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/* Copyright (C) 2002, 2003, 2004, 2006, 2007, 2008
Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
OpenSolaris bits contributed by David Bartley
<dtbartle@csclub.uwaterloo.ca>, 2008.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <tls.h>
#include <ucontext.h>
#include <sys/stack.h>
#include <sys/stack.h>
#include <sys/regset.h>
#include <sys/lwp.h>
#include <inline-syscall.h>
#include <schedP.h>
#include <createthread_arch.c>
DECLARE_INLINE_SYSCALL (int, lwp_create, ucontext_t *ucp, int flags,
pthread_t *new_lwp);
DECLARE_INLINE_SYSCALL (int, lwp_continue, pthread_t lwpid);
DECLARE_INLINE_SYSCALL (int, lwp_kill, pthread_t lwpid, int sig);
#ifndef TLS_MULTIPLE_THREADS_IN_TCB
/* Pointer to the corresponding variable in libc. */
int *__libc_multiple_threads_ptr attribute_hidden;
#endif
static int
create_thread (struct pthread *pd, const struct pthread_attr *attr,
STACK_VARIABLES_PARMS)
{
#ifdef TLS_TCB_AT_TP
assert (pd->header.tcb != NULL);
#endif
/* Do arch-specific creation. */
ucontext_t ctx = {0};
int errval = create_thread_arch (&ctx, pd, attr, STACK_VARIABLES_ARGS);
if (errval != 0)
return errval;
/* Threads inherit the parent's sigmask. */
pthread_sigmask (SIG_SETMASK, NULL, &ctx.uc_sigmask);
/* One more thread. We cannot have the thread do this itself, since it
might exist but not have been scheduled yet by the time we've returned
and need to check the value to behave correctly. We must do it before
creating the thread, in case it does get scheduled first and then
might mistakenly think it was the only thread. In the failure case,
we momentarily store a false value; this doesn't matter because there
is no kosher thing a signal handler interrupting us right here can do
that cares whether the thread count is correct. */
atomic_increment (&__nptl_nthreads);
/* We set the thread to be initially suspended so that we can set
scheduling magic. */
int lwp_flags =
((attr->flags & ATTR_FLAG_DAEMON) ? LWP_DAEMON : 0) |
((attr->flags & ATTR_FLAG_DETACHSTATE) ? LWP_DETACHED : 0);
if ((attr->flags & ATTR_FLAG_THR_CREATE) == 0)
lwp_flags |= LWP_SUSPENDED;
errval = INLINE_SYSCALL (lwp_create, 3, &ctx, lwp_flags, &pd->tid);
if (errval == 0 && (attr->flags & ATTR_FLAG_THR_CREATE) == 0)
{
/* Set scheduling. */
if (attr->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET))
{
int policy, priority;
errval = __sched_getscheduler_id (P_LWPID, pd->tid,
&policy, &priority);
if (errval == 0)
{
if (attr->flags & ATTR_FLAG_SCHED_SET)
priority = attr->schedparam.__sched_priority;
if (attr->flags & ATTR_FLAG_POLICY_SET)
policy = attr->schedpolicy;
errval = __sched_setscheduler_id (P_LWPID, pd->tid,
policy, priority);
}
if (errval != 0)
errval = EPERM;
}
/* TODO: remove this hack once scheduling works. */
errval = 0;
if (errval == 0 && !(attr->flags & ATTR_FLAG_SUSPENDED))
{
errval = INLINE_SYSCALL (lwp_continue, 1, pd->tid);
}
else if (errval != 0)
{
pd->flags |= ATTR_FLAG_CREATE_FAILED;
INLINE_SYSCALL (lwp_continue, 1, pd->tid);
if (!IS_DETACHED (pd))
{
int result;
lll_wait_tid (pd->tid);
}
/* Note: if the thread is detached, start_thread will free pd;
otherwise the caller of create_thread will free pd. */
}
}
if (errval == 0)
{
/* We now have for sure more than one thread. The main thread might
not yet have the flag set. No need to set the global variable
again if this is what we use. */
THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1);
}
else
{
atomic_decrement (&__nptl_nthreads); /* Oops, we lied for a second. */
}
return errval;
}
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