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Finish user stack support. Change locking code to be safe in situations with different priorities.

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1998-06-25 19:27  Ulrich Drepper  <drepper@cygnus.com>

	* attr.c: Finish user stack support.  Change locking code to be safe
	in situations with different priorities.
	* cancel.c: Likewise.
	* condvar.c: Likewise.
	* internals.h: Likewise.
	* join.c: Likewise.
	* manager.c: Likewise.
	* mutex.c: Likewise.
	* pthread.c: Likewise.
	* ptlongjmp.c: Likewise.
	* queue.h: Likewise.
	* rwlock.c: Likewise.
	* semaphore.c: Likewise.
	* semaphore.h: Likewise.
	* signals.c: Likewise.
	* spinlock.c: Likewise.
	* spinlock.h: Likewise.
	Patches by Xavier leroy.

1998-06-25  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/pthread/pthread.h: Make [sg]et_stacksize and
	[sg]et_stackaddr prototypes always available.

	* sysdeps/unix/sysv/linux/bits/posix_opt.h: Define
	_POSIX_THREAD_ATTR_STACKSIZE and _POSIX_THREAD_ATTR_STACKADDR.
This commit is contained in:
Ulrich Drepper 1998-06-25 19:36:00 +00:00
parent d47aac3999
commit 3387a425e6
23 changed files with 633 additions and 512 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
Makeconfig
View File

@ -564,8 +564,9 @@ endif # $(+cflags) == ""
libio-include = -I$(..)libio
# These are the variables that the implicit compilation rules use.
CPPFLAGS = $(+includes) $(defines) -include $(..)include/libc-symbols.h \
$(sysdep-CPPFLAGS) $(CPPFLAGS-$(suffix $@)) $(CPPFLAGS-$(<F)) \
CPPFLAGS = $($(subdir)-CPPFLAGS) $(+includes) $(defines) \
-include $(..)include/libc-symbols.h $(sysdep-CPPFLAGS) \
$($(subdir)-CPPFLAGS) $(CPPFLAGS-$(suffix $@)) $(CPPFLAGS-$(<F)) \
$(CPPFLAGS-$(@F))
override CFLAGS = $(filter-out %frame-pointer,$(+cflags)) $(sysdep-CFLAGS) \
$(CFLAGS-$(suffix $@)) $(CFLAGS-$(<F)) $(CFLAGS-$(@F))

3
libc.map
View File

@ -87,7 +87,8 @@ GLIBC_2.0 {
__ffs;
__close; __connect; __fcntl; __lseek; __open; __read; __send; __wait;
__ieee_get_fp_control; __ieee_set_fp_control;
__dgettext;
__dgettext; __sigaction;
# libio
_IO_adjust_column; _IO_clearerr; _IO_default_doallocate;
_IO_default_finish; _IO_default_pbackfail; _IO_default_uflow;

29
linuxthreads/ChangeLog
View File

@ -1,3 +1,32 @@
1998-06-25 19:27 Ulrich Drepper <drepper@cygnus.com>
* attr.c: Finish user stack support. Change locking code to be safe
in situations with different priorities.
* cancel.c: Likewise.
* condvar.c: Likewise.
* internals.h: Likewise.
* join.c: Likewise.
* manager.c: Likewise.
* mutex.c: Likewise.
* pthread.c: Likewise.
* ptlongjmp.c: Likewise.
* queue.h: Likewise.
* rwlock.c: Likewise.
* semaphore.c: Likewise.
* semaphore.h: Likewise.
* signals.c: Likewise.
* spinlock.c: Likewise.
* spinlock.h: Likewise.
Patches by Xavier leroy.
1998-06-25 Ulrich Drepper <drepper@cygnus.com>
* sysdeps/pthread/pthread.h: Make [sg]et_stacksize and
[sg]et_stackaddr prototypes always available.
* sysdeps/unix/sysv/linux/bits/posix_opt.h: Define
_POSIX_THREAD_ATTR_STACKSIZE and _POSIX_THREAD_ATTR_STACKADDR.
1998-06-24 Ulrich Drepper <drepper@cygnus.com>
* manager.c (pthread_free): Undo patch from 980430.

8
linuxthreads/attr.c
View File

@ -19,7 +19,6 @@
#include "pthread.h"
#include "internals.h"
int __pthread_attr_init_2_1(pthread_attr_t *attr)
{
size_t ps = __getpagesize ();
@ -185,11 +184,8 @@ weak_alias (__pthread_attr_getstackaddr, pthread_attr_getstackaddr)
int __pthread_attr_setstacksize(pthread_attr_t *attr, size_t stacksize)
{
size_t ps = __getpagesize ();
/* We don't accept value smaller than PTHREAD_STACK_MIN or bigger than
2MB - pagesize. */
if (stacksize < PTHREAD_STACK_MIN || stacksize > STACK_SIZE - ps)
/* We don't accept value smaller than PTHREAD_STACK_MIN. */
if (stacksize < PTHREAD_STACK_MIN)
return EINVAL;
attr->stacksize = stacksize;

6
linuxthreads/cancel.c
View File

@ -53,14 +53,14 @@ int pthread_cancel(pthread_t thread)
pthread_handle handle = thread_handle(thread);
int pid;
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread)) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
handle->h_descr->p_canceled = 1;
pid = handle->h_descr->p_pid;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
kill(pid, PTHREAD_SIG_CANCEL);
return 0;
}

79
linuxthreads/condvar.c
View File

@ -25,42 +25,36 @@
#include "queue.h"
#include "restart.h"
static void remove_from_queue(pthread_queue * q, pthread_descr th);
int pthread_cond_init(pthread_cond_t *cond,
const pthread_condattr_t *cond_attr)
{
cond->c_spinlock = 0;
queue_init(&cond->c_waiting);
__pthread_init_lock(&cond->c_lock);
cond->c_waiting = NULL;
return 0;
}
int pthread_cond_destroy(pthread_cond_t *cond)
{
pthread_descr head;
acquire(&cond->c_spinlock);
head = cond->c_waiting.head;
release(&cond->c_spinlock);
if (head != NULL) return EBUSY;
if (cond->c_waiting != NULL) return EBUSY;
return 0;
}
int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
{
volatile pthread_descr self = thread_self();
acquire(&cond->c_spinlock);
__pthread_lock(&cond->c_lock);
enqueue(&cond->c_waiting, self);
release(&cond->c_spinlock);
__pthread_unlock(&cond->c_lock);
pthread_mutex_unlock(mutex);
suspend_with_cancellation(self);
pthread_mutex_lock(mutex);
/* This is a cancellation point */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
/* Remove ourselves from the waiting queue if we're still on it */
acquire(&cond->c_spinlock);
__pthread_lock(&cond->c_lock);
remove_from_queue(&cond->c_waiting, self);
release(&cond->c_spinlock);
__pthread_unlock(&cond->c_lock);
pthread_exit(PTHREAD_CANCELED);
}
return 0;
@ -77,15 +71,14 @@ pthread_cond_timedwait_relative(pthread_cond_t *cond,
sigjmp_buf jmpbuf;
/* Wait on the condition */
acquire(&cond->c_spinlock);
__pthread_lock(&cond->c_lock);
enqueue(&cond->c_waiting, self);
release(&cond->c_spinlock);
__pthread_unlock(&cond->c_lock);
pthread_mutex_unlock(mutex);
/* Set up a longjmp handler for the restart signal */
/* No need to save the signal mask, since PTHREAD_SIG_RESTART will be
blocked when doing the siglongjmp, and we'll just leave it blocked. */
if (sigsetjmp(jmpbuf, 0) == 0) {
/* Set up a longjmp handler for the restart and cancel signals */
if (sigsetjmp(jmpbuf, 1) == 0) {
self->p_signal_jmp = &jmpbuf;
self->p_cancel_jmp = &jmpbuf;
self->p_signal = 0;
/* Check for cancellation */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
@ -104,28 +97,28 @@ pthread_cond_timedwait_relative(pthread_cond_t *cond,
retsleep = -1;
}
self->p_signal_jmp = NULL;
self->p_cancel_jmp = NULL;
/* Here, either the condition was signaled (self->p_signal != 0)
or we got canceled (self->p_canceled != 0)
or the timeout occurred (retsleep == 0)
or another interrupt occurred (retsleep == -1) */
/* Re-acquire the spinlock */
acquire(&cond->c_spinlock);
/* This is a cancellation point */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
__pthread_lock(&cond->c_lock);
remove_from_queue(&cond->c_waiting, self);
release(&cond->c_spinlock);
__pthread_unlock(&cond->c_lock);
pthread_mutex_lock(mutex);
pthread_exit(PTHREAD_CANCELED);
}
/* If not signaled: also remove ourselves and return an error code */
if (self->p_signal == 0) {
__pthread_lock(&cond->c_lock);
remove_from_queue(&cond->c_waiting, self);
release(&cond->c_spinlock);
__pthread_unlock(&cond->c_lock);
pthread_mutex_lock(mutex);
return retsleep == 0 ? ETIMEDOUT : EINTR;
}
/* Otherwise, return normally */
release(&cond->c_spinlock);
pthread_mutex_lock(mutex);
return 0;
}
@ -151,23 +144,22 @@ int pthread_cond_signal(pthread_cond_t *cond)
{
pthread_descr th;
acquire(&cond->c_spinlock);
__pthread_lock(&cond->c_lock);
th = dequeue(&cond->c_waiting);
release(&cond->c_spinlock);
__pthread_unlock(&cond->c_lock);
if (th != NULL) restart(th);
return 0;
}
int pthread_cond_broadcast(pthread_cond_t *cond)
{
pthread_queue tosignal;
pthread_descr th;
pthread_descr tosignal, th;
acquire(&cond->c_spinlock);
__pthread_lock(&cond->c_lock);
/* Copy the current state of the waiting queue and empty it */
tosignal = cond->c_waiting;
queue_init(&cond->c_waiting);
release(&cond->c_spinlock);
cond->c_waiting = NULL;
__pthread_unlock(&cond->c_lock);
/* Now signal each process in the queue */
while ((th = dequeue(&tosignal)) != NULL) restart(th);
return 0;
@ -182,26 +174,3 @@ int pthread_condattr_destroy(pthread_condattr_t *attr)
{
return 0;
}
/* Auxiliary function on queues */
static void remove_from_queue(pthread_queue * q, pthread_descr th)
{
pthread_descr t;
if (q->head == NULL) return;
if (q->head == th) {
q->head = th->p_nextwaiting;
if (q->head == NULL) q->tail = NULL;
th->p_nextwaiting = NULL;
return;
}
for (t = q->head; t->p_nextwaiting != NULL; t = t->p_nextwaiting) {
if (t->p_nextwaiting == th) {
t->p_nextwaiting = th->p_nextwaiting;
if (th->p_nextwaiting == NULL) q->tail = t;
th->p_nextwaiting = NULL;
return;
}
}
}

