"idle priority" support. Based on code from Henrik Vestergaard Draboel,

but substantially rewritten by me.

21 files changed, 634 insertions, 218 deletions

diff --git a/sys/amd64/amd64/cpu_switch.S b/sys/amd64/amd64/cpu_switch.S
index ad83a9a..ab40500 100644
--- a/sys/amd64/amd64/cpu_switch.S
+++ b/sys/amd64/amd64/cpu_switch.S
@@ -33,7 +33,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: swtch.s,v 1.13 1994/09/02 05:58:51 davidg Exp $
+ *	$Id: swtch.s,v 1.14 1994/10/01 02:56:03 davidg Exp $
  */
 
 #include "npx.h"	/* for NNPX */
@@ -59,10 +59,11 @@
  * queues.
  */
 	.data
-	.globl	_curpcb, _whichqs, _whichrtqs
+	.globl	_curpcb, _whichqs, _whichrtqs, _whichidqs
 _curpcb:	.long	0			/* pointer to curproc's PCB area */
 _whichqs:	.long	0			/* which run queues have data */
 _whichrtqs:	.long	0			/* which realtime run queues have data */
+_whichidqs:	.long	0			/* which idletime run queues have data */
 
 	.globl	_qs,_cnt,_panic
 	.comm	_noproc,4
@@ -84,10 +85,15 @@ ENTRY(setrunqueue)
 	pushl	$set2
 	call	_panic
 set1:
-	cmpl	$RTPRIO_RTOFF,P_RTPRIO(%eax)	/* Realtime process ? */
-	je	set1_nort
+	cmpw	$RTP_PRIO_NORMAL,P_RTPRIO_TYPE(%eax) /* normal priority process? */
+	je	set_nort
 
-	movl	P_RTPRIO(%eax),%edx
+	movzwl	P_RTPRIO_PRIO(%eax),%edx
+
+	cmpw	$RTP_PRIO_REALTIME,P_RTPRIO_TYPE(%eax) /* realtime priority? */
+	jne	set_id				/* must be idle priority */
+	
+set_rt:
 	btsl	%edx,_whichrtqs			/* set q full bit */
 	shll	$3,%edx
 	addl	$_rtqs,%edx			/* locate q hdr */
@@ -97,7 +103,19 @@ set1:
 	movl	%eax,P_BACK(%edx)
 	movl	%eax,P_FORW(%ecx)
 	ret
-set1_nort:                    
+
+set_id:	
+	btsl	%edx,_whichidqs			/* set q full bit */
+	shll	$3,%edx
+	addl	$_idqs,%edx			/* locate q hdr */
+	movl	%edx,P_FORW(%eax)		/* link process on tail of q */
+	movl	P_BACK(%edx),%ecx
+	movl	%ecx,P_BACK(%eax)
+	movl	%eax,P_BACK(%edx)
+	movl	%eax,P_FORW(%ecx)
+	ret
+
+set_nort:                    			/*  Normal (RTOFF) code */
 	movzbl	P_PRI(%eax),%edx
 	shrl	$2,%edx
 	btsl	%edx,_whichqs			/* set q full bit */
@@ -119,13 +137,17 @@ set2:	.asciz	"setrunqueue"
  */
 ENTRY(remrq)
 	movl	4(%esp),%eax
-	cmpl	$RTPRIO_RTOFF,P_RTPRIO(%eax)	/* Realtime process ? */
+	cmpw	$RTP_PRIO_NORMAL,P_RTPRIO_TYPE(%eax) /* normal priority process? */
 	je	rem_nort
 
-	movl	P_RTPRIO(%eax),%edx
+	movzwl	P_RTPRIO_PRIO(%eax),%edx
+
+	cmpw	$RTP_PRIO_REALTIME,P_RTPRIO_TYPE(%eax) /* normal priority process? */
+	jne	rem_id
+		
 	btrl	%edx,_whichrtqs			/* clear full bit, panic if clear already */
 	jb	rem1rt
-	pushl	$rem3
+	pushl	$rem3rt
 	call	_panic
 rem1rt:
 	pushl	%edx
@@ -146,6 +168,31 @@ rem1rt:
 rem2rt:
 	movl	$0,P_BACK(%eax)			/* zap reverse link to indicate off list */
 	ret
+rem_id:
+	btrl	%edx,_whichidqs			/* clear full bit, panic if clear already */
+	jb	rem1id
+	pushl	$rem3id
+	call	_panic
+rem1id:
+	pushl	%edx
+	movl	P_FORW(%eax),%ecx		/* unlink process */
+	movl	P_BACK(%eax),%edx
+	movl	%edx,P_BACK(%ecx)
+	movl	P_BACK(%eax),%ecx
+	movl	P_FORW(%eax),%edx
+	movl	%edx,P_FORW(%ecx)
+	popl	%edx
+	movl	$_idqs,%ecx
+	shll	$3,%edx
+	addl	%edx,%ecx
+	cmpl	P_FORW(%ecx),%ecx		/* q still has something? */
+	je	rem2id
+	shrl	$3,%edx				/* yes, set bit as still full */
+	btsl	%edx,_whichidqs
+rem2id:
+	movl	$0,P_BACK(%eax)			/* zap reverse link to indicate off list */
+	ret
+
 rem_nort:     
 	movzbl	P_PRI(%eax),%edx
 	shrl	$2,%edx
@@ -174,6 +221,8 @@ rem2:
 	ret
 
 rem3:	.asciz	"remrq"
+rem3rt:	.asciz	"remrq.rt"
+rem3id:	.asciz	"remrq.id"
 sw0:	.asciz	"cpu_switch"
 
 /*
@@ -200,10 +249,12 @@ _idle:
 	ALIGN_TEXT
 idle_loop:
 	cli
-	cmpl	$0,_whichrtqs
+	cmpl	$0,_whichrtqs			/* real-time queue */
 	jne	sw1a
-	cmpl	$0,_whichqs
+	cmpl	$0,_whichqs			/* normal queue */
 	jne	nortqr
+	cmpl	$0,_whichidqs			/* 'idle' queue */
+	jne	idqr
 #ifdef APM
 	call	_apm_cpu_idle
 	call	_apm_cpu_busy
@@ -269,7 +320,6 @@ sw1a:
 	testl	%edi,%edi
 	jz	nortqr				/* no realtime procs */
 
-rt2:
 	/* XXX - bsf is sloow */
 	bsfl	%edi,%ebx			/* find a full q */
 	jz	nortqr				/* no proc on rt q - try normal ... */
@@ -298,12 +348,13 @@ rt3:
 	jmp	swtch_com
 
 	/* old sw1a */
+/* Normal process priority's */
 nortqr:
 	movl	_whichqs,%edi
 2:
 	/* XXX - bsf is sloow */
 	bsfl	%edi,%ebx			/* find a full q */
-	jz	_idle				/* if none, idle */
+	jz	idqr				/* if none, idle */
 
