Impl. linux syscalls sched_getaffinity/sched_setaffinity but

protect its use by #ifdef INTERNAL_SYSCALL since not all
arch's has INTERNAL_SYSCALL.

All arch's not having INTERNAL_SYSCALL in 
libc/sysdeps/linux/<arch>/bits/syscalls.h should get an update
from glibc.

1 files changed, 78 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/common/sched_setaffinity.c b/libc/sysdeps/linux/common/sched_setaffinity.c
new file mode 100644
index 000000000..a25fbe356
--- /dev/null
+++ b/libc/sysdeps/linux/common/sched_setaffinity.c
@@ -0,0 +1,78 @@
+/* Copyright (C) 2002, 2003, 2004, 2005, 2006 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 <features.h>
+#ifdef __USE_GNU
+
+#include <sched.h>
+#include <sys/types.h>
+#include <sys/syscall.h>
+
+#ifdef INTERNAL_SYSCALL /* remove this when all archs has this #defined */
+
+#include <string.h>
+#include <unistd.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <alloca.h>
+
+libc_hidden_proto(getpid)
+
+#define __NR___syscall_sched_setaffinity __NR_sched_setaffinity
+static inline _syscall3(int, __syscall_sched_setaffinity, __kernel_pid_t, pid,
+			size_t, cpusetsize, cpu_set_t *, cpuset);
+
+static size_t __kernel_cpumask_size;
+
+int sched_setaffinity(pid_t pid, size_t cpusetsize, const cpu_set_t *cpuset)
+{
+	size_t cnt;
+	if (unlikely (__kernel_cpumask_size == 0)) {
+		INTERNAL_SYSCALL_DECL (err);
+		int res;
+		size_t psize = 128;
+		void *p = alloca (psize);
+
+		while (res = INTERNAL_SYSCALL (sched_getaffinity, err, 3, getpid (),
+					       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)) {
+			__set_errno (INTERNAL_SYSCALL_ERRNO (res, err));
+			return -1;
+		}
+
+		__kernel_cpumask_size = 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 (cnt = __kernel_cpumask_size; cnt < cpusetsize; ++cnt)
+		if (((char *) cpuset)[cnt] != '\0') {
+			/* Found a nonzero byte.  This means the user request cannot be
+			   fulfilled.  */
+			__set_errno (EINVAL);
+			return -1;
+		}
+
+	return INLINE_SYSCALL (sched_setaffinity, 3, pid, cpusetsize, cpuset);
+}
+#endif
+#endif