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authorUlrich Drepper <drepper@redhat.com>1998-06-25 19:36:00 +0000
committerUlrich Drepper <drepper@redhat.com>1998-06-25 19:36:00 +0000
commit3387a425e65b839b68bd2973f6bc5ab22315cc5d (patch)
tree375713a0b865b10b9eddd9c9877ad68cf0bdc851 /linuxthreads/pthread.c
parentd47aac39992cb1dd705d8c584f4d3979d7ce4602 (diff)
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Finish user stack support. Change locking code to be safe in situations with different priorities.
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.
Diffstat (limited to 'linuxthreads/pthread.c')
-rw-r--r--linuxthreads/pthread.c89
1 files changed, 71 insertions, 18 deletions
diff --git a/linuxthreads/pthread.c b/linuxthreads/pthread.c
index 83d160622d..e95b352b72 100644
--- a/linuxthreads/pthread.c
+++ b/linuxthreads/pthread.c
@@ -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;