28
linuxthreads/internals.h
View File

@ -63,7 +63,7 @@ struct _pthread_descr_struct {
pthread_t p_tid; /* Thread identifier */
int p_pid; /* PID of Unix process */
int p_priority; /* Thread priority (== 0 if not realtime) */
int * p_spinlock; /* Spinlock for synchronized accesses */
struct _pthread_fastlock * p_lock; /* Spinlock for synchronized accesses */
int p_signal; /* last signal received */
sigjmp_buf * p_signal_jmp; /* where to siglongjmp on a signal or NULL */
sigjmp_buf * p_cancel_jmp; /* where to siglongjmp on a cancel or NULL */
@ -81,6 +81,8 @@ struct _pthread_descr_struct {
int p_errno; /* error returned by last system call */
int * p_h_errnop; /* pointer to used h_errno variable */
int p_h_errno; /* error returned by last netdb function */
char * p_in_sighandler; /* stack address of sighandler, or NULL */
char p_sigwaiting; /* true if a sigwait() is in progress */
struct pthread_start_args p_start_args; /* arguments for thread creation */
void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE]; /* thread-specific data */
void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */
@ -94,8 +96,9 @@ struct _pthread_descr_struct {
typedef struct pthread_handle_struct * pthread_handle;
struct pthread_handle_struct {
int h_spinlock; /* Spinlock for sychronized access */
struct _pthread_fastlock h_lock; /* Fast lock for sychronized access */
pthread_descr h_descr; /* Thread descriptor or NULL if invalid */
char * h_bottom; /* Lowest address in the stack thread */
};
/* The type of messages sent to the thread manager thread */
@ -103,7 +106,8 @@ struct pthread_handle_struct {
struct pthread_request {
pthread_descr req_thread; /* Thread doing the request */
enum { /* Request kind */
REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT
REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT,
REQ_POST, REQ_DEBUG
} req_kind;
union { /* Arguments for request */
struct { /* For REQ_CREATE: */
@ -118,6 +122,7 @@ struct pthread_request {
struct { /* For REQ_PROCESS_EXIT: */
int code; /* exit status */
} exit;
void * post; /* For REQ_POST: the semaphore */
} req_args;
};
@ -160,6 +165,11 @@ extern pthread_descr __pthread_main_thread;
extern char *__pthread_initial_thread_bos;
/* Indicate whether at least one thread has a user-defined stack (if 1),
or all threads have stacks supplied by LinuxThreads (if 0). */
extern int __pthread_nonstandard_stacks;
/* File descriptor for sending requests to the thread manager.
Initially -1, meaning that pthread_initialize must be called. */
@ -178,6 +188,10 @@ extern char *__pthread_manager_thread_tos;
extern int __pthread_exit_requested, __pthread_exit_code;
/* Set to 1 by gdb if we're debugging */
extern volatile int __pthread_threads_debug;
/* Return the handle corresponding to a thread id */
static inline pthread_handle thread_handle(pthread_t id)
@ -233,6 +247,8 @@ static inline int invalid_handle(pthread_handle h, pthread_t id)
/* Recover thread descriptor for the current thread */
extern pthread_descr __pthread_find_self (void) __attribute__ ((const));
static inline pthread_descr thread_self (void) __attribute__ ((const));
static inline pthread_descr thread_self (void)
{
@ -245,6 +261,8 @@ static inline pthread_descr thread_self (void)
else if (sp >= __pthread_manager_thread_bos
&& sp < __pthread_manager_thread_tos)
return &__pthread_manager_thread;
else if (__pthread_nonstandard_stacks)
return __pthread_find_self();
else
return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1;
#endif
@ -282,8 +300,8 @@ static inline pthread_descr thread_self (void)
void __pthread_destroy_specifics(void);
void __pthread_perform_cleanup(void);
void __pthread_sighandler(int sig);
void __pthread_message(char * fmt, long arg, ...);
int __pthread_initialize_manager(void);
void __pthread_message(char * fmt, ...);
int __pthread_manager(void *reqfd);
void __pthread_manager_sighandler(int sig);
void __pthread_reset_main_thread(void);

28
linuxthreads/join.c
View File

@ -35,13 +35,13 @@ void pthread_exit(void * retval)
__pthread_perform_cleanup();
__pthread_destroy_specifics();
/* Store return value */
acquire(self->p_spinlock);
__pthread_lock(self->p_lock);
self->p_retval = retval;
/* Say that we've terminated */
self->p_terminated = 1;
/* See if someone is joining on us */
joining = self->p_joining;
release(self->p_spinlock);
__pthread_unlock(self->p_lock);
/* Restart joining thread if any */
if (joining != NULL) restart(joining);
/* If this is the initial thread, block until all threads have terminated.
@ -65,36 +65,36 @@ int pthread_join(pthread_t thread_id, void ** thread_return)
pthread_handle handle = thread_handle(thread_id);
pthread_descr th;
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread_id)) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
th = handle->h_descr;
if (th == self) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return EDEADLK;
}
/* If detached or already joined, error */
if (th->p_detached || th->p_joining != NULL) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return EINVAL;
}
/* If not terminated yet, suspend ourselves. */
if (! th->p_terminated) {
th->p_joining = self;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
suspend_with_cancellation(self);
/* This is a cancellation point */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
th->p_joining = NULL;
pthread_exit(PTHREAD_CANCELED);
}
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
}
/* Get return value */
if (thread_return != NULL) *thread_return = th->p_retval;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
/* Send notification to thread manager */
if (__pthread_manager_request >= 0) {
request.req_thread = self;
@ -113,26 +113,26 @@ int pthread_detach(pthread_t thread_id)
pthread_handle handle = thread_handle(thread_id);
pthread_descr th;
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread_id)) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
th = handle->h_descr;
/* If already detached, error */
if (th->p_detached) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return EINVAL;
}
/* If already joining, don't do anything. */
if (th->p_joining != NULL) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return 0;
}
/* Mark as detached */
th->p_detached = 1;
terminated = th->p_terminated;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
/* If already terminated, notify thread manager to reclaim resources */
if (terminated && __pthread_manager_request >= 0) {
request.req_thread = thread_self();

