implement reliable microtime on smp (joint work w/ otto):

send a bcast ipi from the cpu0 to all others to timestamp tsc
on every clock intr. this way using local tsc provides accurate
microtime() measurements. thus gettimeofday test passes now.
otto@ deraadt@ ok

4 files changed, 53 insertions, 24 deletions

diff --git a/sys/arch/i386/i386/ipifuncs.c b/sys/arch/i386/i386/ipifuncs.c
index 8d03a5f8707..a90e586dc54 100644
--- a/sys/arch/i386/i386/ipifuncs.c
+++ b/sys/arch/i386/i386/ipifuncs.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipifuncs.c,v 1.5 2006/05/11 13:21:11 mickey Exp $	*/
+/*	$OpenBSD: ipifuncs.c,v 1.6 2006/05/29 09:54:16 mickey Exp $	*/
 /* $NetBSD: ipifuncs.c,v 1.1.2.3 2000/06/26 02:04:06 sommerfeld Exp $ */
 
 /*-
@@ -74,11 +74,7 @@ void i386_ipi_flush_fpu(struct cpu_info *);
 void (*ipifunc[I386_NIPI])(struct cpu_info *) =
 {
 	i386_ipi_halt,
-#if 0 && (defined(I586_CPU) || defined(I686_CPU))
-	cc_microset,
-#else
-	0,
-#endif
+	i386_ipi_microset,
 	i386_ipi_flush_fpu,
 	i386_ipi_synch_fpu,
 	pmap_do_tlb_shootdown,
@@ -158,7 +154,22 @@ i386_self_ipi(int vector)
 void
 i386_broadcast_ipi(int ipimask)
 {
-	panic("broadcast_ipi not implemented");
+	struct cpu_info *ci, *self = curcpu();
+	CPU_INFO_ITERATOR cii;
+	int count = 0;
+
+	CPU_INFO_FOREACH(cii, ci) {
+		if (ci == self)
+			continue;
+		if ((ci->ci_flags & CPUF_RUNNING) == 0)
+			continue;
+		i386_atomic_setbits_l(&ci->ci_ipis, ipimask);
+		count++;
+	}
+	if (!count)
+		return;
+
+	i386_ipi(LAPIC_IPI_VECTOR, LAPIC_DEST_ALLEXCL, LAPIC_DLMODE_FIXED);   
 }
 
 void
diff --git a/sys/arch/i386/i386/lapic.c b/sys/arch/i386/i386/lapic.c
index 8c455833c69..af0c928e53b 100644
--- a/sys/arch/i386/i386/lapic.c
+++ b/sys/arch/i386/i386/lapic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lapic.c,v 1.8 2006/04/27 15:37:51 mickey Exp $	*/
+/*	$OpenBSD: lapic.c,v 1.9 2006/05/29 09:54:16 mickey Exp $	*/
 /* $NetBSD: lapic.c,v 1.1.2.8 2000/02/23 06:10:50 sommerfeld Exp $ */
 
 /*-
@@ -60,6 +60,7 @@
 #include <machine/apicvar.h>
 #include <machine/i82489reg.h>
 #include <machine/i82489var.h>
+#include <machine/pctr.h>
 
 #include <i386/isa/timerreg.h>	/* XXX for TIMER_FREQ */
 
@@ -196,13 +197,19 @@ u_int32_t lapic_per_second;
 u_int32_t lapic_frac_usec_per_cycle;
 u_int64_t lapic_frac_cycle_per_usec;
 u_int32_t lapic_delaytab[26];
+u_int64_t scaled_pentium_mhz;
 
 void
 lapic_clockintr(arg)
 	void *arg;
 {
+	struct cpu_info *ci = curcpu();
 	struct clockframe *frame = arg;
 
+	if (CPU_IS_PRIMARY(ci)) {
+		ci->ci_tscbase = rdtsc();
+		i386_broadcast_ipi(I386_IPI_MICROSET);
+	}
 	hardclock(frame);
 
 	clk_count.ec_count++;
@@ -352,6 +359,8 @@ lapic_calibrate_timer(ci)
 
 		lapic_frac_cycle_per_usec = tmp;
 
