X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Finterrupt.c;h=65f50bf41ab6f4aec771c2eba4ff62d811a90124;hb=079ef9dad558ca07cb8178ef428bf738112174fa;hp=1eb49ca7a9f96b4ee191af89b1d97fc80df72e43;hpb=637371f800e71ac4449e01d59571c9d10f6bde26;p=sbcl.git diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c index 1eb49ca..65f50bf 100644 --- a/src/runtime/interrupt.c +++ b/src/runtime/interrupt.c @@ -13,14 +13,44 @@ * files for more information. */ + +/* As far as I can tell, what's going on here is: + * + * In the case of most signals, when Lisp asks us to handle the + * signal, the outermost handler (the one actually passed to UNIX) is + * either interrupt_handle_now(..) or maybe_now_maybe_later(..). + * 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. + * + * o the SIGSEGV (for e.g. Linux) or SIGBUS (for e.g. FreeBSD) used by the + * garbage collector to detect violations of write protection, + * because some cases of such signals (e.g. GC-related violations of + * write protection) are handled at C level and never passed on to + * Lisp. For such signals, we still store any Lisp-level handler + * in interrupt_handlers[..], but for the outermost handle we use + * the value from interrupt_low_level_handlers[..], instead of the + * ordinary interrupt_handle_now(..) or interrupt_handle_later(..). + * + * 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 + * + * - WHN 20000728, dan 20010128 */ + + #include #include #include #include +#include +#include +#include "sbcl.h" #include "runtime.h" #include "arch.h" -#include "sbcl.h" #include "os.h" #include "interrupt.h" #include "globals.h" @@ -31,7 +61,30 @@ #include "alloc.h" #include "dynbind.h" #include "interr.h" +#include "genesis/fdefn.h" +#include "genesis/simple-fun.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); +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) { @@ -52,6 +105,10 @@ void sigaddset_blockable(sigset_t *s) sigaddset(s, SIGWINCH); sigaddset(s, SIGUSR1); sigaddset(s, SIGUSR2); +#ifdef LISP_FEATURE_SB_THREAD + sigaddset(s, SIG_STOP_FOR_GC); + sigaddset(s, SIG_INTERRUPT_THREAD); +#endif } /* When we catch an internal error, should we pass it back to Lisp to @@ -61,76 +118,55 @@ void sigaddset_blockable(sigset_t *s) * becomes 'yes'.) */ boolean internal_errors_enabled = 0; -os_context_t *lisp_interrupt_contexts[MAX_INTERRUPTS]; +struct interrupt_data * global_interrupt_data; -/* As far as I can tell, what's going on here is: - * - * In the case of most signals, when Lisp asks us to handle the - * signal, the outermost handler (the one actually passed to UNIX) is - * either interrupt_handle_now(..) or interrupt_handle_later(..). - * 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. - * - * o the SIGSEGV (for e.g. Linux) or SIGBUS (for e.g. FreeBSD) used by the - * garbage collector to detect violations of write protection, - * because some cases of such signals (e.g. GC-related violations of - * write protection) are handled at C level and never passed on to - * Lisp. For such signals, we still store any Lisp-level handler - * in interrupt_handlers[..], but for the outermost handle we use - * the value from interrupt_low_level_handlers[..], instead of the - * ordinary interrupt_handle_now(..) or interrupt_handle_later(..). - * - * 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 - * - * - WHN 20000728, dan 20010128 */ +/* 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 () +{ + sigset_t new; + sigemptyset(&new); + sigprocmask(SIG_SETMASK,&new,0); +} +#else +void reset_signal_mask () +{ + sigset_t new,old; + int i; + int wrong=0; + sigemptyset(&new); + sigprocmask(SIG_SETMASK,&new,&old); + for(i=1; i>2; - /* FIXME: Ick! Why use abstract "make_fixnum" in some places if - * you're going to convert from fixnum by bare >>2 in other - * places? Use fixnum_value(..) here, and look for other places - * which do bare >> and << for fixnum_value and make_fixnum. */ - + context_index = + fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)); + if (context_index >= MAX_INTERRUPTS) { - lose("maximum interrupt nesting depth (%d) exceeded", - MAX_INTERRUPTS); + lose("maximum interrupt nesting depth (%d) exceeded", MAX_INTERRUPTS); } bind_variable(FREE_INTERRUPT_CONTEXT_INDEX, - make_fixnum(context_index + 1)); + make_fixnum(context_index + 1),thread); - lisp_interrupt_contexts[context_index] = context; + thread->interrupt_contexts[context_index] = context; /* no longer in Lisp now */ foreign_function_call_active = 1; } +/* blocks all blockable signals. If you are calling from a signal handler, + * the usual signal mask will be restored from the context when the handler + * finishes. Otherwise, be careful */ + void undo_fake_foreign_function_call(os_context_t *context) { + struct thread *thread=arch_os_get_current_thread(); /* Block all blockable signals. */ sigset_t block; sigemptyset(&block); @@ -205,14 +267,8 @@ undo_fake_foreign_function_call(os_context_t *context) /* going back into Lisp */ foreign_function_call_active = 0; - /* Undo dynamic binding. */ - /* ### Do I really need to unbind_to_here()? */ - /* FIXME: Is this to undo the binding of - * FREE_INTERRUPT_CONTEXT_INDEX? If so, we should say so. And - * perhaps yes, unbind_to_here() really would be clearer and less - * fragile.. */ - /* dan (2001.08.10) thinks the above supposition is probably correct */ - unbind(); + /* Undo dynamic binding of FREE_INTERRUPT_CONTEXT_INDEX */ + unbind(thread); #ifdef reg_ALLOC /* Put the dynamic space free pointer back into the context. */ @@ -241,7 +297,7 @@ interrupt_internal_error(int signal, siginfo_t *info, os_context_t *context, if (internal_errors_enabled) { SHOW("in interrupt_internal_error"); -#if QSHOW +#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. */ @@ -255,111 +311,77 @@ interrupt_internal_error(int signal, siginfo_t *info, os_context_t *context, * before the Lisp error handling mechanism is set up. */ lose("internal error too early in init, can't recover"); } - undo_fake_foreign_function_call(context); + undo_fake_foreign_function_call(context); /* blocks signals again */ if (continuable) { arch_skip_instruction(context); } } -/* This function handles pending interrupts. Note that in C/kernel - * terms we dealt with the signal already; we just haven't decided - * whether to call a Lisp handler or do a GC or something like that. - * If it helps, you can think of pending_{signal,mask,info} as a - * one-element queue of signals that we have acknowledged but not - * processed */ - void interrupt_handle_pending(os_context_t *context) { -#ifndef __i386__ - boolean were_in_lisp = !foreign_function_call_active; -#endif - - SetSymbolValue(INTERRUPT_PENDING, NIL); - - if (maybe_gc_pending) { - maybe_gc_pending = 0; -#ifndef __i386__ - if (were_in_lisp) -#endif - { - fake_foreign_function_call(context); - } - funcall0(SymbolFunction(MAYBE_GC)); -#ifndef __i386__ - if (were_in_lisp) -#endif - { - undo_fake_foreign_function_call(context); - } - } - - /* FIXME: This isn't very clear. It would be good to reverse - * engineer it and rewrite the code more clearly, or write a clear - * explanation of what's going on in the comments, or both. - * - * WHN's question 1a: How come we unconditionally copy from - * pending_mask into the context, and then test whether - * pending_signal is set? - * - * WHN's question 1b: If pending_signal wasn't set, how could - * pending_mask be valid? - * - * Dan Barlow's reply (sbcl-devel 2001-03-13): And the answer is - - * or appears to be - because interrupt_maybe_gc set it that way - * (look in the #ifndef __i386__ bit). We can't GC during a - * pseudo-atomic, so we set maybe_gc_pending=1 and - * arch_set_pseudo_atomic_interrupted(..) When we come out of - * pseudo_atomic we're marked as interrupted, so we call - * interrupt_handle_pending, which does the GC using the pending - * context (it needs