zephyrproject-rtos · nashif · Jul 30, 2025 · Jul 29, 2025 · Jul 30, 2025 · Jul 30, 2025
diff --git a/include/zephyr/tracing/tracing.h b/include/zephyr/tracing/tracing.h
@@ -876,14 +876,14 @@
  * @brief Trace Conditional Variable wait enter
  * @param condvar Conditional Variable object
  */
-#define sys_port_trace_k_condvar_wait_enter(condvar)
+#define sys_port_trace_k_condvar_wait_enter(condvar, timeout)
 
 /**
  * @brief Trace Conditional Variable wait exit
  * @param condvar Conditional Variable object
  * @param ret Return value
  */
-#define sys_port_trace_k_condvar_wait_exit(condvar, ret)
+#define sys_port_trace_k_condvar_wait_exit(condvar, timeout, ret)
 
 /** @} */ /* end of subsys_tracing_apis_condvar */
 

diff --git a/kernel/condvar.c b/kernel/condvar.c
@@ -117,15 +117,15 @@ int z_impl_k_condvar_wait(struct k_condvar *condvar, struct k_mutex *mutex,
 	k_spinlock_key_t key;
 	int ret;
 
-	SYS_PORT_TRACING_OBJ_FUNC_ENTER(k_condvar, wait, condvar);
+	SYS_PORT_TRACING_OBJ_FUNC_ENTER(k_condvar, wait, condvar, timeout);
 
 	key = k_spin_lock(&lock);
 	k_mutex_unlock(mutex);
 
 	ret = z_pend_curr(&lock, key, &condvar->wait_q, timeout);
 	k_mutex_lock(mutex, K_FOREVER);
 
-	SYS_PORT_TRACING_OBJ_FUNC_EXIT(k_condvar, wait, condvar, ret);
+	SYS_PORT_TRACING_OBJ_FUNC_EXIT(k_condvar, wait, condvar, timeout, ret);
 
 	return ret;
 }

diff --git a/kernel/msg_q.c b/kernel/msg_q.c
@@ -89,7 +89,6 @@ int z_impl_k_msgq_alloc_init(struct k_msgq *msgq, size_t msg_size,
 	}
 
 	SYS_PORT_TRACING_OBJ_FUNC_EXIT(k_msgq, alloc_init, msgq, ret);
-
 	return ret;
 }
 
@@ -106,22 +105,22 @@ int z_vrfy_k_msgq_alloc_init(struct k_msgq *msgq, size_t msg_size,
 
 int k_msgq_cleanup(struct k_msgq *msgq)
 {
+	int ret = 0;
 	SYS_PORT_TRACING_OBJ_FUNC_ENTER(k_msgq, cleanup, msgq);
 
 	CHECKIF(z_waitq_head(&msgq->wait_q) != NULL) {
-		SYS_PORT_TRACING_OBJ_FUNC_EXIT(k_msgq, cleanup, msgq, -EBUSY);
-
-		return -EBUSY;
+		ret = -EBUSY;
+		goto exit;
 	}
 
 	if ((msgq->flags & K_MSGQ_FLAG_ALLOC) != 0U) {
 		k_free(msgq->buffer_start);
 		msgq->flags &= ~K_MSGQ_FLAG_ALLOC;
 	}
 
-	SYS_PORT_TRACING_OBJ_FUNC_EXIT(k_msgq, cleanup, msgq, 0);
-
-	return 0;
+exit:
+	SYS_PORT_TRACING_OBJ_FUNC_EXIT(k_msgq, cleanup, msgq, ret);
+	return ret;
 }
 
