diff --git a/sys/dev/hwpmc/hwpmc_arm.c b/sys/dev/hwpmc/hwpmc_arm.c
index af905b66924e..160be9afe054 100644
--- a/sys/dev/hwpmc/hwpmc_arm.c
+++ b/sys/dev/hwpmc/hwpmc_arm.c
@@ -38,3 +38,23 @@ pmc_md_initialize()
 {
 	return NULL;
 }
+
+int
+pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
+
+int
+pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
diff --git a/sys/dev/hwpmc/hwpmc_ia64.c b/sys/dev/hwpmc/hwpmc_ia64.c
index af905b66924e..160be9afe054 100644
--- a/sys/dev/hwpmc/hwpmc_ia64.c
+++ b/sys/dev/hwpmc/hwpmc_ia64.c
@@ -38,3 +38,23 @@ pmc_md_initialize()
 {
 	return NULL;
 }
+
+int
+pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
+
+int
+pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
diff --git a/sys/dev/hwpmc/hwpmc_powerpc.c b/sys/dev/hwpmc/hwpmc_powerpc.c
index af905b66924e..160be9afe054 100644
--- a/sys/dev/hwpmc/hwpmc_powerpc.c
+++ b/sys/dev/hwpmc/hwpmc_powerpc.c
@@ -38,3 +38,23 @@ pmc_md_initialize()
 {
 	return NULL;
 }
+
+int
+pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
+
+int
+pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
diff --git a/sys/dev/hwpmc/hwpmc_sparc64.c b/sys/dev/hwpmc/hwpmc_sparc64.c
index af905b66924e..160be9afe054 100644
--- a/sys/dev/hwpmc/hwpmc_sparc64.c
+++ b/sys/dev/hwpmc/hwpmc_sparc64.c
@@ -38,3 +38,23 @@ pmc_md_initialize()
 {
 	return NULL;
 }
+
+int
+pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}
+
+int
+pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
+    struct trapframe *tf)
+{
+	(void) cc;
+	(void) maxsamples;
+	(void) tf;
+	return (0);
+}