a context so that it has registers to use as - * GC roots) then notices there's no actual interrupt handler to - * call, so doesn't. That's the second question [1b] answered, - * anyway. Why we still need to copy the pending_mask into the - * context given that we're now done with the context anyway, I - * couldn't say. */ -#if 0 - memcpy(os_context_sigmask_addr(context), &pending_mask, - 4 /* sizeof(sigset_t) */ ); -#endif - sigemptyset(&pending_mask); - if (pending_signal) { - int signal = pending_signal; - siginfo_t info; - memcpy(&info, &pending_info, sizeof(siginfo_t)); - pending_signal = 0; - interrupt_handle_now(signal, &info, context); - } + struct thread *thread; + struct interrupt_data *data; + + 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 */ + + memcpy(os_context_sigmask_addr(context), &data->pending_mask, + REAL_SIGSET_SIZE_BYTES); + + 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); } /* * the two main signal handlers: * interrupt_handle_now(..) * maybe_now_maybe_later(..) + * + * to which we have added interrupt_handle_now_handler(..). Why? + * Well, mostly because the SPARC/Linux platform doesn't quite do + * signals the way we want them done. The third argument in the + * handler isn't filled in by the kernel properly, so we fix it up + * ourselves in the arch_os_get_context(..) function; however, we only + * want to do this when we first hit the handler, and not when + * interrupt_handle_now(..) is being called from some other handler + * (when the fixup will already have been done). -- CSR, 2002-07-23 */ void interrupt_handle_now(int signal, siginfo_t *info, void *void_context) { os_context_t *context = (os_context_t*)void_context; -#ifndef __i386__ + struct thread *thread=arch_os_get_current_thread(); +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) boolean were_in_lisp; #endif union interrupt_handler handler; #ifdef LISP_FEATURE_LINUX - /* Under Linux, 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. */ + /* 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]; + handler = thread->interrupt_data->interrupt_handlers[signal]; if (ARE_SAME_HANDLER(handler.c, SIG_IGN)) { return; } -#ifndef __i386__ +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) were_in_lisp = !foreign_function_call_active; if (were_in_lisp) #endif @@ -381,11 +403,18 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) lose("no handler for signal %d in interrupt_handle_now(..)", 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 */ + + /* 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 */ - /* Allocate the SAPs while the interrupts are still disabled. - * (FIXME: Why? This is the way it was done in CMU CL, and it - * even had the comment noting that this is the way it was - * done, but no motivation..) */ lispobj info_sap,context_sap = alloc_sap(context); info_sap = alloc_sap(info); /* Allow signals again. */ @@ -411,11 +440,11 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) (*handler.c)(signal, info, void_context); } -#ifndef __i386__ +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) if (were_in_lisp) #endif { - undo_fake_foreign_function_call(context); + undo_fake_foreign_function_call(context); /* block signals again */ } #ifdef QSHOW_SIGNALS @@ -425,186 +454,406 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) #endif } +/* This is called at the end of a critical section if the indications + * are that some signal was deferred during the section. Note that as + * 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 +run_deferred_handler(struct interrupt_data *data, void *v_context) { + (*(data->pending_handler)) + (data->pending_signal,&(data->pending_info), v_context); + data->pending_handler=0; +} + +boolean +maybe_defer_handler(void *handler, struct interrupt_data *data, + int signal, siginfo_t *info, os_context_t *context) +{ + struct thread *thread=arch_os_get_current_thread(); + if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) { + store_signal_data_for_later(data,handler,signal,info,context); + SetSymbolValue(INTERRUPT_PENDING, T,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 ( +#if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64) + (!foreign_function_call_active) && +#endif + arch_pseudo_atomic_atomic(context)) { + store_signal_data_for_later(data,handler,signal,info,context); + arch_set_pseudo_atomic_interrupted(context); + return 1; + } + return 0; +} static void -maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context) +store_signal_data_for_later (struct interrupt_data *data, void *handler, + int signal, + siginfo_t *info, os_context_t *context) { - os_context_t *context = (os_context_t*)void_context; + data->pending_handler = handler; + data->pending_signal = signal; + if(info) + memcpy(&(data->pending_info), info, sizeof(siginfo_t)); + if(context) { + /* the signal mask in the context (from before we were + * interrupted) is copied to be restored when + * run_deferred_handler happens. Then the usually-blocked + * signals are added to the mask in the context so that we are + * running with blocked signals when the handler returns */ + 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)); + } +} - /* FIXME: See Debian cmucl 2.4.17, and mail from DTC on the CMU CL - * mailing list 23 Oct 1999, for changes in FPU handling at - * interrupt time which should be ported into SBCL. Also see the - * analogous logic at the head of interrupt_handle_now for - * more related FIXME stuff. - */ - + +static void +maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context) +{ + os_context_t *context = arch_os_get_context(&void_context); + struct thread *thread=arch_os_get_current_thread(); + struct interrupt_data *data=thread->interrupt_data; #ifdef LISP_FEATURE_LINUX os_restore_fp_control(context); #endif + if(maybe_defer_handler(interrupt_handle_now,data, + signal,info,context)) + return; + interrupt_handle_now(signal, info, context); +#ifdef LISP_FEATURE_DARWIN + /* Work around G5 bug */ + sigreturn(void_context); +#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; - /* see comments at top of code/signal.lisp for what's going on here - * with INTERRUPTS_ENABLED/INTERRUPT_HANDLE_NOW - */ - if (SymbolValue(INTERRUPTS_ENABLED) == NIL) { - - /* FIXME: This code is exactly the same as the code in the - * other leg of the if(..), and should be factored out into - * a shared function. */ - pending_signal = signal; - memcpy(&pending_info, info, sizeof(siginfo_t)); - memcpy(&pending_mask, - os_context_sigmask_addr(context), - sizeof(sigset_t)); - sigaddset_blockable(os_context_sigmask_addr(context)); - SetSymbolValue(INTERRUPT_PENDING, T); + 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); - } else if ( -#ifndef __i386__ - (!foreign_function_call_active) && -#endif - arch_pseudo_atomic_atomic(context)) { - - /* FIXME: It would probably be good to replace these bare - * memcpy(..) calls with calls to cpy_siginfo_t and - * cpy_sigset_t, so that we only have to get the sizeof - * expressions right in one place, and after that static type - * checking takes over. */ - pending_signal = signal; - memcpy(&pending_info, info, sizeof(siginfo_t)); - memcpy(&pending_mask, - os_context_sigmask_addr(context), - sizeof(sigset_t)); - sigaddset_blockable(os_context_sigmask_addr(context)); + sigemptyset(&ss); + for(i=1;istate=STATE_STOPPED; + + sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC); + sigwaitinfo(&ss,0); + + undo_fake_foreign_function_call(context); } - +#endif + +void +interrupt_handle_now_handler(int signal, siginfo_t *info, void *void_context) +{ + os_context_t *context = arch_os_get_context(&void_context); + interrupt_handle_now(signal, info, context); +#ifdef LISP_FEATURE_DARWIN + sigreturn(void_context); +#endif +} + /* * stuff to detect and handle hitting the GC trigger */ -#ifndef GENCGC /* since GENCGC has its own way