From afd64316c869eb00dde4d6b4af61bca0cb2197f1 Mon Sep 17 00:00:00 2001
From: Mark Johnston <markj@FreeBSD.org>
Date: Tue, 17 Feb 2026 17:37:42 +0000
Subject: [PATCH] dtrace: Implement ustackdepth for arm64

MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D52475
---
 sys/cddl/dev/dtrace/aarch64/dtrace_isa.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c b/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c
index ff0e068006b..037d4734659 100644
--- a/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c
+++ b/sys/cddl/dev/dtrace/aarch64/dtrace_isa.c
@@ -228,10 +228,22 @@ dtrace_getupcstack(uint64_t *pcstack, int pcstack_limit)
 int
 dtrace_getustackdepth(void)
 {
+	proc_t *p = curproc;
+	struct trapframe *tf;
+	uintptr_t pc, fp;
+	int n = 0;
 
-	printf("IMPLEMENT ME: %s\n", __func__);
+	if (p == NULL || (tf = curthread->td_frame) == NULL)
+		return (0);
 
-	return (0);
+	if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT))
+		return (-1);
+
+	pc = tf->tf_elr;
+	fp = tf->tf_x[29];
+	n += dtrace_getustack_common(NULL, 0, pc, fp);
+
+	return (n);
 }
 
 void