glibc/nptl/tst-tls7mod.c
Andrew Hunter 7f507ee17a Async-signal safe TLS.
ChangeLog:

2014-01-03  Andrew Hunter  <ahh@google.com>

	* elf/dl-open.c (): New comment.
	* elf/dl-reloc.c (_dl_try_allocate_static_tls): Use
	atomic_compare_and_exchange_bool_acq
	(_dl_allocate_static_tls): Block signals.
	* elf/dl-tls.c (allocate_and_init): Return void.
	(_dl_update_slotinfo): Block signals, use atomic update.

nptl/ChangeLog:

2014-01-03  Andrew Hunter  <ahh@google.com>

	* nptl/Makefile (tst-tls7): New test.
	* nptl/tst-tls7.c: New file.
	* nptl/tst-tls7mod.c: New file.
	* nptl/allocatestack.c (init_one_static_tls): Use atomic barrier.
2014-01-03 11:22:26 -08:00

44 lines
1.4 KiB
C

/* Copyright (C) 2013 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
<http://www.gnu.org/licenses/>. */
/* Dynamic module with TLS to be accessed by a signal handler to check safety
of that mode. */
#include <semaphore.h>
#include <signal.h>
#include <unistd.h>
/* This is an unlikely value to see in incorrectly initialized TLS
block -- make sure we're initialized properly. */
static __thread intptr_t tls_data = 0xdeadbeef;
void
action (int signo, siginfo_t *info, void *ignored)
{
sem_t *sem = info->si_value.sival_ptr;
if (tls_data != 0xdeadbeef)
{
write (STDOUT_FILENO, "wrong TLS value\n", 17);
_exit (1);
}
/* arbitrary choice, just write something unique-ish. */
tls_data = (intptr_t) info;
sem_post (sem);
}