X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fthread.c;h=759a1c649f6fbd69689506274d569cbec10fcc2b;hb=dc71db379ab4162a45c393a2e828f619dae9fa32;hp=42a8b0729d90ce124c781e9f43a930fe451f176a;hpb=1b8bf3eb32049318ac5024e84cdf8925ec4aabae;p=sbcl.git diff --git a/src/runtime/thread.c b/src/runtime/thread.c index 42a8b07..759a1c6 100644 --- a/src/runtime/thread.c +++ b/src/runtime/thread.c @@ -5,8 +5,11 @@ #include #include #include -#include "runtime.h" +#include +#include + #include "sbcl.h" +#include "runtime.h" #include "validate.h" /* for CONTROL_STACK_SIZE etc */ #include "thread.h" #include "arch.h" @@ -15,27 +18,34 @@ #include "globals.h" #include "dynbind.h" #include "genesis/cons.h" +#include "genesis/fdefn.h" +#include "interr.h" /* for lose() */ +#include "gc-internal.h" + #define ALIEN_STACK_SIZE (1*1024*1024) /* 1Mb size chosen at random */ int dynamic_values_bytes=4096*sizeof(lispobj); /* same for all threads */ struct thread *all_threads; volatile lispobj all_threads_lock; +volatile lispobj thread_start_lock; extern struct interrupt_data * global_interrupt_data; - -void get_spinlock(lispobj *word,int value); +extern int linux_no_threads_p; int initial_thread_trampoline(struct thread *th) { lispobj function; +#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64) lispobj *args = NULL; +#endif + function = th->unbound_marker; th->unbound_marker = UNBOUND_MARKER_WIDETAG; if(arch_os_thread_init(th)==0) return 1; if(th->pid < 1) lose("th->pid not set up right"); th->state=STATE_RUNNING; -#if defined(LISP_FEATURE_X86) +#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64) return call_into_lisp_first_time(function,args,0); #else return funcall0(function); @@ -83,16 +93,15 @@ struct thread * create_thread_struct(lispobj initial_function) { BINDING_STACK_SIZE+ ALIEN_STACK_SIZE+ dynamic_values_bytes+ - 32*SIGSTKSZ - ); - if(!spaces) goto cleanup; + 32*SIGSTKSZ); + if(!spaces) + return NULL; per_thread=(union per_thread_data *) (spaces+ THREAD_CONTROL_STACK_SIZE+ BINDING_STACK_SIZE+ ALIEN_STACK_SIZE); - th=&per_thread->thread; if(all_threads) { memcpy(per_thread,arch_os_get_current_thread(), dynamic_values_bytes); @@ -124,6 +133,7 @@ struct thread * create_thread_struct(lispobj initial_function) { #endif } + th=&per_thread->thread; th->control_stack_start = spaces; th->binding_stack_start= (lispobj*)((void*)th->control_stack_start+THREAD_CONTROL_STACK_SIZE); @@ -133,14 +143,14 @@ struct thread * create_thread_struct(lispobj initial_function) { th->binding_stack_pointer=th->binding_stack_start; th->this=th; th->pid=0; - th->state=STATE_STOPPED; + th->state=STATE_STARTING; #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD th->alien_stack_pointer=((void *)th->alien_stack_start - + ALIEN_STACK_SIZE-4); /* naked 4. FIXME */ + + ALIEN_STACK_SIZE-N_WORD_BYTES); #else th->alien_stack_pointer=((void *)th->alien_stack_start); #endif -#ifdef LISP_FEATURE_X86 +#if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64) th->pseudo_atomic_interrupted=0; th->pseudo_atomic_atomic=0; #endif @@ -155,13 +165,13 @@ struct thread * create_thread_struct(lispobj initial_function) { * we use the appropriate SymbolValue macros to access any of the * variable quantities from the C runtime. It's not quite OAOOM, * it just feels like it */ - SetSymbolValue(BINDING_STACK_START,th->binding_stack_start,th); - SetSymbolValue(CONTROL_STACK_START,th->control_stack_start,th); - SetSymbolValue(CONTROL_STACK_END,th->control_stack_end,th); -#ifdef LISP_FEATURE_X86 - SetSymbolValue(BINDING_STACK_POINTER,th->binding_stack_pointer,th); - SetSymbolValue(ALIEN_STACK,th->alien_stack_pointer,th); - SetSymbolValue(PSEUDO_ATOMIC_ATOMIC,th->pseudo_atomic_atomic,th); + SetSymbolValue(BINDING_STACK_START,(lispobj)th->binding_stack_start,th); + SetSymbolValue(CONTROL_STACK_START,(lispobj)th->control_stack_start,th); + SetSymbolValue(CONTROL_STACK_END,(lispobj)th->control_stack_end,th); +#if defined(LISP_FEATURE_X86) || defined (LISP_FEATURE_X86_64) + SetSymbolValue(BINDING_STACK_POINTER,(lispobj)th->binding_stack_pointer,th); + SetSymbolValue(ALIEN_STACK,(lispobj)th->alien_stack_pointer,th); + SetSymbolValue(PSEUDO_ATOMIC_ATOMIC,(lispobj)th->pseudo_atomic_atomic,th); SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED,th->pseudo_atomic_interrupted,th); #else current_binding_stack_pointer=th->binding_stack_pointer; @@ -174,7 +184,8 @@ struct thread * create_thread_struct(lispobj initial_function) { bind_variable(INTERRUPT_PENDING, NIL,th); bind_variable(INTERRUPTS_ENABLED,T,th); - th->interrupt_data=os_validate(0,(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, @@ -185,16 +196,15 @@ struct thread * create_thread_struct(lispobj initial_function) { th->unbound_marker=initial_function; return th; - cleanup: - /* if(th && th->tls_cookie>=0) os_free_tls_pointer(th); */ - if(spaces) os_invalidate(spaces, - THREAD_CONTROL_STACK_SIZE+BINDING_STACK_SIZE+ - ALIEN_STACK_SIZE+dynamic_values_bytes); - return 0; } void link_thread(struct thread *th,pid_t kid_pid) { + sigset_t newset,oldset; + sigemptyset(&newset); + sigaddset_blockable(&newset); + sigprocmask(SIG_BLOCK, &newset, &oldset); + get_spinlock(&all_threads_lock,kid_pid); th->next=all_threads; all_threads=th; @@ -202,8 +212,10 @@ void link_thread(struct thread *th,pid_t kid_pid) * 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); - release_spinlock(&all_threads_lock); th->pid=kid_pid; /* child will not start until this is set */ + release_spinlock(&all_threads_lock); + + sigprocmask(SIG_SETMASK,&oldset,0); } void create_initial_thread(lispobj initial_function) { @@ -217,48 +229,49 @@ void create_initial_thread(lispobj initial_function) { #ifdef LISP_FEATURE_SB_THREAD pid_t create_thread(lispobj initial_function) { - struct thread *th=create_thread_struct(initial_function); - pid_t kid_pid=clone(new_thread_trampoline, - (((void*)th->control_stack_start)+ - THREAD_CONTROL_STACK_SIZE-4), - CLONE_FILES|SIG_THREAD_EXIT|CLONE_VM,th); + struct thread *th; + pid_t kid_pid=0; - if(th && kid_pid>0) { + if(linux_no_threads_p) return 0; + th=create_thread_struct(initial_function); + if(th==0) return 0; +#ifdef QSHOW_SIGNALS + SHOW("create_thread:waiting on lock"); +#endif + get_spinlock(&thread_start_lock,arch_os_get_current_thread()->pid); +#ifdef QSHOW_SIGNALS + SHOW("create_thread:got lock"); +#endif + kid_pid=clone(new_thread_trampoline, + (((void*)th->control_stack_start)+ + THREAD_CONTROL_STACK_SIZE-16), + CLONE_FILES|SIG_THREAD_EXIT|CLONE_VM,th); + + if(kid_pid>0) { link_thread(th,kid_pid); + /* wait here until our thread is started: see new_thread_trampoline */ + while(th->state==STATE_STARTING) sched_yield(); + /* it's started and initialized, it's