 	/* XX update whichqs? */
 	btrl	%ebx,%edi			/* clear q full status */
@@ -326,6 +377,36 @@ nortqr:
 	btsl	%ebx,%edi			/* nope, set to indicate not empty */
 3:
 	movl	%edi,_whichqs			/* update q status */
+	jmp	swtch_com
+
+idqr: /* was sw1a */
+	movl    _whichidqs,%edi			/* pick next p. from idqs */
+
+	/* XXX - bsf is sloow */
+	bsfl	%edi,%ebx			/* find a full q */
+	jz	_idle				/* no proc, idle */
+
+	/* XX update whichqs? */
+	btrl	%ebx,%edi			/* clear q full status */
+	leal	_idqs(,%ebx,8),%eax		/* select q */
+	movl	%eax,%esi
+
+#ifdef        DIAGNOSTIC
+	cmpl	P_FORW(%eax),%eax		/* linked to self? (e.g. not on list) */
+	je	badsw				/* not possible */
+#endif
+
+	movl	P_FORW(%eax),%ecx		/* unlink from front of process q */
+	movl	P_FORW(%ecx),%edx
+	movl	%edx,P_FORW(%eax)
+	movl	P_BACK(%ecx),%eax
+	movl	%eax,P_BACK(%edx)
+
+	cmpl	P_FORW(%ecx),%esi		/* q empty */
+	je	id3
+	btsl	%ebx,%edi			/* nope, set to indicate not empty */
+id3:
+	movl	%edi,_whichidqs			/* update q status */
 
 swtch_com:
 	movl	$0,%eax
diff --git a/sys/amd64/amd64/genassym.c b/sys/amd64/amd64/genassym.c
index c568544..1ea7ba1 100644
--- a/sys/amd64/amd64/genassym.c
+++ b/sys/amd64/amd64/genassym.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)genassym.c	5.11 (Berkeley) 5/10/91
- *	$Id: genassym.c,v 1.11 1994/09/12 11:38:03 davidg Exp $
+ *	$Id: genassym.c,v 1.12 1994/10/02 01:28:38 rgrimes Exp $
  */
 
 #include <sys/param.h>
@@ -78,7 +78,8 @@ main()
 	printf("#define\tVM_PMAP %d\n", &vms->vm_pmap);
 	printf("#define\tP_ADDR %d\n", &p->p_addr);
 	printf("#define\tP_PRI %d\n", &p->p_priority);
-	printf("#define\tP_RTPRIO %d\n", &p->p_rtprio);
+	printf("#define\tP_RTPRIO_TYPE %d\n", &p->p_rtprio.type);
+	printf("#define\tP_RTPRIO_PRIO %d\n", &p->p_rtprio.prio);
 	printf("#define\tP_STAT %d\n", &p->p_stat);
 	printf("#define\tP_WCHAN %d\n", &p->p_wchan);
 	printf("#define\tP_FLAG %d\n", &p->p_flag);
diff --git a/sys/amd64/amd64/swtch.s b/sys/amd64/amd64/swtch.s
index ad83a9a..ab40500 100644
--- a/sys/amd64/amd64/swtch.s
+++ b/sys/amd64/amd64/swtch.s
@@ -33,7 +33,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: swtch.s,v 1.13 1994/09/02 05:58:51 davidg Exp $
+ *	$Id: swtch.s,v 1.14 1994/10/01 02:56:03 davidg Exp $
  */
 
 #include "npx.h"	/* for NNPX */
@@ -59,10 +59,11 @@
  * queues.
  */
 	.data
-	.globl	_curpcb, _whichqs, _whichrtqs
+	.globl	_curpcb, _whichqs, _whichrtqs, _whichidqs
 _curpcb:	.long	0			/* pointer to curproc's PCB area */
 _whichqs:	.long	0			/* which run queues have data */
 _whichrtqs:	.long	0			/* which realtime run queues have data */
+_whichidqs:	.long	0			/* which idletime run queues have data */
 
 	.globl	_qs,_cnt,_panic
 	.comm	_noproc,4
@@ -84,10 +85,15 @@ ENTRY(setrunqueue)
 	pushl	$set2
 	call	_panic
 set1:
-	cmpl	$RTPRIO_RTOFF,P_RTPRIO(%eax)	/* Realtime process ? */
-	je	set1_nort
+	cmpw	$RTP_PRIO_NORMAL,P_RTPRIO_TYPE(%eax) /* normal priority process? */
+	je	set_nort
 
-	movl	P_RTPRIO(%eax),%edx
+	movzwl	P_RTPRIO_PRIO(%eax),%edx
+
+	cmpw	$RTP_PRIO_REALTIME,P_RTPRIO_TYPE(%eax) /* realtime priority? */
+	jne	set_id				/* must be idle priority */
+	
+set_rt:
 	btsl	%edx,_whichrtqs			/* set q full bit */
 	shll	$3,%edx
 	addl	$_rtqs,%edx			/* locate q hdr */
@@ -97,7 +103,19 @@ set1:
 	movl	%eax,P_BACK(%edx)
 	movl	%eax,P_FORW(%ecx)
 	ret
-set1_nort:                    
+
+set_id:	
+	btsl	%edx,_whichidqs			/* set q full bit */
+	shll	$3,%edx
+	addl	$_idqs,%edx			/* locate q hdr */
+	movl	%edx,P_FORW(%eax)		/* link process on tail of q */
+	movl	P_BACK(%edx),%ecx
+	movl	%ecx,P_BACK(%eax)
+	movl	%eax,P_BACK(%edx)
+	movl	%eax,P_FORW(%ecx)
+	ret
+
+set_nort:                    			/*  Normal (RTOFF) code */
 	movzbl	P_PRI(%eax),%edx
 	shrl	$2,%edx
 	btsl	%edx,_whichqs			/* set q full bit */
@@ -119,13 +137,17 @@ set2:	.asciz	"setrunqueue"
  */
 ENTRY(remrq)
 	movl	4(%esp),%eax
-	cmpl	$RTPRIO_RTOFF,P_RTPRIO(%eax)	/* Realtime process ? */
+	cmpw	$RTP_PRIO_NORMAL,P_RTPRIO_TYPE(%eax) /* normal priority process? */
 	je	rem_nort
 
-	movl	P_RTPRIO(%eax),%edx
+	movzwl	P_RTPRIO_PRIO(%eax),%edx
+
+	cmpw	$RTP_PRIO_REALTIME,P_RTPRIO_TYPE(%eax) /* normal priority process? */
+	jne	rem_id
+		
 	btrl	%edx,_whichrtqs			/* clear full bit, panic if clear already */
 	jb	rem1rt
-	pushl	$rem3
+	pushl	$rem3rt
 	call	_panic
 rem1rt:
 	pushl	%edx
@@ -146,6 +168,31 @@ rem1rt:
 rem2rt:
 	movl	$0,P_BACK(%eax)			/* zap reverse link to indicate off list */
 	ret
+rem_id:
+	btrl	%edx,_whichidqs			/* clear full bit, panic if clear already */
+	jb	rem1id
+	pushl	$rem3id
+	call	_panic
+rem1id:
+	pushl	%edx
+	movl	P_FORW(%eax),%ecx		/* unlink process */
+	movl	P_BACK(%eax),%edx
+	movl	%edx,P_BACK(%ecx)
+	movl	P_BACK(%eax),%ecx
+	movl	P_FORW(%eax),%edx
+	movl	%edx,P_FORW(%ecx)
+	popl	%edx
+	movl	$_idqs,%ecx
+	shll	$3,%edx
+	addl	%edx,%ecx
+	cmpl	P_FORW(%ecx),%ecx		/* q still has something? */
+	je	rem2id
+	shrl	$3,%edx				/* yes, set bit as still full */
+	btsl	%edx,_whichidqs
+rem2id:
+	movl	$0,P_BACK(%eax)			/* zap reverse link to indicate off list */
+	ret
+
 rem_nort:     
 	movzbl	P_PRI(%eax),%edx
 	shrl	$2,%edx
@@ -174,6 +221,8 @@ rem2:
 	ret
 
 rem3:	.asciz	"remrq"
+rem3rt:	.asciz	"remrq.rt"
+rem3id:	.asciz	"remrq.id"
 sw0:	.asciz	"cpu_switch"
 
