From 0895365659e3318b8d2ce6c29a362b5378564f8d Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Wed, 27 Jul 1994 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1994-07-27

---
 port/portdat.h |  2 ++
 port/proc.c    | 14 +++++++++-----
 port/sysproc.c |  5 +++++
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/port/portdat.h b/port/portdat.h
index afec73e1f3cf6e34bac5a6c6b7611fff44947786..f6bdaa6e3f573e0c448ae8942a05a1794cfbe4f6 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -579,6 +579,7 @@ struct Proc
 	Mach	*mp;		/* machine this process last ran on */
 	ulong	affinity;	/* affinity counter for that mach */
 	ulong	movetime;	/* ticks when proc was last reassigned */
+	ulong	priority;
 
 	void	*ureg;		/* User registers for notes */
 	void	*dbgreg;	/* User registers for devproc */
@@ -689,3 +690,4 @@ extern int mouseshifted;
 extern int mousetype;
 extern int mouseswap;
 extern int nsyscall;
+extern Physseg physseg[];
diff --git a/port/proc.c b/port/proc.c
index 703a8865ca221609b07c213f6403678052a0c87f..4fd3ecf952663f4502f9da7fa817ca15563d8a7b 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -22,7 +22,7 @@ struct
 }waitqalloc;
 
 int	nrdy;
-Schedq	runhiq;
+Schedq	runhiq;		/* for hi priority process, don't bother with affinity */
 
 char *statename[] =
 {			/* BUG: generate automatically */
@@ -113,7 +113,9 @@ ready(Proc *p)
 
 	s = splhi();
 
-	if(p->state == Running)
+	if(p->priority)
+		rq = &runhiq;
+	else if(p->state == Running)
 		rq = &balance(p)->loq;
 	else
 		rq = &affinity(p)->hiq;
@@ -140,16 +142,18 @@ runproc(void)
 
 loop:
 	spllo();
-	while(m->hiq.head == 0 && m->loq.head == 0)
+	while(runhiq.head == 0 && m->hiq.head == 0 && m->loq.head == 0)
 		;
 	splhi();
 
-	if(m->hiq.head)
+	lock(&runhiq);
+	if(runhiq.head)
+		rq = &runhiq;
+	else if(m->hiq.head)
 		rq = &m->hiq;
 	else
 		rq = &m->loq;
 
-	lock(&runhiq);
 	p = rq->head;
 	/* p->mach==0 only when process state is saved */
 	if(p == 0 || p->mach){	
diff --git a/port/sysproc.c b/port/sysproc.c
index a9a55bcba9b715d5432ed5bd8bee6b84afdd4180..f877e7bc4c419ad95ea5aea26b07664f5dc12338 100644
--- a/port/sysproc.c
+++ b/port/sysproc.c
@@ -380,6 +380,11 @@ sysexec(ulong *arg)
 	s->top = USTKTOP;
 	relocateseg(s, USTKTOP-TSTKTOP);
 
+	/*
+	 *  '/' processes are high priority (hack to make /ip more responsive)
+	 */
+	if(devchar[tc->type] == L'/')
+		up->priority = 1;
 	close(tc);
 
 	/*