X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fthread.c;h=206511aa54a5a82d82286b68857b378b4e20358f;hb=44dbdff97fbcc1e5b12e1330da92c5a3dcb94a3b;hp=7706545e371eefdef5e67ecaf1f60a1715c61a3f;hpb=1419c1d2d50f039be46a8667351b7738ac4965e4;p=sbcl.git diff --git a/src/runtime/thread.c b/src/runtime/thread.c index 7706545..206511a 100644 --- a/src/runtime/thread.c +++ b/src/runtime/thread.c @@ -1,7 +1,9 @@ #include #include #include +#include #include +#include #ifndef CLONE_PARENT /* lameass glibc 2.2 doesn't define this */ #define CLONE_PARENT 0x00008000 /* even though the manpage documents it */ #endif @@ -22,7 +24,8 @@ int dynamic_values_bytes=4096*sizeof(lispobj); /* same for all threads */ struct thread *all_threads; -lispobj all_threads_lock; +volatile lispobj all_threads_lock; +volatile int countdown_to_gc; extern struct interrupt_data * global_interrupt_data; void get_spinlock(lispobj *word,int value); @@ -50,8 +53,13 @@ new_thread_trampoline(struct thread *th) fprintf(stderr, "/continue\n"); } th->unbound_marker = UNBOUND_MARKER_WIDETAG; +#ifdef LISP_FEATURE_SB_THREAD /* wait here until our thread is linked into all_threads: see below */ while(th->pid<1) sched_yield(); +#else + if(th->pid < 1) + lose("th->pid not set up right"); +#endif if(arch_os_thread_init(th)==0) return 1; /* failure. no, really */ @@ -114,8 +122,10 @@ pid_t create_thread(lispobj initial_function) { STATIC_TLS_INIT(CONTROL_STACK_START,control_stack_start); STATIC_TLS_INIT(CONTROL_STACK_END,control_stack_end); STATIC_TLS_INIT(ALIEN_STACK,alien_stack_pointer); +#ifdef LISP_FEATURE_X86 STATIC_TLS_INIT(PSEUDO_ATOMIC_ATOMIC,pseudo_atomic_atomic); STATIC_TLS_INIT(PSEUDO_ATOMIC_INTERRUPTED,pseudo_atomic_interrupted); +#endif #undef STATIC_TLS_INIT #endif } @@ -123,22 +133,25 @@ pid_t create_thread(lispobj initial_function) { th->control_stack_start = spaces; th->binding_stack_start= (lispobj*)((void*)th->control_stack_start+THREAD_CONTROL_STACK_SIZE); - th->control_stack_end = th->binding_stack_start-1; + th->control_stack_end = th->binding_stack_start; th->alien_stack_start= (lispobj*)((void*)th->binding_stack_start+BINDING_STACK_SIZE); th->binding_stack_pointer=th->binding_stack_start; th->this=th; th->pid=0; + th->state=STATE_RUNNING; #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD th->alien_stack_pointer=((void *)th->alien_stack_start + ALIEN_STACK_SIZE-4); /* naked 4. FIXME */ #else th->alien_stack_pointer=((void *)th->alien_stack_start); #endif +#ifdef LISP_FEATURE_X86 th->pseudo_atomic_interrupted=0; /* runtime.c used to set PSEUDO_ATOMIC_ATOMIC =1 globally. I'm not * sure why, but it appears to help */ th->pseudo_atomic_atomic=make_fixnum(1); +#endif #ifdef LISP_FEATURE_GENCGC gc_set_region_empty(&th->alloc_region); #endif @@ -169,7 +182,7 @@ pid_t create_thread(lispobj initial_function) { bind_variable(INTERRUPT_PENDING, NIL,th); bind_variable(INTERRUPTS_ENABLED,T,th); - th->interrupt_data=malloc(sizeof (struct interrupt_data)); + th->interrupt_data=os_validate(0,(sizeof (struct interrupt_data))); if(all_threads) memcpy(th->interrupt_data, arch_os_get_current_thread()->interrupt_data, @@ -201,7 +214,7 @@ pid_t create_thread(lispobj initial_function) { * to ensure that we don't have >1 thread with pid=0 on the list at once */ protect_control_stack_guard_page(th->pid,1); - all_threads_lock=0; + release_spinlock(&all_threads_lock); th->pid=kid_pid; /* child will not start until this is set */ #ifndef LISP_FEATURE_SB_THREAD new_thread_trampoline(all_threads); /* call_into_lisp */ @@ -225,6 +238,8 @@ void destroy_thread (struct thread *th) gc_alloc_update_page_tables(0, &th->alloc_region); #endif get_spinlock(&all_threads_lock,th->pid); + if(countdown_to_gc>0) countdown_to_gc--; + th->state=STATE_STOPPED; if(th==all_threads) all_threads=th->next; else { @@ -232,11 +247,12 @@ void destroy_thread (struct thread *th) while(th1->next!