Add pthread_yield function

* pthread/pt-yield.c: New file.
* Makefile (SRCS): Add pt-yield.c
* Makefile.am (libpthread_a_SOURCES): Add pt-yield.c

4 files changed, 37 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 04dfb26..2b895e8 100644
--- a/Makefile
+++ b/Makefile
@@ -122,6 +122,7 @@ SRCS := pt-attr.c pt-attr-destroy.c pt-attr-getdetachstate.c		    \
 	pt-getcpuclockid.c						    \
 									    \
 	pt-getschedparam.c pt-setschedparam.c pt-setschedprio.c		    \
+	pt-yield.c							    \
 									    \
 	sem-close.c sem-destroy.c sem-getvalue.c sem-init.c sem-open.c	    \
 	sem-post.c sem-timedwait.c sem-trywait.c sem-unlink.c		    \
diff --git a/Makefile.am b/Makefile.am
index e59c946..e1c062c 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -133,6 +133,7 @@ libpthread_a_SOURCES = pt-attr.c pt-attr-destroy.c pt-attr-getdetachstate.c \
 	pt-kill.c							    \
 	pt-getcpuclockid.c						    \
 	pt-getschedparam.c pt-setschedparam.c pt-setschedprio.c		    \
+	pt-yield.c							    \
 	sem-close.c sem-init.c sem-timedwait.c sem-wait.c		    \
 	sem-destroy.c sem-open.c sem-trywait.c sem-getvalue.c		    \
 	sem-post.c sem-unlink.c						    \
diff --git a/include/pthread/pthread.h b/include/pthread/pthread.h
index fbe3294..e6b9249 100644
--- a/include/pthread/pthread.h
+++ b/include/pthread/pthread.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2000, 2002, 2005, 2006, 2007, 2008, 2009
+/* Copyright (C) 2000, 2002, 2005, 2006, 2007, 2008, 2009, 2010
      Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -734,6 +734,14 @@ extern int pthread_setschedparam (pthread_t thread, int policy,
 
 /* Set thread THREAD's scheduling priority.  */
 extern int pthread_setschedprio (pthread_t thread, int prio);
+
+#ifdef __USE_GNU
+/* Yield the processor to another thread or process.
+   This function is similar to the POSIX `sched_yield' function but
+   might be differently implemented in the case of a m-on-n thread
+   implementation.  */
+extern int pthread_yield (void);
+#endif
 
 
 /* Kernel-specific interfaces.  */
diff --git a/pthread/pt-yield.c b/pthread/pt-yield.c
new file mode 100644
index 0000000..27848bb
--- /dev/null
+++ b/pthread/pt-yield.c
@@ -0,0 +1,26 @@
+/* Yield the processor to another thread or process.
+   Copyright (C) 2010 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 Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <pthread.h>
+#include <sched.h>
+
+int pthread_yield(void)
+{
+  return sched_yield ();
+}