glibc/sysdeps/nptl/dl-tls_init_tp.c
Florian Weimer 9d124d81f0 nptl: Move more stack management variables into _rtld_global
Permissions of the cached stacks may have to be updated if an object
is loaded that requires executable stacks, so the dynamic loader
needs to know about these cached stacks.

The move of in_flight_stack and stack_cache_actsize is a requirement for
merging __reclaim_stacks into the fork implementation in libc.

Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-10 10:31:41 +02:00

90 lines
2.8 KiB
C

/* Completion of TCB initialization after TLS_INIT_TP. NPTL version.
Copyright (C) 2020-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <kernel-features.h>
#include <ldsodefs.h>
#include <list.h>
#include <nptl/pthreadP.h>
#include <tls.h>
#ifndef __ASSUME_SET_ROBUST_LIST
bool __nptl_set_robust_list_avail __attribute__ ((nocommon));
rtld_hidden_data_def (__nptl_set_robust_list_avail)
#endif
#ifdef SHARED
/* Dummy implementation. See __rtld_mutex_init. */
static int
rtld_mutex_dummy (pthread_mutex_t *lock)
{
return 0;
}
#endif
void
__tls_pre_init_tp (void)
{
/* The list data structures are not consistent until
initialized. */
INIT_LIST_HEAD (&GL (dl_stack_used));
INIT_LIST_HEAD (&GL (dl_stack_user));
INIT_LIST_HEAD (&GL (dl_stack_cache));
#ifdef SHARED
___rtld_mutex_lock = rtld_mutex_dummy;
___rtld_mutex_unlock = rtld_mutex_dummy;
#endif
}
void
__tls_init_tp (void)
{
/* Set up thread stack list management. */
list_add (&THREAD_SELF->list, &GL (dl_stack_user));
/* Early initialization of the TCB. */
struct pthread *pd = THREAD_SELF;
pd->tid = INTERNAL_SYSCALL_CALL (set_tid_address, &pd->tid);
THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]);
THREAD_SETMEM (pd, user_stack, true);
/* Initialize the robust mutex data. */
{
#if __PTHREAD_MUTEX_HAVE_PREV
pd->robust_prev = &pd->robust_head;
#endif
pd->robust_head.list = &pd->robust_head;
pd->robust_head.futex_offset = (offsetof (pthread_mutex_t, __data.__lock)
- offsetof (pthread_mutex_t,
__data.__list.__next));
int res = INTERNAL_SYSCALL_CALL (set_robust_list, &pd->robust_head,
sizeof (struct robust_list_head));
if (!INTERNAL_SYSCALL_ERROR_P (res))
{
#ifndef __ASSUME_SET_ROBUST_LIST
__nptl_set_robust_list_avail = true;
#endif
}
}
/* Set initial thread's stack block from 0 up to __libc_stack_end.
It will be bigger than it actually is, but for unwind.c/pt-longjmp.c
purposes this is good enough. */
THREAD_SETMEM (pd, stackblock_size, (size_t) __libc_stack_end);
}