diff options
Diffstat (limited to 'linuxthreads/manager.c')
| -rw-r--r-- | linuxthreads/manager.c | 78 |
1 files changed, 60 insertions, 18 deletions
diff --git a/linuxthreads/manager.c b/linuxthreads/manager.c index 325955db4a..a650bbe4dd 100644 --- a/linuxthreads/manager.c +++ b/linuxthreads/manager.c @@ -172,27 +172,54 @@ static int pthread_start_thread(void *arg) } static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr, - void * (*start_routine)(void *), void *arg, - sigset_t * mask, int father_pid) + void * (*start_routine)(void *), void *arg, + sigset_t * mask, int father_pid) { size_t sseg; int pid; pthread_descr new_thread; pthread_t new_thread_id; int i; + void *guardaddr = NULL; /* Find a free stack segment for the current stack */ - for (sseg = 1; ; sseg++) { - if (sseg >= PTHREAD_THREADS_MAX) return EAGAIN; - if (__pthread_handles[sseg].h_descr != NULL) continue; - new_thread = thread_segment(sseg); - /* Allocate space for stack and thread descriptor. */ - if (mmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE), - INITIAL_STACK_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC, - MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED | MAP_GROWSDOWN, -1, 0) - != MAP_FAILED) break; - /* It seems part of this segment is already mapped. Try the next. */ - } + for (sseg = 1; ; sseg++) + { + if (sseg >= PTHREAD_THREADS_MAX) + return EAGAIN; + if (__pthread_handles[sseg].h_descr != NULL) + continue; + + if (attr == NULL || !attr->stackaddr_set) + { + new_thread = thread_segment(sseg); + /* Allocate space for stack and thread descriptor. */ + if (mmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE), + INITIAL_STACK_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED | MAP_GROWSDOWN, + -1, 0) != MAP_FAILED) + { + /* We manage to get a stack. Now see whether we need a guard + and allocate it if necessary. */ + if (attr->guardsize != 0) + { + guardaddr = mmap ((caddr_t)((char *)(new_thread+1) + - 2*1024*1024), + attr->guardsize, 0, MAP_FIXED, -1, 0); + if (guardaddr == MAP_FAILED) + /* We don't make this an error. */ + guardaddr = NULL; + } + break; + } + /* It seems part of this segment is already mapped. Try the next. */ + } + else + { + new_thread = (pthread_descr) attr->stackaddr - 1; + break; + } + } /* Allocate new thread identifier */ pthread_threads_counter += PTHREAD_THREADS_MAX; new_thread_id = sseg + pthread_threads_counter; @@ -217,6 +244,10 @@ 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_guardaddr = guardaddr; + new_thread->p_guardsize = (attr == NULL || !attr->stackaddr_set + ? attr->guardsize : 0); + new_thread->p_userstack = attr != NULL && attr->stackaddr_set; for (i = 0; i < PTHREAD_KEY_1STLEVEL_SIZE; i++) new_thread->p_specific[i] = NULL; /* Initialize the thread handle */ @@ -249,9 +280,14 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr, new_thread); /* Check if cloning succeeded */ if (pid == -1) { - /* Free the stack */ - munmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE), - INITIAL_STACK_SIZE); + /* Free the stack if we allocated it */ + if (attr == NULL || !attr->stackaddr_set) + { + munmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE), + INITIAL_STACK_SIZE); + if (attr->guardsize != 0) + munmap(new_thread->p_guardaddr, new_thread->p_guardsize); + } __pthread_handles[sseg].h_descr = NULL; return errno; } @@ -268,6 +304,7 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr, return 0; } + /* Free the resources of a thread. */ static void pthread_free(pthread_descr th) @@ -281,8 +318,13 @@ static void pthread_free(pthread_descr th) release(&handle->h_spinlock); /* If initial thread, nothing to free */ if (th == &__pthread_initial_thread) return; - /* Free the stack and thread descriptor area */ - munmap((caddr_t) ((char *)(th+1) - STACK_SIZE), STACK_SIZE); + if (!th->p_userstack) + { + /* Free the stack and thread descriptor area */ + munmap((caddr_t) ((char *)(th+1) - STACK_SIZE), STACK_SIZE); + if (th->p_guardsize != 0) + munmap(th->p_guardaddr, th->p_guardsize); + } } /* Handle threads that have exited */ |