diff --git a/sys/arch/alpha/alpha/interrupt.c b/sys/arch/alpha/alpha/interrupt.c
index 7bcbee2c0eb5..444d882edfff 100644
--- a/sys/arch/alpha/alpha/interrupt.c
+++ b/sys/arch/alpha/alpha/interrupt.c
@@ -1,4 +1,4 @@
-/* $NetBSD: interrupt.c,v 1.46 2000/06/03 20:47:36 thorpej Exp $ */
+/* $NetBSD: interrupt.c,v 1.47 2000/06/04 03:40:03 thorpej Exp $ */
 
 /*-
  * Copyright (c) 2000 The NetBSD Foundation, Inc.
@@ -79,7 +79,7 @@
 
 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
 
-__KERNEL_RCSID(0, "$NetBSD: interrupt.c,v 1.46 2000/06/03 20:47:36 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: interrupt.c,v 1.47 2000/06/04 03:40:03 thorpej Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -166,6 +166,8 @@ interrupt(unsigned long a0, unsigned long a1, unsigned long a2,
 	    {
 		u_long pending_ipis, bit;
 
+		atomic_add_ulong(&ci->ci_intrdepth, 1);
+
 #if 0
 		printf("CPU %lu got IPI\n", cpu_id);
 #endif
@@ -190,6 +192,8 @@ interrupt(unsigned long a0, unsigned long a1, unsigned long a2,
 		if (ci->ci_cpuid == hwrpb->rpb_primary_cpu_id &&
 		    hwrpb->rpb_txrdy != 0)
 			cpu_iccb_receive();
+
+		atomic_sub_ulong(&ci->ci_intrdepth, 1);
 	    }
 #else
 		printf("WARNING: received interprocessor interrupt!\n");
@@ -197,6 +201,12 @@ interrupt(unsigned long a0, unsigned long a1, unsigned long a2,
 		break;
 		
 	case ALPHA_INTR_CLOCK:	/* clock interrupt */
+		/*
+		 * We don't increment the interrupt depth for the
+		 * clock interrupt, since it is *sampled* from
+		 * the clock interrupt, so if we did, all system
+		 * time would be counted as interrupt time.
+		 */
 #if defined(MULTIPROCESSOR)
 		/* XXX XXX XXX */
 		if (CPU_IS_PRIMARY(ci) == 0)
@@ -223,11 +233,13 @@ interrupt(unsigned long a0, unsigned long a1, unsigned long a2,
 		break;
 
 	case ALPHA_INTR_ERROR:	/* Machine Check or Correctable Error */
+		atomic_add_ulong(&ci->ci_intrdepth, 1);
 		a0 = alpha_pal_rdmces();
 		if (platform.mcheck_handler)
 			(*platform.mcheck_handler)(a0, framep, a1, a2);
 		else
 			machine_check(a0, framep, a1, a2);
+		atomic_sub_ulong(&ci->ci_intrdepth, 1);
 		break;
 
 	case ALPHA_INTR_DEVICE:	/* I/O device interrupt */
@@ -236,9 +248,11 @@ interrupt(unsigned long a0, unsigned long a1, unsigned long a2,
 		if (CPU_IS_PRIMARY(ci) == 0)
 			return;
 #endif
+		atomic_add_ulong(&ci->ci_intrdepth, 1);
 		uvmexp.intrs++;
 		if (platform.iointr)
 			(*platform.iointr)(framep, a1);
+		atomic_sub_ulong(&ci->ci_intrdepth, 1);
 		break;
 
 	case ALPHA_INTR_PERF:	/* performance counter interrupt */
diff --git a/sys/arch/alpha/include/cpu.h b/sys/arch/alpha/include/cpu.h
index 3226364fb1b9..72145f066a20 100644
--- a/sys/arch/alpha/include/cpu.h
+++ b/sys/arch/alpha/include/cpu.h
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu.h,v 1.41 2000/06/03 20:47:40 thorpej Exp $ */
+/* $NetBSD: cpu.h,v 1.42 2000/06/04 03:40:04 thorpej Exp $ */
 
 /*-
  * Copyright (c) 1998, 1999, 2000 The NetBSD Foundation, Inc.
@@ -128,6 +128,7 @@ struct cpu_info {
 	struct device *ci_dev;		/* pointer to our device */
 	u_long ci_want_resched;		/* preempt current process */
 	u_long ci_astpending;		/* AST is pending */
+	u_long ci_intrdepth;		/* interrupt trap depth */
 #if defined(MULTIPROCESSOR)
 	u_long ci_flags;		/* flags; see below */
 	u_long ci_ipis;			/* interprocessor interrupts pending */
@@ -179,11 +180,13 @@ struct clockframe {
 #define	CLKF_BASEPRI(framep)						\
 	(((framep)->cf_tf.tf_regs[FRAME_PS] & ALPHA_PSL_IPL_MASK) == 0)
 #define	CLKF_PC(framep)		((framep)->cf_tf.tf_regs[FRAME_PC])
+
 /*
- * XXX No way to accurately tell if we were in interrupt mode before taking
- * clock interrupt.
+ * This isn't perfect; if the clock interrupt comes in before the
+ * r/m/w cycle is complete, we won't be counted... but it's not
+ * like this stastic has to be extremely accurate.
  */
-#define	CLKF_INTR(framep)	(0)
+#define	CLKF_INTR(framep)	(curcpu()->ci_intrdepth)
 
 /*
  * Preempt the current process if in interrupt from user mode,