 /*
@@ -200,10 +249,12 @@ _idle:
 	ALIGN_TEXT
 idle_loop:
 	cli
-	cmpl	$0,_whichrtqs
+	cmpl	$0,_whichrtqs			/* real-time queue */
 	jne	sw1a
-	cmpl	$0,_whichqs
+	cmpl	$0,_whichqs			/* normal queue */
 	jne	nortqr
+	cmpl	$0,_whichidqs			/* 'idle' queue */
+	jne	idqr
 #ifdef APM
 	call	_apm_cpu_idle
 	call	_apm_cpu_busy
@@ -269,7 +320,6 @@ sw1a:
 	testl	%edi,%edi
 	jz	nortqr				/* no realtime procs */
 
-rt2:
 	/* XXX - bsf is sloow */
 	bsfl	%edi,%ebx			/* find a full q */
 	jz	nortqr				/* no proc on rt q - try normal ... */
@@ -298,12 +348,13 @@ rt3:
 	jmp	swtch_com
 
 	/* old sw1a */
+/* Normal process priority's */
 nortqr:
 	movl	_whichqs,%edi
 2:
 	/* XXX - bsf is sloow */
 	bsfl	%edi,%ebx			/* find a full q */
-	jz	_idle				/* if none, idle */
+	jz	idqr				/* if none, idle */
 
 	/* XX update whichqs? */
 	btrl	%ebx,%edi			/* clear q full status */
@@ -326,6 +377,36 @@ nortqr:
 	btsl	%ebx,%edi			/* nope, set to indicate not empty */
 3:
 	movl	%edi,_whichqs			/* update q status */
+	jmp	swtch_com
+
+idqr: /* was sw1a */
+	movl    _whichidqs,%edi			/* pick next p. from idqs */
+
+	/* XXX - bsf is sloow */
+	bsfl	%edi,%ebx			/* find a full q */
+	jz	_idle				/* no proc, idle */
+
+	/* XX update whichqs? */
+	btrl	%ebx,%edi			/* clear q full status */
+	leal	_idqs(,%ebx,8),%eax		/* select q */
+	movl	%eax,%esi
+
+#ifdef        DIAGNOSTIC
+	cmpl	P_FORW(%eax),%eax		/* linked to self? (e.g. not on list) */
+	je	badsw				/* not possible */
+#endif
+
+	movl	P_FORW(%eax),%ecx		/* unlink from front of process q */
+	movl	P_FORW(%ecx),%edx
+	movl	%edx,P_FORW(%eax)
+	movl	P_BACK(%ecx),%eax
+	movl	%eax,P_BACK(%edx)
+
+	cmpl	P_FORW(%ecx),%esi		/* q empty */
+	je	id3
+	btsl	%ebx,%edi			/* nope, set to indicate not empty */
+id3:
+	movl	%edi,_whichidqs			/* update q status */
 
 swtch_com:
 	movl	$0,%eax
diff --git a/sys/i386/i386/genassym.c b/sys/i386/i386/genassym.c
index c568544..1ea7ba1 100644
--- a/sys/i386/i386/genassym.c
+++ b/sys/i386/i386/genassym.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)genassym.c	5.11 (Berkeley) 5/10/91
- *	$Id: genassym.c,v 1.11 1994/09/12 11:38:03 davidg Exp $
+ *	$Id: genassym.c,v 1.12 1994/10/02 01:28:38 rgrimes Exp $
  */
 
 #include <sys/param.h>
@@ -78,7 +78,8 @@ main()
 	printf("#define\tVM_PMAP %d\n", &vms->vm_pmap);
 	printf("#define\tP_ADDR %d\n", &p->p_addr);
 	printf("#define\tP_PRI %d\n", &p->p_priority);
-	printf("#define\tP_RTPRIO %d\n", &p->p_rtprio);
+	printf("#define\tP_RTPRIO_TYPE %d\n", &p->p_rtprio.type);
+	printf("#define\tP_RTPRIO_PRIO %d\n", &p->p_rtprio.prio);
 	printf("#define\tP_STAT %d\n", &p->p_stat);
 	printf("#define\tP_WCHAN %d\n", &p->p_wchan);
 	printf("#define\tP_FLAG %d\n", &p->p_flag);
diff --git a/sys/i386/i386/swtch.s b/sys/i386/i386/swtch.s
index ad83a9a..ab40500 100644
--- a/sys/i386/i386/swtch.s
+++ b/sys/i386/i386/swtch.s
@@ -33,7 +33,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: swtch.s,v 1.13 1994/09/02 05:58:51 davidg Exp $
+ *	$Id: swtch.s,v 1.14 1994/10/01 02:56:03 davidg Exp $
  */
 
 #include "npx.h"	/* for NNPX */
@@ -59,10 +59,11 @@
  * queues.
  */
 	.data
-	.globl	_curpcb, _whichqs, _whichrtqs
+	.globl	_curpcb, _whichqs, _whichrtqs, _whichidqs
 _curpcb:	.long	0			/* pointer to curproc's PCB area */
 _whichqs:	.long	0			/* which run queues have data */
 _whichrtqs:	.long	0			/* which realtime run queues have data */
+_whichidqs:	.long	0			/* which idletime run queues have data */
 
 	.globl	_qs,_cnt,_panic
 	.comm	_noproc,4
@@ -84,10 +85,15 @@ ENTRY(setrunqueue)
 	pushl	$set2
 	call	_panic
 set1:
-	cmpl	$RTPRIO_RTOFF,P_RTPRIO(%eax)	/* Realtime process ? */
-	je	set1_nort
+	cmpw	$RTP_PRIO_NORMAL,P_RTPRIO_TYPE(%eax) /* normal priority process? */
+	je	set_nort
 