to record trigger */ +#ifndef LISP_FEATURE_GENCGC +/* since GENCGC has its own way to record trigger */ static boolean gc_trigger_hit(int signal, siginfo_t *info, os_context_t *context) { if (current_auto_gc_trigger == NULL) return 0; else{ - lispobj *badaddr=(lispobj *)arch_get_bad_addr(signal, - info, - context); + 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 + +/* manipulate the signal context and stack such that when the handler + * returns, it will call function instead of whatever it was doing + * previously + */ + +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) +{ +#ifndef LISP_FEATURE_X86 + void * fun=native_pointer(function); + void *code = &(((struct simple_fun *) fun)->code); +#endif + + /* Build a stack frame showing `interrupted' so that the + * user's backtrace makes (as much) sense (as usual) */ +#ifdef LISP_FEATURE_X86 + /* Suppose the existence of some function that saved all + * registers, called call_into_lisp, then restored GP registers and + * returned. It would look something like this: + + push ebp + mov ebp esp + pushad + push $0 + push $0 + pushl {address of function to call} + call 0x8058db0 + addl $12,%esp + popa + 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 */ + /* 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); + + *(sp-8)=*os_context_register_addr(context,reg_ESP)-8; + *(sp-7)=0; + *(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-2)=*os_context_register_addr(context,reg_EBP); + *(sp-1)=*os_context_pc_addr(context); + +#elif defined(LISP_FEATURE_X86_64) + u64 *sp=(u64 *)*os_context_register_addr(context,reg_RSP); + *(sp-19) = post_signal_tramp; /* return address for call_into_lisp */ + + *(sp-18)=*os_context_register_addr(context,reg_R15); + *(sp-17)=*os_context_register_addr(context,reg_R14); + *(sp-16)=*os_context_register_addr(context,reg_R13); + *(sp-15)=*os_context_register_addr(context,reg_R12); + *(sp-14)=*os_context_register_addr(context,reg_R11); + *(sp-13)=*os_context_register_addr(context,reg_R10); + *(sp-12)=*os_context_register_addr(context,reg_R9); + *(sp-11)=*os_context_register_addr(context,reg_R8); + *(sp-10)=*os_context_register_addr(context,reg_RDI); + *(sp-9)=*os_context_register_addr(context,reg_RSI); + *(sp-8)=*os_context_register_addr(context,reg_RSP)-16; + *(sp-7)=0; + *(sp-6)=*os_context_register_addr(context,reg_RBX); + *(sp-5)=*os_context_register_addr(context,reg_RDX); + *(sp-4)=*os_context_register_addr(context,reg_RCX); + *(sp-3)=*os_context_register_addr(context,reg_RAX); + *(sp-2)=*os_context_register_addr(context,reg_RBP); + *(sp-1)=*os_context_pc_addr(context); + + *os_context_register_addr(context,reg_RDI) = function; /* function */ + *os_context_register_addr(context,reg_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; +#ifdef __NetBSD__ + *os_context_register_addr(context,reg_UESP) = sp-14; +#else + *os_context_register_addr(context,reg_ESP) = sp-14; +#endif +#elif defined(LISP_FEATURE_X86_64) + *os_context_pc_addr(context) = call_into_lisp; + *os_context_register_addr(context,reg_RCX) = 0; + *os_context_register_addr(context,reg_RBP) = sp-2; + *os_context_register_addr(context,reg_RSP) = sp-19; +#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; +#endif +#ifdef ARCH_HAS_NPC_REGISTER + *os_context_npc_addr(context) = + 4 + *os_context_pc_addr(context); +#endif +#ifdef LISP_FEATURE_SPARC + *os_context_register_addr(context,reg_CODE) = + fun + FUN_POINTER_LOWTAG; +#endif +} - return (badaddr >= current_auto_gc_trigger && - badaddr < current_dynamic_space + DYNAMIC_SPACE_SIZE); +#ifdef LISP_FEATURE_SB_THREAD +void interrupt_thread_handler(int num, siginfo_t *info, void *v_context) +{ + os_context_t *context = (os_context_t*)arch_os_get_context(&v_context); + 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 */ + mark_dead_threads(); } + #endif -#ifndef __i386__ -/* This function gets called from the SIGSEGV (for e.g. Linux or +/* 