); + *(sp-11)=*os_context_register_addr(context,reg_R9); + *(sp-10)=*os_context_register_addr(context,reg_R8); + *(sp-9)=*os_context_register_addr(context,reg_RDI); + *(sp-8)=*os_context_register_addr(context,reg_RSI); + /* skip RBP and RSP */ + *(sp-7)=*os_context_register_addr(context,reg_RBX); + *(sp-6)=*os_context_register_addr(context,reg_RDX); + *(sp-5)=*os_context_register_addr(context,reg_RCX); + *(sp-4)=*os_context_register_addr(context,reg_RAX); + *(sp-3)=*context_eflags_addr(context); + *(sp-2)=*os_context_register_addr(context,reg_RBP); + *(sp-1)=*os_context_pc_addr(context); + + *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 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; - *os_context_register_addr(context,reg_ESP) = sp-14; + +#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) = (os_context_register_t)(sp-15); +#endif /* __NETBSD__ */ +#endif /* LISP_FEATURE_DARWIN */ + +#elif defined(LISP_FEATURE_X86_64) + *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp; + *os_context_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 } #ifdef LISP_FEATURE_SB_THREAD -void interrupt_thread_handler(int num, siginfo_t *info, void *v_context) + +/* 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); - struct thread *th=arch_os_get_current_thread(); - struct interrupt_data *data= - th ? th->interrupt_data : global_interrupt_data; - if(maybe_defer_handler(interrupt_thread_handler,data,num,info,context)){ - return ; - } - arrange_return_to_lisp_function(context,info->si_value.sival_int); -} -void thread_exit_handler(int num, siginfo_t *info, void *v_context) -{ /* called when a child thread exits */ - os_context_t *context = (os_context_t*)arch_os_get_context(&v_context); - struct thread *th=arch_os_get_current_thread(); - pid_t kid; - int *status; - struct interrupt_data *data= - th ? th->interrupt_data : global_interrupt_data; - if(maybe_defer_handler(thread_exit_handler,data,num,info,context)){ - return ; - } - while(1) { - kid=waitpid(-1,&status,__WALL|WNOHANG); - if(kid<1) break; - if(WIFEXITED(status) || WIFSIGNALED(status)) { - struct thread *th=find_thread_by_pid(kid); - if(!th) continue; - funcall1(SymbolFunction(HANDLE_THREAD_EXIT),make_fixnum(kid)); - destroy_thread(th); - } - } + /* 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 -boolean handle_control_stack_guard_triggered(os_context_t *context,void *addr){ +/* 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. + */ +void +undefined_alien_function() { + funcall0(SymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR)); +} + +boolean +handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr) +{ struct thread *th=arch_os_get_current_thread(); - /* note the os_context hackery here. When the signal handler returns, + + /* note the os_context hackery here. When the signal handler returns, * it won't go back to what it was doing ... */ - if(addr>=(void *)CONTROL_STACK_GUARD_PAGE(th) && - addr<(void *)(CONTROL_STACK_GUARD_PAGE(th)+os_vm_page_size)) { - /* we hit the end of the control stack. disable protection - * temporarily so the error handler has some headroom */ - protect_control_stack_guard_page(th->pid,0L); - - arrange_return_to_lisp_function - (context, SymbolFunction(CONTROL_STACK_EXHAUSTED_ERROR)); - return 1; + if(addr >= CONTROL_STACK_GUARD_PAGE(th) && + addr < CONTROL_STACK_GUARD_PAGE(th) + os_vm_page_size) { + /* We hit the end of the control stack: disable guard page + * protection so the error handler has some headroom, protect the + * previous page so that we can catch returns from the guard page + * and restore it. */ + protect_control_stack_guard_page(0); + protect_control_stack_return_guard_page(1); + + arrange_return_to_lisp_function + (context, SymbolFunction(CONTROL_STACK_EXHAUSTED_ERROR)); + return 1; + } + else if(addr >= CONTROL_STACK_RETURN_GUARD_PAGE(th) && + addr < CONTROL_STACK_RETURN_GUARD_PAGE(th) + os_vm_page_size) { + /* We're returning from the guard page: reprotect it, and + * 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); + 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; } else return 0; } @@ -750,16 +1085,28 @@ boolean interrupt_maybe_gc(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(!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; + struct thread *thread=arch_os_get_current_thread(); + clear_auto_gc_trigger(); + /* Don't flood the system with interrupts if the need to gc is + * already noted. This can happen for example when SUB-GC + * allocates or after a gc triggered in a WITHOUT-GCING. */ + if (SymbolValue(GC_PENDING,thread) == NIL) { + if (SymbolValue(GC_INHIBIT,thread) == NIL) { + if (arch_pseudo_atomic_atomic(context)) { + /* set things up so that GC happens when we finish + * the PA section */ + SetSymbolValue(GC_PENDING,T,thread); + arch_set_pseudo_atomic_interrupted(context); + } else { + interrupt_maybe_gc_int(signal,info,void_context); + } + } else { + SetSymbolValue(GC_PENDING,T,thread); + } + } + return 1; } return 0; } @@ -770,19 +1117,52 @@ interrupt_maybe_gc(int signal, siginfo_t *info, void *void_context) boolean interrupt_maybe_gc_int(int signal, siginfo_t *info, void *void_context) { - sigset_t new; os_context_t *context=(os_context_t *) void_context; +#ifndef LISP_FEATURE_WIN32 + struct thread *thread=arch_os_get_current_thread(); +#endif + fake_foreign_function_call(context); + /* SUB-GC