diff options
Diffstat (limited to 'lib/libpthread/thread')
| -rw-r--r-- | lib/libpthread/thread/thr_kern.c | 7 | ||||
| -rw-r--r-- | lib/libpthread/thread/thr_kill.c | 94 | ||||
| -rw-r--r-- | lib/libpthread/thread/thr_private.h | 4 | ||||
| -rw-r--r-- | lib/libpthread/thread/thr_sig.c | 248 | ||||
| -rw-r--r-- | lib/libpthread/thread/thr_wait4.c | 2 |
5 files changed, 208 insertions, 147 deletions
diff --git a/lib/libpthread/thread/thr_kern.c b/lib/libpthread/thread/thr_kern.c index cdb84a5..f69cb41 100644 --- a/lib/libpthread/thread/thr_kern.c +++ b/lib/libpthread/thread/thr_kern.c @@ -1076,6 +1076,7 @@ dequeue_signals(void) { char bufr[128]; int i, num; + pthread_t pthread; /* * Enter a loop to read and handle queued signals from the @@ -1096,7 +1097,11 @@ dequeue_signals(void) } else { /* Handle this signal: */ - _thread_sig_handle((int) bufr[i], NULL); + pthread = _thread_sig_handle((int) bufr[i], + NULL); + if (pthread != NULL) + _thread_sig_deliver(pthread, + (int) bufr[i]); } } } diff --git a/lib/libpthread/thread/thr_kill.c b/lib/libpthread/thread/thr_kill.c index 6b25550..4bf1761 100644 --- a/lib/libpthread/thread/thr_kill.c +++ b/lib/libpthread/thread/thr_kill.c @@ -46,7 +46,6 @@ pthread_kill(pthread_t pthread, int sig) if (sig < 0 || sig >= NSIG) /* Invalid signal: */ ret = EINVAL; - /* * Ensure the thread is in the list of active threads, and the * signal is valid (signal 0 specifies error checking only) and @@ -60,98 +59,7 @@ pthread_kill(pthread_t pthread, int sig) */ _thread_kern_sig_defer(); - switch (pthread->state) { - case PS_SIGSUSPEND: - /* - * Only wake up the thread if the signal is unblocked - * and there is a handler installed for the signal. - */ - if (!sigismember(&pthread->sigmask, sig) && - _thread_sigact[sig - 1].sa_handler != SIG_DFL) { - /* Change the state of the thread to run: */ - PTHREAD_NEW_STATE(pthread,PS_RUNNING); - - /* Return the signal number: */ - pthread->signo = sig; - } - /* Increment the pending signal count: */ - sigaddset(&pthread->sigpend,sig); - break; - - case PS_SIGWAIT: - /* Wake up the thread if the signal is blocked. */ - if (sigismember(pthread->data.sigwait, sig)) { - /* Change the state of the thread to run: */ - PTHREAD_NEW_STATE(pthread,PS_RUNNING); - - /* Return the signal number: */ - pthread->signo = sig; - } else - /* Increment the pending signal count. */ - sigaddset(&pthread->sigpend,sig); - break; - - case PS_FDR_WAIT: - case PS_FDW_WAIT: - case PS_POLL_WAIT: - case PS_SLEEP_WAIT: - case PS_SELECT_WAIT: - if (!sigismember(&pthread->sigmask, sig) && - (_thread_sigact[sig - 1].sa_handler != SIG_IGN)) { - /* Flag the operation as interrupted: */ - pthread->interrupted = 1; - - if (pthread->flags & PTHREAD_FLAGS_IN_WORKQ) - PTHREAD_WORKQ_REMOVE(pthread); - - /* Change the state of the thread to run: */ - PTHREAD_NEW_STATE(pthread,PS_RUNNING); - - /* Return the signal number: */ - pthread->signo = sig; - } else { - /* Increment the pending signal count: */ - sigaddset(&pthread->sigpend,sig); - } - break; - - default: - /* Increment the pending signal count: */ - sigaddset(&pthread->sigpend,sig); - break; - } - - - /* - * Check that a custom handler is installed - * and if the signal is not blocked: - */ - if (_thread_sigact[sig - 1].sa_handler != SIG_DFL && - _thread_sigact[sig - 1].sa_handler != SIG_IGN && - sigismember(&pthread->sigpend, sig) && - !sigismember(&pthread->sigmask, sig)) { - pthread_t pthread_saved = _thread_run; - - /* Current thread inside critical region? */ - if (_thread_run->sig_defer_count > 0) - pthread->sig_defer_count++; - - _thread_run = pthread; - - /* Clear the pending signal: */ - sigdelset(&pthread->sigpend, sig); - - /* - * Dispatch