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,void *addr){ + struct thread *th=arch_os_get_current_thread(); + + /* note the os_context hackery here. When the signal handler returns, + * it won't go back to what it was doing ... */ + if(addr >= CONTROL_STACK_GUARD_PAGE(th) && + addr < CONTROL_STACK_GUARD_PAGE(th) + os_vm_page_size) { + /* We hit the end of the control stack: disable guard page + * protection so the error handler has some headroom, protect the + * previous page so that we can catch returns from the guard page + * and restore it. */ + protect_control_stack_guard_page(th->pid,0); + protect_control_stack_return_guard_page(th->pid,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(th->pid,1); + protect_control_stack_return_guard_page(th->pid,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; +} + +#ifndef LISP_FEATURE_GENCGC +/* This function gets called from the SIGSEGV (for e.g. Linux, NetBSD, & * OpenBSD) or SIGBUS (for e.g. FreeBSD) handler. Here we check * whether the signal was due to treading on the mprotect()ed zone - * and if so, arrange for a GC to happen. */ +extern unsigned long bytes_consed_between_gcs; /* gc-common.c */ + boolean interrupt_maybe_gc(int signal, siginfo_t *info, void *void_context) { os_context_t *context=(os_context_t *) void_context; + struct thread *th=arch_os_get_current_thread(); + struct interrupt_data *data= + th ? th->interrupt_data : global_interrupt_data; - if (!foreign_function_call_active -#ifndef GENCGC /* since GENCGC has its own way to record trigger */ - && gc_trigger_hit(signal, info, context) -#endif - ) { -#ifndef GENCGC /* since GENCGC has its own way to record trigger */ + if(!foreign_function_call_active && gc_trigger_hit(signal, info, context)){ clear_auto_gc_trigger(); -#endif - - if (arch_pseudo_atomic_atomic(context)) { - /* don't GC during an atomic operation. Instead, copy the - * signal mask somewhere safe. interrupt_handle_pending - * will detect pending_signal==0 and know to do a GC with the - * signal context instead of calling a Lisp-level handler */ - maybe_gc_pending = 1; - if (pending_signal == 0) { - /* FIXME: This copy-pending_mask-then-sigaddset_blockable - * idiom occurs over and over. It should be factored out - * into a function with a descriptive name. */ - memcpy(&pending_mask, - os_context_sigmask_addr(context), - sizeof(sigset_t)); - sigaddset_blockable(os_context_sigmask_addr(context)); - } - arch_set_pseudo_atomic_interrupted(context); - } - else { - lispobj *old_free_space=current_dynamic_space; - fake_foreign_function_call(context); - funcall0(SymbolFunction(MAYBE_GC)); - undo_fake_foreign_function_call(context); - if(current_dynamic_space==old_free_space) - /* MAYBE-GC (as the name suggest) might not. If it - * doesn't, it won't reset the GC trigger either, so we - * have to do it ourselves. Add small amount of space - * to tide us over while GC is inhibited - */ - set_auto_gc_trigger((u32)dynamic_space_free_pointer - -(u32)current_dynamic_space - +(u32)os_vm_page_size); - } + if(!maybe_defer_handler + (interrupt_maybe_gc_int,data,signal,info,void_context)) + interrupt_maybe_gc_int(signal,info,void_context); return 1; - } else { - return 0; } + return 0; } + #endif + +/* this is also used by gencgc, in alloc() */ +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; + 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. */ + + sigemptyset(&new); + sigaddset_blockable(&new); + /* enable signals before calling into Lisp */ + sigprocmask(SIG_UNBLOCK,&new,0); + funcall0(SymbolFunction(SUB_GC)); + undo_fake_foreign_function_call(context); + return 1; +} + /* * noise to install handlers */ -/* - * what low-level signal handlers looked like before - * undoably_install_low_level_interrupt_handler() got involved - */ -struct low_level_signal_handler_state { - int was_modified; - void (*handler)(int, siginfo_t*, void*); -} old_low_level_signal_handler_states[NSIG]; - -void -uninstall_low_level_interrupt_handlers_atexit(void) -{ - int signal; - for (signal = 0; signal < NSIG; ++signal) { - struct low_level_signal_handler_state - *old_low_level_signal_handler_state = - old_low_level_signal_handler_states + signal; - if (old_low_level_signal_handler_state->was_modified) { - struct sigaction sa; - sa.sa_sigaction = old_low_level_signal_handler_state->handler; - sigemptyset(&sa.sa_mask); - sa.sa_flags = SA_SIGINFO | SA_RESTART; - sigaction(signal, &sa, NULL); - } - } -} - -/* Undoably install a special low-level handler for signal; or if - * handler is SIG_DFL, remove any special handling for signal. - * - * The "undoably" aspect is because we also arrange with atexit() for - * the handler to be restored to its old value. This is for tidiness: - * it shouldn't matter much ordinarily, but it does remove a window - * where e.g. memory fault signals (SIGSEGV or SIGBUS, which in - * ordinary operation of SBCL are sent to the generational garbage - * collector, then possibly onward to Lisp code) or SIGINT (which is - * ordinarily passed to Lisp code) could otherwise be handled - * bizarrely/brokenly because the Lisp code would try to deal with - * them using machinery (like stream output buffers) which has already - * been dismantled. */ void undoably_install_low_level_interrupt_handler (int signal, void handler(int, @@ -612,8 +861,9 @@ undoably_install_low_level_interrupt_handler (int signal, void*)) { struct sigaction sa; - struct low_level_signal_handler_state *old_low_level_signal_handler_state = - old_low_level_signal_handler_states + signal; + 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); @@ -623,19 +873,17 @@ undoably_install_low_level_interrupt_handler (int signal, sigemptyset(&sa.sa_mask); sigaddset_blockable(&sa.sa_mask); sa.sa_flags = SA_SIGINFO | SA_RESTART; - - /* In the case of interrupt handlers which are modified more than - * once, we only save the original unmodified copy. */ - if (!old_low_level_signal_handler_state->was_modified) { - struct sigaction *old_handler = - (struct sigaction*) &old_low_level_signal_handler_state->handler; - old_low_level_signal_handler_state->was_modified = 1; - sigaction(signal, &sa, old_handler); - } else { - sigaction(signal, &sa, NULL); - } - - interrupt_low_level_handlers[signal] = +#ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK + if((signal==SIG_MEMORY_FAULT) +#ifdef SIG_INTERRUPT_THREAD + || (signal==SIG_INTERRUPT_THREAD) +#endif + ) + sa.sa_flags|= SA_ONSTACK; +#endif + + sigaction(signal, &sa, NULL); + data->interrupt_low_level_handlers[signal] = (ARE_SAME_HANDLER(handler, SIG_DFL) ? 0 : handler); } @@ -646,6 +894,9 @@ install_handler(int signal, void handler(int, siginfo_t*, void*)) 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)); @@ -656,27 +907,26 @@ install_handler(int signal, void handler(int, siginfo_t*, void*)) sigemptyset(&new); sigaddset_blockable(&new); - FSHOW((stderr, "/interrupt_low_level_handlers[signal]=%d\n", - interrupt_low_level_handlers[signal])); - if (interrupt_low_level_handlers[signal]==0) { + 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; + 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); } - oldhandler = interrupt_handlers[signal]; - interrupt_handlers[signal].c = handler; + oldhandler = data->interrupt_handlers[signal]; + data->interrupt_handlers[signal].c = handler; sigprocmask(SIG_SETMASK, &old, 0); @@ -686,18 +936,15 @@ install_handler(int signal, void handler(int, siginfo_t*, void*)) } void -interrupt_init(void) +interrupt_init() { int i; - SHOW("entering interrupt_init()"); - - /* Set up for recovery from any installed low-level handlers. */ - atexit(&uninstall_low_level_interrupt_handlers_atexit); + global_interrupt_data=calloc(sizeof(struct interrupt_data), 1); /* Set up high level handler information. */ for (i = 0; i < NSIG; i++) { - interrupt_handlers[i].c = + 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