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-rw-r--r--aix_irix_threads.c865
1 files changed, 865 insertions, 0 deletions
diff --git a/aix_irix_threads.c b/aix_irix_threads.c
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+++ b/aix_irix_threads.c
@@ -0,0 +1,865 @@
+/*
+ * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
+ * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
+ * Copyright (c) 1999-2003 by Hewlett-Packard Company. All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ */
+/*
+ * Support code for Irix (>=6.2) Pthreads and for AIX pthreads.
+ * This relies on properties
+ * not guaranteed by the Pthread standard. It may or may not be portable
+ * to other implementations.
+ *
+ * Note that there is a lot of code duplication between this file and
+ * (pthread_support.c, pthread_stop_world.c). They should be merged.
+ * Pthread_support.c should be directly usable.
+ *
+ * Please avoid adding new ports here; use the generic pthread support
+ * as a base instead.
+ */
+
+# if defined(GC_IRIX_THREADS) || defined(GC_AIX_THREADS)
+
+# include "private/gc_priv.h"
+# include <pthread.h>
+# include <assert.h>
+# include <semaphore.h>
+# include <time.h>
+# include <errno.h>
+# include <unistd.h>
+# include <sys/mman.h>
+# include <sys/time.h>
+
+#undef pthread_create
+#undef pthread_sigmask
+#undef pthread_join
+
+#if defined(GC_IRIX_THREADS) && !defined(MUTEX_RECURSIVE_NP)
+#define MUTEX_RECURSIVE_NP PTHREAD_MUTEX_RECURSIVE
+#endif
+
+void GC_thr_init();
+
+#if 0
+void GC_print_sig_mask()
+{
+ sigset_t blocked;
+ int i;
+
+ if (pthread_sigmask(SIG_BLOCK, NULL, &blocked) != 0)
+ ABORT("pthread_sigmask");
+ GC_printf0("Blocked: ");
+ for (i = 1; i <= MAXSIG; i++) {
+ if (sigismember(&blocked, i)) { GC_printf1("%ld ",(long) i); }
+ }
+ GC_printf0("\n");
+}
+#endif
+
+/* We use the allocation lock to protect thread-related data structures. */
+
+/* The set of all known threads. We intercept thread creation and */
+/* joins. We never actually create detached threads. We allocate all */
+/* new thread stacks ourselves. These allow us to maintain this */
+/* data structure. */
+/* Protected by GC_thr_lock. */
+/* Some of this should be declared volatile, but that's incosnsistent */
+/* with some library routine declarations. */
+typedef struct GC_Thread_Rep {
+ struct GC_Thread_Rep * next; /* More recently allocated threads */
+ /* with a given pthread id come */
+ /* first. (All but the first are */
+ /* guaranteed to be dead, but we may */
+ /* not yet have registered the join.) */
+ pthread_t id;
+ word stop;
+# define NOT_STOPPED 0
+# define PLEASE_STOP 1
+# define STOPPED 2
+ word flags;
+# define FINISHED 1 /* Thread has exited. */
+# define DETACHED 2 /* Thread is intended to be detached. */
+# define CLIENT_OWNS_STACK 4
+ /* Stack was supplied by client. */
+ ptr_t stack;
+ ptr_t stack_ptr; /* Valid only when stopped. */
+ /* But must be within stack region at */
+ /* all times. */
+ size_t stack_size; /* 0 for original thread. */
+ void * status; /* Used only to avoid premature */
+ /* reclamation of any data it might */
+ /* reference. */
+} * GC_thread;
+
+GC_thread GC_lookup_thread(pthread_t id);
+
+/*
+ * The only way to suspend threads given the pthread interface is to send
+ * signals. Unfortunately, this means we have to reserve
+ * a signal, and intercept client calls to change the signal mask.