79
linuxthreads/manager.c
View File

@ -31,15 +31,22 @@
#include "internals.h"
#include "spinlock.h"
#include "restart.h"
#include "semaphore.h"
/* Array of active threads. Entry 0 is reserved for the initial thread. */
struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX] =
{ { 0, &__pthread_initial_thread, 0}, /* All NULLs */ };
{ { LOCK_INITIALIZER, &__pthread_initial_thread, 0}, /* All NULLs */ };
/* Indicate whether at least one thread has a user-defined stack (if 1),
or if all threads have stacks supplied by LinuxThreads (if 0). */
int __pthread_nonstandard_stacks;
int __pthread_nonstandard_stacks = 0;
/* Number of active entries in __pthread_handles (used by gdb) */
volatile int __pthread_handles_num = 1;
/* Whether to use debugger additional actions for thread creation
(set to 1 by gdb) */
volatile int __pthread_threads_debug = 0;
/* Mapping from stack segment to thread descriptor. */
/* Stack segment numbers are also indices into the __pthread_handles array. */
@ -93,12 +100,18 @@ int __pthread_manager(void *arg)
/* Set the error variable. */
__pthread_manager_thread.p_errnop = &__pthread_manager_thread.p_errno;
__pthread_manager_thread.p_h_errnop = &__pthread_manager_thread.p_h_errno;
/* Block all signals except PTHREAD_SIG_RESTART */
/* Block all signals except PTHREAD_SIG_RESTART, PTHREAD_SIG_CANCEL
and SIGTRAP */
sigfillset(&mask);
sigdelset(&mask, PTHREAD_SIG_RESTART);
sigdelset(&mask, PTHREAD_SIG_CANCEL); /* for debugging new threads */
sigdelset(&mask, SIGTRAP); /* for debugging purposes */
sigprocmask(SIG_SETMASK, &mask, NULL);
/* Raise our priority to match that of main thread */
__pthread_manager_adjust_prio(__pthread_main_thread->p_priority);
/* Synchronize debugging of the thread manager */
n = __libc_read(reqfd, (char *)&request, sizeof(request));
ASSERT(n == sizeof(request) && request.req_kind == REQ_DEBUG);
/* Enter server loop */
while(1) {
FD_ZERO(&readfds);
@ -146,6 +159,14 @@ int __pthread_manager(void *arg)
return 0;
}
break;
case REQ_POST:
sem_post(request.req_args.post);
break;
case REQ_DEBUG:
/* Make gdb aware of new thread */
if (__pthread_threads_debug) raise(PTHREAD_SIG_CANCEL);
restart(request.req_thread);
break;
}
}
}
@ -156,6 +177,7 @@ int __pthread_manager(void *arg)
static int pthread_start_thread(void *arg)
{
pthread_descr self = (pthread_descr) arg;
struct pthread_request request;
void * outcome;
/* Initialize special thread_self processing, if any. */
#ifdef INIT_THREAD_SELF
@ -171,6 +193,14 @@ static int pthread_start_thread(void *arg)
if (self->p_start_args.schedpolicy >= 0)
__sched_setscheduler(self->p_pid, self->p_start_args.schedpolicy,
&self->p_start_args.schedparam);
/* Make gdb aware of new thread */
if (__pthread_threads_debug) {
request.req_thread = self;
request.req_kind = REQ_DEBUG;
__libc_write(__pthread_manager_request,
(char *) &request, sizeof(request));
suspend(self);
}
/* Run the thread code */
outcome = self->p_start_args.start_routine(self->p_start_args.arg);
/* Exit with the given return value */
@ -188,6 +218,7 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
char * new_thread_bottom;
pthread_t new_thread_id;
void *guardaddr = NULL;
size_t guardsize = 0;
/* Find a free stack segment for the current stack */
for (sseg = 1; ; sseg++)
@ -211,13 +242,16 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
and allocate it if necessary. */
if (attr == NULL || attr->guardsize != 0)
{
guardsize = attr ? attr->guardsize : __getpagesize ();
guardaddr = mmap ((caddr_t)((char *)(new_thread+1)
- STACK_SIZE),
attr ? attr->guardsize : __getpagesize (),
0, MAP_FIXED, -1, 0);
guardsize, 0, MAP_FIXED, -1, 0);
if (guardaddr == MAP_FAILED)
/* We don't make this an error. */
guardaddr = NULL;
{
/* We don't make this an error. */
guardaddr = NULL;
guardsize = 0;
}
}
break;
}
@ -238,7 +272,7 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
new_thread->p_nextwaiting = NULL;
new_thread->p_tid = new_thread_id;
new_thread->p_priority = 0;
new_thread->p_spinlock = &(__pthread_handles[sseg].h_spinlock);
new_thread->p_lock = &(__pthread_handles[sseg].h_lock);
new_thread->p_signal = 0;
new_thread->p_signal_jmp = NULL;
new_thread->p_cancel_jmp = NULL;
@ -255,16 +289,15 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
new_thread->p_errno = 0;
new_thread->p_h_errnop = &new_thread->p_h_errno;
new_thread->p_h_errno = 0;
new_thread->p_in_sighandler = NULL;
new_thread->p_sigwaiting = 0;
new_thread->p_guardaddr = guardaddr;
new_thread->p_guardsize = (guardaddr == NULL
? 0
: (attr == NULL
? __getpagesize () : attr->guardsize));
new_thread->p_guardsize = guardsize;
new_thread->p_userstack = attr != NULL && attr->stackaddr_set;
memset (new_thread->p_specific, '\0',
PTHREAD_KEY_1STLEVEL_SIZE * sizeof (new_thread->p_specific[0]));
/* Initialize the thread handle */
__pthread_handles[sseg].h_spinlock = 0; /* should already be 0 */
__pthread_init_lock(&__pthread_handles[sseg].h_lock);
__pthread_handles[sseg].h_descr = new_thread;
__pthread_handles[sseg].h_bottom = new_thread_bottom;
/* Determine scheduling parameters for the thread */
@ -305,6 +338,8 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
munmap(new_thread->p_guardaddr, new_thread->p_guardsize);
}
__pthread_handles[sseg].h_descr = NULL;
__pthread_handles[sseg].h_bottom = NULL;
__pthread_handles_num--;
return errno;
}
/* Insert new thread in doubly linked list of active threads */
@ -330,10 +365,12 @@ static void pthread_free(pthread_descr th)
ASSERT(th->p_exited);
/* Make the handle invalid */
handle = thread_handle(th->p_tid);
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
handle->h_descr = NULL;
handle->h_bottom = (char *)(-1L);
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
/* One fewer threads in __pthread_handles */
__pthread_handles_num--;
/* If initial thread, nothing to free */
if (th == &__pthread_initial_thread) return;
if (!th->p_userstack)
@ -360,10 +397,10 @@ static void pthread_exited(pid_t pid)
th->p_nextlive->p_prevlive = th->p_prevlive;
th->p_prevlive->p_nextlive = th->p_nextlive;
/* Mark thread as exited, and if detached, free its resources */
acquire(th->p_spinlock);
__pthread_lock(th->p_lock);
th->p_exited = 1;
detached = th->p_detached;
release(th->p_spinlock);
__pthread_unlock(th->p_lock);
if (detached) pthread_free(th);
break;
}
@ -409,16 +446,16 @@ static void pthread_handle_free(pthread_descr th)
} while (t != __pthread_main_thread);
if (t != th) return;
acquire(th->p_spinlock);
__pthread_lock(th->p_lock);
if (th->p_exited) {
release(th->p_spinlock);
__pthread_unlock(th->p_lock);
pthread_free(th);
} else {
/* The Unix process of the thread is still running.
Mark the thread as detached so that the thread manager will
deallocate its resources when the Unix process exits. */
th->p_detached = 1;
release(th->p_spinlock);
__pthread_unlock(th->p_lock);
}
}

