Another round of lock pushdown.

Add a simplelock to deal with disable_intr()/enable_intr() as used in UP kernel.
UP kernel expects that this is enough to guarantee exclusive access to
regions of code bracketed by these 2 functions.
Add a simplelock to bracket clock accesses in clock.c: clock_lock.

Help from:	Bruce Evans <bde@zeta.org.au>

2 files changed, 64 insertions, 51 deletions

diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c
index 28f6dc9..0755baf 100644
--- a/sys/isa/atrtc.c
+++ b/sys/isa/atrtc.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)clock.c	7.2 (Berkeley) 5/12/91
- *	$Id: clock.c,v 1.99 1997/08/21 05:08:07 fsmp Exp $
+ *	$Id: clock.c,v 1.10 1997/08/30 01:23:40 smp Exp smp $
  */
 
 /*
@@ -65,9 +65,9 @@
 #include <machine/frame.h>
 #include <machine/ipl.h>
 #include <machine/limits.h>
-#ifdef APIC_IO
+#if defined(SMP) || defined(APIC_IO)
 #include <machine/smp.h>
-#endif /* APIC_IO */
+#endif /* SMP || APIC_IO */
 
 #include <i386/isa/icu.h>
 #include <i386/isa/isa.h>
@@ -77,6 +77,34 @@
 #include <i386/isa/intr_machdep.h>
 #include <sys/interrupt.h>
 
+#ifdef SMP
+#include <machine/smptests.h>
+
+#ifdef SIMPLE_MPINTRLOCK
+#define DISABLE_INTR()					\
+	__asm __volatile("cli" : : : "memory");		\
+ 	s_lock(&clock_lock);
+
+#define ENABLE_INTR()					\
+ 	s_unlock(&clock_lock);				\
+	__asm __volatile("sti");
+
+#define CLOCK_UNLOCK()					\
+ 	s_unlock(&clock_lock);
+#else /* SIMPLE_MPINTRLOCK */
+#define DISABLE_INTR()	disable_intr()
+#define ENABLE_INTR()	enable_intr()
+#define CLOCK_UNLOCK()
+#endif /* SIMPLE_MPINTRLOCK */
+
+#else /* SMP */
+
+#define DISABLE_INTR()	disable_intr()
+#define ENABLE_INTR()	enable_intr()
+#define CLOCK_UNLOCK()
+
+#endif /* SMP */
+
 /*
  * 32-bit time_t's can't reach leap years before 1904 or after 2036, so we
  * can use a simple formula for leap years.
@@ -183,11 +211,11 @@ clkintr(struct clockframe frame)
 		timer0_max_count = TIMER_DIV(new_rate);
 		timer0_overflow_threshold =
 			timer0_max_count - TIMER0_LATCH_COUNT;
-		disable_intr();
+		DISABLE_INTR();
 		outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
 		outb(TIMER_CNTR0, timer0_max_count & 0xff);
 		outb(TIMER_CNTR0, timer0_max_count >> 8);
-		enable_intr();
+		ENABLE_INTR();
 		timer0_prescaler_count = 0;
 		timer_func = new_function;
 		timer0_state = ACQUIRED;
@@ -201,12 +229,12 @@ clkintr(struct clockframe frame)
 			timer0_max_count = hardclock_max_count;
 			timer0_overflow_threshold =
 				timer0_max_count - TIMER0_LATCH_COUNT;
-			disable_intr();
+			DISABLE_INTR();
 			outb(TIMER_MODE,
 			     TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
 			outb(TIMER_CNTR0, timer0_max_count & 0xff);
 			outb(TIMER_CNTR0, timer0_max_count >> 8);
-			enable_intr();
+			ENABLE_INTR();
 			/*
 			 * See microtime.s for this magic.
 			 */
@@ -358,7 +386,7 @@ getit(void)
 	int high, low;
 
 	ef = read_eflags();
-	disable_intr();
+	DISABLE_INTR();
 
 	/* Select timer0 and latch counter value. */
 	outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
@@ -366,6 +394,7 @@ getit(void)
 	low = inb(TIMER_CNTR0);
 	high = inb(TIMER_CNTR0);
 
