X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Finterrupt.c;h=cb85bee726cb0fd8c4040710520e13ed77d642ac;hb=310aee0b439b715a5ec242862ab0a4d254e123b5;hp=bc704e389c640bc811f573cf2c0760aca801365d;hpb=6cde30b92d3e6092372d0164bb47b58568d9360f;p=sbcl.git diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c index bc704e3..cb85bee 100644 --- a/src/runtime/interrupt.c +++ b/src/runtime/interrupt.c @@ -68,14 +68,15 @@ -void run_deferred_handler(struct interrupt_data *data, void *v_context); +static void run_deferred_handler(struct interrupt_data *data, void *v_context); static void store_signal_data_for_later (struct interrupt_data *data, void *handler, int signal, siginfo_t *info, os_context_t *context); boolean interrupt_maybe_gc_int(int signal, siginfo_t *info, void *v_context); -void sigaddset_deferrable(sigset_t *s) +void +sigaddset_deferrable(sigset_t *s) { sigaddset(s, SIGHUP); sigaddset(s, SIGINT); @@ -98,7 +99,8 @@ void sigaddset_deferrable(sigset_t *s) #endif } -void sigaddset_blockable(sigset_t *s) +void +sigaddset_blockable(sigset_t *s) { sigaddset_deferrable(s); #ifdef LISP_FEATURE_SB_THREAD @@ -118,13 +120,14 @@ check_blockables_blocked_or_lose() int i; sigemptyset(&empty); thread_sigmask(SIG_BLOCK, &empty, ¤t); - for(i=0;iinterrupt_data; +#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64) + /* 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); +#endif + if (SymbolValue(GC_INHIBIT,thread)==NIL) { #ifdef LISP_FEATURE_SB_THREAD if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL) { @@ -470,8 +480,8 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) * all our allocation from C now goes through a PA wrapper, * but still, doesn't hurt. * - * Yeah, but non-gencgc platforms that don't really wrap - * allocation in PA. MG - 2005-08-29 */ + * 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); @@ -480,6 +490,7 @@ interrupt_handle_now(int signal, siginfo_t *info, void *void_context) #ifdef LISP_FEATURE_SB_THREAD { sigset_t unblock; + sigemptyset(&unblock); sigaddset(&unblock, SIG_STOP_FOR_GC); thread_sigmask(SIG_UNBLOCK, &unblock, 0); } @@ -518,8 +529,7 @@ 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) { /* The pending_handler may enable interrupts and then another * interrupt may hit, overwrite interrupt_data, so reset the @@ -684,10 +694,6 @@ sig_stop_for_gc_handler(int signal, siginfo_t *info, void *void_context) sigfillset(&ss); /* Block everything. */ thread_sigmask(SIG_BLOCK,&ss,0); - /* The GC can't tell if a thread is a zombie, so this would be a - * good time to let the kernel reap any of our children in that - * awful state, to stop them from being waited for indefinitely. - * Userland reaping is done later when GC is finished */ if(thread->state!=STATE_RUNNING) { lose("sig_stop_for_gc_handler: wrong thread state: %ld\n", fixnum_value(thread->state)); @@ -696,7 +702,9 @@ sig_stop_for_gc_handler(int signal, siginfo_t *info, void *void_context) FSHOW_SIGNAL((stderr,"thread=%lu suspended\n",thread->os_thread)); sigemptyset(&ss); sigaddset(&ss,SIG_STOP_FOR_GC); - sigwaitinfo(&ss,0); + /* It is possible to get SIGCONT (and probably other + * non-blockable signals) here. */ + while (sigwaitinfo(&ss,0) != SIG_STOP_FOR_GC); 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", @@ -743,12 +751,13 @@ gc_trigger_hit(int signal, siginfo_t *info, os_context_t *context) */ #if (defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)) -int *context_eflags_addr(os_context_t *context); +extern int *context_eflags_addr(os_context_t *context); #endif extern lispobj call_into_lisp(lispobj fun, lispobj *args, int nargs); extern void post_signal_tramp(void); -void arrange_return_to_lisp_function(os_context_t *context, lispobj function) +void +arrange_return_to_lisp_function(os_context_t *context, lispobj function) { #if !(defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)) void * fun=native_pointer(function); @@ -885,7 +894,8 @@ void arrange_return_to_lisp_function(os_context_t *context, lispobj function) /* 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) +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 */ @@ -901,11 +911,13 @@ void interrupt_thread_handler(int num, siginfo_t *info, void *v_context) * that has the added benefit of automatically discriminating between * functions and variables. */ -void undefined_alien_function() { +void +undefined_alien_function() { funcall0(SymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR)); } -boolean handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr) +boolean +handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr) { struct thread *th=arch_os_get_current_thread(); @@ -1018,6 +1030,7 @@ interrupt_maybe_gc_int(int signal, siginfo_t *info, void *void_context) #ifdef LISP_FEATURE_SB_THREAD else { sigset_t new; + sigemptyset(&new); sigaddset(&new,SIG_STOP_FOR_GC); thread_sigmask(SIG_UNBLOCK,&new,0); } @@ -1033,6 +1046,73 @@ interrupt_maybe_gc_int(int signal, siginfo_t *info, void *void_context) * noise to install handlers */ +/* 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. + */ +static volatile int sigaction_nodefer_works = -1; + +static void +sigaction_nodefer_test_handler(int signal, siginfo_t *info, void *void_context) +{ + sigset_t empty, current; + int i; + sigemptyset(&empty); + sigprocmask(SIG_BLOCK, &empty, ¤t); + for(i = 1; i < NSIG; i++) + if (sigismember(¤t, i) != ((i == SIGABRT) ? 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, SIGABRT); + sigaction(SIGUSR1, &sa, &old_sa); + /* Make sure no signals are blocked. */ + { + sigset_t empty; + sigemptyset(&empty); + sigprocmask(SIG_SETMASK, &empty, 0); + } + kill(getpid(), SIGUSR1); + while (sigaction_nodefer_works == -1); + sigaction(SIGUSR1, &old_sa, NULL); +} + +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, @@ -1045,13 +1125,19 @@ undoably_install_low_level_interrupt_handler (int signal, lose("bad signal number %d", signal); } - if (sigismember(&deferrable_sigset,signal)) + 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; + else if (!sigaction_nodefer_works && + !sigismember(&blockable_sigset, signal)) + sa.sa_sigaction = low_level_unblock_me_trampoline; else sa.sa_sigaction = handler; sigcopyset(&sa.sa_mask, &blockable_sigset); - sa.sa_flags = SA_SIGINFO | SA_RESTART; + 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 @@ -1084,16 +1170,19 @@ install_handler(int signal, void handler(int, siginfo_t*, void*)) (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)) { + ARE_SAME_HANDLER(handler, SIG_IGN)) sa.sa_sigaction = handler; - } else if (sigismember(&deferrable_sigset, signal)) { + else if (sigismember(&deferrable_sigset, signal)) sa.sa_sigaction = maybe_now_maybe_later; - } else { + 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; + sa.sa_flags = SA_SIGINFO | SA_RESTART | + (sigaction_nodefer_works ? SA_NODEFER : 0); sigaction(signal, &sa, NULL); } @@ -1112,6 +1201,7 @@ interrupt_init() { int i; SHOW("entering interrupt_init()"); + see_if_sigaction_nodefer_works(); sigemptyset(&deferrable_sigset); sigemptyset(&blockable_sigset); sigaddset_deferrable(&deferrable_sigset);