-	movl	P_RTPRIO(%eax),%edx
+	movzwl	P_RTPRIO_PRIO(%eax),%edx
+
+	cmpw	$RTP_PRIO_REALTIME,P_RTPRIO_TYPE(%eax) /* realtime priority? */
+	jne	set_id				/* must be idle priority */
+	
+set_rt:
 	btsl	%edx,_whichrtqs			/* set q full bit */
 	shll	$3,%edx
 	addl	$_rtqs,%edx			/* locate q hdr */
@@ -97,7 +103,19 @@ set1:
 	movl	%eax,P_BACK(%edx)
 	movl	%eax,P_FORW(%ecx)
 	ret
-set1_nort:                    
+
+set_id:	
+	btsl	%edx,_whichidqs			/* set q full bit */
+	shll	$3,%edx
+	addl	$_idqs,%edx			/* locate q hdr */
+	movl	%edx,P_FORW(%eax)		/* link process on tail of q */
+	movl	P_BACK(%edx),%ecx
+	movl	%ecx,P_BACK(%eax)
+	movl	%eax,P_BACK(%edx)
+	movl	%eax,P_FORW(%ecx)
+	ret
+
+set_nort:                    			/*  Normal (RTOFF) code */
 	movzbl	P_PRI(%eax),%edx
 	shrl	$2,%edx
 	btsl	%edx,_whichqs			/* set q full bit */
@@ -119,13 +137,17 @@ set2:	.asciz	"setrunqueue"
  */
 ENTRY(remrq)
 	movl	4(%esp),%eax
-	cmpl	$RTPRIO_RTOFF,P_RTPRIO(%eax)	/* Realtime process ? */
+	cmpw	$RTP_PRIO_NORMAL,P_RTPRIO_TYPE(%eax) /* normal priority process? */
 	je	rem_nort
 
-	movl	P_RTPRIO(%eax),%edx
+	movzwl	P_RTPRIO_PRIO(%eax),%edx
+
+	cmpw	$RTP_PRIO_REALTIME,P_RTPRIO_TYPE(%eax) /* normal priority process? */
+	jne	rem_id
+		
 	btrl	%edx,_whichrtqs			/* clear full bit, panic if clear already */
 	jb	rem1rt
-	pushl	$rem3
+	pushl	$rem3rt
 	call	_panic
 rem1rt:
 	pushl	%edx
@@ -146,6 +168,31 @@ rem1rt:
 rem2rt:
 	movl	$0,P_BACK(%eax)			/* zap reverse link to indicate off list */
 	ret
+rem_id:
+	btrl	%edx,_whichidqs			/* clear full bit, panic if clear already */
+	jb	rem1id
+	pushl	$rem3id
+	call	_panic
+rem1id:
+	pushl	%edx
+	movl	P_FORW(%eax),%ecx		/* unlink process */
+	movl	P_BACK(%eax),%edx
+	movl	%edx,P_BACK(%ecx)
+	movl	P_BACK(%eax),%ecx
+	movl	P_FORW(%eax),%edx
+	movl	%edx,P_FORW(%ecx)
+	popl	%edx
+	movl	$_idqs,%ecx
+	shll	$3,%edx
+	addl	%edx,%ecx
+	cmpl	P_FORW(%ecx),%ecx		/* q still has something? */
+	je	rem2id
+	shrl	$3,%edx				/* yes, set bit as still full */
+	btsl	%edx,_whichidqs
+rem2id:
+	movl	$0,P_BACK(%eax)			/* zap reverse link to indicate off list */
+	ret
+
 rem_nort:     
 	movzbl	P_PRI(%eax),%edx
 	shrl	$2,%edx
@@ -174,6 +221,8 @@ rem2:
 	ret
 
 rem3:	.asciz	"remrq"
+rem3rt:	.asciz	"remrq.rt"
+rem3id:	.asciz	"remrq.id"
 sw0:	.asciz	"cpu_switch"
 
 /*
@@ -200,10 +249,12 @@ _idle:
 	ALIGN_TEXT
 idle_loop:
 	cli
-	cmpl	$0,_whichrtqs
+	cmpl	$0,_whichrtqs			/* real-time queue */
 	jne	sw1a
-	cmpl	$0,_whichqs
+	cmpl	$0,_whichqs			/* normal queue */
 	jne	nortqr
+	cmpl	$0,_whichidqs			/* 'idle' queue */
+	jne	idqr
 #ifdef APM
 	call	_apm_cpu_idle
 	call	_apm_cpu_busy
@@ -269,7 +320,6 @@ sw1a:
 	testl	%edi,%edi
 	jz	nortqr				/* no realtime procs */
 
-rt2:
 	/* XXX - bsf is sloow */
 	bsfl	%edi,%ebx			/* find a full q */
 	jz	nortqr				/* no proc on rt q - try normal ... */
@@ -298,12 +348,13 @@ rt3:
 	jmp	swtch_com
 
 	/* old sw1a */
+/* Normal process priority's */
 nortqr:
 	movl	_whichqs,%edi
 2:
 	/* XXX - bsf is sloow */
 	bsfl	%edi,%ebx			/* find a full q */
-	jz	_idle				/* if none, idle */
+	jz	idqr				/* if none, idle */
 
 	/* XX update whichqs? */
 	btrl	%ebx,%edi			/* clear q full status */
@@ -326,6 +377,36 @@ nortqr:
 	btsl	%ebx,%edi			/* nope, set to indicate not empty */
 3:
 	movl	%edi,_whichqs			/* update q status */
+	jmp	swtch_com
+
+idqr: /* was sw1a */
+	movl    _whichidqs,%edi			/* pick next p. from idqs */
+
+	/* XXX - bsf is sloow */
+	bsfl	%edi,%ebx			/* find a full q */
+	jz	_idle				/* no proc, idle */
+
+	/* XX update whichqs? */
+	btrl	%ebx,%edi			/* clear q full status */
+	leal	_idqs(,%ebx,8),%eax		/* select q */
+	movl	%eax,%esi
+
+#ifdef        DIAGNOSTIC
+	cmpl	P_FORW(%eax),%eax		/* linked to self? (e.g. not on list) */
+	je	badsw				/* not possible */
+#endif
+
+	movl	P_FORW(%eax),%ecx		/* unlink from front of process q */
+	movl	P_FORW(%ecx),%edx
+	movl	%edx,P_FORW(%eax)
+	movl	P_BACK(%ecx),%eax
+	movl	%eax,P_BACK(%edx)
+
+	cmpl	P_FORW(%ecx),%esi		/* q empty */
+	je	id3
+	btsl	%ebx,%edi			/* nope, set to indicate not empty */
+id3:
+	movl	%edi,_whichidqs			/* update q status */
 
 swtch_com:
 	movl	$0,%eax
diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index 41693b2..44129c1 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)init_main.c	8.9 (Berkeley) 1/21/94
- * $Id: init_main.c,v 1.10 1994/09/13 14:46:47 dfr Exp $
+ * $Id: init_main.c,v 1.11 1994/09/25 19:33:33 phk Exp $
  */
 
 #include <sys/param.h>
@@ -165,7 +165,8 @@ main(framep)
 	p->p_flag = P_INMEM | P_SYSTEM;
 	p->p_stat = SRUN;
 	p->p_nice = NZERO;
-	p->p_rtprio = RTPRIO_RTOFF;
+	p->p_rtprio.type = RTP_PRIO_NORMAL;
+	p->p_rtprio.prio = 0;
 
 	bcopy("swapper", p->p_comm, sizeof ("swapper"));
 
diff --git a/sys/kern/init_sysent.c b/sys/kern/init_sysent.c
index 8ac5eae..15a3fb9 100644
--- a/sys/kern/init_sysent.c
+++ b/sys/kern/init_sysent.c
@@ -2,7 +2,7 @@
  * System call switch table.
  *
  * DO NOT EDIT-- this file is automatically generated.
- * created from	$Id: syscalls.master,v 1.9 1994/09/18 20:39:50 wollman Exp $
+ * created from	$Id: syscalls.master,v 1.10 1994/09/28 22:44:47 wollman Exp $
  */
 
