#include <stdlib.h>
#include <stdio.h>
+#include <string.h>
#include <sched.h>
#include <signal.h>
#include <stddef.h>
#include <errno.h>
-#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 */
#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 */
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;
-
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
}
/* this is called from any other thread to create the new one, and
* 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
th->binding_stack_pointer=th->binding_stack_start;
th->this=th;
th->pid=0;
- th->state=STATE_RUNNING;
+ 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 */
#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);
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;
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_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;
+ }
}
+#endif
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);
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);
}
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);
}