diff --git a/sys/arch/sparc64/include/cpu.h b/sys/arch/sparc64/include/cpu.h
index d294fff0222a..591c873d0245 100644
--- a/sys/arch/sparc64/include/cpu.h
+++ b/sys/arch/sparc64/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: cpu.h,v 1.77 2008/03/17 04:04:00 nakayama Exp $ */
+/*	$NetBSD: cpu.h,v 1.78 2008/04/03 10:34:45 nakayama Exp $ */
 
 /*
  * Copyright (c) 1992, 1993
@@ -288,10 +288,9 @@ void setsoftnet(void);
 #define	cpu_need_proftick(l)	((l)->l_pflag |= LP_OWEUPC, want_ast = 1)
 
 /*
- * Notify the current process (l) that it has a signal pending,
- * process as soon as possible.
+ * Notify an LWP that it has a signal pending, process as soon as possible.
  */
-#define	cpu_signotify(l)	(want_ast = 1)
+void cpu_signotify(struct lwp *);
 
 /*
  * Interrupt handler chains.  Interrupt handlers should return 0 for
diff --git a/sys/arch/sparc64/sparc64/ipifuncs.c b/sys/arch/sparc64/sparc64/ipifuncs.c
index e117220f89ba..b433cdb3cdab 100644
--- a/sys/arch/sparc64/sparc64/ipifuncs.c
+++ b/sys/arch/sparc64/sparc64/ipifuncs.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ipifuncs.c,v 1.19 2008/03/27 15:20:47 martin Exp $ */
+/*	$NetBSD: ipifuncs.c,v 1.20 2008/04/03 10:34:46 nakayama Exp $ */
 
 /*-
  * Copyright (c) 2004 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ipifuncs.c,v 1.19 2008/03/27 15:20:47 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ipifuncs.c,v 1.20 2008/04/03 10:34:46 nakayama Exp $");
 
 #include "opt_ddb.h"
 
@@ -200,6 +200,7 @@ sparc64_send_ipi(int upaid, ipifunc_t func, uint64_t arg1, uint64_t arg2)
 	int i, ik;
 	uint64_t intr_func;
 
+	KASSERT(upaid != curcpu()->ci_cpuid);
 	if (ldxa(0, ASR_IDSR) & IDSR_BUSY)
 		panic("recursive IPI?");
 
diff --git a/sys/arch/sparc64/sparc64/machdep.c b/sys/arch/sparc64/sparc64/machdep.c
index e28f0c7b51b8..2b5181ab6f79 100644
--- a/sys/arch/sparc64/sparc64/machdep.c
+++ b/sys/arch/sparc64/sparc64/machdep.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: machdep.c,v 1.217 2008/03/14 15:39:18 nakayama Exp $ */
+/*	$NetBSD: machdep.c,v 1.218 2008/04/03 10:34:46 nakayama Exp $ */
 
 /*-
  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
@@ -78,7 +78,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.217 2008/03/14 15:39:18 nakayama Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.218 2008/04/03 10:34:46 nakayama Exp $");
 
 #include "opt_ddb.h"
 #include "opt_multiprocessor.h"
@@ -1969,9 +1969,27 @@ cpu_need_resched(struct cpu_info *ci, int flags)
 	ci->ci_want_resched = 1;
 	ci->ci_want_ast = 1;
 
-#if defined(MULTIPROCESSOR)
+#ifdef MULTIPROCESSOR
+	if (ci == curcpu())
+		return;
 	/* Just interrupt the target CPU, so it can notice its AST */
-	if ((flags & RESCHED_IMMED) || ci->ci_index != cpu_number())
+	if ((flags & RESCHED_IMMED) != 0 &&
+	    ci->ci_data.cpu_onproc != ci->ci_data.cpu_idlelwp)
+		sparc64_send_ipi(ci->ci_cpuid, sparc64_ipi_nop, 0, 0);
+#endif
+}
+
+/*
+ * Notify an LWP that it has a signal pending, process as soon as possible.
+ */
+void
+cpu_signotify(struct lwp *l)
+{
+	struct cpu_info *ci = l->l_cpu;
+
+	ci->ci_want_ast = 1;
+#ifdef MULTIPROCESSOR
+	if (ci != curcpu())
 		sparc64_send_ipi(ci->ci_cpuid, sparc64_ipi_nop, 0, 0);
 #endif
 }