122
linuxthreads/mutex.c
View File

@ -26,23 +26,18 @@
int __pthread_mutex_init(pthread_mutex_t * mutex,
const pthread_mutexattr_t * mutex_attr)
{
mutex->m_spinlock = 0;
mutex->m_count = 0;
mutex->m_owner = NULL;
__pthread_init_lock(&mutex->m_lock);
mutex->m_kind =
mutex_attr == NULL ? PTHREAD_MUTEX_FAST_NP : mutex_attr->mutexkind;
queue_init(&mutex->m_waiting);
mutex->m_count = 0;
mutex->m_owner = NULL;
return 0;
}
weak_alias (__pthread_mutex_init, pthread_mutex_init)
int __pthread_mutex_destroy(pthread_mutex_t * mutex)
{
int count;
acquire(&mutex->m_spinlock);
count = mutex->m_count;
release(&mutex->m_spinlock);
if (count > 0) return EBUSY;
if (mutex->m_lock.status != 0) return EBUSY;
return 0;
}
weak_alias (__pthread_mutex_destroy, pthread_mutex_destroy)
@ -50,40 +45,33 @@ weak_alias (__pthread_mutex_destroy, pthread_mutex_destroy)
int __pthread_mutex_trylock(pthread_mutex_t * mutex)
{
pthread_descr self;
int retcode;
acquire(&mutex->m_spinlock);
switch(mutex->m_kind) {
case PTHREAD_MUTEX_FAST_NP:
if (mutex->m_count == 0) {
mutex->m_count = 1;
release(&mutex->m_spinlock);
return 0;
}
break;
retcode = __pthread_trylock(&mutex->m_lock);
return retcode;
case PTHREAD_MUTEX_RECURSIVE_NP:
self = thread_self();
if (mutex->m_count == 0 || mutex->m_owner == self) {
if (mutex->m_owner == self) {
mutex->m_count++;
mutex->m_owner = self;
release(&mutex->m_spinlock);
return 0;
}
break;
retcode = __pthread_trylock(&mutex->m_lock);
if (retcode == 0) {
mutex->m_owner = self;
mutex->m_count = 0;
}
return retcode;
case PTHREAD_MUTEX_ERRORCHECK_NP:
self = thread_self();
if (mutex->m_count == 0) {
mutex->m_count = 1;
mutex->m_owner = self;
release(&mutex->m_spinlock);
return 0;
retcode = __pthread_trylock(&mutex->m_lock);
if (retcode == 0) {
mutex->m_owner = thread_self();
}
break;
return retcode;
default:
release(&mutex->m_spinlock);
return EINVAL;
}
release(&mutex->m_spinlock);
return EBUSY;
}
weak_alias (__pthread_mutex_trylock, pthread_mutex_trylock)
@ -91,87 +79,55 @@ int __pthread_mutex_lock(pthread_mutex_t * mutex)
{
pthread_descr self;
acquire(&mutex->m_spinlock);
switch(mutex->m_kind) {
case PTHREAD_MUTEX_FAST_NP:
if (mutex->m_count == 0) {
mutex->m_count = 1;
release(&mutex->m_spinlock);
return 0;
}
self = thread_self();
break;
__pthread_lock(&mutex->m_lock);
return 0;
case PTHREAD_MUTEX_RECURSIVE_NP:
self = thread_self();
if (mutex->m_count == 0 || mutex->m_owner == self) {
if (mutex->m_owner == self) {
mutex->m_count++;
mutex->m_owner = self;
release(&mutex->m_spinlock);
return 0;
}
break;
__pthread_lock(&mutex->m_lock);
mutex->m_owner = self;
mutex->m_count = 0;
return 0;
case PTHREAD_MUTEX_ERRORCHECK_NP:
self = thread_self();
if (mutex->m_count == 0) {
mutex->m_count = 1;
mutex->m_owner = self;
release(&mutex->m_spinlock);
return 0;
} else if (mutex->m_owner == self) {
release(&mutex->m_spinlock);
return EDEADLK;
}
break;
if (mutex->m_owner == self) return EDEADLK;
__pthread_lock(&mutex->m_lock);
mutex->m_owner = self;
return 0;
default:
release(&mutex->m_spinlock);
return EINVAL;
}
/* Suspend ourselves */
enqueue(&mutex->m_waiting, self);
release(&mutex->m_spinlock);
suspend(self); /* This is not a cancellation point */
/* Now we own the mutex */
ASSERT(mutex->m_count == 1);
mutex->m_owner = self; /* for recursive and errorcheck mutexes */
return 0;
}
weak_alias (__pthread_mutex_lock, pthread_mutex_lock)
int __pthread_mutex_unlock(pthread_mutex_t * mutex)
{
pthread_descr th;
acquire(&mutex->m_spinlock);
switch (mutex->m_kind) {
case PTHREAD_MUTEX_FAST_NP:
break;
__pthread_unlock(&mutex->m_lock);
return 0;
case PTHREAD_MUTEX_RECURSIVE_NP:
if (mutex->m_count >= 2) {
if (mutex->m_count > 0) {
mutex->m_count--;
release(&mutex->m_spinlock);
return 0;
}
break;
mutex->m_owner = NULL;
__pthread_unlock(&mutex->m_lock);
return 0;
case PTHREAD_MUTEX_ERRORCHECK_NP:
if (mutex->m_count == 0 || mutex->m_owner != thread_self()) {
release(&mutex->m_spinlock);
if (mutex->m_owner != thread_self() || mutex->m_lock.status == 0)
return EPERM;
}
break;
mutex->m_owner = NULL;
__pthread_unlock(&mutex->m_lock);
return 0;
default:
release(&mutex->m_spinlock);
return EINVAL;
}
th = dequeue(&mutex->m_waiting);
/* If no waiters, unlock the mutex */
if (th == NULL) mutex->m_count = 0;
release(&mutex->m_spinlock);
/* If there is a waiter, restart it with the mutex still locked */
if (th != NULL) {
mutex->m_owner = NULL; /* we no longer own the mutex */
restart(th);
}
return 0;
}
weak_alias (__pthread_mutex_unlock, pthread_mutex_unlock)

89
linuxthreads/pthread.c
View File

@ -35,7 +35,7 @@ struct _pthread_descr_struct __pthread_initial_thread = {
PTHREAD_THREADS_MAX, /* pthread_t p_tid */
0, /* int p_pid */
0, /* int p_priority */
&__pthread_handles[0].h_spinlock, /* int * p_spinlock */
&__pthread_handles[0].h_lock, /* struct _pthread_fastlock * p_lock */
0, /* int p_signal */
NULL, /* sigjmp_buf * p_signal_buf */
NULL, /* sigjmp_buf * p_cancel_buf */
@ -53,6 +53,8 @@ struct _pthread_descr_struct __pthread_initial_thread = {
0, /* int p_errno */
NULL, /* int *p_h_errnop */
0, /* int p_h_errno */
NULL, /* char * p_in_sighandler */
0, /* char p_sigwaiting */
PTHREAD_START_ARGS_INITIALIZER, /* struct pthread_start_args p_start_args */
{NULL} /* void * p_specific[PTHREAD_KEYS_MAX] */
};
@ -68,7 +70,7 @@ struct _pthread_descr_struct __pthread_manager_thread = {
0, /* int p_tid */
0, /* int p_pid */
0, /* int p_priority */
NULL, /* int * p_spinlock */
NULL, /* struct _pthread_fastlock * p_lock */
0, /* int p_signal */
NULL, /* sigjmp_buf * p_signal_buf */
NULL, /* sigjmp_buf * p_cancel_buf */
@ -86,6 +88,8 @@ struct _pthread_descr_struct __pthread_manager_thread = {
0, /* int p_errno */
NULL, /* int *p_h_errnop */
0, /* int p_h_errno */
NULL, /* char * p_in_sighandler */
0, /* char p_sigwaiting */
PTHREAD_START_ARGS_INITIALIZER, /* struct pthread_start_args p_start_args */
{NULL} /* void * p_specific[PTHREAD_KEYS_MAX] */
};
@ -119,6 +123,15 @@ char *__pthread_manager_thread_tos = NULL;
int __pthread_exit_requested = 0;
int __pthread_exit_code = 0;
/* Communicate relevant LinuxThreads constants to gdb */
const int __pthread_threads_max = PTHREAD_THREADS_MAX;
const int __pthread_sizeof_handle = sizeof(struct pthread_handle_struct);
const int __pthread_offsetof_descr = offsetof(struct pthread_handle_struct,
h_descr);
const int __pthread_offsetof_pid = offsetof(struct _pthread_descr_struct,
p_pid);
/* Signal numbers used for the communication. */
int __pthread_sig_restart;
int __pthread_sig_cancel;
@ -131,6 +144,7 @@ extern int _h_errno;
static void pthread_exit_process(int retcode, void *arg);
static void pthread_handle_sigcancel(int sig);
static void pthread_handle_sigrestart(int sig);
/* Initialize the pthread library.
Initialization is split in two functions:
@ -148,6 +162,10 @@ static void pthread_initialize(void)
/* If already done (e.g. by a constructor called earlier!), bail out */
if (__pthread_initial_thread_bos != NULL) return;
#ifdef TEST_FOR_COMPARE_AND_SWAP
/* Test if compare-and-swap is available */
__pthread_has_cas = compare_and_swap_is_available();
#endif
/* For the initial stack, reserve at least STACK_SIZE bytes of stack
below the current stack address, and align that on a
STACK_SIZE boundary. */
@ -178,14 +196,14 @@ static void pthread_initialize(void)
/* Setup signal handlers for the initial thread.
Since signal handlers are shared between threads, these settings
will be inherited by all other threads. */
sa.sa_handler = __pthread_sighandler;
sa.sa_handler = pthread_handle_sigrestart;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART; /* does not matter for regular threads, but
better for the thread manager */
sigaction(PTHREAD_SIG_RESTART, &sa, NULL);
__sigaction(PTHREAD_SIG_RESTART, &sa, NULL);
sa.sa_handler = pthread_handle_sigcancel;
sa.sa_flags = 0;
sigaction(PTHREAD_SIG_CANCEL, &sa, NULL);
__sigaction(PTHREAD_SIG_CANCEL, &sa, NULL);
/* Initially, block PTHREAD_SIG_RESTART. Will be unblocked on demand. */
sigemptyset(&mask);
@ -197,10 +215,11 @@ static void pthread_initialize(void)
__on_exit(pthread_exit_process, NULL);
}
static int pthread_initialize_manager(void)
int __pthread_initialize_manager(void)
{
int manager_pipe[2];
int pid;
struct pthread_request request;
/* If basic initialization not done yet (e.g. we're called from a
constructor run before our constructor), do it now */
@ -228,6 +247,11 @@ static int pthread_initialize_manager(void)
__pthread_manager_request = manager_pipe[1]; /* writing end */
__pthread_manager_reader = manager_pipe[0]; /* reading end */
__pthread_manager_thread.p_pid = pid;
/* Make gdb aware of new thread manager */
if (__pthread_threads_debug) raise(PTHREAD_SIG_CANCEL);
/* Synchronize debugging of the thread manager */
request.req_kind = REQ_DEBUG;
__libc_write(__pthread_manager_request, (char *) &request, sizeof(request));
return 0;
}
@ -239,7 +263,7 @@ int __pthread_create_2_1(pthread_t *thread, const pthread_attr_t *attr,
pthread_descr self = thread_self();
struct pthread_request request;
if (__pthread_manager_request < 0) {
if (pthread_initialize_manager() < 0) return EAGAIN;
if (__pthread_initialize_manager() < 0) return EAGAIN;
}
request.req_thread = self;
request.req_kind = REQ_CREATE;
@ -296,6 +320,24 @@ int pthread_equal(pthread_t thread1, pthread_t thread2)
return thread1 == thread2;
}
/* Helper function for thread_self in the case of user-provided stacks */
#ifndef THREAD_SELF
pthread_descr __pthread_find_self()
{
char * sp = CURRENT_STACK_FRAME;
pthread_handle h;
/* __pthread_handles[0] is the initial thread, handled specially in
thread_self(), so start at 1 */
h = __pthread_handles + 1;
while (! (sp <= (char *) h->h_descr && sp >= h->h_bottom)) h++;
return h->h_descr;
}
#endif
/* Thread scheduling */
int pthread_setschedparam(pthread_t thread, int policy,
@ -304,18 +346,18 @@ int pthread_setschedparam(pthread_t thread, int policy,
pthread_handle handle = thread_handle(thread);
pthread_descr th;
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread)) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
th = handle->h_descr;
if (__sched_setscheduler(th->p_pid, policy, param) == -1) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return errno;
}
th->p_priority = policy == SCHED_OTHER ? 0 : param->sched_priority;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
if (__pthread_manager_request >= 0)
__pthread_manager_adjust_prio(th->p_priority);
return 0;
@ -327,13 +369,13 @@ int pthread_getschedparam(pthread_t thread, int *policy,
pthread_handle handle = thread_handle(thread);
int pid, pol;
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread)) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
pid = handle->h_descr->p_pid;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
pol = __sched_getscheduler(pid);
if (pol == -1) return errno;
if (__sched_getparam(pid, param) == -1) return errno;
@ -364,11 +406,11 @@ static void pthread_exit_process(int retcode, void *arg)
/* The handler for the RESTART signal just records the signal received
in the thread descriptor, and optionally performs a siglongjmp
(for pthread_cond_timedwait). Also used in sigwait.
(for pthread_cond_timedwait).
For the thread manager thread, redirect the signal to
__pthread_manager_sighandler. */
void __pthread_sighandler(int sig)
static void pthread_handle_sigrestart(int sig)
{
pthread_descr self = thread_self();
if (self == &__pthread_manager_thread) {
@ -380,13 +422,24 @@ void __pthread_sighandler(int sig)
}
/* The handler for the CANCEL signal checks for cancellation
(in asynchronous mode) and for process-wide exit and exec requests. */
(in asynchronous mode), for process-wide exit and exec requests.
For the thread manager thread, we ignore the signal.
The debugging strategy is as follows:
On reception of a REQ_DEBUG request (sent by new threads created to
the thread manager under debugging mode), the thread manager throws
PTHREAD_SIG_CANCEL to itself. The debugger (if active) intercepts
this signal, takes into account new threads and continue execution
of the thread manager by propagating the signal because it doesn't
know what it is specifically done for. In the current implementation,
the thread manager simply discards it. */
static void pthread_handle_sigcancel(int sig)
{
pthread_descr self = thread_self();
sigjmp_buf * jmpbuf;
if (self == &__pthread_manager_thread)
return;
if (__pthread_exit_requested) {
/* Main thread should accumulate times for thread manager and its
children, so that timings for main thread account for all threads. */
@ -469,7 +522,7 @@ weak_alias (__pthread_getconcurrency, pthread_getconcurrency)
#ifdef DEBUG
#include <stdarg.h>
void __pthread_message(char * fmt, long arg)
void __pthread_message(char * fmt, ...)
{
char buffer[1024];
va_list args;