the signal via the custom signal - * handler: - */ - (*(_thread_sigact[sig - 1].sa_handler))(sig); - - _thread_run = pthread_saved; - - if (_thread_run->sig_defer_count > 0) - pthread->sig_defer_count--; - } + _thread_sig_send(pthread, sig); /* * Undefer and handle pending signals, yielding if diff --git a/lib/libpthread/thread/thr_private.h b/lib/libpthread/thread/thr_private.h index 70c7487..4326bf6 100644 --- a/lib/libpthread/thread/thr_private.h +++ b/lib/libpthread/thread/thr_private.h @@ -984,8 +984,10 @@ void _thread_kern_set_timeout(struct timespec *); void _thread_kern_sig_defer(void); void _thread_kern_sig_undefer(void); void _thread_sig_handler(int, int, ucontext_t *); -void _thread_sig_handle(int, ucontext_t *); +pthread_t _thread_sig_handle(int, ucontext_t *); void _thread_sig_init(void); +void _thread_sig_send(pthread_t pthread, int sig); +void _thread_sig_deliver(pthread_t pthread, int sig); void _thread_start(void); void _thread_start_sig_handler(void); void _thread_seterrno(pthread_t,int); diff --git a/lib/libpthread/thread/thr_sig.c b/lib/libpthread/thread/thr_sig.c index 3830a1d..b744659 100644 --- a/lib/libpthread/thread/thr_sig.c +++ b/lib/libpthread/thread/thr_sig.c @@ -43,13 +43,13 @@ #include "pthread_private.h" /* Prototypes: */ -static void _thread_signal(pthread_t pthread, int sig); +static void _thread_sig_check_state(pthread_t pthread, int sig); /* Static variables: */ static spinlock_t signal_lock = _SPINLOCK_INITIALIZER; -unsigned int pending_sigs[NSIG]; -unsigned int handled_sigs[NSIG]; -int volatile check_pending = 0; +static unsigned int pending_sigs[NSIG]; +static unsigned int handled_sigs[NSIG]; +static int volatile check_pending = 0; /* Initialize signal handling facility: */ void @@ -73,8 +73,9 @@ _thread_sig_init(void) void _thread_sig_handler(int sig, int code, ucontext_t * scp) { - char c; + pthread_t pthread; int i; + char c; /* Check if an interval timer signal: */ if (sig == _SCHED_SIGNAL) { @@ -134,13 +135,20 @@ _thread_sig_handler(int sig, int code, ucontext_t * scp) } else { /* It's safe to handle the signal now. */ - _thread_sig_handle(sig, scp); + pthread = _thread_sig_handle(sig, scp); /* Reset the pending and handled count back to 0: */ pending_sigs[sig - 1] = 0; handled_sigs[sig - 1] = 0; - signal_lock.access_lock = 0; + if (pthread == NULL) + signal_lock.access_lock = 0; + else { + sigaddset(&pthread->sigmask, sig); + signal_lock.access_lock = 0; + _thread_sig_deliver(pthread, sig); + sigdelset(&pthread->sigmask, sig); + } } /* Enter a loop to process pending signals: */ @@ -148,15 +156,27 @@ _thread_sig_handler(int sig, int code, ucontext_t * scp) (_atomic_lock(&signal_lock.access_lock) == 0)) { check_pending = 0; for (i = 1; i < NSIG; i++) { - if (pending_sigs[i - 1] > handled_sigs[i - 1]) - _thread_sig_handle(i, scp); + if (pending_sigs[i - 1] > handled_sigs[i - 1]) { + pending_sigs[i - 1] = handled_sigs[i - 1]; + pthread = _thread_sig_handle(i, scp); + if (pthread != NULL) { + sigaddset(&pthread->sigmask, i); + signal_lock.access_lock = 0; + _thread_sig_deliver(pthread, i); + sigdelset(&pthread->sigmask, i); + if (_atomic_lock(&signal_lock.access_lock)) { + check_pending = 1; + return; + } + } + } } signal_lock.access_lock = 0; } } } -void +pthread_t _thread_sig_handle(int sig, ucontext_t * scp) { int i; @@ -193,6 +213,30 @@ _thread_sig_handle(int sig, ucontext_t * scp) O_NONBLOCK); } } + /* + * Enter a loop to wake up all threads waiting + * for a process to complete: + */ + for (pthread = TAILQ_FIRST(&_waitingq); + pthread != NULL; pthread = pthread_next) { + /* + * Grab the next thread before possibly + * destroying the link entry: + */ + pthread_next = TAILQ_NEXT(pthread, pqe); + + /* + * If this thread is waiting for a child + * process to complete, wake it up: + */ + if (pthread->state == PS_WAIT_WAIT) { + /* Make the thread runnable: */ + PTHREAD_NEW_STATE(pthread,PS_RUNNING); + + /* Return the signal number: */ + pthread->signo = sig; + } + } } /* @@ -244,7 +288,7 @@ _thread_sig_handle(int sig, ucontext_t * scp) * Do not attempt to deliver this signal * to other threads. */ - return; + return (NULL); } else if (!sigismember(&pthread->sigmask, sig)) { if (pthread->state == PS_SIGSUSPEND) { @@ -255,6 +299,23 @@ _thread_sig_handle(int sig, ucontext_t * scp) } } + /* + * If we didn't find a thread in the waiting queue, + * check the all threads queue: + */ + if (suspended_thread == NULL && signaled_thread == NULL) { + /* + * Enter a loop to look for other threads capable + * of receiving the signal: + */ + TAILQ_FOREACH(pthread, &_thread_list, tle) { + if (!sigismember(&pthread->sigmask, sig)) { + signaled_thread = pthread; + break; + } + } + } + /* Check if the signal is not being ignored: */ if (_thread_sigact[sig - 1].sa_handler != SIG_IGN) { if (suspended_thread == NULL && @@ -265,8 +326,6 @@ _thread_sig_handle(int sig, ucontext_t * scp) */ sigaddset(&_process_sigpending, sig); else { - pthread_t pthread_saved = _thread_run; - /* * We only deliver the signal to one thread; * give preference to the suspended thread: @@ -276,42 +335,25 @@ _thread_sig_handle(int sig, ucontext_t * scp) else pthread = signaled_thread; - /* Current thread inside critical region? */ - if (_thread_run->sig_defer_count > 0) - pthread->sig_defer_count++; - - _thread_run = pthread; - _thread_signal(pthread,sig); - /* - * Dispatch pending signals to the - * running thread: + * Perform any state changes due to signal + * arrival: */ - _dispatch_signals(); - _thread_run = pthread_saved; - - /* Current thread inside critical region? */ - if (_thread_run->sig_defer_count > 0) - pthread->sig_defer_count--; + _thread_sig_check_state(pthread, sig); + return (pthread); } - } } /* Returns nothing. */ - return; + return (NULL); } /* Perform thread specific actions in response to a signal: */ static void -_thread_signal(pthread_t pthread, int sig) +_thread_sig_check_state(pthread_t pthread, int sig) { /* - * Flag the signal as pending. It will be dispatched later. - */ - sigaddset(&pthread->sigpend,sig); - - /* * Process according to thread state: */ switch (pthread->state) { @@ -329,12 +371,26 @@ _thread_signal(pthread_t pthread, int sig) case PS_RUNNING: case PS_STATE_MAX: case PS_SIGTHREAD: - case PS_SIGWAIT: case PS_SPINBLOCK: case PS_SUSPENDED: - /* Nothing to do here. */ + /* Increment the pending signal count. */ + sigaddset(&pthread->sigpend,sig); break; + case PS_SIGWAIT: + /* Wake up the thread if the signal is blocked. */ + if (sigismember(pthread->data.sigwait, sig)) { + /* Change the state of the thread to run: */ + PTHREAD_NEW_STATE(pthread,PS_RUNNING); + + /* Return the signal number: */ + pthread->signo = sig; + } else + /* Increment the pending signal count. */ + sigaddset(&pthread->sigpend,sig); + break; + + /* * The wait state is a special case due to the handling of * SIGCHLD signals. @@ -364,9 +420,7 @@ _thread_signal(pthread_t pthread, int sig) case PS_POLL_WAIT: case PS_SLEEP_WAIT: case PS_SELECT_WAIT: - if ((_thread_sigact[sig - 1].sa_flags & SA_RESTART) == 0 && - (sig != SIGCHLD || - _thread_sigact[sig - 1].sa_handler != SIG_DFL)) { + if ((_thread_sigact[sig - 1].sa_flags & SA_RESTART) == 0) { /* Flag the operation as interrupted: */ pthread->interrupted = 1; @@ -397,11 +451,41 @@ _thread_signal(pthread_t pthread, int sig) } } +/* Send a signal to a specific thread (ala pthread_kill): */ +void +_thread_sig_send(pthread_t pthread, int sig) +{ + /* + * Check that the signal is not being ignored: + */ + if (_thread_sigact[sig - 1].sa_handler != SIG_IGN) { + if (pthread->state == PS_SIGWAIT && + sigismember(pthread->data.sigwait, sig)) { + /* Change the state of the thread to run: */ + PTHREAD_NEW_STATE(pthread,PS_RUNNING); + + /* Return the signal number: */ + pthread->signo = sig; + } else if (pthread->state != PS_SIGWAIT && + !sigismember(&pthread->sigmask, sig)) { + /* Perform any state changes due to signal arrival: */ + _thread_sig_check_state(pthread, sig); + + /* Call the installed signal handler: */ + _thread_sig_deliver(pthread, sig); + } + else { + /* Increment the pending signal count. */ + sigaddset(&pthread->sigpend,sig); + } + } +} + /* Dispatch pending signals to the running thread: */ void _dispatch_signals() { - sigset_t sigset; + sigset_t sigset, mask; int i; /* @@ -411,9 +495,16 @@ _dispatch_signals() sigset = _thread_run->sigpend; SIGSETOR(sigset, _process_sigpending); SIGSETNAND(sigset, _thread_run->sigmask); - if (SIGNOTEMPTY(sigset)) - /* Look for all possible pending signals: */ - for (i = 1; i < NSIG; i++) + if (SIGNOTEMPTY(sigset)) { + /* + * Enter a loop to calculate deliverable pending signals + * before actually delivering them. The pending signals + * must be removed from the pending signal sets before + * calling the signal handler because the handler may + * call library routines that again check for and deliver + * pending signals. + */ + for (i = 1; i < NSIG; i++) { /* * Check that a custom handler is installed * and if the signal is not blocked: @@ -427,12 +518,67 @@ _dispatch_signals() else /* Clear the process pending signal: */ sigdelset(&_process_sigpending,i); - - /* - * Dispatch the signal via the custom signal - * handler: - */ - (*(_thread_sigact[i - 1].sa_handler))(i); } + else + /* Remove the signal if it can't be handled: */ + sigdelset(&sigset, i); + } + + /* Now deliver the signals: */ + for (i = 1; i < NSIG; i++) { + if (sigismember(&sigset, i)) + /* Deliver the signal to the running thread: */ + _thread_sig_deliver(_thread_run, i); + } + } +} + +/* Deliver a signal to a thread: */ +void +_thread_sig_deliver(pthread_t pthread, int sig) +{ + sigset_t mask; + pthread_t pthread_saved; + + /* + * Check that a custom handler is installed + * and if the signal is not blocked: + */ + if (_thread_sigact[sig - 1].sa_handler != SIG_DFL && + _thread_sigact[sig - 1].sa_handler != SIG_IGN) { + /* Save the current thread: */ + pthread_saved = _thread_run; + + /* Save the threads signal mask: */ + mask = pthread->sigmask; + + /* + * Add the current signal and signal handler + * mask to the threads current signal mask: + */ + SIGSETOR(pthread->sigmask, _thread_sigact[sig - 1].sa_mask); + sigaddset(&pthread->sigmask, sig); + + /* Current thread inside critical region? */ + if (_thread_run->sig_defer_count > 0) + pthread->sig_defer_count++; + + _thread_run = pthread; + + /* + * Dispatch the signal via the custom signal + * handler: + */ + (*(_thread_sigact[sig - 1].sa_handler))(sig); + + _thread_run = pthread_saved; + + /* Current thread inside critical region? */ + if (_thread_run->sig_defer_count > 0) + pthread->sig_defer_count--; + + /* Restore the threads signal mask: */ + pthread->sigmask = mask; + } } #endif diff --git a/lib/libpthread/thread/thr_wait4.c b/lib/libpthread/thread/thr_wait4.c index baa697c..4a58a70 100644 --- a/lib/libpthread/thread/thr_wait4.c +++ b/lib/libpthread/thread/thr_wait4.c @@ -40,7 +40,7 @@ pid_t wait4(pid_t pid, int *istat, int options, struct rusage * rusage) { - pid_t ret; + pid_t ret; _thread_enter_cancellation_point(); _thread_kern_sig_defer(); |
