#define ALIEN_STACK_SIZE (1*1024*1024) /* 1Mb size chosen at random */
+struct freeable_stack {
+ os_thread_t os_thread;
+ os_vm_address_t stack;
+};
+
+static struct freeable_stack * volatile freeable_stack = 0;
+
int dynamic_values_bytes=4096*sizeof(lispobj); /* same for all threads */
struct thread * volatile all_threads;
extern struct interrupt_data * global_interrupt_data;
pthread_mutex_t all_threads_lock = PTHREAD_MUTEX_INITIALIZER;
-/* When trying to get all_threads_lock one should make sure that
- * sig_stop_for_gc is not blocked. Else there would be a possible
- * deadlock: gc locks it, other thread blocks signals, gc sends stop
- * request to other thread and waits, other thread blocks on lock. */
-void check_sig_stop_for_gc_can_arrive_or_lose()
-{
- /* Get the current sigmask, by blocking the empty set. */
- sigset_t empty,current;
- sigemptyset(&empty);
- thread_sigmask(SIG_BLOCK, &empty, ¤t);
- if (sigismember(¤t,SIG_STOP_FOR_GC))
- lose("SIG_STOP_FOR_GC cannot arrive: it is blocked\n");
- if (SymbolValue(GC_INHIBIT,arch_os_get_current_thread()) != NIL)
- lose("SIG_STOP_FOR_GC cannot arrive: gc is inhibited\n");
- if (arch_pseudo_atomic_atomic(NULL))
- lose("SIG_STOP_FOR_GC cannot arrive: in pseudo atomic\n");
-}
+#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
+extern lispobj call_into_lisp_first_time(lispobj fun, lispobj *args, int nargs);
+#endif
-#define GET_ALL_THREADS_LOCK(name) \
- { \
- sigset_t _newset,_oldset; \
- sigemptyset(&_newset); \
- sigaddset_deferrable(&_newset); \
- thread_sigmask(SIG_BLOCK, &_newset, &_oldset); \
- check_sig_stop_for_gc_can_arrive_or_lose(); \
- FSHOW_SIGNAL((stderr,"/%s:waiting on lock=%ld, thread=%lu\n",name, \
- all_threads_lock,arch_os_get_current_thread()->os_thread)); \
- pthread_mutex_lock(&all_threads_lock); \
- FSHOW_SIGNAL((stderr,"/%s:got lock, thread=%lu\n", \
- name,arch_os_get_current_thread()->os_thread));
-
-#define RELEASE_ALL_THREADS_LOCK(name) \
- FSHOW_SIGNAL((stderr,"/%s:released lock\n",name)); \
- pthread_mutex_unlock(&all_threads_lock); \
- thread_sigmask(SIG_SETMASK,&_oldset,0); \
- }
#endif
+static void
+link_thread(struct thread *th)
+{
+ th->os_thread=thread_self();
+ if (all_threads) all_threads->prev=th;
+ th->next=all_threads;
+ th->prev=0;
+ all_threads=th;
+ protect_control_stack_guard_page(1);
+}
-#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
-extern lispobj call_into_lisp_first_time(lispobj fun, lispobj *args, int nargs);
+#ifdef LISP_FEATURE_SB_THREAD
+static void
+unlink_thread(struct thread *th)
+{
+ if (th->prev)
+ th->prev->next = th->next;
+ else
+ all_threads = th->next;
+ if (th->next)
+ th->next->prev = th->prev;
+}
#endif
static int
function = th->no_tls_value_marker;
th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
if(arch_os_thread_init(th)==0) return 1;
+ link_thread(th);
- if(th->os_thread < 1) lose("th->os_thread not set up right");
- th->state=STATE_RUNNING;
#if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
return call_into_lisp_first_time(function,args,0);
#else
#endif
}
+#define THREAD_STRUCT_SIZE (THREAD_CONTROL_STACK_SIZE + BINDING_STACK_SIZE + \
+ ALIEN_STACK_SIZE + dynamic_values_bytes + \
+ 32 * SIGSTKSZ)
+
#ifdef LISP_FEATURE_SB_THREAD
+static void
+free_thread_stack_later(struct thread *thread_to_be_cleaned_up)
+{
+ struct freeable_stack *new_freeable_stack = 0;
+ if (thread_to_be_cleaned_up) {
+ new_freeable_stack = (struct freeable_stack *)
+ os_validate(0, sizeof(struct freeable_stack));
+ new_freeable_stack->os_thread = thread_to_be_cleaned_up->os_thread;
+ new_freeable_stack->stack = (os_vm_address_t)
+ thread_to_be_cleaned_up->control_stack_start;
+ }
+ new_freeable_stack = (struct freeable_stack *)
+ swap_lispobjs((lispobj *)(void *)&freeable_stack,
+ (lispobj)new_freeable_stack);
+ if (new_freeable_stack) {
+ FSHOW((stderr,"/reaping %lu\n", new_freeable_stack->os_thread));
+ /* Under NPTL pthread_join really waits until the thread
+ * exists and the stack can be safely freed. This is sadly not
+ * mandated by the pthread spec. */
+ gc_assert(pthread_join(new_freeable_stack->os_thread, NULL) == 0);
