[src/trunk]: src/sys Re-add yield(). Only used by compat code at the moment.

[gmcgarry <gmcgarry%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/ea33fd2eb2b3
branches:  trunk
changeset: 540693:ea33fd2eb2b3
user:      gmcgarry <gmcgarry%NetBSD.org@localhost>
date:      Sat Dec 21 23:52:05 2002 +0000

description:
Re-add yield().  Only used by compat code at the moment.

diffstat:

 sys/kern/kern_synch.c |  25 +++++++++++++++++++++++--
 sys/sys/proc.h        |   3 ++-
 2 files changed, 25 insertions(+), 3 deletions(-)

diffs (63 lines):

diff -r 05bd2aa6c8aa -r ea33fd2eb2b3 sys/kern/kern_synch.c
--- a/sys/kern/kern_synch.c     Sat Dec 21 23:50:47 2002 +0000
+++ b/sys/kern/kern_synch.c     Sat Dec 21 23:52:05 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_synch.c,v 1.116 2002/12/20 05:43:09 gmcgarry Exp $        */
+/*     $NetBSD: kern_synch.c,v 1.117 2002/12/21 23:52:06 gmcgarry Exp $        */
 
 /*-
  * Copyright (c) 1999, 2000 The NetBSD Foundation, Inc.
@@ -78,7 +78,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_synch.c,v 1.116 2002/12/20 05:43:09 gmcgarry Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_synch.c,v 1.117 2002/12/21 23:52:06 gmcgarry Exp $");
 
 #include "opt_ddb.h"
 #include "opt_ktrace.h"
@@ -718,6 +718,27 @@
 }
 
 /*
+ * General yield call.  Puts the current process back on its run queue and
+ * performs a voluntary context switch.  Should only be called when the
+ * current process explicitly requests it (eg sched_yield(2) in compat code).
+ */
+void
+yield(void)
+{
+       struct proc *p = curproc;
+       int s;
+
+       SCHED_LOCK(s);
+       p->p_priority = p->p_usrpri;
+       p->p_stat = SRUN;
+       setrunqueue(p);
+       p->p_stats->p_ru.ru_nvcsw++;
+       mi_switch(p, NULL);
+       SCHED_ASSERT_UNLOCKED();
+       splx(s);
+}
+
+/*
  * General preemption call.  Puts the current process back on its run queue
  * and performs an involuntary context switch.  If a process is supplied,
  * we switch to that process.  Otherwise, we use the normal process selection
diff -r 05bd2aa6c8aa -r ea33fd2eb2b3 sys/sys/proc.h
--- a/sys/sys/proc.h    Sat Dec 21 23:50:47 2002 +0000
+++ b/sys/sys/proc.h    Sat Dec 21 23:52:05 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: proc.h,v 1.151 2002/12/21 16:22:10 manu Exp $  */
+/*     $NetBSD: proc.h,v 1.152 2002/12/21 23:52:05 gmcgarry Exp $      */
 
 /*-
  * Copyright (c) 1986, 1989, 1991, 1993
@@ -437,6 +437,7 @@
 void   fixjobc(struct proc *p, struct pgrp *pgrp, int entering);
 int    inferior(struct proc *p, struct proc *q);
 int    leavepgrp(struct proc *p);
+void   yield(void);
 void   preempt(struct proc *);
 void   mi_switch(struct proc *, struct proc *);
 struct proc *chooseproc(void);