glibc/sysdeps/nptl/dl-tls_init_tp.c
Adhemerval Zanella Netto 33237fe83d Remove --enable-tunables configure option
And make always supported.  The configure option was added on glibc 2.25
and some features require it (such as hwcap mask, huge pages support, and
lock elisition tuning).  It also simplifies the build permutations.

Changes from v1:
 * Remove glibc.rtld.dynamic_sort changes, it is orthogonal and needs
   more discussion.
 * Cleanup more code.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-03-29 14:33:06 -03:00

130 lines
4.1 KiB
C

/* Completion of TCB initialization after TLS_INIT_TP. NPTL version.
Copyright (C) 2020-2023 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 <pthreadP.h>
#include <tls.h>
#include <rseq-internal.h>
#include <thread_pointer.h>
#define TUNABLE_NAMESPACE pthread
#include <dl-tunables.h>
#ifndef __ASSUME_SET_ROBUST_LIST
bool __nptl_set_robust_list_avail;
rtld_hidden_data_def (__nptl_set_robust_list_avail)
#endif
bool __nptl_initial_report_events;
rtld_hidden_def (__nptl_initial_report_events)
#ifdef SHARED
/* Dummy implementation. See __rtld_mutex_init. */
static int
rtld_mutex_dummy (pthread_mutex_t *lock)
{
return 0;
}
#endif
const unsigned int __rseq_flags;
const unsigned int __rseq_size attribute_relro;
const ptrdiff_t __rseq_offset attribute_relro;
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)
{
struct pthread *pd = THREAD_SELF;
/* Set up thread stack list management. */
list_add (&pd->list, &GL (dl_stack_user));
/* Early initialization of the TCB. */
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);
/* Before initializing GL (dl_stack_user), the debugger could not
find us and had to set __nptl_initial_report_events. Propagate
its setting. */
THREAD_SETMEM (pd, report_events, __nptl_initial_report_events);
/* 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
}
}
{
bool do_rseq = true;
do_rseq = TUNABLE_GET (rseq, int, NULL);
if (rseq_register_current_thread (pd, do_rseq))
{
/* We need a writable view of the variables. They are in
.data.relro and are not yet write-protected. */
extern unsigned int size __asm__ ("__rseq_size");
size = sizeof (pd->rseq_area);
}
#ifdef RSEQ_SIG
/* This should be a compile-time constant, but the current
infrastructure makes it difficult to determine its value. Not
all targets support __thread_pointer, so set __rseq_offset only
if thre rseq registration may have happened because RSEQ_SIG is
defined. */
extern ptrdiff_t offset __asm__ ("__rseq_offset");
offset = (char *) &pd->rseq_area - (char *) __thread_pointer ();
#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);
}