/* Init TLS for the initial thread. Called by the linker _before_ libc is mapped
* in memory. Beware: all writes to libc globals from this function will
* apply to linker-private copies and will not be visible from libc later on.
*
* Note: this function creates a pthread_internal_t for the initial thread and
* stores the pointer in TLS, but does not add it to pthread's thread list. This
* has to be done later from libc itself (see __libc_init_common).
*
* This function also stores a pointer to the kernel argument block in a TLS slot to be
* picked up by the libc constructor.
*/
void __libc_init_tls(KernelArgumentBlock& args) {
__libc_auxv = args.auxv;
static void* tls[BIONIC_TLS_SLOTS];
static pthread_internal_t main_thread;
main_thread.tls = tls;
// Tell the kernel to clear our tid field when we exit, so we're like any other pthread.
// As a side-effect, this tells us our pid (which is the same as the main thread's tid).
main_thread.tid = __set_tid_address(&main_thread.tid);
main_thread.set_cached_pid(main_thread.tid);
// Work out the extent of the main thread's stack.
uintptr_t stack_top = (__get_sp() & ~(PAGE_SIZE - 1)) + PAGE_SIZE;
size_t stack_size = get_main_thread_stack_size();
void* stack_bottom = reinterpret_cast<void*>(stack_top - stack_size);
// We don't want to free the main thread's stack even when the main thread exits
// because things like environment variables with global scope live on it.
pthread_attr_init(&main_thread.attr);
pthread_attr_setstack(&main_thread.attr, stack_bottom, stack_size);
main_thread.attr.flags = PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK | PTHREAD_ATTR_FLAG_MAIN_THREAD;
__init_thread(&main_thread, false);
__init_tls(&main_thread);
__set_tls(main_thread.tls);
tls[TLS_SLOT_BIONIC_PREINIT] = &args;
__init_alternate_signal_stack(&main_thread);
}
/* Init TLS for the initial thread. Called by the linker _before_ libc is mapped
* in memory. Beware: all writes to libc globals from this function will
* apply to linker-private copies and will not be visible from libc later on.
*
* Note: this function creates a pthread_internal_t for the initial thread and
* stores the pointer in TLS, but does not add it to pthread's gThreadList. This
* has to be done later from libc itself (see __libc_init_common).
*
* This function also stores a pointer to the kernel argument block in a TLS slot to be
* picked up by the libc constructor.
*/
void __libc_init_tls(KernelArgumentBlock& args) {
__libc_auxv = args.auxv;
uintptr_t stack_top = (__get_sp() & ~(PAGE_SIZE - 1)) + PAGE_SIZE;
size_t stack_size = get_main_thread_stack_size();
uintptr_t stack_bottom = stack_top - stack_size;
static void* tls[BIONIC_TLS_SLOTS];
static pthread_internal_t thread;
thread.tid = gettid();
thread.tls = tls;
pthread_attr_init(&thread.attr);
pthread_attr_setstack(&thread.attr, (void*) stack_bottom, stack_size);
_init_thread(&thread, false);
__init_tls(&thread);
tls[TLS_SLOT_BIONIC_PREINIT] = &args;
}
