glibc/nptl/pthread_setattr_default_np.c

112 lines
3.2 KiB
C

/* Set the default attributes to be used by pthread_create in the process.
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/>. */
#include <errno.h>
#include <stdlib.h>
#include <pthreadP.h>
#include <assert.h>
#include <string.h>
int
pthread_setattr_default_np (const pthread_attr_t *in)
{
const struct pthread_attr *real_in;
struct pthread_attr attrs;
int ret;
assert (sizeof (*in) >= sizeof (struct pthread_attr));
real_in = (struct pthread_attr *) in;
/* Catch invalid values. */
int policy = real_in->schedpolicy;
ret = check_sched_policy_attr (policy);
if (ret)
return ret;
const struct sched_param *param = &real_in->schedparam;
if (param->sched_priority > 0)
{
ret = check_sched_priority_attr (param->sched_priority, policy);
if (ret)
return ret;
}
ret = check_cpuset_attr (real_in->cpuset, real_in->cpusetsize);
if (ret)
return ret;
/* stacksize == 0 is fine. It means that we don't change the current
value. */
if (real_in->stacksize != 0)
{
ret = check_stacksize_attr (real_in->stacksize);
if (ret)
return ret;
}
/* Having a default stack address is wrong. */
if (real_in->flags & ATTR_FLAG_STACKADDR)
return EINVAL;
attrs = *real_in;
/* Now take the lock because we start writing into
__default_pthread_attr. */
lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
/* Free the cpuset if the input is 0. Otherwise copy in the cpuset
contents. */
size_t cpusetsize = attrs.cpusetsize;
if (cpusetsize == 0)
{
free (__default_pthread_attr.cpuset);
__default_pthread_attr.cpuset = NULL;
}
else if (cpusetsize == __default_pthread_attr.cpusetsize)
{
attrs.cpuset = __default_pthread_attr.cpuset;
memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);
}
else
{
/* This may look wrong at first sight, but it isn't. We're freeing
__default_pthread_attr.cpuset and allocating to attrs.cpuset because
we'll copy over all of attr to __default_pthread_attr later. */
cpu_set_t *newp = realloc (__default_pthread_attr.cpuset,
cpusetsize);
if (newp == NULL)
{
ret = ENOMEM;
goto out;
}
attrs.cpuset = newp;
memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);
}
/* We don't want to accidentally set the default stacksize to zero. */
if (attrs.stacksize == 0)
attrs.stacksize = __default_pthread_attr.stacksize;
__default_pthread_attr = attrs;
out:
lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
return ret;
}