 #include <sys/param.h>
@@ -446,7 +446,7 @@ struct sysent sysent[] = {
 	{ 2, setdomainname },			/* 163 = setdomainname */
 	{ 1, uname },			/* 164 = uname */
 	{ 2, sysarch },			/* 165 = sysarch */
-	{ 2, rtprio },			/* 166 = rtprio */
+	{ 3, rtprio },			/* 166 = rtprio */
 	{ 0, nosys },			/* 167 = nosys */
 	{ 0, nosys },			/* 168 = nosys */
 #ifdef SYSVSEM
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index 61e2f50..94c9e22 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_fork.c	8.6 (Berkeley) 4/8/94
- * $Id: kern_fork.c,v 1.5 1994/08/18 22:35:00 wollman Exp $
+ * $Id: kern_fork.c,v 1.6 1994/09/01 05:12:38 davidg Exp $
  */
 
 #include <sys/param.h>
@@ -269,11 +269,6 @@ again:
 	p2->p_estcpu = p1->p_estcpu;
 
 	/*
-	 * copy the realtime attibute
-	 */
-	p2->p_rtprio = p1->p_rtprio;
-
-	/*
 	 * This begins the section where we must prevent the parent
 	 * from being swapped.
 	 */
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 989cf1c..f9c3d7b 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_proc.c	8.4 (Berkeley) 1/4/94
- * $Id: kern_proc.c,v 1.5 1994/09/01 05:12:39 davidg Exp $
+ * $Id: kern_proc.c,v 1.6 1994/09/25 19:33:41 phk Exp $
  */
 
 #include <sys/param.h>
@@ -53,6 +53,7 @@
 
 struct prochd qs[NQS];		/* as good a place as any... */
 struct prochd rtqs[NQS];	/* Space for REALTIME queues too */
+struct prochd idqs[NQS];	/* Space for IDLE queues too */
 
 volatile struct proc *allproc;	/* all processes */
 struct proc *zombproc;		/* just zombies */
diff --git a/sys/kern/kern_resource.c b/sys/kern/kern_resource.c
index 704c501..6d2c274 100644
--- a/sys/kern/kern_resource.c
+++ b/sys/kern/kern_resource.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_resource.c	8.5 (Berkeley) 1/21/94
- * $Id: kern_resource.c,v 1.4 1994/09/01 05:12:40 davidg Exp $
+ * $Id: kern_resource.c,v 1.5 1994/09/25 19:33:42 phk Exp $
  */
 
 #include <sys/param.h>
@@ -195,8 +195,9 @@ donice(curp, chgp, n)
 
 /* rtprio system call */
 struct rtprio_args {
-        int     who;
-        pid_t   rtprio;
+	int		function;
+	pid_t		pid;
+	struct rtprio	*rtprio;
 };
 
 /*
@@ -211,45 +212,55 @@ rtprio(curp, uap, retval)
 	int *retval;
 {
 	register struct proc *p;
-	register int n = uap->rtprio;
 	register struct pcred *pcred = curp->p_cred;
+	struct rtprio rtp;
+	int error;
+
+	error = copyin(uap->rtprio, &rtp, sizeof(struct rtprio));
+	if (error)
+		return (error);
 
-	if (uap->who == 0)
+	if (uap->pid == 0)
 		p = curp;
 	else
-		p = pfind(uap->who);
+		p = pfind(uap->pid);
 
 	if (p == 0)
 		return (ESRCH);
 
-        if (n == RTPRIO_NOCHG) {
-                *retval = (int)p->p_rtprio;
-                return(0); }
-
-	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
-	    pcred->pc_ucred->cr_uid != p->p_ucred->cr_uid &&
-	    pcred->p_ruid != p->p_ucred->cr_uid)
-	      return (EPERM);
-
-         if (n == RTPRIO_RTOFF) {
-  	   if(suser(pcred->pc_ucred, &curp->p_acflag)&& !uap->who)
-	     return (EPERM); 
-           p->p_rtprio = RTPRIO_RTOFF;
-           *retval = RTPRIO_RTOFF;
-           return (0); }
-
-	if (n > RTPRIO_MAX)
-	   return (EINVAL);
-	if (n < RTPRIO_MIN)
-	   return (EINVAL);
-	if (suser(pcred->pc_ucred, &curp->p_acflag))
-		return (EPERM);
-
-	p->p_rtprio = n;
-
-        *retval = (int)p->p_rtprio;
-	return (0);
-};
+	switch (uap->function) {
+	case RTP_LOOKUP:
+		return (copyout(&p->p_rtprio, uap->rtprio, sizeof(struct rtprio)));
+	case RTP_SET:
+		if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
+		    pcred->pc_ucred->cr_uid != p->p_ucred->cr_uid &&
+		    pcred->p_ruid != p->p_ucred->cr_uid)
+		        return (EPERM);
+		/* disallow setting rtprio in most cases if not superuser */
+		if (suser(pcred->pc_ucred, &curp->p_acflag)) {
+			/* can't set someone else's */
+			if (uap->pid)
+				return (EPERM); 
+			/* can't set realtime priority */
+			if (rtp.type == RTP_PRIO_REALTIME)
+				return (EPERM);
+		}
+		switch (rtp.type) {
+		case RTP_PRIO_REALTIME:
+		case RTP_PRIO_NORMAL:
+		case RTP_PRIO_IDLE:
+			if (rtp.prio > RTP_PRIO_MAX)
+				return (EINVAL);
+			p->p_rtprio = rtp;
+			return (0);
+		default:
+			return (EINVAL);
+		}
+		
+	default:
+		return (EINVAL);
+	}
+}
 
 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
 struct setrlimit_args {
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c
index c74469f..a7d3774 100644
--- a/sys/kern/kern_synch.c
+++ b/sys/kern/kern_synch.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_synch.c	8.6 (Berkeley) 1/21/94
- * $Id: kern_synch.c,v 1.4 1994/09/01 05:12:41 davidg Exp $
+ * $Id: kern_synch.c,v 1.5 1994/09/25 19:33:44 phk Exp $
  */
 
 #include <sys/param.h>
@@ -609,6 +609,7 @@ rqinit()
 	for (i = 0; i < NQS; i++) {
 		qs[i].ph_link = qs[i].ph_rlink = (struct proc *)&qs[i];
 		rtqs[i].ph_link = rtqs[i].ph_rlink = (struct proc *)&rtqs[i];
+		idqs[i].ph_link = idqs[i].ph_rlink = (struct proc *)&idqs[i];
 	}
 }
 
@@ -662,7 +663,7 @@ resetpriority(p)
 {
 	register unsigned int newpriority;
 
