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Diffstat (limited to 'sysdeps/unix/sysv/linux/pthread_setaffinity.c')
-rw-r--r--sysdeps/unix/sysv/linux/pthread_setaffinity.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/pthread_setaffinity.c b/sysdeps/unix/sysv/linux/pthread_setaffinity.c
new file mode 100644
index 0000000000..874cf4b578
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/pthread_setaffinity.c
@@ -0,0 +1,104 @@
+/* Copyright (C) 2003-2014 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <alloca.h>
+#include <errno.h>
+#include <pthreadP.h>
+#include <sysdep.h>
+#include <sys/types.h>
+#include <shlib-compat.h>
+
+
+size_t __kernel_cpumask_size attribute_hidden;
+
+
+/* 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 (__glibc_unlikely (__kernel_cpumask_size == 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.  */
+  for (size_t 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);
+
+#ifdef RESET_VGETCPU_CACHE
+  if (!INTERNAL_SYSCALL_ERROR_P (res, err))
+    RESET_VGETCPU_CACHE ();
+#endif
+
+  return (INTERNAL_SYSCALL_ERROR_P (res, err)
+	  ? INTERNAL_SYSCALL_ERRNO (res, err)
+	  : 0);
+}
+versioned_symbol (libpthread, __pthread_setaffinity_new,
+		  pthread_setaffinity_np, GLIBC_2_3_4);
+
+
+#if SHLIB_COMPAT (libpthread, GLIBC_2_3_3, GLIBC_2_3_4)
+int
+__pthread_setaffinity_old (pthread_t th, cpu_set_t *cpuset)
+{
+  /* The old interface by default assumed a 1024 processor bitmap.  */
+  return __pthread_setaffinity_new (th, 128, cpuset);
+}
+compat_symbol (libpthread, __pthread_setaffinity_old, pthread_setaffinity_np,
+	       GLIBC_2_3_3);
+#endif