+ */
+#if 0 /* DOB: 6.1 */
+# if defined(GC_AIX_THREADS)
+# define SIG_SUSPEND SIGUSR1
+# else
+# define SIG_SUSPEND (SIGRTMIN + 6)
+# endif
+#endif
+
+pthread_mutex_t GC_suspend_lock = PTHREAD_MUTEX_INITIALIZER;
+ /* Number of threads stopped so far */
+pthread_cond_t GC_suspend_ack_cv = PTHREAD_COND_INITIALIZER;
+pthread_cond_t GC_continue_cv = PTHREAD_COND_INITIALIZER;
+
+void GC_suspend_handler(int sig)
+{
+ int dummy;
+ GC_thread me;
+ sigset_t all_sigs;
+ sigset_t old_sigs;
+ int i;
+
+ if (sig != SIG_SUSPEND) ABORT("Bad signal in suspend_handler");
+ me = GC_lookup_thread(pthread_self());
+ /* The lookup here is safe, since I'm doing this on behalf */
+ /* of a thread which holds the allocation lock in order */
+ /* to stop the world. Thus concurrent modification of the */
+ /* data structure is impossible. */
+ if (PLEASE_STOP != me -> stop) {
+ /* Misdirected signal. */
+ pthread_mutex_unlock(&GC_suspend_lock);
+ return;
+ }
+ pthread_mutex_lock(&GC_suspend_lock);
+ me -> stack_ptr = (ptr_t)(&dummy);
+ me -> stop = STOPPED;
+ pthread_cond_signal(&GC_suspend_ack_cv);
+ pthread_cond_wait(&GC_continue_cv, &GC_suspend_lock);
+ pthread_mutex_unlock(&GC_suspend_lock);
+ /* GC_printf1("Continuing 0x%x\n", pthread_self()); */
+}
+
+
+GC_bool GC_thr_initialized = FALSE;
+
+size_t GC_min_stack_sz;
+
+size_t GC_page_sz;
+
+# define N_FREE_LISTS 25
+ptr_t GC_stack_free_lists[N_FREE_LISTS] = { 0 };
+ /* GC_stack_free_lists[i] is free list for stacks of */
+ /* size GC_min_stack_sz*2**i. */
+ /* Free lists are linked through first word. */
+
+/* Return a stack of size at least *stack_size. *stack_size is */
+/* replaced by the actual stack size. */
+/* Caller holds allocation lock. */
+ptr_t GC_stack_alloc(size_t * stack_size)
+{
+ register size_t requested_sz = *stack_size;
+ register size_t search_sz = GC_min_stack_sz;
+ register int index = 0; /* = log2(search_sz/GC_min_stack_sz) */
+ register ptr_t result;
+
+ while (search_sz < requested_sz) {
+ search_sz *= 2;
+ index++;
+ }
+ if ((result = GC_stack_free_lists[index]) == 0
+ && (result = GC_stack_free_lists[index+1]) != 0) {
+ /* Try next size up. */
+ search_sz *= 2; index++;
+ }
+ if (result != 0) {
+ GC_stack_free_lists[index] = *(ptr_t *)result;
+ } else {
+ result = (ptr_t) GC_scratch_alloc(search_sz + 2*GC_page_sz);
+ result = (ptr_t)(((word)result + GC_page_sz) & ~(GC_page_sz - 1));
+ /* Protect hottest page to detect overflow. */
+# ifdef STACK_GROWS_UP
+ /* mprotect(result + search_sz, GC_page_sz, PROT_NONE); */
+# else
+ /* mprotect(result, GC_page_sz, PROT_NONE); */
+ result += GC_page_sz;
+# endif
+ }
+ *stack_size = search_sz;
+ return(result);
+}
+
+/* Caller holds allocation lock. */
+void GC_stack_free(ptr_t stack, size_t size)
+{
+ register int index = 0;
+ register size_t search_sz = GC_min_stack_sz;
+
+ while (search_sz < size) {
+ search_sz *= 2;
+ index++;
+ }
+ if (search_sz != size) ABORT("Bad stack size");
+ *(ptr_t *)stack = GC_stack_free_lists[index];