+	CLOCK_UNLOCK();
 	write_eflags(ef);
 	return ((high << 8) | low);
 }
@@ -480,10 +509,10 @@ sysbeep(int pitch, int period)
 			splx(x);
 			return (-1); /* XXX Should be EBUSY, but nobody cares anyway. */
 		}
-	disable_intr();
+	DISABLE_INTR();
 	outb(TIMER_CNTR2, pitch);
 	outb(TIMER_CNTR2, (pitch>>8));
-	enable_intr();
+	ENABLE_INTR();
 	if (!beeping) {
 		/* enable counter2 output to speaker */
 		outb(IO_PPI, inb(IO_PPI) | 3);
@@ -626,13 +655,14 @@ set_timer_freq(u_int freq, int intr_freq)
 	u_long ef;
 
 	ef = read_eflags();
-	disable_intr();
+	DISABLE_INTR();
 	timer_freq = freq;
 	timer0_max_count = hardclock_max_count = TIMER_DIV(intr_freq);
 	timer0_overflow_threshold = timer0_max_count - TIMER0_LATCH_COUNT;
 	outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
 	outb(TIMER_CNTR0, timer0_max_count & 0xff);
 	outb(TIMER_CNTR0, timer0_max_count >> 8);
+	CLOCK_UNLOCK();
 	write_eflags(ef);
 }
 
@@ -1002,10 +1032,11 @@ set_i586_ctr_freq(u_int i586_freq, u_int i8254_freq)
 			<< I586_CTR_COMULTIPLIER_SHIFT) / i8254_freq;
 	multiplier = (1000000LL << I586_CTR_MULTIPLIER_SHIFT) / i586_freq;
 	ef = read_eflags();
-	disable_intr();
+	DISABLE_INTR();
 	i586_ctr_freq = i586_freq;
 	i586_ctr_comultiplier = comultiplier;
 	i586_ctr_multiplier = multiplier;
+	CLOCK_UNLOCK();
 	write_eflags(ef);
 }
 
diff --git a/sys/isa/sio.c b/sys/isa/sio.c
index 62300b6..7555e2f 100644
--- a/sys/isa/sio.c
+++ b/sys/isa/sio.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)com.c	7.5 (Berkeley) 5/16/91
- *	$Id: sio.c,v 1.5 1997/08/21 06:08:45 smp Exp smp $
+ *	$Id: sio.c,v 1.8 1997/08/30 01:23:40 smp Exp smp $
  */
 
 #include "opt_comconsole.h"
@@ -65,6 +65,11 @@
 #endif
 
 #include <machine/clock.h>
+#ifdef SMP
+#include <machine/smp.h>
+#else
+#define POSTCODE_HI(X)
+#endif
 
 #include <i386/isa/isa.h>
 #include <i386/isa/isa_device.h>
@@ -559,11 +564,11 @@ static int
 card_intr(struct pccard_dev *dp)
 {
 	struct com_s	*com;
-	COM_LOCK();
+	MPINTR_LOCK();
 	com = com_addr(dp->isahd.id_unit);
 	if (com && !com_addr(dp->isahd.id_unit)->gone)
 		siointr1(com_addr(dp->isahd.id_unit));
-	COM_UNLOCK();
+	MPINTR_UNLOCK();
 	return(1);
 }
 #endif /* NCRD > 0 */
@@ -644,7 +649,9 @@ sioprobe(dev)
 	 * but mask them in the processor as well in case there are some
 	 * (misconfigured) shared interrupts.
 	 */
+	POSTCODE_HI(0x8);
 	disable_intr();
+	POSTCODE_HI(0x9);
 /* EXTRA DELAY? */
 
 	/*
@@ -750,7 +757,9 @@ sioprobe(dev)
 		failures[8] = isa_irq_pending(idev) ? 1	: 0;
 	failures[9] = (inb(iobase + com_iir) & IIR_IMASK) - IIR_NOPEND;
 