2
linuxthreads/ptlongjmp.c
View File

@ -37,6 +37,8 @@ static void pthread_cleanup_upto(__jmp_buf target)
c = c->prev)
c->routine(c->arg);
self->p_cleanup = c;
if (self->p_in_sighandler && _JMPBUF_UNWINDS(target, self->p_in_sighandler))
self->p_in_sighandler = NULL;
}
void siglongjmp(sigjmp_buf env, int val)

57
linuxthreads/queue.h
View File

@ -14,49 +14,42 @@
/* Waiting queues */
typedef struct _pthread_queue pthread_queue;
/* Waiting queues are represented by lists of thread descriptors
linked through their p_nextwaiting field. The lists are kept
sorted by decreasing priority, and then decreasing waiting time. */
static inline void queue_init(pthread_queue * q)
static inline void enqueue(pthread_descr * q, pthread_descr th)
{
q->head = q->tail = NULL;
}
static inline void enqueue(pthread_queue * q, pthread_descr th)
{
int prio;
pthread_descr * elt;
int prio = th->p_priority;
ASSERT(th->p_nextwaiting == NULL);
if (q->tail == NULL) {
q->head = th;
q->tail = th;
return;
}
prio = th->p_priority;
if (prio > 0) {
/* Insert in queue according to priority order */
for (elt = &(q->head); *elt != NULL; elt = &((*elt)->p_nextwaiting)) {
if (prio > (*elt)->p_priority) {
th->p_nextwaiting = *elt;
*elt = th;
return;
}
for (; *q != NULL; q = &((*q)->p_nextwaiting)) {
if (prio > (*q)->p_priority) {
th->p_nextwaiting = *q;
*q = th;
return;
}
}
/* Priority is no greater than any thread in the queue.
Insert at end of queue */
q->tail->p_nextwaiting = th;
q->tail = th;
*q = th;
}
static inline pthread_descr dequeue(pthread_queue * q)
static inline pthread_descr dequeue(pthread_descr * q)
{
pthread_descr th;
th = q->head;
th = *q;
if (th != NULL) {
q->head = th->p_nextwaiting;
if (q->head == NULL) q->tail = NULL;
*q = th->p_nextwaiting;
th->p_nextwaiting = NULL;
}
return th;
}
static inline void remove_from_queue(pthread_descr * q, pthread_descr th)
{
for (; *q != NULL; q = &((*q)->p_nextwaiting)) {
if (*q == th) {
*q = th->p_nextwaiting;
th->p_nextwaiting = NULL;
return;
}
}
}

47
linuxthreads/rwlock.c
View File

@ -30,12 +30,11 @@ int
pthread_rwlock_init (pthread_rwlock_t *rwlock,
const pthread_rwlockattr_t *attr)
{
rwlock->rw_spinlock = 0;
__pthread_init_lock(&rwlock->rw_lock);
rwlock->rw_readers = 0;
rwlock->rw_writer = NULL;
queue_init(&rwlock->rw_read_waiting);
queue_init(&rwlock->rw_write_waiting);
rwlock->rw_read_waiting = NULL;
rwlock->rw_write_waiting = NULL;
if (attr == NULL)
{
@ -58,10 +57,10 @@ pthread_rwlock_destroy (pthread_rwlock_t *rwlock)
int readers;
_pthread_descr writer;
acquire (&rwlock->rw_spinlock);
__pthread_lock (&rwlock->rw_lock);
readers = rwlock->rw_readers;
writer = rwlock->rw_writer;
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
if (readers > 0 || writer != NULL)
return EBUSY;
@ -77,7 +76,7 @@ pthread_rwlock_rdlock (pthread_rwlock_t *rwlock)
while (1)
{
acquire (&rwlock->rw_spinlock);
__pthread_lock (&rwlock->rw_lock);
if (rwlock->rw_writer == NULL
|| (rwlock->rw_kind == PTHREAD_RWLOCK_PREFER_READER_NP
&& rwlock->rw_readers != 0))
@ -87,12 +86,12 @@ pthread_rwlock_rdlock (pthread_rwlock_t *rwlock)
/* Suspend ourselves, then try again */
self = thread_self ();
enqueue (&rwlock->rw_read_waiting, self);
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
suspend (self); /* This is not a cancellation point */
}
++rwlock->rw_readers;
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
return 0;
}
@ -103,7 +102,7 @@ pthread_rwlock_tryrdlock (pthread_rwlock_t *rwlock)
{
int result = EBUSY;
acquire (&rwlock->rw_spinlock);
__pthread_lock (&rwlock->rw_lock);
if (rwlock->rw_writer == NULL
|| (rwlock->rw_kind == PTHREAD_RWLOCK_PREFER_READER_NP
&& rwlock->rw_readers != 0))
@ -111,7 +110,7 @@ pthread_rwlock_tryrdlock (pthread_rwlock_t *rwlock)
++rwlock->rw_readers;
result = 0;
}
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
return result;
}
@ -124,17 +123,17 @@ pthread_rwlock_wrlock (pthread_rwlock_t *rwlock)
while(1)
{
acquire (&rwlock->rw_spinlock);
__pthread_lock (&rwlock->rw_lock);
if (rwlock->rw_readers == 0 && rwlock->rw_writer == NULL)
{
rwlock->rw_writer = self;
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
return 0;
}
/* Suspend ourselves, then try again */
enqueue (&rwlock->rw_write_waiting, self);
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
suspend (self); /* This is not a cancellation point */
}
}
@ -145,13 +144,13 @@ pthread_rwlock_trywrlock (pthread_rwlock_t *rwlock)
{
int result = EBUSY;
acquire (&rwlock->rw_spinlock);
__pthread_lock (&rwlock->rw_lock);
if (rwlock->rw_readers == 0 && rwlock->rw_writer == NULL)
{
rwlock->rw_writer = thread_self ();
result = 0;
}
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
return result;
}
@ -160,16 +159,16 @@ pthread_rwlock_trywrlock (pthread_rwlock_t *rwlock)
int
pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
{
struct _pthread_queue torestart;
pthread_descr torestart;
pthread_descr th;
acquire (&rwlock->rw_spinlock);
__pthread_lock (&rwlock->rw_lock);
if (rwlock->rw_writer != NULL)
{
/* Unlocking a write lock. */
if (rwlock->rw_writer != thread_self ())
{
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
return EPERM;
}
rwlock->rw_writer = NULL;
@ -179,15 +178,15 @@ pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
{
/* Restart all waiting readers. */
torestart = rwlock->rw_read_waiting;
queue_init (&rwlock->rw_read_waiting);
release (&rwlock->rw_spinlock);
rwlock->rw_read_waiting = NULL;
__pthread_unlock (&rwlock->rw_lock);
while ((th = dequeue (&torestart)) != NULL)
restart (th);
}
else
{
/* Restart one waiting writer. */
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
restart (th);
}
}
@ -196,7 +195,7 @@ pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
/* Unlocking a read lock. */
if (rwlock->rw_readers == 0)
{
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
return EPERM;
}
@ -207,7 +206,7 @@ pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
else
th = NULL;
release (&rwlock->rw_spinlock);
__pthread_unlock (&rwlock->rw_lock);
if (th != NULL)
restart (th);
}

