diff options
Diffstat (limited to 'linuxthreads/manager.c')
| -rw-r--r-- | linuxthreads/manager.c | 57 |
1 files changed, 30 insertions, 27 deletions
diff --git a/linuxthreads/manager.c b/linuxthreads/manager.c index 1139e2eca7..b76203c505 100644 --- a/linuxthreads/manager.c +++ b/linuxthreads/manager.c @@ -41,9 +41,11 @@ struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX] = /* For debugging purposes put the maximum number of threads in a variable. */ const int __linuxthreads_pthread_threads_max = PTHREAD_THREADS_MAX; +#ifndef THREAD_SELF /* 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; +#endif /* Number of active entries in __pthread_handles (used by gdb) */ volatile int __pthread_handles_num = 2; @@ -319,9 +321,11 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, new_thread = (pthread_descr) ((long)(attr->__stackaddr) & -sizeof(void *)) - 1; new_thread_bottom = (char *) attr->__stackaddr - attr->__stacksize; - guardaddr = NULL; + guardaddr = new_thread_bottom; guardsize = 0; +#ifndef THREAD_SELF __pthread_nonstandard_stacks = 1; +#endif } else { @@ -331,6 +335,8 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, #else size_t granularity = pagesize; #endif + void *map_addr; + /* Allocate space for stack and thread descriptor at default address */ if (attr != NULL) { @@ -344,8 +350,8 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, guardsize = granularity; stacksize = STACK_SIZE - granularity; } - new_thread = default_new_thread; #ifdef NEED_SEPARATE_REGISTER_STACK + new_thread = default_new_thread; new_thread_bottom = (char *) (new_thread + 1) - stacksize - guardsize; /* Includes guard area, unlike the normal case. Use the bottom end of the segment as backing store for the register stack. @@ -376,11 +382,12 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, guardaddr = new_thread_bottom + stacksize/2; /* We leave the guard area in the middle unmapped. */ #else /* !NEED_SEPARATE_REGISTER_STACK */ + new_thread = default_new_thread; new_thread_bottom = (char *) (new_thread + 1) - stacksize; - 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) + map_addr = mmap((caddr_t)((char *)(new_thread + 1) - stacksize), + stacksize, PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0); + if (map_addr == MAP_FAILED) /* Bad luck, this segment is already mapped. */ return -1; /* We manage to get a stack. Now see whether we need a guard @@ -391,7 +398,7 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, if (stacksize == STACK_SIZE - pagesize) { /* We don't need a guard page. */ - guardaddr = NULL; + guardaddr = new_thread_bottom; guardsize = 0; } else @@ -402,7 +409,7 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, == MAP_FAILED) { /* We don't make this an error. */ - guardaddr = NULL; + guardaddr = new_thread_bottom; guardsize = 0; } } @@ -445,7 +452,8 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr, return EAGAIN; if (__pthread_handles[sseg].h_descr != NULL) continue; - if (pthread_allocate_stack(attr, thread_segment(sseg), pagesize, + if (pthread_allocate_stack(attr, thread_segment(sseg), + pagesize, &new_thread, &new_thread_bottom, &guardaddr, &guardsize) == 0) break; @@ -589,14 +597,11 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr, #ifdef NEED_SEPARATE_REGISTER_STACK size_t stacksize = ((char *)(new_thread->p_guardaddr) - new_thread_bottom); - munmap((caddr_t)new_thread_bottom, stacksize); - munmap((caddr_t)new_thread_bottom + stacksize - + new_thread->p_guardsize, stacksize); + munmap((caddr_t)new_thread_bottom, + 2 * stacksize + new_thread->p_guardsize); #else - if (new_thread->p_guardsize != 0) - munmap(new_thread->p_guardaddr, new_thread->p_guardsize); - munmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE), - INITIAL_STACK_SIZE); + size_t stacksize = (char *)(new_thread+1) - new_thread_bottom; + munmap(new_thread_bottom - guardsize, guardsize + stacksize); #endif } __pthread_handles[sseg].h_descr = NULL; @@ -654,7 +659,6 @@ static void pthread_free(pthread_descr th) } /* If initial thread, nothing to free */ - if (th == &__pthread_initial_thread) return; if (!th->p_userstack) { size_t guardsize = th->p_guardsize; @@ -666,17 +670,16 @@ static void pthread_free(pthread_descr th) guardsize is 0. This allows us to compute everything else. */ size_t stacksize = (char *)(th+1) - guardaddr - guardsize; /* Unmap the register stack, which is below guardaddr. */ - munmap((caddr_t)(guardaddr-stacksize), stacksize); - /* Unmap the main stack. */ - munmap((caddr_t)(guardaddr+guardsize), stacksize); + munmap((caddr_t)(guardaddr-stacksize), + 2 * stacksize + th->p_guardsize); #else - /* The following assumes that we only allocate stacks of one - size. That's currently true but probably shouldn't be. This - looks like it fails for growing stacks if there was something - else mapped just below the stack? */ - if (guardsize != 0) - munmap(th->p_guardaddr, guardsize); - munmap((caddr_t) ((char *)(th+1) - STACK_SIZE), STACK_SIZE); + char *guardaddr = th->p_guardaddr; + /* We unmap exactly what we mapped, in case there was something + else in the same region. Guardaddr is always set, eve if + guardsize is 0. This allows us to compute everything else. */ + size_t stacksize = (char *)(th+1) - guardaddr - guardsize; + + munmap (guardaddr, stacksize + guardsize); #endif } } |