kernel: cleanup exit()/shutdown()/reboot() code

introduce cpushutdown() function that does the common
operation of initiating shutdown, returning once all
cpu's got the message and are about to shutdown. this
avoids duplicated code which isnt really machine specific.

automatic reboot on panic only when *debug= is not set
and the machine is a cpu server or has no display,
otherwise just hang.

2 files changed, 3 insertions, 68 deletions

diff --git a/sys/src/9/teg2/dat.h b/sys/src/9/teg2/dat.h
index 83420dfbd..80068975c 100644
--- a/sys/src/9/teg2/dat.h
+++ b/sys/src/9/teg2/dat.h
@@ -250,7 +250,6 @@ struct
 	int	wfi;			/* bitmap of CPUs in WFI state */
 	int	stopped;		/* bitmap of CPUs stopped */
 	int	exiting;		/* shutdown */
-	int	ispanic;		/* shutdown in response to a panic */
 	int	thunderbirdsarego;	/* lets the added processors continue to schedinit */
 }active;
 
diff --git a/sys/src/9/teg2/main.c b/sys/src/9/teg2/main.c
index f5feced0a..6847f3a91 100644
--- a/sys/src/9/teg2/main.c
+++ b/sys/src/9/teg2/main.c
@@ -480,51 +480,13 @@ main(void)
 	panic("cpu%d: schedinit returned", m->machno);
 }
 
-static void
-shutdown(int ispanic)
-{
-	int ms, once;
-
-	lock(&active);
-	if(ispanic)
-		active.ispanic = ispanic;
-	else if(m->machno == 0 && (active.machs & (1<<m->machno)) == 0)
-		active.ispanic = 0;
-	once = active.machs & (1<<m->machno);
-	/*
-	 * setting exiting will make hzclock() on each processor call exit(0),
-	 * which calls shutdown(0) and idles non-bootstrap cpus and returns
-	 * on bootstrap processors (to permit a reboot).  clearing our bit
-	 * in machs avoids calling exit(0) from hzclock() on this processor.
-	 */
-	active.machs &= ~(1<<m->machno);
-	active.exiting = 1;
-	unlock(&active);
-
-	if(once) {
-		delay(m->machno*1000);		/* stagger them */
-		iprint("cpu%d: exiting\n", m->machno);
-	}
-	spllo();
-	if (m->machno == 0)
-		ms = 5*1000;
-	else
-		ms = 2*1000;
-	for(; ms > 0; ms -= TK2MS(2)){
-		delay(TK2MS(2));
-		if(active.machs == 0 && consactive() == 0)
-			break;
-	}
-	delay(500);
-}
-
 /*
  *  exit kernel either on a panic or user request
  */
 void
-exit(int code)
+exit(int)
 {
-	shutdown(code);
+	cpushutdown();
 	splhi();
 	if (m->machno == 0)
 		archreboot();
@@ -576,10 +538,8 @@ isaconfig(char *class, int ctlrno, ISAConf *isa)
 void
 reboot(void *entry, void *code, ulong size)
 {
-	int cpu, nmach, want, ms;
 	void (*f)(ulong, ulong, ulong);
 
-	nmach = conf.nmach;
 	writeconf();
 
 	/*
@@ -590,33 +550,12 @@ reboot(void *entry, void *code, ulong size)
 		procwired(up, 0);
 		sched();
 	}
-	if (m->machno != 0)
-		print("on cpu%d (not 0)!\n", m->machno);
-
-	/*
-	 * the other cpus could be holding locks that will never get
-	 * released (e.g., in the print path) if we put them into
-	 * reset now, so force them to shutdown gracefully first.
-	 */
-	for (want = 0, cpu = 1; cpu < navailcpus; cpu++)
-		want |= 1 << cpu;
-	active.stopped = 0;
-	shutdown(0);
-	for (ms = 15*1000; ms > 0 && active.stopped != want; ms -= 10)
-		delay(10);
-	delay(20);
-	if (active.stopped != want) {
-		for (cpu = 1; cpu < nmach; cpu++)
-			stopcpu(cpu);		/* make really sure */
-		delay(20);
-	}
+	cpushutdown();
 
 	/*
 	 * should be the only processor running now
 	 */
 	pcireset();
-//	print("reboot entry %#lux code %#lux size %ld\n",
-//		PADDR(entry), PADDR(code), size);
 
 	/* turn off buffered serial console */
 	serialoq = nil;
@@ -642,9 +581,6 @@ reboot(void *entry, void *code, ulong size)
 
 	/* off we go - never to return */
 	(*f)(PADDR(entry), PADDR(code), size);
-
-	iprint("loaded kernel returned!\n");
-	archreboot();
 }
 
 /*