cpython/Python/thread.c

502 lines
12 KiB
C

/***********************************************************
Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
Amsterdam, The Netherlands.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior permission.
STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
******************************************************************/
#include "thread.h"
#ifdef DEBUG
static int thread_debug = 0;
#define dprintf(args) (thread_debug && printf args)
#else
#define dprintf(args)
#endif
#ifdef __sgi
#include <stdlib.h>
#include <stdio.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/prctl.h>
#include <ulocks.h>
#include <errno.h>
#define HDR_SIZE 2680 /* sizeof(ushdr_t) */
#define MAXPROC 100 /* max # of threads that can be started */
static usptr_t *shared_arena;
static ulock_t count_lock; /* protection for some variables */
static ulock_t wait_lock; /* lock used to wait for other threads */
static int waiting_for_threads; /* protected by count_lock */
static int nthreads; /* protected by count_lock */
static int exit_status;
static int do_exit; /* indicates that the program is to exit */
static int exiting; /* we're already exiting (for maybe_exit) */
static pid_t my_pid; /* PID of main thread */
static pid_t pidlist[MAXPROC]; /* PIDs of other threads */
static int maxpidindex; /* # of PIDs in pidlist */
#endif
#ifdef sun
#include <lwp/lwp.h>
#include <lwp/stackdep.h>
#define STACKSIZE 1000 /* stacksize for a thread */
#define NSTACKS 2 /* # stacks to be put in cache initialy */
struct lock {
int lock_locked;
cv_t lock_condvar;
mon_t lock_monitor;
};
#endif
#ifdef C_THREADS
#include <cthreads.h>
#endif
#ifdef __STDC__
#define _P(args) args
#define _P0() (void)
#define _P1(v,t) (t)
#define _P2(v1,t1,v2,t2) (t1,t2)
#else
#define _P(args) ()
#define _P0() ()
#define _P1(v,t) (v) t;
#define _P2(v1,t1,v2,t2) (v1,v2) t1; t2;
#endif
static int initialized;
#ifdef __sgi
/*
* This routine is called as a signal handler when another thread
* exits. When that happens, we must see whether we have to exit as
* well (because of an exit_prog()) or whether we should continue on.
*/
static void exit_sig _P0()
{
dprintf(("exit_sig called\n"));
if (exiting && getpid() == my_pid) {
dprintf(("already exiting\n"));
return;
}
if (do_exit) {
dprintf(("exiting in exit_sig\n"));
exit_thread();
}
}
/*
* This routine is called when a process calls exit(). If that wasn't
* done from the library, we do as if an exit_prog() was intended.
*/
static void maybe_exit _P0()
{
dprintf(("maybe_exit called\n"));
if (exiting) {
dprintf(("already exiting\n"));
return;
}
exit_prog(0);
}
#endif
/*
* Initialization.
*/
void init_thread _P0()
{
#ifdef __sgi
struct sigaction s;
#ifdef USE_DL
long addr, size;
#endif
#endif
#ifdef DEBUG
thread_debug = getenv("THREADDEBUG") != 0;
#endif
if (initialized)
return;
initialized = 1;
dprintf(("init_thread called\n"));
#ifdef __sgi
#ifdef USE_DL
if ((size = usconfig(CONF_INITSIZE, 64*1024)) < 0)
perror("usconfig - CONF_INITSIZE (check)");
if (usconfig(CONF_INITSIZE, size) < 0)
perror("usconfig - CONF_INITSIZE (reset)");
addr = (long) dl_getrange(size + HDR_SIZE);
dprintf(("trying to use addr %lx-%lx for shared arena\n", addr, addr+size));
errno = 0;
if ((addr = usconfig(CONF_ATTACHADDR, addr)) < 0 && errno != 0)
perror("usconfig - CONF_ATTACHADDR (set)");
#endif
if (usconfig(CONF_INITUSERS, 16) < 0)
perror("usconfig - CONF_INITUSERS");
my_pid = getpid(); /* so that we know which is the main thread */
atexit(maybe_exit);
s.sa_handler = exit_sig;
sigemptyset(&s.sa_mask);
/*sigaddset(&s.sa_mask, SIGUSR1);*/
s.sa_flags = 0;
sigaction(SIGUSR1, &s, 0);
if (prctl(PR_SETEXITSIG, SIGUSR1) < 0)
perror("prctl - PR_SETEXITSIG");
if (usconfig(CONF_ARENATYPE, US_SHAREDONLY) < 0)
perror("usconfig - CONF_ARENATYPE");
/*usconfig(CONF_LOCKTYPE, US_DEBUGPLUS);*/
if ((shared_arena = usinit(tmpnam(0))) == 0)
perror("usinit");
#ifdef USE_DL
if (usconfig(CONF_ATTACHADDR, addr) < 0) /* reset address */
perror("usconfig - CONF_ATTACHADDR (reset)");
#endif
if ((count_lock = usnewlock(shared_arena)) == NULL)
perror("usnewlock (count_lock)");
(void) usinitlock(count_lock);
if ((wait_lock = usnewlock(shared_arena)) == NULL)
perror("usnewlock (wait_lock)");
dprintf(("arena start: %lx, arena size: %ld\n", (long) shared_arena, (long) usconfig(CONF_GETSIZE, shared_arena)));
#endif
#ifdef sun
lwp_setstkcache(STACKSIZE, NSTACKS);
#endif
#ifdef C_THREADS
cthread_init();
#endif
}
/*
* Thread support.