+ GC_stack_free_lists[index] = stack;
+}
+
+
+
+# define THREAD_TABLE_SZ 128 /* Must be power of 2 */
+volatile GC_thread GC_threads[THREAD_TABLE_SZ];
+
+void GC_push_thread_structures GC_PROTO((void))
+{
+ GC_push_all((ptr_t)(GC_threads), (ptr_t)(GC_threads)+sizeof(GC_threads));
+}
+
+/* Add a thread to GC_threads. We assume it wasn't already there. */
+/* Caller holds allocation lock. */
+GC_thread GC_new_thread(pthread_t id)
+{
+ int hv = ((word)id) % THREAD_TABLE_SZ;
+ GC_thread result;
+ static struct GC_Thread_Rep first_thread;
+ static GC_bool first_thread_used = FALSE;
+
+ if (!first_thread_used) {
+ result = &first_thread;
+ first_thread_used = TRUE;
+ /* Dont acquire allocation lock, since we may already hold it. */
+ } else {
+ result = (struct GC_Thread_Rep *)
+ GC_generic_malloc_inner(sizeof(struct GC_Thread_Rep), NORMAL);
+ }
+ if (result == 0) return(0);
+ result -> id = id;
+ result -> next = GC_threads[hv];
+ GC_threads[hv] = result;
+ /* result -> flags = 0; */
+ /* result -> stop = 0; */
+ return(result);
+}
+
+/* Delete a thread from GC_threads. We assume it is there. */
+/* (The code intentionally traps if it wasn't.) */
+/* Caller holds allocation lock. */
+void GC_delete_thread(pthread_t id)
+{
+ int hv = ((word)id) % THREAD_TABLE_SZ;
+ register GC_thread p = GC_threads[hv];
+ register GC_thread prev = 0;
+
+ while (!pthread_equal(p -> id, id)) {
+ prev = p;
+ p = p -> next;
+ }
+ if (prev == 0) {
+ GC_threads[hv] = p -> next;
+ } else {
+ prev -> next = p -> next;
+ }
+}
+
+/* If a thread has been joined, but we have not yet */
+/* been notified, then there may be more than one thread */
+/* in the table with the same pthread id. */
+/* This is OK, but we need a way to delete a specific one. */
+void GC_delete_gc_thread(pthread_t id, GC_thread gc_id)
+{
+ int hv = ((word)id) % THREAD_TABLE_SZ;
+ register GC_thread p = GC_threads[hv];
+ register GC_thread prev = 0;
+
+ while (p != gc_id) {
+ prev = p;
+ p = p -> next;
+ }
+ if (prev == 0) {
+ GC_threads[hv] = p -> next;
+ } else {
+ prev -> next = p -> next;
+ }
+}
+
+/* Return a GC_thread corresponding to a given thread_t. */
+/* Returns 0 if it's not there. */
+/* Caller holds allocation lock or otherwise inhibits */
+/* updates. */
+/* If there is more than one thread with the given id we */
+/* return the most recent one. */
+GC_thread GC_lookup_thread(pthread_t id)
+{
+ int hv = ((word)id) % THREAD_TABLE_SZ;
+ register GC_thread p = GC_threads[hv];
+
+ while (p != 0 && !pthread_equal(p -> id, id)) p = p -> next;
+ return(p);
+}
+
+#if defined(GC_AIX_THREADS)
+void GC_stop_world()
+{
+ pthread_t my_thread = pthread_self();
+ register int i;
+ register GC_thread p;
+ register int result;
+ struct timespec timeout;
+
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ if (p -> id != my_thread) {
+ pthread_suspend_np(p->id);
+ }
+ }
+ }
+ /* GC_printf1("World stopped 0x%x\n", pthread_self()); */
+}
+
+void GC_start_world()
+{
+ GC_thread p;
+ unsigned i;
