#include <stdlib.h>
#include <stdio.h>
+#include <string.h>
#include <sched.h>
#include <signal.h>
#include <stddef.h>
#include <errno.h>
-#include "runtime.h"
+#include <sys/types.h>
+#include <sys/wait.h>
+
#include "sbcl.h"
+#include "runtime.h"
#include "validate.h" /* for CONTROL_STACK_SIZE etc */
+#include "alloc.h"
#include "thread.h"
#include "arch.h"
#include "target-arch-os.h"
#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");
+ if(th->os_thread < 1) lose("th->os_thread 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);
#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
- */
+#ifdef LISP_FEATURE_SB_THREAD
+void mark_thread_dead(struct thread *th) {
+ funcall1(SymbolFunction(HANDLE_THREAD_EXIT),alloc_number(th->os_thread));
+ /* I hope it's safe for a thread to detach itself inside a
+ * cancellation cleanup */
+ pthread_detach(th->os_thread);
+ th->state=STATE_DEAD;
+ /* FIXME: if gc hits here it will rip the stack from under us */
+}
+/* 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
+ * bookkeeping needs to be done
+ */
int
new_thread_trampoline(struct thread *th)
{
- lispobj function;
+ lispobj function,ret;
function = th->unbound_marker;
th->unbound_marker = UNBOUND_MARKER_WIDETAG;
+ pthread_cleanup_push((void (*) (void *))mark_thread_dead,th);
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();
+ while(th->os_thread<1) sched_yield();
th->state=STATE_RUNNING;
- return funcall0(function);
+ ret = funcall0(function);
+ /* execute cleanup */
+ pthread_cleanup_pop(1);
+ return ret;
}
+#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
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);
#endif
}
+ th=&per_thread->thread;
th->control_stack_start = spaces;
th->binding_stack_start=
(lispobj*)((void*)th->control_stack_start+THREAD_CONTROL_STACK_SIZE);
(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_STOPPED;
+ th->os_thread=0;
+ th->interrupt_fun=NIL;
+ th->interrupt_fun_lock=0;
+ 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
* 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;
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 = (struct interrupt_data *)
+ os_validate(0,(sizeof (struct interrupt_data)));
if(all_threads)
memcpy(th->interrupt_data,
arch_os_get_current_thread()->interrupt_data,
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)
+void link_thread(struct thread *th,os_thread_t kid_tid)
{
- get_spinlock(&all_threads_lock,kid_pid);
+ sigset_t newset,oldset;
+ sigemptyset(&newset);
+ sigaddset_blockable(&newset);
+ thread_sigmask(SIG_BLOCK, &newset, &oldset);
+
+ get_spinlock(&all_threads_lock,kid_tid);
+ if (all_threads) all_threads->prev=th;
th->next=all_threads;
+ th->prev=0;
all_threads=th;
- /* note that th->pid is 0 at this time. We rely on all_threads_lock
- * to ensure that we don't have >1 thread with pid=0 on the list at once
+ /* 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->pid,1);
+ protect_control_stack_guard_page(th->os_thread,1);
+ /* child will not start until this is set */
+ th->os_thread=kid_tid;
release_spinlock(&all_threads_lock);
- th->pid=kid_pid; /* child will not start until this is set */
+
+ thread_sigmask(SIG_SETMASK,&oldset,0);
}
-pid_t create_initial_thread(lispobj initial_function) {
+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);
+ os_thread_t kid_tid=thread_self();
+ if(th && kid_tid>0) {
+ link_thread(th,kid_tid);
initial_thread_trampoline(all_threads); /* no return */
} else lose("can't create initial thread");
}
-#ifdef LISP_FEATURE_LINUX
-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;
+#ifdef LISP_FEATURE_SB_THREAD
+os_thread_t create_thread(lispobj initial_function) {
+ struct thread *th;
+ os_thread_t kid_tid=0;
+ pthread_attr_t attr;
+
+ 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()->os_thread);
+#ifdef QSHOW_SIGNALS
+ SHOW("create_thread:got lock");
+#endif
+ /* The new thread inherits the restrictive signal mask set here,
+ * and enables signals again when it is set up properly. */
+ {
+ sigset_t newset,oldset;
+ sigemptyset(&newset);
+ sigaddset_blockable(&newset);