*/
int start_new_thread _P2(func, void (*func) _P((void *)), arg, void *arg)
{
#ifdef sun
thread_t tid;
#endif
#if defined(__sgi) && defined(USE_DL)
long addr, size;
static int local_initialized = 0;
#endif
int success = 0; /* init not needed when SOLARIS and */
/* C_THREADS implemented properly */
dprintf(("start_new_thread called\n"));
if (!initialized)
init_thread();
#ifdef __sgi
switch (ussetlock(count_lock)) {
case 0: return 0;
case -1: perror("ussetlock (count_lock)");
}
if (maxpidindex >= MAXPROC)
success = -1;
else {
#ifdef USE_DL
if (!local_initialized) {
if ((size = usconfig(CONF_INITSIZE, 64*1024)) < 0)
perror("usconfig - CONF_INITSIZE (check)");
if (usconfig(CONF_INITSIZE, size) < 0)
perror("usconfig - CONF_INITSIZE (reset)");
addr = (long) dl_getrange(size + HDR_SIZE);
dprintf(("trying to use addr %lx-%lx for sproc\n", addr, addr+size));
errno = 0;
if ((addr = usconfig(CONF_ATTACHADDR, addr)) < 0 && errno != 0)
perror("usconfig - CONF_ATTACHADDR (set)");
}
#endif
if ((success = sproc(func, PR_SALL, arg)) < 0)
perror("sproc");
#ifdef USE_DL
if (!local_initialized) {
if (usconfig(CONF_ATTACHADDR, addr) < 0) /* reset address */
perror("usconfig - CONF_ATTACHADDR (reset)");
local_initialized = 1;
}
#endif
if (success >= 0) {
nthreads++;
pidlist[maxpidindex++] = success;
}
}
if (usunsetlock(count_lock) < 0)
perror("usunsetlock (count_lock)");
#endif
#ifdef SOLARIS
(void) thread_create(0, 0, func, arg, THREAD_NEW_LWP);
#endif
#ifdef sun
success = lwp_create(&tid, func, MINPRIO, 0, lwp_newstk(), 1, arg);
#endif
#ifdef C_THREADS
(void) cthread_fork(func, arg);
#endif
return success < 0 ? 0 : 1;
}
static void do_exit_thread _P1(no_cleanup, int no_cleanup)
{
dprintf(("exit_thread called\n"));
if (!initialized)
if (no_cleanup)
_exit(0);
else
exit(0);
#ifdef __sgi
if (ussetlock(count_lock) < 0)
perror("ussetlock (count_lock)");
nthreads--;
if (getpid() == my_pid) {
/* main thread; wait for other threads to exit */
exiting = 1;
if (do_exit) {
int i;
/* notify other threads */
if (nthreads >= 0) {
dprintf(("kill other threads\n"));
for (i = 0; i < maxpidindex; i++)
(void) kill(pidlist[i], SIGKILL);
_exit(exit_status);
}
}
waiting_for_threads = 1;
if (ussetlock(wait_lock) < 0)
perror("ussetlock (wait_lock)");
for (;;) {
if (nthreads < 0) {
dprintf(("really exit (%d)\n", exit_status));
if (no_cleanup)
_exit(exit_status);
else
exit(exit_status);
}
if (usunsetlock(count_lock) < 0)
perror("usunsetlock (count_lock)");
dprintf(("waiting for other threads (%d)\n", nthreads));
if (ussetlock(wait_lock) < 0)
perror("ussetlock (wait_lock)");
if (ussetlock(count_lock) < 0)
perror("ussetlock (count_lock)");
}
}
/* not the main thread */
if (waiting_for_threads) {
dprintf(("main thread is waiting\n"));
if (usunsetlock(wait_lock) < 0)
perror("usunsetlock (wait_lock)");
} else if (do_exit)
(void) kill(my_pid, SIGUSR1);
if (usunsetlock(count_lock) < 0)
perror("usunsetlock (count_lock)");
_exit(0);
#endif
#ifdef SOLARIS
thread_exit();
#endif
#ifdef sun
lwp_destroy(SELF);
#endif
#ifdef C_THREADS
cthread_exit(0);
#endif
}
void exit_thread _P0()
{
do_exit_thread(0);
}
void _exit_thread _P0()
{
do_exit_thread(1);
}
static void do_exit_prog _P2(status, int status, no_cleanup, int no_cleanup)
{
dprintf(("exit_prog(%d) called\n", status));
if (!initialized)
if (no_cleanup)
_exit(status);
else
exit(status);
#ifdef __sgi
do_exit = 1;
exit_status = status;
do_exit_thread(no_cleanup);
#endif
#ifdef sun
pod_exit(status);
#endif
}
void exit_prog _P1(status, int status)
{
do_exit_prog(status, 0);
}
void _exit_prog _P1(status, int status)
{
do_exit_prog(status, 1);
}
/*
* Lock support.