+ pthread_t my_thread = pthread_self();
+
+ /* GC_printf0("World starting\n"); */
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ if (p -> id != my_thread) {
+ pthread_continue_np(p->id);
+ }
+ }
+ }
+}
+
+#else /* GC_AIX_THREADS */
+
+/* Caller holds allocation lock. */
+void GC_stop_world()
+{
+ pthread_t my_thread = pthread_self();
+ register int i;
+ register GC_thread p;
+ register int result;
+ struct timespec timeout;
+
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ if (p -> id != my_thread) {
+ if (p -> flags & FINISHED) {
+ p -> stop = STOPPED;
+ continue;
+ }
+ p -> stop = PLEASE_STOP;
+ result = pthread_kill(p -> id, SIG_SUSPEND);
+ /* GC_printf1("Sent signal to 0x%x\n", p -> id); */
+ switch(result) {
+ case ESRCH:
+ /* Not really there anymore. Possible? */
+ p -> stop = STOPPED;
+ break;
+ case 0:
+ break;
+ default:
+ ABORT("pthread_kill failed");
+ }
+ }
+ }
+ }
+ pthread_mutex_lock(&GC_suspend_lock);
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ while (p -> id != my_thread && p -> stop != STOPPED) {
+ clock_gettime(CLOCK_REALTIME, &timeout);
+ timeout.tv_nsec += 50000000; /* 50 msecs */
+ if (timeout.tv_nsec >= 1000000000) {
+ timeout.tv_nsec -= 1000000000;
+ ++timeout.tv_sec;
+ }
+ result = pthread_cond_timedwait(&GC_suspend_ack_cv,
+ &GC_suspend_lock,
+ &timeout);
+ if (result == ETIMEDOUT) {
+ /* Signal was lost or misdirected. Try again. */
+ /* Duplicate signals should be benign. */
+ result = pthread_kill(p -> id, SIG_SUSPEND);
+ }
+ }
+ }
+ }
+ pthread_mutex_unlock(&GC_suspend_lock);
+ /* GC_printf1("World stopped 0x%x\n", pthread_self()); */
+}
+
+/* Caller holds allocation lock. */
+void GC_start_world()
+{
+ GC_thread p;
+ unsigned i;
+
+ /* GC_printf0("World starting\n"); */
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ p -> stop = NOT_STOPPED;
+ }
+ }
+ pthread_mutex_lock(&GC_suspend_lock);
+ /* All other threads are at pthread_cond_wait in signal handler. */
+ /* Otherwise we couldn't have acquired the lock. */
+ pthread_mutex_unlock(&GC_suspend_lock);
+ pthread_cond_broadcast(&GC_continue_cv);
+}
+
+#endif /* GC_AIX_THREADS */
+
+# ifdef MMAP_STACKS
+--> not really supported yet.
+int GC_is_thread_stack(ptr_t addr)
+{
+ register int i;
+ register GC_thread p;
+
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ if (p -> stack_size != 0) {
+ if (p -> stack <= addr &&
+ addr < p -> stack + p -> stack_size)
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+# endif
+
+/* We hold allocation lock. Should do exactly the right thing if the */
+/* world is stopped. Should not fail if it isn't. */
+void GC_push_all_stacks()
+{
+ register int i;
+ register GC_thread p;
+ register ptr_t sp = GC_approx_sp();
+ register ptr_t hot, cold;
+ pthread_t me = pthread_self();
+
+ if (!GC_thr_initialized) GC_thr_init();
+ /* GC_printf1("Pushing stacks from thread 0x%x\n", me); */
+ for (i = 0; i < THREAD_TABLE_SZ; i++) {
+ for (p = GC_threads[i]; p != 0; p = p -> next) {
+ if (p -> flags & FINISHED) continue;
