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authorUlrich Drepper <drepper@redhat.com>2004-03-19 00:14:42 +0000
committerUlrich Drepper <drepper@redhat.com>2004-03-19 00:14:42 +0000
commit439ff07be06e9354151f984c7d0d2fb05917e8be (patch)
tree2c3471a5c7e73d1f6a043b082266e7248b992c02 /nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c
parent701a7b234eab5615adb472b5dc5b0a9199d69f9b (diff)
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Update.
2004-03-18  Ulrich Drepper  <drepper@redhat.com>

	* posix/sched.h: Change sched_getaffinity and sched_setaffinity
	interfaces: add new second parameter.
	* sysdeps/generic/sched_getaffinity.c: Implement interface change.
	* sysdeps/generic/sched_setaffinity.c: Likewise.
	* sysdeps/unix/sysv/linux/sched_getaffinity.c: Likewise.  Add
	compatibility interface.
	* sysdeps/unix/sysv/linux/sched_setaffinity.c: Likewise.
	* sysdeps/unix/sysv/linux/Versions: Add versions for changed
	interfaces.
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c')
-rw-r--r--nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c76
1 files changed, 69 insertions, 7 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c b/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c
index 7680068155..9a73d2c3cb 100644
--- a/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c
+++ b/nptl/sysdeps/unix/sysv/linux/pthread_setaffinity.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2003 Free Software Foundation, Inc.
+/* 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.
 
@@ -17,22 +17,84 @@
    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>
+#include <shlib-compat.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
-pthread_setaffinity_np (th, cpuset)
-     pthread_t th;
-     const cpu_set_t *cpuset;
+__determine_cpumask_size (pid_t tid)
 {
-  struct pthread *pd = (struct pthread *) th;
   INTERNAL_SYSCALL_DECL (err);
-  int res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid,
-			      sizeof (cpu_set_t), cpuset);
+  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.  */
+  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;
+
+  INTERNAL_SYSCALL_DECL (err);
+  res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, cpusetsize,
+			  cpuset);
   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, 2_3_3, 2_3_4)
+int
+__pthread_setaffinity_old (const pthread_attr_t *attr, cpu_set_t *cpuset)
+{
+  /* The old interface by default assumed a 1024 processor bitmap.  */
+  return __pthread_setaffinity_new (attr, 128, cpuset);
+}
+compat_symbol (libpthread, __pthread_setaffinity_old, pthread_setaffinity_np,
+	       GLIBC_2_3_3);
+#endif