+ os_invalidate(new_freeable_stack->stack, THREAD_STRUCT_SIZE);
+ os_invalidate((os_vm_address_t) new_freeable_stack,
+ sizeof(struct freeable_stack));
+ }
+}
+
/* this is the first thing that 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
{
lispobj function;
int result;
+ FSHOW((stderr,"/creating thread %lu\n", thread_self()));
function = th->no_tls_value_marker;
th->no_tls_value_marker = NO_TLS_VALUE_MARKER_WIDETAG;
if(arch_os_thread_init(th)==0) {
lose("arch_os_thread_init failed\n");
}
- /* wait here until our thread is linked into all_threads: see below */
- {
- volatile os_thread_t *tid=&th->os_thread;
- while(*tid<1) sched_yield();
- }
+ /* Since GC can only know about this thread from the all_threads
+ * list and we're just adding this thread to it there is no danger
+ * of deadlocking even with SIG_STOP_FOR_GC blocked. */
+ pthread_mutex_lock(&all_threads_lock);
+ link_thread(th);
+ pthread_mutex_unlock(&all_threads_lock);
- th->state=STATE_RUNNING;
result = funcall0(function);
th->state=STATE_DEAD;
+
+ /* SIG_STOP_FOR_GC is blocked and GC might be waiting for this
+ * thread, but since we are already dead it won't wait long. */
+ pthread_mutex_lock(&all_threads_lock);
+ unlink_thread(th);
+ pthread_mutex_unlock(&all_threads_lock);
+
+ gc_alloc_update_page_tables(0, &th->alloc_region);
+ if(th->tls_cookie>=0) arch_os_thread_cleanup(th);
+ os_invalidate((os_vm_address_t)th->interrupt_data,
+ (sizeof (struct interrupt_data)));
+ free_thread_stack_later(th);
+ FSHOW((stderr,"/exiting thread %lu\n", thread_self()));
return result;
}
-#endif /* LISP_FEATURE_SB_THREAD */
-#define THREAD_STRUCT_SIZE (THREAD_CONTROL_STACK_SIZE + BINDING_STACK_SIZE + \
- ALIEN_STACK_SIZE + dynamic_values_bytes + \
- 32 * SIGSTKSZ)
+#endif /* LISP_FEATURE_SB_THREAD */
static void
free_thread_struct(struct thread *th)
th->binding_stack_pointer=th->binding_stack_start;
th->this=th;
th->os_thread=0;
- th->interrupt_fun=NIL;
- th->interrupt_fun_lock=0;
- th->state=STATE_STARTING;
+ th->state=STATE_RUNNING;
#ifdef LISP_FEATURE_STACK_GROWS_DOWNWARD_NOT_UPWARD
th->alien_stack_pointer=((void *)th->alien_stack_start
+ ALIEN_STACK_SIZE-N_WORD_BYTES);
return th;
}
-static void
-link_thread(struct thread *th,os_thread_t kid_tid)
-{
- if (all_threads) all_threads->prev=th;
- th->next=all_threads;
- th->prev=0;
- all_threads=th;
- /* note that th->os_thread is 0 at this time. We rely on
- * all_threads_lock to ensure that we don't have >1 thread with
- * os_thread=0 on the list at once
- */
- protect_control_stack_guard_page(th,1);
- /* child will not start until this is set */
- th->os_thread=kid_tid;
- FSHOW((stderr,"/created thread %lu\n",kid_tid));
-}
-
void create_initial_thread(lispobj initial_function) {
struct thread *th=create_thread_struct(initial_function);
- os_thread_t kid_tid=thread_self();
- if(th && kid_tid>0) {
- link_thread(th,kid_tid);
- initial_thread_trampoline(all_threads); /* no return */
+ if(th) {
+ initial_thread_trampoline(th); /* no return */
} else lose("can't create initial thread");
}
sigset_t newset,oldset;
boolean r=1;
sigemptyset(&newset);
- /* Blocking deferrable signals is enough, since gc_stop_the_world
- * waits until the child leaves STATE_STARTING. And why not let gc
- * proceed as soon as possible? */
+ /* Blocking deferrable signals is enough, no need to block
+ * SIG_STOP_FOR_GC because the child process is not linked onto
+ * all_threads until it's ready. */
sigaddset_deferrable(&newset);
thread_sigmask(SIG_BLOCK, &newset, &oldset);
return r;
}
-struct thread *create_thread(lispobj initial_function) {
+os_thread_t create_thread(lispobj initial_function) {
struct thread *th;
- os_thread_t kid_tid=0;
- boolean success;
+ os_thread_t kid_tid;
if(linux_no_threads_p) return 0;
th=create_thread_struct(initial_function);
if(th==0) return 0;
- /* we must not be interrupted here after a successful
- * create_os_thread, because the kid will be waiting for its
- * thread struct to be linked */
- GET_ALL_THREADS_LOCK("create_thread")
-
- success=create_os_thread(th,&kid_tid);
- if (success)
- link_thread(th,kid_tid);
- else
+ if (create_os_thread(th,&kid_tid)) {