*/
type_lock allocate_lock _P0()
{
#ifdef __sgi
ulock_t lock;
#endif
#ifdef sun
struct lock *lock;
extern char *malloc();
#endif
dprintf(("allocate_lock called\n"));
if (!initialized)
init_thread();
#ifdef __sgi
if ((lock = usnewlock(shared_arena)) == NULL)
perror("usnewlock");
(void) usinitlock(lock);
#endif
#ifdef sun
lock = (struct lock *) malloc(sizeof(struct lock));
lock->lock_locked = 0;
(void) mon_create(&lock->lock_monitor);
(void) cv_create(&lock->lock_condvar, lock->lock_monitor);
#endif
dprintf(("allocate_lock() -> %lx\n", (long)lock));
return (type_lock) lock;
}
void free_lock _P1(lock, type_lock lock)
{
dprintf(("free_lock(%lx) called\n", (long)lock));
#ifdef __sgi
usfreelock((ulock_t) lock, shared_arena);
#endif
#ifdef sun
mon_destroy(((struct lock *) lock)->lock_monitor);
free((char *) lock);
#endif
}
int acquire_lock _P2(lock, type_lock lock, waitflag, int waitflag)
{
int success;
dprintf(("acquire_lock(%lx, %d) called\n", (long)lock, waitflag));
#ifdef __sgi
errno = 0; /* clear it just in case */
if (waitflag)
success = ussetlock((ulock_t) lock);
else
success = uscsetlock((ulock_t) lock, 1); /* Try it once */
if (success < 0)
perror(waitflag ? "ussetlock" : "uscsetlock");
#endif
#ifdef sun
success = 0;
(void) mon_enter(((struct lock *) lock)->lock_monitor);
if (waitflag)
while (((struct lock *) lock)->lock_locked)
cv_wait(((struct lock *) lock)->lock_condvar);
if (!((struct lock *) lock)->lock_locked) {
success = 1;
((struct lock *) lock)->lock_locked = 1;
}
cv_broadcast(((struct lock *) lock)->lock_condvar);
mon_exit(((struct lock *) lock)->lock_monitor);
#endif
dprintf(("acquire_lock(%lx, %d) -> %d\n", (long)lock, waitflag, success));
return success;
}
void release_lock _P1(lock, type_lock lock)
{
dprintf(("release_lock(%lx) called\n", (long)lock));
#ifdef __sgi
if (usunsetlock((ulock_t) lock) < 0)
perror("usunsetlock");
#endif
#ifdef sun
(void) mon_enter(((struct lock *) lock)->lock_monitor);
((struct lock *) lock)->lock_locked = 0;
cv_broadcast(((struct lock *) lock)->lock_condvar);
mon_exit(((struct lock *) lock)->lock_monitor);
#endif
}
/*
* Semaphore support.
*/
type_sema allocate_sema _P1(value, int value)
{
#ifdef __sgi
usema_t *sema;
#endif
dprintf(("allocate_sema called\n"));
if (!initialized)
init_thread();
#ifdef __sgi
if ((sema = usnewsema(shared_arena, value)) == NULL)
perror("usnewsema");
dprintf(("allocate_sema() -> %lx\n", (long) sema));
return (type_sema) sema;
#endif
}
void free_sema _P1(sema, type_sema sema)
{
dprintf(("free_sema(%lx) called\n", (long) sema));
#ifdef __sgi
usfreesema((usema_t *) sema, shared_arena);
#endif
}
void down_sema _P1(sema, type_sema sema)
{
dprintf(("down_sema(%lx) called\n", (long) sema));
#ifdef __sgi
if (uspsema((usema_t *) sema) < 0)
perror("uspsema");
#endif
dprintf(("down_sema(%lx) return\n", (long) sema));
}
void up_sema _P1(sema, type_sema sema)
{
dprintf(("up_sema(%lx)\n", (long) sema));
#ifdef __sgi
if (usvsema((usema_t *) sema) < 0)
perror("usvsema");
#endif
}