safe to gc */ + release_spinlock(&thread_start_lock); +#ifdef QSHOW_SIGNALS + SHOW("create_thread:released lock"); +#endif return th->pid; } else { - destroy_thread(th); + release_spinlock(&thread_start_lock); +#ifdef QSHOW_SIGNALS + SHOW("create_thread:released lock(failure)"); +#endif + os_invalidate((os_vm_address_t) th->control_stack_start, + ((sizeof (lispobj)) + * (th->control_stack_end-th->control_stack_start)) + + BINDING_STACK_SIZE+ALIEN_STACK_SIZE+dynamic_values_bytes+ + 32*SIGSTKSZ); return 0; } } #endif -void destroy_thread (struct thread *th) -{ - /* precondition: the unix task has already been killed and exited. - * This is called by the parent */ -#ifdef LISP_FEATURE_GENCGC - gc_alloc_update_page_tables(0, &th->alloc_region); -#endif - get_spinlock(&all_threads_lock,th->pid); - th->state=STATE_STOPPED; - if(th==all_threads) - all_threads=th->next; - else { - struct thread *th1=all_threads; - while(th1 && th1->next!=th) th1=th1->next; - if(th1) th1->next=th->next; /* unlink */ - } - 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, - ((sizeof (lispobj)) - * (th->control_stack_end-th->control_stack_start)) + - BINDING_STACK_SIZE+ALIEN_STACK_SIZE+dynamic_values_bytes+ - 32*SIGSTKSZ); -} - - struct thread *find_thread_by_pid(pid_t pid) { struct thread *th; @@ -267,39 +280,60 @@ 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) +/* This is not needed unless #+SB-THREAD, as there's a trivial null + * unithread definition. */ + +void mark_dead_threads() { - /* don't allow ourselves to receive SIGCONT while we're in the - * "ambiguous" state of being on the queue but not actually stopped. - */ - sigset_t newset; - sigemptyset(&newset); - sigaddset(&newset,SIG_DEQUEUE); - sigprocmask(SIG_BLOCK, &newset, 0); + pid_t kid; + int status; + while(1) { + kid=waitpid(-1,&status,__WALL|WNOHANG); + if(kid<=0) break; + if(WIFEXITED(status) || WIFSIGNALED(status)) { + struct thread *th=find_thread_by_pid(kid); + if(th) th->state=STATE_DEAD; + } + } } -void unblock_sigcont_and_sleep(void) +void reap_dead_threads() { - sigset_t set; - sigemptyset(&set); - sigaddset(&set,SIG_DEQUEUE); - do { - errno=0; - sigwaitinfo(&set,0); - }while(errno==EINTR); - sigprocmask(SIG_UNBLOCK,&set,0); + struct thread *th,*next,*prev=0; + th=all_threads; + while(th) { + next=th->next; + if(th->state==STATE_DEAD) { + funcall1(SymbolFunction(HANDLE_THREAD_EXIT),make_fixnum(th->pid)); +#ifdef LISP_FEATURE_GENCGC + gc_alloc_update_page_tables(0, &th->alloc_region); +#endif + get_spinlock(&all_threads_lock,th->pid); + if(prev) prev->next=next; + else all_threads=next; + release_spinlock(&all_threads_lock); + if(th->tls_cookie>=0) arch_os_thread_cleanup(th); + os_invalidate((os_vm_address_t) th->control_stack_start, + ((sizeof (lispobj)) + * (th->control_stack_end-th->control_stack_start)) + + BINDING_STACK_SIZE+ALIEN_STACK_SIZE+dynamic_values_bytes+ + 32*SIGSTKSZ); + } else + prev=th; + th=next; + } } int interrupt_thread(pid_t pid, lispobj function) { union sigval sigval; + struct thread *th; sigval.sival_int=function; - - return sigqueue(pid, SIG_INTERRUPT_THREAD, sigval); + for_each_thread(th) + if((th->pid==pid) && (th->state != STATE_DEAD)) + return sigqueue(pid, SIG_INTERRUPT_THREAD, sigval); + errno=EPERM; return -1; } int signal_thread_to_dequeue (pid_t pid) @@ -309,49 +343,82 @@ int signal_thread_to_dequeue (pid_t pid) /* 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 + * all the others with SIG_STOP_FOR_GC. The handler for this signal 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. + * it's in the middle of allocation) then waits for another SIG_STOP_FOR_GC. */ void gc_stop_the_world() { - /* stop all other threads by sending them SIG_STOP_FOR_GC */ +#ifdef QSHOW_SIGNALS + SHOW("gc_stop_the_world:begin"); +#endif struct thread *p,*th=arch_os_get_current_thread(); - pid_t old_pid; - int finished=0; - do { - get_spinlock(&all_threads_lock,th->pid); - for(p=all_threads,old_pid=p->pid; p; p=p->next) { - if(p==th) continue; - if(p->state!=STATE_RUNNING) continue; - p->state=STATE_STOPPING; - kill(p->pid,SIG_STOP_FOR_GC); - } - release_spinlock(&all_threads_lock); - sched_yield(); - /* if everything has stopped, and there is no possibility that - * a new thread has been created, we're done. Otherwise go - * round again and signal anything that sprang up since last - * time */ - if(old_pid==all_threads->pid) { - finished=1; - for_each_thread(p) - finished = finished && - ((p==th) || (p->state==STATE_STOPPED)); - } - } while(!finished); + /* keep threads from starting while the world is stopped. */ + get_spinlock(&thread_start_lock,th->pid); +#ifdef QSHOW_SIGNALS + SHOW("gc_stop_the_world:locked"); +#endif + /* stop all other threads by sending them SIG_STOP_FOR_GC */ + for(p=all_threads; p; p=p->next) { + if((p!=th) && (p->pid!=0) && (p->state==STATE_RUNNING)) { + p->state=STATE_STOPPING; + if(kill(p->pid,SIG_STOP_FOR_GC)==-1) { + /* we can't kill the process; assume because it + * died already (and its parent is dead so never + * saw the SIGCHLD) */ + p->state=STATE_DEAD; + } + } + } +#ifdef QSHOW_SIGNALS + SHOW("gc_stop_the_world:signals sent"); +#endif + /* wait for the running threads to stop */ + for(p=all_threads;p;) { + if((p==th) || (p->pid==0) || (p->state==STATE_STARTING) || + (p->state==STATE_DEAD) || (p->state==STATE_STOPPED)) { + p=p->next; + } + } +#ifdef QSHOW_SIGNALS + SHOW("gc_stop_the_world:end"); +#endif } void gc_start_the_world() { struct thread *p,*th=arch_os_get_current_thread(); - get_spinlock(&all_threads_lock,th->pid); + /* if a resumed thread creates a new thread before we're done with + * this loop, the new thread will get consed on the front of + * all_threads, but it won't have been stopped so won't need + * restarting; there can be threads just starting from before + * gc_stop_the_world, though */ +#ifdef QSHOW_SIGNALS + SHOW("gc_start_the_world:begin"); +#endif for(p=all_threads;p;p=p->next) { - if(p==th) continue; - p->state=STATE_RUNNING; - kill(p->pid,SIG_STOP_FOR_GC); + if((p!=th) && (p->pid!=0) && (p->state!=STATE_STARTING) && + (p->state!=STATE_DEAD)) { + if(p->state!=STATE_STOPPED) { + lose("gc_start_the_world: wrong thread state is %ld\n", + fixnum_value(p->state)); + } + kill(p->pid,SIG_STOP_FOR_GC); + } } - release_spinlock(&all_threads_lock); + /* we must wait for all threads to leave stopped state else we + * risk signal accumulation and lose any meaning of + * thread->state */ + for(p=all_threads;p;) { + gc_assert(p->state!=STATE_STOPPING); + if((p==th) || (p->pid==0) || (p->state!=STATE_STOPPED)) { + p=p->next; + } + } + release_spinlock(&thread_start_lock); +#ifdef QSHOW_SIGNALS + SHOW("gc_start_the_world:end"); +#endif } #endif