+ if (pthread_equal(p -> id, me)) {
+ hot = GC_approx_sp();
+ } else {
+#ifdef GC_AIX_THREADS
+ /* AIX doesn't use signals to suspend, so we need to get an accurate hot stack pointer */
+ pthread_t id = p -> id;
+ struct __pthrdsinfo pinfo;
+ int val = 255;
+ char regbuf[255];
+ int retval = pthread_getthrds_np(&id, PTHRDSINFO_QUERY_ALL, &pinfo, sizeof(pinfo), regbuf, &val);
+ if (retval != 0) { printf("ERROR: pthread_getthrds_np() failed in GC\n"); abort(); }
+ hot = (ptr_t)(unsigned long)pinfo.__pi_ustk;
+ if ((p -> stack_size != 0 &&
+ (pinfo.__pi_stackend != ((ptr_t)p -> stack) + p -> stack_size ||
+ p -> stack_ptr < p -> stack ||
+ p -> stack_ptr > ((ptr_t)p -> stack) + p -> stack_size))) {
+ printf("ERROR in GC_push_all_stacks() stack state:\n"
+ "p->stack: 0x%08x\n"
+ "p->stack_size: 0x%08x\n"
+ "p->stack_ptr: 0x%08x\n"
+ "(p->stack+p->stack_size): 0x%08x\n"
+ "pinfo.__pi_stackaddr: 0x%08x\n"
+ "pinfo.__pi_stacksize: 0x%08x\n"
+ "pinfo.__pi_stackend: 0x%08x\n"
+ "GC_stackbottom: 0x%08x\n"
+ ,
+ (uintptr_t)p->stack, (uintptr_t)p->stack_size,
+ (uintptr_t)p->stack_ptr, (uintptr_t)(((ptr_t)(p->stack))+p->stack_size),
+ (uintptr_t)pinfo.__pi_stackaddr, (uintptr_t)pinfo.__pi_stacksize, (uintptr_t)pinfo.__pi_stackend,
+ (uintptr_t)GC_stackbottom
+ );
+ }
+ /* push the registers too, because they won't be on stack */
+ GC_push_all_eager((ptr_t)&pinfo.__pi_context, (ptr_t)((&pinfo.__pi_context)+1));
+ GC_push_all_eager((ptr_t)regbuf, (ptr_t)&regbuf[val]);
+#else
+ hot = p -> stack_ptr;
+#endif
+ }
+ if (p -> stack_size != 0) {
+# ifdef STACK_GROWS_UP
+ cold = p -> stack;
+# else
+ cold = p -> stack + p -> stack_size;
+# endif
+ } else {
+ /* The original stack. */
+ cold = GC_stackbottom;
+ }
+# ifdef STACK_GROWS_UP
+ GC_push_all_stack(cold, hot);
+# else
+ /* printf("thread 0x%x: hot=0x%08x cold=0x%08x\n", p -> id, hot, cold); */
+ GC_push_all_stack(hot, cold);
+# endif
+ }
+ }
+}
+
+
+/* We hold the allocation lock. */
+void GC_thr_init()
+{
+ GC_thread t;
+ struct sigaction act;
+
+ if (GC_thr_initialized) return;
+ GC_thr_initialized = TRUE;
+ GC_min_stack_sz = HBLKSIZE;
+ GC_page_sz = sysconf(_SC_PAGESIZE);
+#ifndef GC_AIX_THREADS
+ (void) sigaction(SIG_SUSPEND, 0, &act);
+ if (act.sa_handler != SIG_DFL)
+ ABORT("Previously installed SIG_SUSPEND handler");
+ /* Install handler. */
+ act.sa_handler = GC_suspend_handler;
+ act.sa_flags = SA_RESTART;
+ (void) sigemptyset(&act.sa_mask);
+ if (0 != sigaction(SIG_SUSPEND, &act, 0))
+ ABORT("Failed to install SIG_SUSPEND handler");
+#endif
+ /* Add the initial thread, so we can stop it. */
+ t = GC_new_thread(pthread_self());
+ t -> stack_size = 0;
+ t -> stack_ptr = (ptr_t)(&t);
+ t -> flags = DETACHED;
+}
+
+int GC_pthread_sigmask(int how, const sigset_t *set, sigset_t *oset)
+{
+ sigset_t fudged_set;
+
+#ifdef GC_AIX_THREADS
+ return(pthread_sigmask(how, set, oset));
+#endif
+
+ if (set != NULL && (how == SIG_BLOCK || how == SIG_SETMASK)) {
+ fudged_set = *set;
+ sigdelset(&fudged_set, SIG_SUSPEND);