+ thread_sigmask(SIG_BLOCK, &newset, &oldset);
+ if((pthread_attr_init(&attr)) ||
+ (pthread_attr_setstack(&attr,th->control_stack_start,
+ THREAD_CONTROL_STACK_SIZE-16)) ||
+ (pthread_create
+ (&kid_tid,&attr,(void *(*)(void *))new_thread_trampoline,th)))
+ kid_tid=0;
+ thread_sigmask(SIG_SETMASK,&oldset,0);
}
-}
+ if(kid_tid>0) {
+ link_thread(th,kid_tid);
+ /* it's started and initialized, it's safe to gc */
+ release_spinlock(&thread_start_lock);
+#ifdef QSHOW_SIGNALS
+ SHOW("create_thread:released lock");
#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);
+ /* by now the kid might have already exited */
+ return kid_tid;
+ } else {
+ release_spinlock(&thread_start_lock);
+#ifdef QSHOW_SIGNALS
+ SHOW("create_thread:released lock(failure)");
#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 */
+ 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;
}
- 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);
}
+#endif
-
-struct thread *find_thread_by_pid(pid_t pid)
+struct thread *find_thread_by_os_thread(os_thread_t tid)
{
struct thread *th;
for_each_thread(th)
- if(th->pid==pid) return th;
+ if(th->os_thread==tid) return th;
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
- * "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);
-}
-
-void unblock_sigcont_and_sleep(void)
-{
- sigset_t set;
- sigemptyset(&set);
- sigaddset(&set,SIG_DEQUEUE);
- do {
- errno=0;
- sigwaitinfo(&set,0);
- }while(errno==EINTR);
- sigprocmask(SIG_UNBLOCK,&set,0);
-}
+/* This is not needed unless #+SB-THREAD, as there's a trivial null
+ * unithread definition. */
-int interrupt_thread(pid_t pid, lispobj function)
+void reap_dead_threads()
{
- union sigval sigval;
- sigval.sival_int=function;
-
- return sigqueue(pid, SIG_INTERRUPT_THREAD, sigval);
+ struct thread *th,*next,*prev=0;
+ th=all_threads;
+ while(th) {
+ next=th->next;
+ if(th->state==STATE_DEAD) {
+#ifdef LISP_FEATURE_GENCGC
+ gc_alloc_update_page_tables(0, &th->alloc_region);
+#endif
+ get_spinlock(&all_threads_lock,th->os_thread);
+ 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 signal_thread_to_dequeue (pid_t pid)
+int interrupt_thread(os_thread_t tid, lispobj function)
{
- return kill (pid, SIG_DEQUEUE);
+ struct thread *th;
+ for_each_thread(th)
+ if((th->os_thread==tid) && (th->state != STATE_DEAD)) {
+ /* 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.
+ */
+ struct cons *c;
+ int kill_status;
+ /* mask the signals in case this thread is being interrupted */
+ sigset_t newset,oldset;
+ sigemptyset(&newset);
+ sigaddset_blockable(&newset);
+ thread_sigmask(SIG_BLOCK, &newset, &oldset);
+
+ get_spinlock(&th->interrupt_fun_lock,
+ (int)arch_os_get_current_thread());
+ kill_status=thread_kill(th->os_thread,SIG_INTERRUPT_THREAD);
+ if(kill_status==0) {
+ c=alloc_cons(function,th->interrupt_fun);
+ th->interrupt_fun=c;
+ }
+ release_spinlock(&th->interrupt_fun_lock);
+ thread_sigmask(SIG_SETMASK,&oldset,0);
+ return (kill_status ? -1 : 0);
+ }
+ errno=EPERM; return -1;
}
-
/* 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 */
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);
+#ifdef QSHOW_SIGNALS
+ SHOW("gc_stop_the_world:begin");
+#endif
+ /* keep threads from starting while the world is stopped. */
+ get_spinlock(&thread_start_lock,th->os_thread);
+#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) {
+ while(p->state==STATE_STARTING) sched_yield();
+ if((p!=th) && (p->os_thread!=0) && (p->state==STATE_RUNNING)) {
+ p->state=STATE_STOPPING;
+ if(thread_kill(p->os_thread,SIG_STOP_FOR_GC)==-1) {
+ /* FIXME: we can't kill the thread; assume because it died
+ * already */
+ 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->os_thread==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->os_thread!=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));
+ }
+ thread_kill(p->os_thread,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->os_thread==0) || (p->state!=STATE_STOPPED)) {
+ p=p->next;
+ }
+ }
+ release_spinlock(&thread_start_lock);
+#ifdef QSHOW_SIGNALS
+ SHOW("gc_start_the_world:end");
+#endif
}
#endif
projects / sbcl.git / blobdiff