232
linuxthreads/semaphore.c
View File

@ -17,69 +17,13 @@
#include "pthread.h"
#include "semaphore.h"
#include "internals.h"
#include "spinlock.h"
#include "restart.h"
#if !defined HAS_COMPARE_AND_SWAP && !defined TEST_FOR_COMPARE_AND_SWAP
/* If we have no atomic compare and swap, fake it using an extra spinlock. */
#include "spinlock.h"
static inline int sem_compare_and_swap(sem_t *sem, long oldval, long newval)
{
int ret;
acquire(&sem->sem_spinlock);
ret = (sem->sem_status == oldval);
if (ret) sem->sem_status = newval;
release(&sem->sem_spinlock);
return ret;
}
#elif defined TEST_FOR_COMPARE_AND_SWAP
#include "spinlock.h"
static int has_compare_and_swap = -1; /* to be determined at run-time */
static inline int sem_compare_and_swap(sem_t *sem, long oldval, long newval)
{
int ret;
if (has_compare_and_swap == 1)
return __compare_and_swap(&sem->sem_status, oldval, newval);
acquire(&sem->sem_spinlock);
ret = (sem->sem_status == oldval);
if (ret) sem->sem_status = newval;
release(&sem->sem_spinlock);
return ret;
}
#else
/* But if we do have an atomic compare and swap, use it! */
static inline int sem_compare_and_swap(sem_t *sem, long oldval, long newval)
{
return __compare_and_swap(&sem->sem_status, oldval, newval);
}
#endif
/* The state of a semaphore is represented by a long int encoding
either the semaphore count if >= 0 and no thread is waiting on it,
or the head of the list of threads waiting for the semaphore.
To distinguish the two cases, we encode the semaphore count N
as 2N+1, so that it has the lowest bit set.
A sequence of sem_wait operations on a semaphore initialized to N
result in the following successive states:
2N+1, 2N-1, ..., 3, 1, &first_waiting_thread, &second_waiting_thread, ...
*/
static void sem_restart_list(pthread_descr waiting);
#include "queue.h"
int sem_init(sem_t *sem, int pshared, unsigned int value)
{
if ((long)value > SEM_VALUE_MAX) {
if (value > SEM_VALUE_MAX) {
errno = EINVAL;
return -1;
}
@ -87,150 +31,104 @@ int sem_init(sem_t *sem, int pshared, unsigned int value)
errno = ENOSYS;
return -1;
}
#ifdef TEST_FOR_COMPARE_AND_SWAP
if (has_compare_and_swap == -1) {
has_compare_and_swap = compare_and_swap_is_available();
}
#endif
#if !defined HAS_COMPARE_AND_SWAP || defined TEST_FOR_COMPARE_AND_SWAP
sem->sem_spinlock = 0;
#endif
sem->sem_status = ((long)value << 1) + 1;
__pthread_init_lock((struct _pthread_fastlock *) &sem->sem_lock);
sem->sem_value = value;
sem->sem_waiting = NULL;
return 0;
}
int sem_wait(sem_t * sem)
{
long oldstatus, newstatus;
volatile pthread_descr self = thread_self();
pthread_descr * th;
volatile pthread_descr self;
while (1) {
do {
oldstatus = sem->sem_status;
if ((oldstatus & 1) && (oldstatus != 1))
newstatus = oldstatus - 2;
else {
newstatus = (long) self;
self->p_nextwaiting = (pthread_descr) oldstatus;
}
}
while (! sem_compare_and_swap(sem, oldstatus, newstatus));
if (newstatus & 1)
/* We got the semaphore. */
return 0;
/* Wait for sem_post or cancellation */
suspend_with_cancellation(self);
/* This is a cancellation point */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
/* Remove ourselves from the waiting list if we're still on it */
/* First check if we're at the head of the list. */
do {
oldstatus = sem->sem_status;
if (oldstatus != (long) self) break;
newstatus = (long) self->p_nextwaiting;
}
while (! sem_compare_and_swap(sem, oldstatus, newstatus));
/* Now, check if we're somewhere in the list.
There's a race condition with sem_post here, but it does not matter:
the net result is that at the time pthread_exit is called,
self is no longer reachable from sem->sem_status. */
if (oldstatus != (long) self && (oldstatus & 1) == 0) {
for (th = &(((pthread_descr) oldstatus)->p_nextwaiting);
*th != NULL && *th != (pthread_descr) 1;
th = &((*th)->p_nextwaiting)) {
if (*th == self) {
*th = self->p_nextwaiting;
break;
}
}
}
pthread_exit(PTHREAD_CANCELED);
}
__pthread_lock((struct _pthread_fastlock *) &sem->sem_lock);
if (sem->sem_value > 0) {
sem->sem_value--;
__pthread_unlock((struct _pthread_fastlock *) &sem->sem_lock);
return 0;
}
self = thread_self();
enqueue(&sem->sem_waiting, self);
/* Wait for sem_post or cancellation */
__pthread_unlock((struct _pthread_fastlock *) &sem->sem_lock);
suspend_with_cancellation(self);
/* This is a cancellation point */
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
/* Remove ourselves from the waiting list if we're still on it */
__pthread_lock((struct _pthread_fastlock *) &sem->sem_lock);
remove_from_queue(&sem->sem_waiting, self);
__pthread_unlock((struct _pthread_fastlock *) &sem->sem_lock);
pthread_exit(PTHREAD_CANCELED);
}
/* We got the semaphore */
return 0;
}
int sem_trywait(sem_t * sem)
{
long oldstatus, newstatus;
int retval;
do {
oldstatus = sem->sem_status;
if ((oldstatus & 1) == 0 || (oldstatus == 1)) {
errno = EAGAIN;
return -1;
}
newstatus = oldstatus - 2;
__pthread_lock((struct _pthread_fastlock *) &sem->sem_lock);
if (sem->sem_value == 0) {
errno = EAGAIN;
retval = -1;
} else {
sem->sem_value--;
retval = 0;
}
while (! sem_compare_and_swap(sem, oldstatus, newstatus));
return 0;
return retval;
}
int sem_post(sem_t * sem)
{
long oldstatus, newstatus;
pthread_descr self = thread_self();
pthread_descr th;
struct pthread_request request;
do {
oldstatus = sem->sem_status;
if ((oldstatus & 1) == 0)
newstatus = 3;
else {
if (oldstatus >= SEM_VALUE_MAX) {
if (self->p_in_sighandler == NULL) {
__pthread_lock((struct _pthread_fastlock *) &sem->sem_lock);
if (sem->sem_waiting == NULL) {
if (sem->sem_value >= SEM_VALUE_MAX) {
/* Overflow */
errno = ERANGE;
__pthread_unlock((struct _pthread_fastlock *) &sem->sem_lock);
return -1;
}
newstatus = oldstatus + 2;
sem->sem_value++;
__pthread_unlock((struct _pthread_fastlock *) &sem->sem_lock);
} else {
th = dequeue(&sem->sem_waiting);
__pthread_unlock((struct _pthread_fastlock *) &sem->sem_lock);
restart(th);
}
} else {
/* If we're in signal handler, delegate post operation to
the thread manager. */
if (__pthread_manager_request < 0) {
if (__pthread_initialize_manager() < 0) {
errno = EAGAIN;
return -1;
}
}
request.req_kind = REQ_POST;
request.req_args.post = sem;
__libc_write(__pthread_manager_request,
(char *) &request, sizeof(request));
}
while (! sem_compare_and_swap(sem, oldstatus, newstatus));
if ((oldstatus & 1) == 0)
sem_restart_list((pthread_descr) oldstatus);
return 0;
}
int sem_getvalue(sem_t * sem, int * sval)
{
long status = sem->sem_status;
if (status & 1)
*sval = (int)((unsigned long) status >> 1);
else
*sval = 0;
*sval = sem->sem_value;
return 0;
}
int sem_destroy(sem_t * sem)
{
if ((sem->sem_status & 1) == 0) {
if (sem->sem_waiting != NULL) {
errno = EBUSY;
return -1;
}
return 0;
}
/* Auxiliary function for restarting all threads on a waiting list,
in priority order. */
static void sem_restart_list(pthread_descr waiting)
{
pthread_descr th, towake, *p;
/* Sort list of waiting threads by decreasing priority (insertion sort) */
towake = NULL;
while (waiting != (pthread_descr) 1) {
th = waiting;
waiting = waiting->p_nextwaiting;
p = &towake;
while (*p != NULL && th->p_priority < (*p)->p_priority)
p = &((*p)->p_nextwaiting);
th->p_nextwaiting = *p;
*p = th;
}
/* Wake up threads in priority order */
while (towake != NULL) {
th = towake;
towake = towake->p_nextwaiting;
th->p_nextwaiting = NULL;
restart(th);
}
}