+ set = &fudged_set;
+ }
+ return(pthread_sigmask(how, set, oset));
+}
+
+struct start_info {
+ void *(*start_routine)(void *);
+ void *arg;
+ word flags;
+ ptr_t stack;
+ size_t stack_size;
+ pthread_mutex_t registeredlock;
+ pthread_cond_t registered;
+ int volatile registereddone;
+};
+
+void GC_thread_exit_proc(void *arg)
+{
+ GC_thread me;
+
+ LOCK();
+ me = GC_lookup_thread(pthread_self());
+ if (me -> flags & DETACHED) {
+ GC_delete_thread(pthread_self());
+ } else {
+ me -> flags |= FINISHED;
+ }
+ UNLOCK();
+}
+
+int GC_pthread_join(pthread_t thread, void **retval)
+{
+ int result;
+ GC_thread thread_gc_id;
+
+ LOCK();
+ thread_gc_id = GC_lookup_thread(thread);
+ /* This is guaranteed to be the intended one, since the thread id */
+ /* cant have been recycled by pthreads. */
+ UNLOCK();
+ result = pthread_join(thread, retval);
+ /* Some versions of the Irix pthreads library can erroneously */
+ /* return EINTR when the call succeeds. */
+ if (EINTR == result) result = 0;
+ LOCK();
+ /* Here the pthread thread id may have been recycled. */
+ GC_delete_gc_thread(thread, thread_gc_id);
+ UNLOCK();
+ return result;
+}
+
+void * GC_start_routine(void * arg)
+{
+ struct start_info * si = arg;
+ void * result;
+ GC_thread me;
+ pthread_t my_pthread;
+ void *(*start)(void *);
+ void *start_arg;
+
+ my_pthread = pthread_self();
+ /* If a GC occurs before the thread is registered, that GC will */
+ /* ignore this thread. That's fine, since it will block trying to */
+ /* acquire the allocation lock, and won't yet hold interesting */
+ /* pointers. */
+ LOCK();
+ /* We register the thread here instead of in the parent, so that */
+ /* we don't need to hold the allocation lock during pthread_create. */
+ /* Holding the allocation lock there would make REDIRECT_MALLOC */
+ /* impossible. It probably still doesn't work, but we're a little */
+ /* closer ... */
+ /* This unfortunately means that we have to be careful the parent */
+ /* doesn't try to do a pthread_join before we're registered. */
+ me = GC_new_thread(my_pthread);
+ me -> flags = si -> flags;
+ me -> stack = si -> stack;
+ me -> stack_size = si -> stack_size;
+#ifdef STACK_GROWS_UP
+ me -> stack_ptr = (ptr_t)si -> stack + si -> stack_size - sizeof(word);
+#else
+ /* stack_ptr needs to point to the hot part of the stack (or conservatively, past it) */
+ me -> stack_ptr = (ptr_t)si -> stack;
+#endif
+ UNLOCK();
+ start = si -> start_routine;
+ start_arg = si -> arg;
+
+ pthread_mutex_lock(&(si->registeredlock));
+ si->registereddone = 1;
+ pthread_cond_signal(&(si->registered));
+ pthread_mutex_unlock(&(si->registeredlock));
+
+ pthread_cleanup_push(GC_thread_exit_proc, 0);
+ result = (*start)(start_arg);
+ me -> status = result;
+ pthread_cleanup_pop(1);
+ /* This involves acquiring the lock, ensuring that we can't exit */
+ /* while a collection that thinks we're alive is trying to stop */
+ /* us. */
+ return(result);
+}
+
+# if defined(GC_AIX_THREADS)