=th) th1=th1->next; th1->next=th->next; /* unlink */ } - all_threads_lock=0; + release_spinlock(&all_threads_lock); if(th && th->tls_cookie>=0) arch_os_thread_cleanup(th); os_invalidate((os_vm_address_t) th->control_stack_start, - THREAD_CONTROL_STACK_SIZE+BINDING_STACK_SIZE+ - ALIEN_STACK_SIZE+dynamic_values_bytes+ + ((sizeof (lispobj)) + * (th->control_stack_end-th->control_stack_start)) + + BINDING_STACK_SIZE+ALIEN_STACK_SIZE+dynamic_values_bytes+ 32*SIGSTKSZ); } @@ -249,8 +265,10 @@ struct thread *find_thread_by_pid(pid_t pid) return 0; } - - +/* These are not needed unless #+SB-THREAD, and since sigwaitinfo() + * doesn't seem to be easily available everywhere (OpenBSD...) it's + * more trouble than it's worth to compile it when not needed. */ +#if defined LISP_FEATURE_SB_THREAD void block_sigcont(void) { /* don't allow ourselves to receive SIGCONT while we're in the @@ -258,7 +276,7 @@ void block_sigcont(void) */ sigset_t newset; sigemptyset(&newset); - sigaddset(&newset,SIGCONT); + sigaddset(&newset,SIG_DEQUEUE); sigprocmask(SIG_BLOCK, &newset, 0); } @@ -266,8 +284,79 @@ void unblock_sigcont_and_sleep(void) { sigset_t set; sigemptyset(&set); - sigaddset(&set,SIGCONT); - sigwaitinfo(&set,0); + sigaddset(&set,SIG_DEQUEUE); + do { + errno=0; + sigwaitinfo(&set,0); + }while(errno==EINTR); sigprocmask(SIG_UNBLOCK,&set,0); } +int interrupt_thread(pid_t pid, lispobj function) +{ + union sigval sigval; + sigval.sival_int=function; + + return sigqueue(pid, SIG_INTERRUPT_THREAD, sigval); +} + +/* stopping the world is a two-stage process. From this thread we signal + * all the others with SIG_STOP_FOR_GC. The handler for this thread does + * the usual pseudo-atomic checks (we don't want to stop a thread while + * it's in the middle of allocation) then kills _itself_ with SIGSTOP. + * At any given time, countdown_to_gc should reflect the number of threads + * signalled but which haven't yet come to rest + */ + +void gc_stop_the_world() +{ + /* stop all other threads by sending them SIG_STOP_FOR_GC */ + struct thread *p,*th=arch_os_get_current_thread(); + struct thread *tail=0; + int finished=0; + do { + get_spinlock(&all_threads_lock,th->pid); + if(tail!=all_threads) { + /* new threads always get consed onto the front of all_threads, + * and may be created by any thread that we haven't signalled + * yet or hasn't received our signal and stopped yet. So, check + * for them on each time around */ + for(p=all_threads;p!=tail;p=p->next) { + if(p==th) continue; + /* if the head of all_threads is removed during + * gc_stop_the_world, we may take a second trip through the + * list and end up counting twice as many threads to wait for + * as actually exist */ + if(p->state!=STATE_RUNNING) continue; + countdown_to_gc++; + p->state=STATE_STOPPING; + /* Note no return value check from kill(). If the + * thread had been reaped already, we kill it and + * increment countdown_to_gc anyway. This is to avoid + * complicating the logic in destroy_thread, which would + * otherwise have to know whether the thread died before or + * after it was killed + */ + kill(p->pid,SIG_STOP_FOR_GC); + } + tail=all_threads; + } else { + finished=(countdown_to_gc==0); + } + release_spinlock(&all_threads_lock); + sched_yield(); + } while(!finished); +} + +void gc_start_the_world() +{ + struct thread *p,*th=arch_os_get_current_thread(); + get_spinlock(&all_threads_lock,th->pid); + for(p=all_threads;p;p=p->next) { + if(p==th) continue; + p->state=STATE_RUNNING; + kill(p->pid,SIGCONT); + } + release_spinlock(&all_threads_lock); +} +#endif