7
linuxthreads/semaphore.h
View File

@ -21,8 +21,11 @@
#define SEM_VALUE_MAX INT_MAX
/* Get the semaphore structure definition. */
#include <bits/semaphore.h>
typedef struct {
struct { long status; int spinlock; } sem_lock;
int sem_value;
_pthread_descr sem_waiting;
} sem_t;
__BEGIN_DECLS

89
linuxthreads/signals.c
View File

@ -53,83 +53,88 @@ int pthread_kill(pthread_t thread, int signo)
pthread_handle handle = thread_handle(thread);
int pid;
acquire(&handle->h_spinlock);
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread)) {
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
pid = handle->h_descr->p_pid;
release(&handle->h_spinlock);
__pthread_unlock(&handle->h_lock);
if (kill(pid, signo) == -1)
return errno;
else
return 0;
}
/* The set of signals on which some thread is doing a sigwait */
static sigset_t sigwaited;
static pthread_mutex_t sigwaited_mut = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t sigwaited_changed = PTHREAD_COND_INITIALIZER;
/* User-provided signal handlers */
static __sighandler_t sighandler[NSIG];
/* The wrapper around user-provided signal handlers */
static void pthread_sighandler(int signo)
{
pthread_descr self = thread_self();
char * in_sighandler;
/* If we're in a sigwait operation, just record the signal received
and return without calling the user's handler */
if (self->p_sigwaiting) {
self->p_sigwaiting = 0;
self->p_signal = signo;
return;
}
/* Record that we're in a signal handler and call the user's
handler function */
in_sighandler = self->p_in_sighandler;
if (in_sighandler == NULL) self->p_in_sighandler = CURRENT_STACK_FRAME;
sighandler[signo](signo);
if (in_sighandler == NULL) self->p_in_sighandler = NULL;
}
int sigaction(int sig, const struct sigaction * act,
struct sigaction * oact)
{
struct sigaction newact;
if (sig == PTHREAD_SIG_RESTART || sig == PTHREAD_SIG_CANCEL)
return EINVAL;
newact = *act;
if (act->sa_handler != SIG_IGN && act->sa_handler != SIG_DFL)
newact.sa_handler = pthread_sighandler;
if (__sigaction(sig, &newact, oact) == -1)
return -1;
if (oact != NULL) oact->sa_handler = sighandler[sig];
sighandler[sig] = act->sa_handler;
return 0;
}
int sigwait(const sigset_t * set, int * sig)
{
volatile pthread_descr self = thread_self();
sigset_t mask;
int s;
struct sigaction action, saved_signals[NSIG];
sigjmp_buf jmpbuf;
pthread_mutex_lock(&sigwaited_mut);
/* Make sure no other thread is waiting on our signals */
test_again:
for (s = 1; s < NSIG; s++) {
if (sigismember(set, s) && sigismember(&sigwaited, s)) {
pthread_cond_wait(&sigwaited_changed, &sigwaited_mut);
goto test_again;
}
}
/* Get ready to block all signals except those in set
and the cancellation signal */
sigfillset(&mask);
sigdelset(&mask, PTHREAD_SIG_CANCEL);
/* Signals in set are assumed blocked on entrance */
/* Install our signal handler on all signals in set,
and unblock them in mask.
Also mark those signals as being sigwaited on */
for (s = 1; s < NSIG; s++) {
if (sigismember(set, s) && s != PTHREAD_SIG_CANCEL) {
for (s = 1; s <= NSIG; s++) {
if (sigismember(set, s) && s != PTHREAD_SIG_CANCEL)
sigdelset(&mask, s);
action.sa_handler = __pthread_sighandler;
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
sigaction(s, &action, &(saved_signals[s]));
sigaddset(&sigwaited, s);
}
}
pthread_mutex_unlock(&sigwaited_mut);
/* Test for cancellation */
if (sigsetjmp(jmpbuf, 1) == 0) {
self->p_cancel_jmp = &jmpbuf;
if (! (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE)) {
/* Reset the signal count */
self->p_signal = 0;
/* Say we're in sigwait */
self->p_sigwaiting = 1;
/* Unblock the signals and wait for them */
sigsuspend(&mask);
}
}
self->p_cancel_jmp = NULL;
/* The signals are now reblocked. Restore the sighandlers. */
pthread_mutex_lock(&sigwaited_mut);
for (s = 1; s < NSIG; s++) {
if (sigismember(set, s) && s != PTHREAD_SIG_CANCEL) {
sigaction(s, &(saved_signals[s]), NULL);
sigdelset(&sigwaited, s);
}
}
pthread_cond_broadcast(&sigwaited_changed);
pthread_mutex_unlock(&sigwaited_mut);
/* Check for cancellation */
/* The signals are now reblocked. Check for cancellation */
pthread_testcancel();
/* We should have self->p_signal != 0 and equal to the signal received */
*sig = self->p_signal;

123
linuxthreads/spinlock.c
View File

@ -12,15 +12,130 @@
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
/* GNU Library General Public License for more details. */
/* Spin locks */
/* Internal locks */
#include <sched.h>
#include <time.h>
#include "pthread.h"
#include "internals.h"
#include "spinlock.h"
#include "restart.h"
/* This function is called if the inlined test-and-set in acquire() failed */
/* The status field of a fastlock has the following meaning:
0: fastlock is free
1: fastlock is taken, no thread is waiting on it
ADDR: fastlock is taken, ADDR is address of thread descriptor for
first waiting thread, other waiting threads are linked via
their p_nextwaiting field.
The waiting list is not sorted by priority order.
Actually, we always insert at top of list (sole insertion mode
that can be performed without locking).
For __pthread_unlock, we perform a linear search in the list
to find the highest-priority, oldest waiting thread.
This is safe because there are no concurrent __pthread_unlock
operations -- only the thread that locked the mutex can unlock it. */
void __pthread_lock(struct _pthread_fastlock * lock)
{
long oldstatus, newstatus;
pthread_descr self = NULL;
do {
oldstatus = lock->status;
if (oldstatus == 0) {
newstatus = 1;
} else {
self = thread_self();
self->p_nextwaiting = (pthread_descr) oldstatus;
newstatus = (long) self;
}
} while(! compare_and_swap(&lock->status, oldstatus, newstatus,
&lock->spinlock));
if (oldstatus != 0) suspend(self);
}
int __pthread_trylock(struct _pthread_fastlock * lock)
{
long oldstatus;
do {
oldstatus = lock->status;
if (oldstatus != 0) return EBUSY;
} while(! compare_and_swap(&lock->status, 0, 1, &lock->spinlock));
return 0;
}
void __pthread_unlock(struct _pthread_fastlock * lock)
{
long oldstatus;
pthread_descr thr, * ptr, * maxptr;
int maxprio;
again:
oldstatus = lock->status;
if (oldstatus == 1) {
/* No threads are waiting for this lock */
if (! compare_and_swap(&lock->status, 1, 0, &lock->spinlock)) goto again;
return;
}
/* Find thread in waiting queue with maximal priority */
ptr = (pthread_descr *) &lock->status;
thr = (pthread_descr) oldstatus;
maxprio = 0;
maxptr = ptr;
while (thr != (pthread_descr) 1) {
if (thr->p_priority >= maxprio) {
maxptr = ptr;
maxprio = thr->p_priority;
}
ptr = &(thr->p_nextwaiting);
thr = *ptr;
}
/* Remove max prio thread from waiting list. */
if (maxptr == (pthread_descr *) &lock->status) {
/* If max prio thread is at head, remove it with compare-and-swap
to guard against concurrent lock operation */
thr = (pthread_descr) oldstatus;
if (! compare_and_swap(&lock->status,
oldstatus, (long)(thr->p_nextwaiting),
&lock->spinlock))
goto again;
} else {
/* No risk of concurrent access, remove max prio thread normally */
thr = *maxptr;
*maxptr = thr->p_nextwaiting;
}
/* Wake up the selected waiting thread */
thr->p_nextwaiting = NULL;
restart(thr);
}
/* Compare-and-swap emulation with a spinlock */
#ifdef TEST_FOR_COMPARE_AND_SWAP
int __pthread_has_cas = 0;
#endif
#ifndef HAS_COMPARE_AND_SWAP
static void __pthread_acquire(int * spinlock);
int __pthread_compare_and_swap(long * ptr, long oldval, long newval,
int * spinlock)
{
int res;
if (testandset(spinlock)) __pthread_acquire(spinlock);
if (*ptr == oldval) {
*ptr = newval; res = 1;
} else {
res = 0;
}
*spinlock = 0;
return res;
}
/* This function is called if the inlined test-and-set
in __pthread_compare_and_swap() failed */
/* The retry strategy is as follows:
- We test and set the spinlock MAX_SPIN_COUNT times, calling
@ -40,7 +155,7 @@
- When nanosleep() returns, we try again, doing MAX_SPIN_COUNT
sched_yield(), then sleeping again if needed. */
void __pthread_acquire(int * spinlock)
static void __pthread_acquire(int * spinlock)
{
int cnt = 0;
struct timespec tm;
@ -57,3 +172,5 @@ void __pthread_acquire(int * spinlock)
}
}
}
#endif