+ /* pthread_attr_t is not a structure, thus a simple structure copy */
+ /* won't work. */
+ static void copy_attr(pthread_attr_t * pa_ptr,
+ const pthread_attr_t * source) {
+ int tmp;
+ size_t stmp;
+ void * vtmp;
+ struct sched_param sp_tmp;
+#ifndef GC_AIX_THREADS
+ pthread_spu_t ps_tmp;
+#endif
+ (void) pthread_attr_init(pa_ptr);
+ (void) pthread_attr_getdetachstate(source, &tmp);
+ (void) pthread_attr_setdetachstate(pa_ptr, tmp);
+ (void) pthread_attr_getinheritsched(source, &tmp);
+ (void) pthread_attr_setinheritsched(pa_ptr, tmp);
+ (void) pthread_attr_getschedpolicy(source, &tmp);
+ (void) pthread_attr_setschedpolicy(pa_ptr, tmp);
+ (void) pthread_attr_getstacksize(source, &stmp);
+ (void) pthread_attr_setstacksize(pa_ptr, stmp);
+ (void) pthread_attr_getguardsize(source, &stmp);
+ (void) pthread_attr_setguardsize(pa_ptr, stmp);
+ (void) pthread_attr_getstackaddr(source, &vtmp);
+ (void) pthread_attr_setstackaddr(pa_ptr, vtmp);
+ (void) pthread_attr_getscope(source, &tmp);
+ (void) pthread_attr_setscope(pa_ptr, tmp);
+ (void) pthread_attr_getschedparam(source, &sp_tmp);
+ (void) pthread_attr_setschedparam(pa_ptr, &sp_tmp);
+#ifndef GC_AIX_THREADS
+ (void) pthread_attr_getprocessor_np(source, &ps_tmp, &tmp);
+ (void) pthread_attr_setprocessor_np(pa_ptr, ps_tmp, tmp);
+#endif
+ }
+# else
+# define copy_attr(pa_ptr, source) *(pa_ptr) = *(source)
+# endif
+
+int
+GC_pthread_create(pthread_t *new_thread,
+ const pthread_attr_t *attr,
+ void *(*start_routine)(void *), void *arg)
+{
+ int result;
+ GC_thread t;
+ void * stack;
+ size_t stacksize;
+ pthread_attr_t new_attr;
+ int detachstate;
+ word my_flags = 0;
+ struct start_info * si = GC_malloc(sizeof(struct start_info));
+
+ /* This is otherwise saved only in an area mmapped by the thread */
+ /* library, which isn't visible to the collector. */
+
+ if (0 == si) return(ENOMEM);
+ pthread_mutex_init(&(si->registeredlock), NULL);
+ pthread_cond_init(&(si->registered),NULL);
+ si -> start_routine = start_routine;
+ si -> arg = arg;
+ LOCK();
+ if (!GC_thr_initialized) GC_thr_init();
+
+ if (NULL == attr) {
+ stack = 0;
+ (void) pthread_attr_init(&new_attr);
+ } else {
+ copy_attr(&new_attr, attr);
+ pthread_attr_getstackaddr(&new_attr, &stack);
+ }
+ pthread_attr_getstacksize(&new_attr, &stacksize);
+ pthread_attr_getdetachstate(&new_attr, &detachstate);
+#ifdef GC_AIX_THREADS
+ GC_min_stack_sz = 5*1048576;
+ if (stacksize < GC_min_stack_sz) {
+ stacksize = GC_min_stack_sz;
+ }
+ { int alignment = 16*1024; /* size must be multiple of 16KB greater than 56KB */
+ int minval = 56*1024;
+ if ((stacksize - minval) % alignment != 0) {
+ stacksize = minval + alignment * ((stacksize-minval)/alignment + 1);
+ }
+ }
+#endif
+ if (0 == stack) {
+ stack = (void *)GC_stack_alloc(&stacksize);
+ if (0 == stack) {
+ UNLOCK();
+ return(ENOMEM);
+ }
+ pthread_attr_setstacksize(&new_attr, stacksize);
+#ifdef GC_AIX_THREADS
+ pthread_attr_setstackaddr(&new_attr, ((char *)stack)+stacksize);
+#else