-	if (p->p_rtprio == RTPRIO_RTOFF) {
+	if (p->p_rtprio.type == RTP_PRIO_NORMAL) {
 		newpriority = PUSER + p->p_estcpu / 4 + 2 * p->p_nice;
 		newpriority = min(newpriority, MAXPRI);
 		p->p_usrpri = newpriority;
diff --git a/sys/kern/syscalls.c b/sys/kern/syscalls.c
index 56eecbc..eb9491c 100644
--- a/sys/kern/syscalls.c
+++ b/sys/kern/syscalls.c
@@ -2,7 +2,7 @@
  * System call names.
  *
  * DO NOT EDIT-- this file is automatically generated.
- * created from	$Id: syscalls.master,v 1.9 1994/09/18 20:39:50 wollman Exp $
+ * created from	$Id: syscalls.master,v 1.10 1994/09/28 22:44:47 wollman Exp $
  */
 
 char *syscallnames[] = {
diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index d9a471e..0e7c986 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -1,4 +1,4 @@
-	$Id: syscalls.master,v 1.9 1994/09/18 20:39:50 wollman Exp $
+	$Id: syscalls.master,v 1.10 1994/09/28 22:44:47 wollman Exp $
 ;	from: @(#)syscalls.master	8.2 (Berkeley) 1/13/94
 ;
 ; System call name/number master file.
@@ -219,7 +219,7 @@
 163	STD	2 BSD	setdomainname
 164	STD	1 BSD	uname
 165	STD	2 BSD	sysarch
-166	STD	2 BSD	rtprio
+166	STD	3 BSD	rtprio
 167	UNIMPL	0 NOHIDE nosys
 168	UNIMPL	0 NOHIDE nosys
 #ifdef SYSVSEM
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 6155408..541ef95 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)proc.h	8.8 (Berkeley) 1/21/94
- * $Id: proc.h,v 1.7 1994/08/28 16:53:35 bde Exp $
+ * $Id: proc.h,v 1.8 1994/09/01 05:12:52 davidg Exp $
  */
 
 #ifndef _SYS_PROC_H_
@@ -156,6 +156,7 @@ struct	proc {
 
 	struct 	sysentvec *p_sysent; /* System call dispatch information. */
 
+	struct	rtprio p_rtprio; /* realtime priority */
 /* End area that is copied on creation. */
 #define	p_endcopy	p_thread
 	int	p_thread;	/* Id for this "thread"; Mach glue. XXX */
@@ -165,7 +166,6 @@ struct	proc {
 	u_short	p_xstat;	/* Exit status for wait; also stop signal. */
 	u_short	p_acflag;	/* Accounting flags. */
 	struct	rusage *p_ru;	/* Exit information. XXX */
-	u_long	p_rtprio;	/* realtime priority */
 };
 
 #define	p_session	p_pgrp->pg_session
@@ -248,6 +248,7 @@ extern struct proc *initproc, *pageproc; /* Process slots for init, pager. */
 #define	NQS	32			/* 32 run queues. */
 extern struct prochd qs[];
 extern struct prochd rtqs[];
+extern struct prochd idqs[];
 extern int	whichqs;	/* Bit mask summary of non-empty Q's. */
 struct	prochd {
 	struct	proc *ph_link;		/* Linked list of running processes. */
diff --git a/sys/sys/rtprio.h b/sys/sys/rtprio.h
index 7638f9b..9a22a34 100644
--- a/sys/sys/rtprio.h
+++ b/sys/sys/rtprio.h
@@ -28,7 +28,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id$
+ *	$Id: rtprio.h,v 1.1 1994/09/01 05:12:53 davidg Exp $
  */
 
 #ifndef _SYS_RTPRIO_H_
@@ -37,16 +37,34 @@
 /*
  * Process realtime-priority specifications to rtprio.
  */
-#define RTPRIO_MIN      0    /* relativ-FASTEST */
-#define RTPRIO_MAX      31   /* relativ-SLOWEST */
-#define RTPRIO_NOCHG    100  /* look only */
-#define RTPRIO_RTOFF    101  /* NON-realtime */
+
+/* priority types */
+#define RTP_PRIO_REALTIME	0
+#define RTP_PRIO_NORMAL		1
+#define RTP_PRIO_IDLE		2
+
+/* priority range */
+#define RTP_PRIO_MIN		0	/* Highest priority */
+#define RTP_PRIO_MAX		31	/* Lowest priority */
+
+/*
+ * rtprio() syscall functions
+ */
+#define RTP_LOOKUP		0
+#define RTP_SET			1
+
+#ifndef LOCORE
+struct rtprio {
+	u_short type;
+	u_short prio;
+};
+#endif
 
 #ifndef KERNEL
 #include <sys/cdefs.h>
 
 __BEGIN_DECLS
-int	rtprio __P((int, int));
+int	rtprio __P((int, pid_t, struct rtprio *));
 __END_DECLS
 #endif	/* !KERNEL */
 #endif	/* !_SYS_RTPRIO_H_ */
diff --git a/sys/sys/syscall-hide.h b/sys/sys/syscall-hide.h
index e09c893..b326435 100644
--- a/sys/sys/syscall-hide.h
+++ b/sys/sys/syscall-hide.h
@@ -2,7 +2,7 @@
  * System call hiders.
  *
  * DO NOT EDIT-- this file is automatically generated.
- * created from	$Id: syscalls.master,v 1.9 1994/09/18 20:39:50 wollman Exp $
+ * created from	$Id: syscalls.master,v 1.10 1994/09/28 22:44:47 wollman Exp $
  */
 
 HIDE_POSIX(fork)
diff --git a/sys/sys/syscall.h b/sys/sys/syscall.h
index 5d53601..c57bb7e 100644
--- a/sys/sys/syscall.h
+++ b/sys/sys/syscall.h
@@ -2,7 +2,7 @@
  * System call numbers.
  *
  * DO NOT EDIT-- this file is automatically generated.
- * created from	$Id: syscalls.master,v 1.9 1994/09/18 20:39:50 wollman Exp $
+ * created from	$Id: syscalls.master,v 1.10 1994/09/28 22:44:47 wollman Exp $
  */
 
 #define	SYS_syscall	0
diff --git a/usr.sbin/rtprio/Makefile b/usr.sbin/rtprio/Makefile
index 2ca8da9..af159bf 100644
--- a/usr.sbin/rtprio/Makefile
+++ b/usr.sbin/rtprio/Makefile
@@ -1,7 +1,11 @@
 #	from: @(#)Makefile	5.5 (Berkeley) 5/11/90
-#	$Id: Makefile,v 1.2 1993/11/23 00:02:21 jtc Exp $
+#	$Id: Makefile,v 1.1 1994/09/01 12:05:12 davidg Exp $
 
 BINDIR=/usr/sbin
 PROG=	rtprio
+LINKS=  ${BINDIR}/rtprio ${BINDIR}/idprio
+MLINKS= rtprio.1 idprio.1
+MAN1=	rtprio.1
+MAN2=	rtprio.2
 
 .include <bsd.prog.mk>
diff --git a/usr.sbin/rtprio/rtprio.1 b/usr.sbin/rtprio/rtprio.1
index a2cc7dc..5542f12 100644
--- a/usr.sbin/rtprio/rtprio.1
+++ b/usr.sbin/rtprio/rtprio.1
@@ -34,35 +34,50 @@
 .Dt RTPRIO 1
 .Os 
 .Sh NAME
-.Nm rtprio
-.Nd execute, examine or modify a process's realtime scheduling priority
+.Nm rtprio ,
+.Nm idprio
+.Nd execute, examine or modify a utilitys or process realtime 
+or idletime scheduling priority
 .Sh SYNOPSIS
 
-.Nm rtprio
-.Nm rtprio 
+.Nm [id|rt]prio
+.Nm [id|rt]prio 
 .Ar pid
-.Nm rtprio 
+.Nm [id|rt]prio 
 .Ar priority
 .Ar command
 .Op args
-.Nm rtprio 
+.Nm [id|rt]prio 
 .Ar priority
 .Ar -pid
-.Nm rtprio 
+.Nm [id|rt]prio 
 .Ar -t
 .Ar command
 .Op args
-.Nm rtprio 
+.Nm [id|rt]prio 
 .Ar -t
 .Ar -pid
 .Sh DESCRIPTION
 .Nm Rtprio
-is used for controlling realtime process scheduling. A process with a
-realtime priority is not subject to priority degradation, and will only
-be preempted by another process of equal or higher realtime priority.
+is used for controlling realtime process scheduling. 
 
