X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fthread.c;h=42a8b0729d90ce124c781e9f43a930fe451f176a;hb=ba4659ad35f28a8fefa4a10c3c7012e4ba50d683;hp=8bd4488b4b4b3e5195804b3046ca39a002ff6dbf;hpb=a9ccc34071513a13b439eaadebfd3c05dd940392;p=sbcl.git diff --git a/src/runtime/thread.c b/src/runtime/thread.c index 8bd4488..42a8b07 100644 --- a/src/runtime/thread.c +++ b/src/runtime/thread.c @@ -1,12 +1,10 @@ #include #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 #include "runtime.h" #include "sbcl.h" #include "validate.h" /* for CONTROL_STACK_SIZE etc */ @@ -15,9 +13,6 @@ #include "target-arch-os.h" #include "os.h" #include "globals.h" -#ifdef LISP_FEATURE_GENCGC -#include "gencgc.h" -#endif #include "dynbind.h" #include "genesis/cons.h" #define ALIEN_STACK_SIZE (1*1024*1024) /* 1Mb size chosen at random */ @@ -25,61 +20,60 @@ int dynamic_values_bytes=4096*sizeof(lispobj); /* same for all threads */ struct thread *all_threads; volatile lispobj all_threads_lock; -volatile int countdown_to_gc; extern struct interrupt_data * global_interrupt_data; void get_spinlock(lispobj *word,int value); +int +initial_thread_trampoline(struct thread *th) +{ + lispobj function; + lispobj *args = NULL; + 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) + return call_into_lisp_first_time(function,args,0); +#else + return funcall0(function); +#endif +} + /* this is the first thing that clone() runs in the child (which is * why the silly calling convention). Basically it calls the user's * requested lisp function after doing arch_os_thread_init and * whatever other bookkeeping needs to be done */ -/* set go to 0 to stop the thread before it starts. Convenient if you -* want to attach a debugger to it before it does anything */ -volatile int go=1; - +#ifdef LISP_FEATURE_SB_THREAD int new_thread_trampoline(struct thread *th) { lispobj function; - lispobj *args = NULL; function = th->unbound_marker; - if(go==0) { - fprintf(stderr, "/pausing 0x%lx(%d,%d) before new_thread_trampoline(0x%lx)\n", - (unsigned long)th,th->pid,getpid(),(unsigned long)function); - while(go==0) ; - fprintf(stderr, "/continue\n"); - } th->unbound_marker = UNBOUND_MARKER_WIDETAG; -#ifdef LISP_FEATURE_SB_THREAD + if(arch_os_thread_init(th)==0) return 1; + /* 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 */ -#if !defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_X86) - return call_into_lisp_first_time(function,args,0); -#else + th->state=STATE_RUNNING; return funcall0(function); -#endif } +#endif /* LISP_FEATURE_SB_THREAD */ /* this is called from any other thread to create the new one, and * initialize all parts of it that can be initialized from another * thread */ -pid_t create_thread(lispobj initial_function) { +struct thread * create_thread_struct(lispobj initial_function) { union per_thread_data *per_thread; struct thread *th=0; /* subdue gcc */ void *spaces=0; - pid_t kid_pid; /* may as well allocate all the spaces at once: it saves us from * having to decide what to do if only some of the allocations @@ -139,6 +133,7 @@ pid_t create_thread(lispobj initial_function) { th->binding_stack_pointer=th->binding_stack_start; th->this=th; th->pid=0; + th->state=STATE_STOPPED; #ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD th->alien_stack_pointer=((void *)th->alien_stack_start + ALIEN_STACK_SIZE-4); /* naked 4. FIXME */ @@ -147,9 +142,7 @@ pid_t create_thread(lispobj initial_function) { #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); + th->pseudo_atomic_atomic=0; #endif #ifdef LISP_FEATURE_GENCGC gc_set_region_empty(&th->alloc_region); @@ -191,21 +184,17 @@ pid_t create_thread(lispobj initial_function) { sizeof (struct interrupt_data)); th->unbound_marker=initial_function; -#ifdef LISP_FEATURE_SB_THREAD -#if defined(LISP_FEATURE_X86) && defined (LISP_FEATURE_LINUX) - kid_pid= - clone(new_thread_trampoline, - (((void*)th->control_stack_start)+THREAD_CONTROL_STACK_SIZE-4), - (((getpid()!=parent_pid)?(CLONE_PARENT):0) - |CLONE_FILES|SIGALRM|CLONE_VM),th); - if(kid_pid<=0) - goto cleanup; -#else -#error this stuff presently only works on x86 Linux -#endif -#else - kid_pid=getpid(); -#endif + 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) +{ get_spinlock(&all_threads_lock,kid_pid); th->next=all_threads; all_threads=th; @@ -215,19 +204,34 @@ pid_t create_thread(lispobj initial_function) { 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 */ -#ifndef LISP_FEATURE_SB_THREAD - new_thread_trampoline(all_threads); /* call_into_lisp */ - lose("Clever child? Idiot savant, verging on the."); -#endif +} - return th->pid; - 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 create_initial_thread(lispobj initial_function) { + struct thread *th=create_thread_struct(initial_function); + pid_t kid_pid=getpid(); + if(th && kid_pid>0) { + link_thread(th,kid_pid); + initial_thread_trampoline(all_threads); /* no return */ + } else lose("can't create initial thread"); +} + +#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); + + if(th && kid_pid>0) { + link_thread(th,kid_pid); + return th->pid; + } else { + destroy_thread(th); + return 0; + } } +#endif void destroy_thread (struct thread *th) { @@ -237,14 +241,13 @@ 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 { struct thread *th1=all_threads; - while(th1->next!=th) th1=th1->next; - th1->next=th->next; /* unlink */ + 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); @@ -299,51 +302,44 @@ int interrupt_thread(pid_t pid, lispobj function) return sigqueue(pid, SIG_INTERRUPT_THREAD, sigval); } +int signal_thread_to_dequeue (pid_t pid) +{ + return kill (pid, SIG_DEQUEUE); +} + + /* 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; + pid_t old_pid; 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); + 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); } @@ -354,7 +350,7 @@ void gc_start_the_world() for(p=all_threads;p;p=p->next) { if(p==th) continue; p->state=STATE_RUNNING; - kill(p->pid,SIGCONT); + kill(p->pid,SIG_STOP_FOR_GC); } release_spinlock(&all_threads_lock); }