+ pthread_attr_setstackaddr(&new_attr, stack);
+#endif
+ } else {
+ my_flags |= CLIENT_OWNS_STACK;
+ }
+
+ if (PTHREAD_CREATE_DETACHED == detachstate) my_flags |= DETACHED;
+ si -> flags = my_flags;
+ si -> stack = stack;
+ si -> stack_size = stacksize;
+ result = pthread_create(new_thread, &new_attr, GC_start_routine, si);
+
+ if (0 == new_thread && !(my_flags & CLIENT_OWNS_STACK)) {
+ GC_stack_free(stack, stacksize);
+ }
+ UNLOCK();
+ /* Wait until child has been added to the thread table. */
+ /* This also ensures that we hold onto si until the child is done */
+ /* with it. Thus it doesn't matter whether it is otherwise */
+ /* visible to the collector. */
+
+ si->registereddone = 0;
+ pthread_mutex_lock(&(si->registeredlock));
+ while (!si->registereddone)
+ pthread_cond_wait(&(si->registered), &(si->registeredlock));
+ pthread_mutex_unlock(&(si->registeredlock));
+
+ pthread_cond_destroy(&(si->registered));
+ pthread_mutex_destroy(&(si->registeredlock));
+ pthread_attr_destroy(&new_attr);
+
+ return(result);
+}
+
+/* For now we use the pthreads locking primitives on HP/UX */
+
+VOLATILE GC_bool GC_collecting = 0; /* A hint that we're in the collector and */
+ /* holding the allocation lock for an */
+ /* extended period. */
+
+/* Reasonably fast spin locks. Basically the same implementation */
+/* as STL alloc.h. */
+
+#define SLEEP_THRESHOLD 3
+
+volatile unsigned int GC_allocate_lock = 0;
+#define GC_TRY_LOCK() !GC_test_and_set(&GC_allocate_lock)
+#define GC_LOCK_TAKEN GC_allocate_lock
+
+void GC_lock()
+{
+# define low_spin_max 30 /* spin cycles if we suspect uniprocessor */
+# define high_spin_max 1000 /* spin cycles for multiprocessor */
+ static unsigned spin_max = low_spin_max;
+ unsigned my_spin_max;
+ static unsigned last_spins = 0;
+ unsigned my_last_spins;
+ volatile unsigned junk;
+# define PAUSE junk *= junk; junk *= junk; junk *= junk; junk *= junk
+ int i;
+
+ if (GC_TRY_LOCK()) {
+ return;
+ }
+ junk = 0;
+ my_spin_max = spin_max;
+ my_last_spins = last_spins;
+ for (i = 0; i < my_spin_max; i++) {
+ if (GC_collecting) goto yield;
+ if (i < my_last_spins/2 || GC_LOCK_TAKEN) {
+ PAUSE;
+ continue;
+ }
+ if (GC_TRY_LOCK()) {
+ /*
+ * got it!
+ * Spinning worked. Thus we're probably not being scheduled
+ * against the other process with which we were contending.
+ * Thus it makes sense to spin longer the next time.
+ */
+ last_spins = i;
+ spin_max = high_spin_max;
+ return;
+ }
+ }
+ /* We are probably being scheduled against the other process. Sleep. */
+ spin_max = low_spin_max;
+yield:
+ for (i = 0;; ++i) {
+ if (GC_TRY_LOCK()) {
+ return;
+ }
+ if (i < SLEEP_THRESHOLD) {
+ sched_yield();
+ } else {
+ struct timespec ts;
+
+ if (i > 26) i = 26;
+ /* Don't wait for more than about 60msecs, even */
+ /* under extreme contention. */
+ ts.tv_sec = 0;
+ ts.tv_nsec = 1 << i;
+ nanosleep(&ts, 0);
+ }
+ }
+}
+
+# else /* !GC_IRIX_THREADS && !GC_AIX_THREADS */
+
+#ifndef LINT
+ int GC_no_Irix_threads;
+#endif
+
+# endif /* IRIX_THREADS */
+