+	POSTCODE_HI(0xa);
 	enable_intr();
+	POSTCODE_HI(0xb);
 
 	result = IO_COMSIZE;
 	for (fn = 0; fn < sizeof failures; ++fn)
@@ -1185,14 +1194,12 @@ open_top:
 		}
 
 		disable_intr();
-		COM_LOCK();
 		(void) inb(com->line_status_port);
 		(void) inb(com->data_port);
 		com->prev_modem_status = com->last_modem_status
 		    = inb(com->modem_status_port);
 		outb(iobase + com_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS
 				       | IER_EMSC);
-		COM_UNLOCK();
 		enable_intr();
 		/*
 		 * Handle initial DCD.  Callout devices get a fake initial
@@ -1421,9 +1428,9 @@ siointr(unit)
 	int	unit;
 {
 #ifndef COM_MULTIPORT
-	COM_LOCK();
+	MPINTR_LOCK();
 	siointr1(com_addr(unit));
-	COM_UNLOCK();
+	MPINTR_UNLOCK();
 #else /* COM_MULTIPORT */
 	struct com_s    *com;
 	bool_t		possibly_more_intrs;
@@ -1435,11 +1442,15 @@ siointr(unit)
 	 * devices, then the edge from one may be lost because another is
 	 * on.
 	 */
-	COM_LOCK();
+	MPINTR_LOCK();
 	do {
 		possibly_more_intrs = FALSE;
 		for (unit = 0; unit < NSIO; ++unit) {
 			com = com_addr(unit);
+			/*
+			 * XXX MPINTR_LOCK();
+			 * would it work here, or be counter-productive?
+			 */
 			if (com != NULL 
 			    && !com->gone
 			    && (inb(com->int_id_port) & IIR_IMASK)
@@ -1447,9 +1458,10 @@ siointr(unit)
 				siointr1(com);
 				possibly_more_intrs = TRUE;
 			}
+			/* XXX MPINTR_UNLOCK(); */
 		}
 	} while (possibly_more_intrs);
-	COM_UNLOCK();
+	MPINTR_UNLOCK();
 #endif /* COM_MULTIPORT */
 }
 
@@ -1829,7 +1841,6 @@ repeat:
 			 * loop.
 			 */
 			disable_intr();
-			COM_LOCK();
 			incc = com->iptr - com->ibuf;
 			com->iptr = com->ibuf;
 			if (com->state & CS_CHECKMSR) {
@@ -1837,7 +1848,6 @@ repeat:
 				com->state &= ~CS_CHECKMSR;
 			}
 			com_events -= incc;
-			COM_UNLOCK();
 			enable_intr();
 			if (incc != 0)
 				log(LOG_DEBUG,
@@ -1853,7 +1863,6 @@ repeat:
 		} else {
 			buf = ibuf;
 			disable_intr();
-			COM_LOCK();
 			incc = com->iptr - buf;
 			com_events -= incc;
 			if (ibuf == com->ibuf1)
@@ -1874,7 +1883,6 @@ repeat:
 			    && !(tp->t_state & TS_TBLOCK))
 				outb(com->modem_ctl_port,
 				     com->mcr_image |= MCR_RTS);
-			COM_UNLOCK();
 			enable_intr();
 			com->ibuf = ibuf;
 		}
@@ -1883,13 +1891,11 @@ repeat:
 			u_char	delta_modem_status;
 
 			disable_intr();
-			COM_LOCK();
 			delta_modem_status = com->last_modem_status
 					     ^ com->prev_modem_status;
 			com->prev_modem_status = com->last_modem_status;
 			com_events -= LOTS_OF_EVENTS;
 			com->state &= ~CS_CHECKMSR;
-			COM_UNLOCK();
 			enable_intr();
 			if (delta_modem_status & MSR_DCD)
 				(*linesw[tp->t_line].l_modem)
@@ -1897,10 +1903,8 @@ repeat:
 		}
 		if (com->state & CS_ODONE) {
 			disable_intr();
-			COM_LOCK();
 			com_events -= LOTS_OF_EVENTS;
 			com->state &= ~CS_ODONE;
-			COM_UNLOCK();
 			enable_intr();
 			if (!(com->state & CS_BUSY)
 			    && !(com->extra_state & CSE_BUSYCHECK)) {
@@ -2056,11 +2060,9 @@ comparam(tp, t)
 	 * error bits, but that is acceptable here.
 	 */
 	disable_intr();
-	COM_LOCK();
 retry:
 	com->state &= ~CS_TTGO;
 	txtimeout = tp->t_timeout;
-	COM_UNLOCK();
 	enable_intr();
 	while ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
 	       != (LSR_TSRE | LSR_TXRDY)) {
@@ -2077,9 +2079,7 @@ retry:
 		if (error != 0 && error != EAGAIN) {
 			if (!(tp->t_state & TS_TTSTOP)) {
 				disable_intr();
-				COM_LOCK();
 				com->state |= CS_TTGO;
-				COM_UNLOCK();
 				enable_intr();
 			}
 			splx(s);
@@ -2088,7 +2088,6 @@ retry:
 	}
 
 	disable_intr();		/* very important while com_data is hidden */
-	COM_LOCK();
 
