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-rw-r--r--libpthread/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c b/libpthread/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c
new file mode 100644
index 000000000..fa7b48904
--- /dev/null
+++ b/libpthread/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c
@@ -0,0 +1,86 @@
+/* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
+
+ 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 <alloca.h>
+#include <errno.h>
+#include <pthreadP.h>
+#include <sysdep.h>
+#include <sys/types.h>
+
+
+size_t __kernel_cpumask_size;
+
+
+/* Determine the current affinity. As a side affect we learn
+ about the size of the cpumask_t in the kernel. */
+int
+__determine_cpumask_size (pid_t tid)
+{
+ INTERNAL_SYSCALL_DECL (err);
+ int res;
+
+ size_t psize = 128;
+ void *p = alloca (psize);
+
+ while (res = INTERNAL_SYSCALL (sched_getaffinity, err, 3, tid, psize, p),
+ INTERNAL_SYSCALL_ERROR_P (res, err)
+ && INTERNAL_SYSCALL_ERRNO (res, err) == EINVAL)
+ p = extend_alloca (p, psize, 2 * psize);
+
+ if (res == 0 || INTERNAL_SYSCALL_ERROR_P (res, err))
+ return INTERNAL_SYSCALL_ERRNO (res, err);
+
+ __kernel_cpumask_size = res;
+
+ return 0;
+}
+
+
+int
+__pthread_setaffinity_new (pthread_t th, size_t cpusetsize,
+ const cpu_set_t *cpuset)
+{
+ const struct pthread *pd = (const struct pthread *) th;
+
+ INTERNAL_SYSCALL_DECL (err);
+ int res;
+
+ if (__builtin_expect (__kernel_cpumask_size == 0, 0))
+ {
+ res = __determine_cpumask_size (pd->tid);
+ if (res != 0)
+ return res;
+ }
+
+ /* We now know the size of the kernel cpumask_t. Make sure the user
+ does not request to set a bit beyond that. */
+ size_t cnt;
+ for (cnt = __kernel_cpumask_size; cnt < cpusetsize; ++cnt)
+ if (((char *) cpuset)[cnt] != '\0')
+ /* Found a nonzero byte. This means the user request cannot be
+ fulfilled. */
+ return EINVAL;
+
+ res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, cpusetsize,
+ cpuset);
+ return (INTERNAL_SYSCALL_ERROR_P (res, err)
+ ? INTERNAL_SYSCALL_ERRNO (res, err)
+ : 0);
+}
+weak_alias(__pthread_setaffinity_new, pthread_setaffinity_np)