may return without GCing if *GC-INHIBIT* is set, in * which case we will be running with no gc trigger barrier * thing for a while. But it shouldn't be long until the end - * of WITHOUT-GCING. */ + * of WITHOUT-GCING. + * + * FIXME: It would be good to protect the end of dynamic space + * and signal a storage condition from there. + */ - sigemptyset(&new); - sigaddset_blockable(&new); - /* enable signals before calling into Lisp */ - sigprocmask(SIG_UNBLOCK,&new,0); + /* Restore the signal mask from the interrupted context before + * calling into Lisp if interrupts are enabled. Why not always? + * + * Suppose there is a WITHOUT-INTERRUPTS block far, far out. If an + * interrupt hits while in SUB-GC, it is deferred and the + * os_context_sigmask of that interrupt is set to block further + * deferrable interrupts (until the first one is + * handled). Unfortunately, that context refers to this place and + * when we return from here the signals will not be blocked. + * + * A kludgy alternative is to propagate the sigmask change to the + * outer context. + */ +#ifndef LISP_FEATURE_WIN32 + if(SymbolValue(INTERRUPTS_ENABLED,thread)!=NIL) + thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0); +#ifdef LISP_FEATURE_SB_THREAD + else { + sigset_t new; + sigemptyset(&new); +#if defined(SIG_RESUME_FROM_GC) + sigaddset(&new,SIG_RESUME_FROM_GC); +#endif + sigaddset(&new,SIG_STOP_FOR_GC); + thread_sigmask(SIG_UNBLOCK,&new,0); + } +#endif +#endif funcall0(SymbolFunction(SUB_GC)); + undo_fake_foreign_function_call(context); return 1; } @@ -792,104 +1172,236 @@ interrupt_maybe_gc_int(int signal, siginfo_t *info, void *void_context) * noise to install handlers */ +#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; + +#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) +{ + sigset_t empty, current; + int i; + sigemptyset(&empty); + thread_sigmask(SIG_BLOCK, &empty, ¤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; +} + +static void +see_if_sigaction_nodefer_works() +{ + struct sigaction sa, old_sa; + + sa.sa_flags = SA_SIGINFO | SA_NODEFER; + sa.sa_sigaction = sigaction_nodefer_test_handler; + sigemptyset(&sa.sa_mask); + sigaddset(&sa.sa_mask, 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); +} + +#undef SA_NODEFER_TEST_BLOCK_SIGNAL +#undef SA_NODEFER_TEST_KILL_SIGNAL + +static void +unblock_me_trampoline(int signal, siginfo_t *info, void *void_context) +{ + sigset_t unblock; + + sigemptyset(&unblock); + sigaddset(&unblock, signal); + thread_sigmask(SIG_UNBLOCK, &unblock, 0); + interrupt_handle_now_handler(signal, info, void_context); +} + +static void +low_level_unblock_me_trampoline(int signal, siginfo_t *info, void *void_context) +{ + sigset_t unblock; + + sigemptyset(&unblock); + sigaddset(&unblock, signal); + thread_sigmask(SIG_UNBLOCK, &unblock, 0); + (*interrupt_low_level_handlers[signal])(signal, info, void_context); +} + void undoably_install_low_level_interrupt_handler (int signal, - void handler(int, - siginfo_t*, - void*)) + void handler(int, + siginfo_t*, + void*)) { 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); } - sa.sa_sigaction = handler; - sigemptyset(&sa.sa_mask); - sigaddset_blockable(&sa.sa_mask); - sa.sa_flags = SA_SIGINFO | SA_RESTART; + if (ARE_SAME_HANDLER(handler, SIG_DFL)) + sa.sa_sigaction = handler; + else if (sigismember(&deferrable_sigset,signal)) + sa.sa_sigaction = low_level_maybe_now_maybe_later; + /* 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; + + 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) + if((signal==SIG_MEMORY_FAULT) +#ifdef SIG_MEMORY_FAULT2 + || (signal==SIG_MEMORY_FAULT2) +#endif #ifdef SIG_INTERRUPT_THREAD || (signal==SIG_INTERRUPT_THREAD) #endif ) - sa.sa_flags|= SA_ONSTACK; + 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*)) { +#ifndef LISP_FEATURE_WIN32 struct sigaction sa; sigset_t old, new; 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); - sigprocmask(SIG_BLOCK, &new, &old); - - sigemptyset(&new); - sigaddset_blockable(&new); - - FSHOW((stderr, "/data->interrupt_low_level_handlers[signal]=%d\n", - 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); + thread_sigmask(SIG_BLOCK, &new, &old); + + FSHOW((stderr, "/interrupt_low_level_handlers[signal]=%x\n", + (unsigned int)interrupt_low_level_handlers[signal])); + if (interrupt_low_level_handlers[signal]==0) { + if (ARE_SAME_HANDLER(handler, SIG_DFL) || + ARE_SAME_HANDLER(handler, SIG_IGN)) + sa.sa_sigaction = handler; + 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; - sigprocmask(SIG_SETMASK, &old, 0); + 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 } void interrupt_init() { +#ifndef LISP_FEATURE_WIN32 int i; SHOW("entering interrupt_init()"); - global_interrupt_data=calloc(sizeof(struct interrupt_data), 1); + see_if_sigaction_nodefer_works(); + sigemptyset(&deferrable_sigset); + sigemptyset(&blockable_sigset); + sigaddset_deferrable(&deferrable_sigset); + sigaddset_blockable(&blockable_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*, void*))SIG_DFL; } 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 the information. + * However, since this is mostly informative, we'll live with that for + * now -- some address is better then no address in this case. + */ + current_memory_fault_address = addr; + arrange_return_to_lisp_function(context, SymbolFunction(MEMORY_FAULT_ERROR)); +} +#endif