-.Nm Rtprio
-called without arguments, will return the realtime priority
+.Nm Idprio
+is used for controlling idletime process scheduling, and can be called
+with the same options as 
+.Nm Rtprio .
+
+A process with a realtime priority is not subject to priority
+degradation, and will only be preempted by another process of equal or
+higher realtime priority.
+
+A process with an idle priority will run only when no other
+process is runnable and then only if it's idle priority is equal or
+greater than all other runnable idle priority processes.
+
+.Nm Rtprio 
+or
+.Nm Idprio 
+when called without arguments will return the realtime priority
 of the current process.
 
 If
@@ -81,23 +96,27 @@ process.
 
 If
 .Ar -pid
-is specified, the process with that pid will be modified, else
-if 
+is specified, the process with the process identifier "pid" will be
+modified, else if
 .Ar command 
 is specified, that program is run with its arguments.
 
 .Ar Priority
-is an integer between 0 (RTPRIO_MIN) and 31 (RTPRIO_MAX). 0 is the
+is an integer between 0 and RTP_PRIO_MAX (usually 31). 0 is the
 highest priority
 
 .Ar Pid
 of 0 means "the current process".
 
-Only root is allowed to set realtime priorities.
+Only root is allowed to set realtime priorities. Non-root processes may
+set idle priority levels for the current process only.
 .Sh RETURN VALUE
+If
 .Nm rtprio
-returns the (new) realtime priority of the process (see rtprio(2)), or
--1 for all usage errors.
+execute a command, the exit value is that of the command executed.
+In all other cases,
+.Nm
+exits with 0 for success and 1 for all other errors.
 .Sh EXAMPLES
 .\LP
 
@@ -131,16 +150,17 @@ To run \fItcpdump\fP without realtime priority:
 .Ed
 
 .\.LP
-To change the realtime priority of process \fI1423\fP to RTRIO_RTOFF
-(no realtime):
+To change the realtime priority of process \fI1423\fP to RTP_PRIO_NORMAL
+(non-realtime/"normal" priority):
 .Bd -literal -offset indent -compact
 \fBrtprio -t -1423\fP
 .Ed
-.Sh DIAGNOSTICS
-The
-.Nm rtprio
-utility shall exit with value of the (new) realtime priority of the
-program.
+
+.\.LP
+To make depend while not disturbing other machine usage:
+.Bd -literal -offset indent -compact
+\fBidprio 31 make depend\fP
+.Ed
 .Sh SEE ALSO
 .Xr rtprio 2 ,
 .Xr nice 1 ,
@@ -153,13 +173,25 @@ The
 utility appeared in
 FreeBSD 2.0,
 but is similar to the HP-UX version.
+.Sh CAVEATS
+You can lock yourself out of the system by placing a cpu-heavy
+process in a realtime priority.
 .Sh BUGS
-You can lock yourself out of the system by placing a cpu-intensive
-process into realtime priority.
-
 There is no way to set/view the realtime priority of process 0
 (swapper) (see ps(1)).
 
+There is in
+FreeBSD
+no way to ensure that a process page is present in memory therefore
+the process may be stopped for pagein. (See mprotect(2), madvise(2)).
+
+Under
+FreeBSD
+system calls are currently never preempted, therefore non-realtime
+processes can starve realtime procesess, or idletime processes can
+starve normal priority processes.
+
 Others ...
 .Sh AUTHOR
-Henrik Vestergaard Draboel - hvd@terry.ping.dk
+Henrik Vestergaard Draboel - hvd@terry.ping.dk is the original author. This
+implementation in FreeBSD was substantially rewritten by David Greenman.
diff --git a/usr.sbin/rtprio/rtprio.2 b/usr.sbin/rtprio/rtprio.2
new file mode 100644
index 0000000..2c1b4c7
--- /dev/null
+++ b/usr.sbin/rtprio/rtprio.2
@@ -0,0 +1,106 @@
+.\" Copyright (c) 1994, Henrik Vestergaard Draboel
+.\" All rights reserved.
+.\" 
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\" 	This product includes software developed by Henrik Vestergaard Draboel.
+.\" 4. The name of the author may not be used to endorse or promote products
+.\"    derived from this software without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\" 
+.\" $Id: rtprio.2,v 1.2 1994/09/01 12:09:17 davidg Exp $
+.\"
+.Dd July 23, 1994
+.Dt RTPRIO 2
+.Sh NAME
+.Nm rtprio
+.Nd examine or modify a process realtime or idle priority
+.Sh SYNOPSIS
+.Fd #include <sys/resource.h>
+.Fd #include <sys/rtprio.h>
+.Ft int 
+.Fn rtprio "function" "pid_t pid" "struct rtprio *rtp"
+.Sh DESCRIPTION
+.Fn rtprio
+is used to lookup or change the realtime or idle priority of a process.
+
+.Fa function
+specifies the operation to be performed. RTP_LOOKUP to lookup the current priority, 
+and RTP_SET to set the priority.
+.Fa pid
+specifies the process to be used, 0 for the current process.
+
+.Fa *rtp
+is a pointer to a struct rtprio which is used to specify the priority and priority type. 
+This structure has the following form:
+.Bd -literal
+struct rtprio {
+	u_short	type;
+	u_short prio;
+};
+.Ed
+.Pp
+The value of the
+.Nm type
+field may be RTP_PRIO_REALTIME for realtime priorities,
+RTP_PRIO_NORMAL for normal priorities, and RTP_PRIO_IDLE for idle priorities.
+The priority specified by the
+.Nm prio
+field ranges between 0 and  
+.Dv RTP_PRIO_MAX (usually 31) .
+0 is the highest possible priority.
+
+Realtime and idle priority is inherited through fork() and exec().
+
+A realtime process can only be preempted by a process of equal or
+higher priority, or by an interrupt; idle priority processes will run only
+when no other real/normal priority process is runnable. Higher real/idle priority processes
+preempt lower real/idle priority processes. Processes of equal real/idle priority are run round-robin.
+.Sh RETURN VALUES
+.Fn rtprio
+will return 0 for success and -1 for all errors. The global variable
+.Va errno
+will be set to indicate the error.
+.Sh ERRORS
+.Fn rtprio
+will fail if 
+.Bl -tag -width Er
+.It Bq Er EINVAL
+The specified
+.Fa prio
+was out of range.
+.It Bq Er EPERM
+The calling process is not allowed to set the realtime priority. Only
+root is allowed to change the realtime priority of any process, and non-root
+may only change the idle priority of the current process.
+.It Bq Er ESRCH
+The specified process was not found.
+.Sh AUTHOR
+The original author was Henrik Vestergaard Draboel - hvd@terry.ping.dk. This
+implementation in FreeBSD was substantially rewritten by David Greenman.
+.Sh SEE ALSO
+.Xr rtprio 1 ,
+.Xr nice 1 ,
+.Xr ps 1 ,
+.Xr nice 2 ,
+.Xr renice 8
+
diff --git a/usr.sbin/rtprio/rtprio.c b/usr.sbin/rtprio/rtprio.c
index cc66fd4..ab4d085 100644
--- a/usr.sbin/rtprio/rtprio.c
+++ b/usr.sbin/rtprio/rtprio.c
@@ -1,5 +1,6 @@
 /*
- * Copyright (c) 1994 The Regents of the University of California.
+ * Copyright (c) 1994 David Greenman
+ * Copyright (c) 1994 Henrik Vestergaard Draboel (hvd@terry.ping.dk)
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -12,16 +13,16 @@
  *    documentation and/or other materials provided with the distribution.
  * 3. All advertising materials mentioning features or use of this software
  *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
+ *	This product includes software developed by Henrik Vestergaard Draboel.
+ *	This product includes software developed by David Greenman.
+ * 4. Neither the names of the authors nor the names of contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
@@ -29,28 +30,15 @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
+ *	$Id$
  */
 