+		scaled_pentium_mhz = (1ULL << 32) / pentium_mhz;
+
 		/*
 		 * Compute delay in cycles for likely short delays in usec.
 		 */
@@ -373,7 +382,8 @@ lapic_calibrate_timer(ci)
  * delay for N usec.
  */
 
-void lapic_delay(usec)
+void
+lapic_delay(usec)
 	int usec;
 {
 	int32_t tick, otick;
@@ -401,26 +411,32 @@ void lapic_delay(usec)
 #define LAPIC_TICK_THRESH 200
 
 /*
- * XXX need to make work correctly on other than cpu 0.
+ * An IPI handler to record current timer value
  */
+void
+i386_ipi_microset(struct cpu_info *ci)
+{
+	ci->ci_tscbase = rdtsc();
+}
 
-void lapic_microtime(tv)
+/*
+ * XXX need to make work correctly on other than cpu 0.
+ */
+void
+lapic_microtime(tv)
 	struct timeval *tv;
 {
+	struct cpu_info *ci = curcpu();
 	struct timeval now;
-	u_int32_t tick;
-	u_int32_t usec;
-	u_int32_t tmp;
+	u_int64_t tmp;
 
 	disable_intr();
-	tick = lapic_gettick();
 	now = time;
+	tmp = rdtsc() - ci->ci_tscbase;
 	enable_intr();
 
-	tmp = lapic_tval - tick;
-	usec = ((u_int64_t)tmp * lapic_frac_usec_per_cycle) >> 32;
+	now.tv_usec += (tmp * scaled_pentium_mhz) >> 32;
 
-	now.tv_usec += usec;
 	while (now.tv_usec >= 1000000) {
 		now.tv_sec += 1;
 		now.tv_usec -= 1000000;
diff --git a/sys/arch/i386/include/cpu.h b/sys/arch/i386/include/cpu.h
index 10ce69a46ea..50251739c00 100644
--- a/sys/arch/i386/include/cpu.h
+++ b/sys/arch/i386/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.77 2006/05/19 19:43:41 dim Exp $	*/
+/*	$OpenBSD: cpu.h,v 1.78 2006/05/29 09:54:20 mickey Exp $	*/
 /*	$NetBSD: cpu.h,v 1.35 1996/05/05 19:29:26 christos Exp $	*/
 
 /*-
@@ -114,10 +114,11 @@ struct cpu_info {
 	u_int32_t	ci_imask[NIPL];
 	u_int32_t	ci_iunmask[NIPL];
 
-	paddr_t ci_idle_pcb_paddr;	/* PA of idle PCB */
-	u_long ci_flags;		/* flags; see below */
-	u_int32_t ci_ipis; 		/* interprocessor interrupts pending */
-	int sc_apic_version;  		/* local APIC version */
+	paddr_t		ci_idle_pcb_paddr; /* PA of idle PCB */
+	u_long		ci_flags;	/* flags; see below */
+	u_int32_t	ci_ipis; 	/* interprocessor interrupts pending */
+	int		sc_apic_version;/* local APIC version */
+	u_int64_t	ci_tscbase;
 	
 	u_int32_t	ci_level;
 	u_int32_t	ci_vendor[4];
diff --git a/sys/arch/i386/include/intr.h b/sys/arch/i386/include/intr.h
index 78d079ba87b..242fa7b169c 100644
--- a/sys/arch/i386/include/intr.h
+++ b/sys/arch/i386/include/intr.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: intr.h,v 1.26 2006/03/12 02:04:15 brad Exp $	*/
+/*	$OpenBSD: intr.h,v 1.27 2006/05/29 09:54:20 mickey Exp $	*/
 /*	$NetBSD: intr.h,v 1.5 1996/05/13 06:11:28 mycroft Exp $	*/
 
 /*
@@ -152,6 +152,7 @@ int i386_send_ipi(struct cpu_info *, int);
 void i386_broadcast_ipi(int);
 void i386_multicast_ipi(int, int);
 void i386_ipi_handler(void);
+void i386_ipi_microset(struct cpu_info *);
 void i386_intlock(int);
 void i386_intunlock(int);
 void i386_softintlock(void);