+ return kid_tid;
+ } else {
free_thread_struct(th);
-
- RELEASE_ALL_THREADS_LOCK("create_thread")
-
- if (success)
- return th;
- else
return 0;
-}
-
-/* called from lisp from the thread object finalizer */
-void reap_dead_thread(struct thread *th)
-{
- if(th->state!=STATE_DEAD)
- lose("thread %p is not joinable, state=%d\n",th,th->state);
-#ifdef LISP_FEATURE_GENCGC
- {
- sigset_t newset,oldset;
- sigemptyset(&newset);
- sigaddset_blockable(&newset);
- thread_sigmask(SIG_BLOCK, &newset, &oldset);
- gc_alloc_update_page_tables(0, &th->alloc_region);
- thread_sigmask(SIG_SETMASK,&oldset,0);
}
-#endif
- GET_ALL_THREADS_LOCK("reap_dead_thread")
- FSHOW((stderr,"/reap_dead_thread: reaping %lu\n",th->os_thread));
- if(th->prev)
- th->prev->next=th->next;
- else all_threads=th->next;
- if(th->next)
- th->next->prev=th->prev;
- RELEASE_ALL_THREADS_LOCK("reap_dead_thread")
- if(th->tls_cookie>=0) arch_os_thread_cleanup(th);
- gc_assert(pthread_join(th->os_thread,NULL)==0);
- free_thread_struct(th);
}
/* Send the signo to os_thread, retry if the rt signal queue is
return r;
}
-int interrupt_thread(struct thread *th, lispobj function)
+int signal_interrupt_thread(os_thread_t os_thread)
{
- /* In clone_threads, if A and B both interrupt C at approximately
- * the same time, it does not matter: the second signal will be
- * masked until the handler has returned from the first one. In
- * pthreads though, we can't put the knowledge of what function to
- * call into the siginfo, so we have to store it in the
- * destination thread, and do it in such a way that A won't
- * clobber B's interrupt. Hence, this stupid linked list.
- *
- * This does depend on SIG_INTERRUPT_THREAD being queued (as POSIX
- * RT signals are): we need to keep interrupt_fun data for exactly
- * as many signals as are going to be received by the destination
- * thread.
- */
- lispobj c=alloc_cons(function,NIL);
- sigset_t newset,oldset;
- sigemptyset(&newset);
- /* interrupt_thread_handler locks this spinlock with blockables
- * blocked (it does so for the sake of
- * arrange_return_to_lisp_function), so we must also block them or
- * else SIG_STOP_FOR_GC and all_threads_lock will find a way to
- * deadlock. */
- sigaddset_blockable(&newset);
- thread_sigmask(SIG_BLOCK, &newset, &oldset);
- if (th == arch_os_get_current_thread())
- lose("cannot interrupt current thread");
- get_spinlock(&th->interrupt_fun_lock,
- (long)arch_os_get_current_thread());
- ((struct cons *)native_pointer(c))->cdr=th->interrupt_fun;
- th->interrupt_fun=c;
- release_spinlock(&th->interrupt_fun_lock);
- thread_sigmask(SIG_SETMASK,&oldset,0);
- /* Called from lisp with the thread object as a parameter. Thus,
- * the object cannot be garbage collected and consequently reaped
- * and joined. Because it's not joined, kill should work (even if
- * the thread has died/exited). */
- {
- int status=kill_thread_safely(th->os_thread,SIG_INTERRUPT_THREAD);
- if (status==0) {
- return 0;
- } else if (status==ESRCH) {
- /* This thread has exited. */
- th->interrupt_fun=NIL;
- errno=ESRCH;
- return -1;
- } else {
- lose("cannot send SIG_INTERRUPT_THREAD to thread=%lu: %d, %s",
- th->os_thread,status,strerror(status));
- }
+ int status = kill_thread_safely(os_thread, SIG_INTERRUPT_THREAD);
+ if (status == 0) {
+ return 0;
+ } else if (status == ESRCH) {
+ return -1;
+ } else {
+ lose("cannot send SIG_INTERRUPT_THREAD to thread=%lu: %d, %s",
+ os_thread, status, strerror(status));
}
}
th->os_thread));
/* stop all other threads by sending them SIG_STOP_FOR_GC */
for(p=all_threads; p; p=p->next) {
- while(p->state==STATE_STARTING) sched_yield();
- if((p!=th) && (p->state==STATE_RUNNING)) {
+ if((p!=th) && ((p->state==STATE_RUNNING))) {
FSHOW_SIGNAL((stderr,"/gc_stop_the_world: suspending %lu\n",
p->os_thread));
status=kill_thread_safely(p->os_thread,SIG_STOP_FOR_GC);
/* wait for the running threads to stop or finish */
for(p=all_threads;p;) {
gc_assert(p->os_thread!=0);
- gc_assert(p->state!=STATE_STARTING);
if((p==th) || (p->state==STATE_SUSPENDED) ||
(p->state==STATE_DEAD)) {
p=p->next;
projects / sbcl.git / blobdiff