From f03ce73820cb2fc346aec604d2e1391b4be561c2 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Wed, 26 Feb 2003 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2003-02-26

---
 pc/vgas3.c       |  8 ++++++++
 pc/vgasavage.c   |  9 ++++++---
 port/devproc.c   | 10 ----------
 port/portclock.c | 18 ++++++++++++++++--
 port/proc.c      |  3 +--
 5 files changed, 31 insertions(+), 17 deletions(-)

diff --git a/pc/vgas3.c b/pc/vgas3.c
index 8436b9e5972f263c3978b3c28b41e8cc79311d3c..dc2d6b5d3521bad0535caa5b41a87abe1bc84433 100644
--- a/pc/vgas3.c
+++ b/pc/vgas3.c
@@ -18,6 +18,8 @@ enum {
 	SAVAGE3D	= 0x8A20,	/* PCI DID */
 	SAVAGE3DMV	= 0x8A21,
 	SAVAGE4		= 0x8A22,
+	PROSAVAGEP	= 0x8A25,
+	PROSAVAGEK	= 0x8A26,
 	SAVAGEMXMV	= 0x8C10,
 	SAVAGEMX	= 0x8C11,
 	SAVAGEIXMV	= 0x8C12,
@@ -127,6 +129,8 @@ s3linear(VGAscr* scr, int* size, int* align)
 		id = (vgaxi(Crtx, 0x2D)<<8)|vgaxi(Crtx, 0x2E);
 		switch(id){			/* find mmio */
 		case SAVAGE4:
+		case PROSAVAGEP:
+		case PROSAVAGEK:
 		case SUPERSAVAGEIXC16:
 			/*
 			 * We could assume that the MMIO registers
@@ -227,6 +231,8 @@ s3load(VGAscr* scr, Cursor* curs)
 	case SAVAGEMXMV:
 	case SAVAGEIXMV:
 	case SAVAGE4:
+	case PROSAVAGEP:
+	case PROSAVAGEK:
 	case SUPERSAVAGEIXC16:
 		dolock = 0;
 		p += scr->storage;
@@ -577,6 +583,8 @@ s3drawinit(VGAscr *scr)
 		break;
 	case SUPERSAVAGEIXC16:
 	case SAVAGE4:
+	case PROSAVAGEP:
+	case PROSAVAGEK:
 		/* scr->mmio is set by s3linear */
 		savageinit(scr);
 		break;
diff --git a/pc/vgasavage.c b/pc/vgasavage.c
index b2a183cfe8e722488ebe300d55aeb0231575a0ec..ceffbb9cc4a630839aa08598a213ba6621dab133 100644
--- a/pc/vgasavage.c
+++ b/pc/vgasavage.c
@@ -18,7 +18,8 @@ enum {
 	SAVAGE3D	= 0x8A20,	/* PCI DID */
 	SAVAGE3DMV	= 0x8A21,
 	SAVAGE4		= 0x8A22,
-	SAVAGE4A	= 0x8A26,
+	PROSAVAGEP	= 0x8A25,
+	PROSAVAGEK	= 0x8A26,
 	SAVAGEMXMV	= 0x8C10,
 	SAVAGEMX	= 0x8C11,
 	SAVAGEIXMV	= 0x8C12,
@@ -363,7 +364,8 @@ savagewaitidle(VGAscr *scr)
 
 	switch(scr->id){
 	case SAVAGE4:
-	case SAVAGE4A:
+	case PROSAVAGEP:
+	case PROSAVAGEK:
 		/* wait for engine idle and FIFO empty */
 		statw = (ulong*)((uchar*)scr->mmio+AltStatus0);
 		mask = CBEMask | Ge2Idle;
@@ -492,7 +494,8 @@ savageinit(VGAscr *scr)
 	/* if you add chip IDs here be sure to update savagewaitidle */
 	switch(scr->id){
 	case SAVAGE4:
-	case SAVAGE4A:
+	case PROSAVAGEP:
+	case PROSAVAGEK:
 	case SAVAGEIXMV:
 	case SUPERSAVAGEIXC16:
 	case SAVAGEMXMV:
diff --git a/port/devproc.c b/port/devproc.c
index 22481649b6e993b621ebe0c3b4474d2fd867c2bd..124d3be2be78388c8ca1ade7700020a577fe13a0 100644
--- a/port/devproc.c
+++ b/port/devproc.c
@@ -1197,16 +1197,6 @@ procctlreq(Proc *p, char *va, int n)
 	case CMwired:
 		procwired(p, atoi(cb->f[1]));
 		break;
-	case CMfair:
-		if(!iseve())
-			error(Eperm);
-		unfair = 0;
-		break;
-	case CMunfair:
-		if(!iseve())
-			error(Eperm);
-		unfair = 1;
-		break;
 	}
 
 	poperror();
diff --git a/port/portclock.c b/port/portclock.c
index 6fc0b060bc4caf3fdba6e1a7253d0e7560095b6a..9da9eeda5c3c9f56bd07d0bb318f2cdf617dc4a7 100644
--- a/port/portclock.c
+++ b/port/portclock.c
@@ -95,6 +95,8 @@ timerdel(Timer *dt)
 void
 hzclock(Ureg *ur)
 {
+	int callsched;
+
 	m->ticks++;
 	if(m->proc)
 		m->proc->pc = ur->pc;
@@ -124,8 +126,20 @@ hzclock(Ureg *ur)
 	if(up == 0 || up->state != Running)
 		return;
 
-	/* i.e. don't deschedule an EDF process here! */
-	if(anyready() && !edf->isedf(up)){
+	if(up->fixedpri){
+		/*  fixed priority processes are only preempted by
+		 *  higher piority processes.
+		 */
+		if(anyhigher())
+			callsched = 1;
+	} else {
+		/*  floating priority processes are are preempted
+		 *  by all sorts of things.
+		 */
+		if(anyready() && !edf->isedf(up))
+			callsched = 1;
+	}
+	if(callsched){
 		sched();
 		splhi();
 	}
diff --git a/port/proc.c b/port/proc.c
index 8d999a68590729d5d7802be1f3ba305dacd36ef2..27e3322a5b776311f66119c488e0685957375393 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -9,7 +9,6 @@ int	nrdy;
 Ref	noteidalloc;
 
 long	delayedscheds;	/* statistics */
-int unfair;			/* unfair scheduling */
 
 static Ref	pidalloc;
 
@@ -229,7 +228,7 @@ loop:
 	 */
 	spllo();
 	for(;;){
-		if(!unfair && (++(m->fairness) & 0x3) == 0){
+		if((++(m->fairness) & 0x3) == 0){
 			/*
 			 *  once in a while, run process that's been waiting longest
 			 *  regardless of movetime