53
linuxthreads/spinlock.h
View File

@ -1,7 +1,6 @@
/* Linuxthreads - a simple clone()-based implementation of Posix */
/* threads for Linux. */
/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) and */
/* Richard Henderson (rth@tamu.edu) */
/* Copyright (C) 1998 Xavier Leroy (Xavier.Leroy@inria.fr) */
/* */
/* This program is free software; you can redistribute it and/or */
/* modify it under the terms of the GNU Library General Public License */
@ -13,20 +12,52 @@
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
/* GNU Library General Public License for more details. */
/* Spin locks */
/* Internal locks */
extern void __pthread_acquire(int * spinlock);
extern void __pthread_lock(struct _pthread_fastlock * lock);
extern int __pthread_trylock(struct _pthread_fastlock * lock);
extern void __pthread_unlock(struct _pthread_fastlock * lock);
static inline void acquire(int * spinlock)
static inline void __pthread_init_lock(struct _pthread_fastlock * lock)
{
if (testandset(spinlock)) __pthread_acquire(spinlock);
lock->status = 0;
lock->spinlock = 0;
}
static inline void release(int * spinlock)
#define LOCK_INITIALIZER {0, 0}
#if defined(TEST_FOR_COMPARE_AND_SWAP)
extern int __pthread_has_cas;
extern int __pthread_compare_and_swap(long * ptr, long oldval, long newval,
int * spinlock);
static inline int compare_and_swap(long * ptr, long oldval, long newval,
int * spinlock)
{
#ifndef RELEASE
*spinlock = 0;
if (__pthread_has_cas)
return __compare_and_swap(ptr, oldval, newval);
else
return __pthread_compare_and_swap(ptr, oldval, newval, spinlock);
}
#elif defined(HAS_COMPARE_AND_SWAP)
static inline int compare_and_swap(long * ptr, long oldval, long newval,
int * spinlock)
{
return __compare_and_swap(ptr, oldval, newval);
}
#else
RELEASE(spinlock);
#endif
extern int __pthread_compare_and_swap(long * ptr, long oldval, long newval,
int * spinlock);
static inline int compare_and_swap(long * ptr, long oldval, long newval,
int * spinlock)
{
return __pthread_compare_and_swap(ptr, oldval, newval, spinlock);
}
#endif

6
linuxthreads/sysdeps/i386/pt-machine.h
View File

@ -1,6 +1,6 @@
/* Machine-dependent pthreads configuration and inline functions.
i386 version.
Copyright (C) 1996, 1997 Free Software Foundation, Inc.
Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>.
@ -45,7 +45,9 @@ register char * stack_pointer __asm__ ("%esp");
We test dynamically whether it's available or not. */
#define HAS_COMPARE_AND_SWAP
#define TEST_FOR_COMPARE_AND_SWAP
#ifndef __i686__
# define TEST_FOR_COMPARE_AND_SWAP
#endif
extern inline int
__compare_and_swap (long int *p, long int oldval, long int newval)

38
linuxthreads/sysdeps/pthread/pthread.h
View File

@ -43,21 +43,24 @@ typedef unsigned long int pthread_t;
/* Thread descriptors */
typedef struct _pthread_descr_struct *_pthread_descr;
/* Waiting queues (not abstract because mutexes and conditions aren't). */
struct _pthread_queue
/* Fast locks (not abstract because mutexes and conditions aren't abstract). */
struct _pthread_fastlock
{
_pthread_descr head; /* First element, or NULL if queue empty. */
_pthread_descr tail; /* Last element, or NULL if queue empty. */
long status; /* "Free" or "taken" or head of waiting list */
int spinlock; /* For compare-and-swap emulation */
};
/* Mutexes (not abstract because of PTHREAD_MUTEX_INITIALIZER). */
/* (The layout is unnatural to maintain binary compatibility
with earlier releases of LinuxThreads.) */
typedef struct
{
int m_spinlock; /* Spin lock to guarantee mutual exclusion. */
int m_count; /* 0 if free, > 0 if taken. */
_pthread_descr m_owner; /* Owner of mutex (for recursive mutexes) */
int m_kind; /* Kind of mutex */
struct _pthread_queue m_waiting; /* Threads waiting on this mutex. */
int m_reserved; /* Reserved for future use */
int m_count; /* Depth of recursive locking */
_pthread_descr m_owner; /* Owner thread (if recursive or errcheck) */
int m_kind; /* Mutex kind: fast, recursive or errcheck */
struct _pthread_fastlock m_lock; /* Underlying fast lock */
} pthread_mutex_t;
#define PTHREAD_MUTEX_INITIALIZER \
@ -68,21 +71,21 @@ typedef struct
/* Conditions (not abstract because of PTHREAD_COND_INITIALIZER */
typedef struct
{
int c_spinlock; /* Spin lock to protect the queue. */
struct _pthread_queue c_waiting; /* Threads waiting on this condition. */
struct _pthread_fastlock c_lock; /* Protect against concurrent access */
_pthread_descr c_waiting; /* Threads waiting on this condition */
} pthread_cond_t;
#define PTHREAD_COND_INITIALIZER {0, {0, 0}}
#define PTHREAD_COND_INITIALIZER {{0, 0}, 0}
#ifdef __USE_UNIX98
/* Read-write locks. */
typedef struct
{
int rw_spinlock; /* Spin lock to guarantee mutual exclusion */
struct _pthread_fastlock rw_lock; /* Lock to guarantee mutual exclusion */
int rw_readers; /* Number of readers */
_pthread_descr rw_writer; /* Identity of writer, or NULL if none */
struct _pthread_queue rw_read_waiting; /* Threads waiting for reading */
struct _pthread_queue rw_write_waiting; /* Threads waiting for writing */
_pthread_descr rw_read_waiting; /* Threads waiting for reading */
_pthread_descr rw_write_waiting; /* Threads waiting for writing */
int rw_kind; /* Reader/Writer preference selection */
int rw_pshared; /* Shared between processes or not */
} pthread_rwlock_t;
@ -231,7 +234,8 @@ extern int pthread_detach __P ((pthread_t __th));
/* Functions for handling attributes. */
/* Initialize thread attribute *ATTR with default attributes
(detachstate is PTHREAD_JOINABLE, scheduling policy is SCHED_OTHER). */
(detachstate is PTHREAD_JOINABLE, scheduling policy is SCHED_OTHER,
no user-provided stack). */
extern int pthread_attr_init __P ((pthread_attr_t *__attr));
/* Destroy thread attribute *ATTR. */
@ -288,6 +292,7 @@ extern int __pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr,
size_t *__guardsize));
extern int pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr,
size_t *__guardsize));
#endif
/* Set the starting address of the stack of the thread to be created.
Depending on whether the stack grows up or doen the value must either
@ -317,7 +322,6 @@ extern int __pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr,
size_t *__stacksize));
extern int pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr,
size_t *__stacksize));
#endif
/* Functions for scheduling control. */

8
linuxthreads/sysdeps/unix/sysv/linux/bits/posix_opt.h
View File

@ -1,5 +1,5 @@
/* Define POSIX options for Linux.
Copyright (C) 1996, 1997 Free Software Foundation, Inc.
Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@ -82,6 +82,12 @@
/* We provide priority scheduling for threads. */
#define _POSIX_THREAD_PRIORITY_SCHEDULING 1
/* We support user-defined stack sizes. */
#define _POSIX_THREAD_ATTR_STACKSIZE 1
/* We support user-defined stacks. */
#define _POSIX_THREAD_ATTR_STACKADDR 1
/* We support POSIX.1b semaphores, but only the non-shared form for now. */
/*#define _POSIX_SEMAPHORES 1 XXX We are not quite there now. */

7
sysdeps/unix/sysv/linux/bits/sched.h
View File

@ -1,6 +1,6 @@
/* Definitions of constants and data structure for POSIX 1003.1b-1993
scheduling interface.
Copyright (C) 1996, 1997 Free Software Foundation, Inc.
Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@ -38,10 +38,11 @@ struct sched_param
/* Cloning flags. */
# define CSIGNAL 0x000000ff /* Signal mask to be sent at exit. */
# define CLONE_VM 0x00000100 /* Set if VM shared between processes. */
# define CLONE_FS 0x00000200 /* Set if fs info shared between processes.*/
# define CLONE_FILES 0x00000400 /* Set if open files shared between processes*/
# define CLONE_FS 0x00000200 /* Set if fs info shared between processes. */
# define CLONE_FILES 0x00000400 /* Set if open files shared between processes. */
# define CLONE_SIGHAND 0x00000800 /* Set if signal handlers shared. */
# define CLONE_PID 0x00001000 /* Set if pid shared. */
# define CLONE_PTRACE 0x00002000 /* Set if tracing continues on the child. */
#endif