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authorUlrich Drepper <drepper@redhat.com>2007-04-03 23:29:18 +0000
committerUlrich Drepper <drepper@redhat.com>2007-04-03 23:29:18 +0000
commiteab1bdfb8ef2902e7b68352d6ce1b5d603597e36 (patch)
tree00ac9dba5b0687fd0bb056bed3d75e812a2c6a79 /posix/sched_cpucount.c
parent9700b0390e40c7ffaed2a74ae3285edfe6080bd3 (diff)
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* posix/Makefile (routines): Add sched_cpucount.
	(tests): Add tst-cpucount.
	* posix/sched_cpucount.c: New file.
	* posix/tst-cpucount.c: New file.
	* posix/Versions: Export __sched_cpucount with version GLIBC_2.6.
Diffstat (limited to 'posix/sched_cpucount.c')
-rw-r--r--posix/sched_cpucount.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/posix/sched_cpucount.c b/posix/sched_cpucount.c
new file mode 100644
index 0000000000..8404e8f3c0
--- /dev/null
+++ b/posix/sched_cpucount.c
@@ -0,0 +1,52 @@
+/* Copyright (C) 2007 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <limits.h>
+#include <sched.h>
+
+
+int
+__sched_cpucount (cpu_set_t *setp)
+{
+  int s = 0;
+  for (unsigned int j = 0; j < __CPU_SETSIZE / __NCPUBITS; ++j)
+    {
+      __cpu_mask l = setp->__bits[j];
+      if (l == 0)
+	continue;
+
+#if LONG_BIT > 32
+      l = (l & 0x5555555555555555ul) + ((l >> 1) & 0x5555555555555555ul);
+      l = (l & 0x3333333333333333ul) + ((l >> 2) & 0x3333333333333333ul);
+      l = (l & 0x0f0f0f0f0f0f0f0ful) + ((l >> 4) & 0x0f0f0f0f0f0f0f0ful);
+      l = (l & 0x00ff00ff00ff00fful) + ((l >> 8) & 0x00ff00ff00ff00fful);
+      l = (l & 0x0000ffff0000fffful) + ((l >> 16) & 0x0000ffff0000fffful);
+      l = (l & 0x00000000fffffffful) + ((l >> 32) & 0x00000000fffffffful);
+#else
+      l = (l & 0x55555555ul) + ((l >> 1) & 0x55555555ul);
+      l = (l & 0x33333333ul) + ((l >> 2) & 0x33333333ul);
+      l = (l & 0x0f0f0f0ful) + ((l >> 4) & 0x0f0f0f0ful);
+      l = (l & 0x00ff00fful) + ((l >> 8) & 0x00ff00fful);
+      l = (l & 0x0000fffful) + ((l >> 16) & 0x0000fffful);
+#endif
+
+      s += l;
+    }
+
+  return s;
+}