 	/*
 	 * XXX - clearing CS_TTGO is not sufficient to stop further output,
@@ -2184,7 +2183,6 @@ retry:
 	if (com->state >= (CS_BUSY | CS_TTGO))
 		siointr1(com);
 
-	COM_UNLOCK();
 	enable_intr();
 	splx(s);
 	comstart(tp);
@@ -2203,7 +2201,6 @@ comstart(tp)
 	com = com_addr(unit);
 	s = spltty();
 	disable_intr();
-	COM_LOCK();
 	if (tp->t_state & TS_TTSTOP)
 		com->state &= ~CS_TTGO;
 	else
@@ -2216,7 +2213,6 @@ comstart(tp)
 		    && com->state & CS_RTS_IFLOW)
 			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
 	}
-	COM_UNLOCK();
 	enable_intr();
 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
 		splx(s);
@@ -2233,7 +2229,6 @@ comstart(tp)
 			com->obufs[0].l_next = NULL;
 			com->obufs[0].l_queued = TRUE;
 			disable_intr();
-			COM_LOCK();
 			if (com->state & CS_BUSY) {
 				qp = com->obufq.l_next;
 				while ((next = qp->l_next) != NULL)
@@ -2245,7 +2240,6 @@ comstart(tp)
 				com->obufq.l_next = &com->obufs[0];
 				com->state |= CS_BUSY;
 			}
-			COM_UNLOCK();
 			enable_intr();
 		}
 		if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {
@@ -2255,7 +2249,6 @@ comstart(tp)
 			com->obufs[1].l_next = NULL;
 			com->obufs[1].l_queued = TRUE;
 			disable_intr();
-			COM_LOCK();
 			if (com->state & CS_BUSY) {
 				qp = com->obufq.l_next;
 				while ((next = qp->l_next) != NULL)
@@ -2267,16 +2260,13 @@ comstart(tp)
 				com->obufq.l_next = &com->obufs[1];
 				com->state |= CS_BUSY;
 			}
-			COM_UNLOCK();
 			enable_intr();
 		}
 		tp->t_state |= TS_BUSY;
 	}
 	disable_intr();
-	COM_LOCK();
 	if (com->state >= (CS_BUSY | CS_TTGO))
 		siointr1(com);	/* fake interrupt to start output */
-	COM_UNLOCK();
 	enable_intr();
 	ttwwakeup(tp);
 	splx(s);
@@ -2293,7 +2283,6 @@ siostop(tp, rw)
 	if (com->gone)
 		return;
 	disable_intr();
-	COM_LOCK();
 	if (rw & FWRITE) {
 		if (com->hasfifo)
 #ifdef COM_ESP
@@ -2322,7 +2311,6 @@ siostop(tp, rw)
 		com_events -= (com->iptr - com->ibuf);
 		com->iptr = com->ibuf;
 	}
-	COM_UNLOCK();
 	enable_intr();
 	comstart(tp);
 }
@@ -2383,7 +2371,6 @@ commctl(com, bits, how)
 	if (com->gone)
 		return(0);
 	disable_intr();
-	COM_LOCK();
 	switch (how) {
 	case DMSET:
 		outb(com->modem_ctl_port,
@@ -2396,7 +2383,6 @@ commctl(com, bits, how)
 		outb(com->modem_ctl_port, com->mcr_image &= ~mcr);
 		break;
 	}
-	COM_UNLOCK();
 	enable_intr();
 	return (0);
 }
@@ -2456,9 +2442,7 @@ comwakeup(chan)
 		if (com != NULL && !com->gone
 		    && (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {
 			disable_intr();
-			COM_LOCK();
 			siointr1(com);
-			COM_UNLOCK();
 			enable_intr();
 		}
 	}
@@ -2482,10 +2466,8 @@ comwakeup(chan)
 			u_long	total;
 
 			disable_intr();
-			COM_LOCK();
 			delta = com->delta_error_counts[errnum];
 			com->delta_error_counts[errnum] = 0;
-			COM_UNLOCK();
 			enable_intr();
 			if (delta == 0)
 				continue;