-/* Copyright (c) 1994 Henrik Vestergaard Drabøl (hvd@terry.pping.dk) */
-
-#ifndef lint
-char copyright[] =
-"@(#) Copyright (c) 1989 The Regents of the University of California.\n\
- All rights reserved.\n";
-#endif /* not lint */
-
-#ifndef lint
-/*static char sccsid[] = "from: @(#)rtprio.c	5.4 (Berkeley) 6/1/90";*/
-static char rcsid[] = "$Id: rtprio.c,v 1.2 1993/11/23 00:02:23 jtc Exp $";
-#endif /* not lint */
-
-#include <sys/time.h>
-#include <stdio.h>
+#include <sys/param.h>
 #include <sys/rtprio.h>
-#include <locale.h>
-#include <errno.h>
-#include <err.h>
+#include <sys/errno.h>
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
@@ -60,82 +48,95 @@ static void usage();
 
 int
 main(argc, argv)
-	int argc;
-	char **argv;
+	int     argc;
+	char  **argv;
 {
-	int nrtprio = RTPRIO_RTOFF;
-	int proc=0;
+	char   *p;
+	int     proc = 0;
+	struct rtprio rtp;
+
+	/* find basename */
+	if ((p = rindex(argv[0], '/')) == NULL)
+		p = argv[0];
+	else
+		++p;
 
-	setlocale(LC_ALL, "");
-	errno = 0;
+	if (!strcmp(p, "rtprio"))
+		rtp.type = RTP_PRIO_REALTIME;
+	else if (!strcmp(p, "idprio"))
+		rtp.type = RTP_PRIO_IDLE;
 
 	switch (argc) {
-        case 2:
-	  proc = abs(atoi(argv[1]));
+	case 2:
+		proc = abs(atoi(argv[1]));	/* Should check if numeric
+						 * arg! */
 		/* FALLTHROUGH */
-
 	case 1:
-          nrtprio = rtprio(proc,RTPRIO_NOCHG);
-          fprintf(stderr,"rtprio: %d %s\n",
-            nrtprio,
-            nrtprio==RTPRIO_RTOFF?"(RTOFF)":"");
-          exit(nrtprio); 
-		/* NOTREACHED */
-          
-        default: {
-		switch (argv[1][0]) {
-		case '-':
-		  if (strcmp(argv[1],"-t")==0)
-		       nrtprio = RTPRIO_RTOFF;
-		     else 
-		       usage();
-  		  break;
-
-		case '0':case '1':case '2':case '3':case '4':
-		case '5':case '6':case '7':case '8':case '9':
-		  nrtprio = atoi (argv[1]);
-
-		  if (errno== ERANGE) usage();
-		  break;
-
+		if (rtprio(RTP_LOOKUP, proc, &rtp) != 0) {
+			perror(argv[0]);
+			exit (1);
+		}
+		printf("%s: ", p);
+		switch (rtp.type) {
+		case RTP_PRIO_REALTIME:
+			printf("realtime priority %d\n", rtp.prio);
+			break;
+		case RTP_PRIO_NORMAL:
+			printf("normal priority\n");
+			break;
+		case RTP_PRIO_IDLE:
+			printf("idle priority %d\n", rtp.prio);
+			break;
 		default:
-		  usage(); 
-		  break;
+			printf("invalid priority type %d\n", rtp.type);
+			break;
 		}
-		switch (argv[2][0]) {
-		case '-':
-		  proc = -atoi(argv[2]);
-
-  		break;
+		exit(0);
+	default:
+		if (argv[1][0] == '-' || isdigit(argv[1][0])) {
+			if (argv[1][0] == '-') {
+				if (strcmp(argv[1], "-t") == 0) {
+					rtp.type = RTP_PRIO_NORMAL;
+					rtp.prio = 0;
+				} else {
+					usage(p);
+					break;
+				}
+			} else {
+				rtp.prio = atoi(argv[1]);
+			}
+		} else {
+			usage(p);
+			break;
 		}
-      
-	errno = 0;
 
-        nrtprio = rtprio(proc, nrtprio);
+		if (argv[2][0] == '-')
+			proc = -atoi(argv[2]);
 
-	if (errno) {
-		err (1, "rtprio");
-		/* NOTREACHED */
-	}
+		if (rtprio(RTP_SET, proc, &rtp) != 0) {
+			perror(argv[0]);
+			exit (1);
+		}
 
-	if (proc == 0) {
-          execvp(argv[2], &argv[2]);
-   	  err ((errno == ENOENT) ? 127 : 126, "%s", argv[2]);}
-	  /* NOTREACHED */
-	      }
+		if (proc == 0) {
+			execvp(argv[2], &argv[2]);
+			perror(argv[0]);
+			exit (1);
+		}
 	}
-return(nrtprio);
+	exit (1);
 }
 
 static void
-usage()
+usage(basename)
+	char   *basename;
 {
-	(void)fprintf(stderr, "usage: rtprio\n");
-	(void)fprintf(stderr, "usage: rtprio [-] pid\n");
-	(void)fprintf(stderr, "usage: rtprio priority command [ args ] \n");
-	(void)fprintf(stderr, "usage: rtprio priority -pid \n");
-	(void)fprintf(stderr, "usage: rtprio -t command [ args ] \n");
-	(void)fprintf(stderr, "usage: rtprio -t -pid \n");
-	
+	(void) fprintf(stderr, "usage: %s\n", basename);
+	(void) fprintf(stderr, "usage: %s [-]pid\n", basename);
+	(void) fprintf(stderr, "usage: %s priority command [ args ] \n", basename);
+	(void) fprintf(stderr, "usage: %s priority -pid \n", basename);
+	(void) fprintf(stderr, "usage: %s -t command [ args ] \n", basename);
+	(void) fprintf(stderr, "usage: %s -t -pid \n", basename);
+
 	exit(-1);
 }