 static inline int put_msg_in_queue(struct k_msgq *msgq, const void *data,

diff --git a/snippets/semihost-tracing/README.rst b/snippets/semihost-tracing/README.rst
@@ -0,0 +1,67 @@
+.. _snippet-semihost-tracing:
+
+Semihost Tracing Snippet (semihost-tracing)
+###########################################
+
+.. code-block:: console
+
+   west build -S semihost-tracing [...]
+
+Overview
+********
+
+This snippet enables CTF Tracing using semihosting on a target that supports it.
+
+Using Qemu, you can run the example application and generate a CTF trace file
+using semihosting. The trace file can then be viewed using `Babeltrace`_.
+
+.. code-block:: console
+
+   (gdb) dump binary memory ram_tracing.bin ram_tracing ram_tracing+8192
+
+Using `Babeltrace`_, you can view the binary file as a CTF trace:
+
+.. code-block:: console
+
+   [19:00:00.023530800] (+?.?????????) thread_create: { thread_id = 2147621216, name = "unknown" }
+   [19:00:00.023567100] (+0.000036300) thread_info: { thread_id = 2147621216, name = "unknown", stack_base = 2147705856, stack_size = 3072 }
+   [19:00:00.023673700] (+0.000106600) thread_name_set: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.023731100] (+0.000057400) thread_wakeup: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.023827500] (+0.000096400) thread_switched_out: { thread_id = 2147621968, name = "main" }
+   [19:00:00.023904500] (+0.000077000) thread_switched_in: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.024807600] (+0.000903100) thread_create: { thread_id = 2147619320, name = "unknown" }
+   [19:00:00.024843800] (+0.000036200) thread_info: { thread_id = 2147619320, name = "unknown", stack_base = 2147693568, stack_size = 3072 }
+   [19:00:00.024898700] (+0.000054900) thread_wakeup: { thread_id = 2147619320, name = "unknown" }
+   [19:00:00.025020000] (+0.000121300) thread_switched_out: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.025130700] (+0.000110700) thread_switched_in: { thread_id = 2147621968, name = "main" }
+   [19:00:00.025249900] (+0.000119200) thread_switched_out: { thread_id = 2147621968, name = "main" }
+   [19:00:00.025353500] (+0.000103600) thread_switched_in: { thread_id = 2147619320, name = "unknown" }
+   [19:00:00.026049900] (+0.000696400) thread_switched_in: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.026759200] (+0.000709300) semaphore_give_enter: { id = 2147735664 }
+   [19:00:00.026773600] (+0.000014400) semaphore_give_exit: { id = 2147735664 }
+   [19:00:00.027346600] (+0.000573000) thread_switched_out: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.027457400] (+0.000110800) thread_switched_in: { thread_id = 2147621968, name = "main" }
+   [19:00:00.029552800] (+0.002095400) thread_create: { thread_id = 2147621216, name = "unknown" }
+   [19:00:00.029589000] (+0.000036200) thread_info: { thread_id = 2147621216, name = "unknown", stack_base = 2147705856, stack_size = 3072 }
+   [19:00:00.029697400] (+0.000108400) thread_name_set: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.029754800] (+0.000057400) thread_wakeup: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.029851200] (+0.000096400) thread_switched_out: { thread_id = 2147621968, name = "main" }
+   [19:00:00.029928200] (+0.000077000) thread_switched_in: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.029968400] (+0.000040200) semaphore_init: { id = 2147623436, ret = 0 }
+   [19:00:00.030851900] (+0.000883500) thread_create: { thread_id = 2147619320, name = "unknown" }
+   [19:00:00.030888100] (+0.000036200) thread_info: { thread_id = 2147619320, name = "unknown", stack_base = 2147693568, stack_size = 3072 }
+   [19:00:00.030943000] (+0.000054900) thread_wakeup: { thread_id = 2147619320, name = "unknown" }
+   [19:00:00.030989600] (+0.000046600) semaphore_take_enter: { id = 2147623436, timeout = 4294957296 }
+   [19:00:00.031005800] (+0.000016200) semaphore_take_blocking: { id = 2147623436, timeout = 4294957296 }
+   [19:00:00.031099600] (+0.000093800) thread_switched_out: { thread_id = 2147621216, name = "test_abort_from_isr" }
+   [19:00:00.031210300] (+0.000110700) thread_switched_in: { thread_id = 2147621968, name = "main" }
+   [19:00:00.031329500] (+0.000119200) thread_switched_out: { thread_id = 2147621968, name = "main" }
+   [19:00:00.031433100] (+0.000103600) thread_switched_in: { thread_id = 2147619320, name = "unknown" }
+   [19:00:00.031469100] (+0.000036000) semaphore_give_enter: { id = 2147623436 }
+
+References
+**********
+
+.. target-notes::
+
+.. _Babeltrace: https://babeltrace.org/
diff --git a/snippets/semihost-tracing/semihost-tracing.conf b/snippets/semihost-tracing/semihost-tracing.conf
@@ -0,0 +1,12 @@
+# Copyright Zephyr Project Contributors
+# SPDX-License-Identifier: Apache-2.0
+
+
+CONFIG_DEBUG_OPTIMIZATIONS=n
+CONFIG_DEBUG_THREAD_INFO=y
+
+CONFIG_TRACING=y
+CONFIG_TRACING_CTF=y
+CONFIG_TRACING_BACKEND_SEMIHOST=y
+CONFIG_SEMIHOST=y
+CONFIG_TRACING_SYNC=y
diff --git a/snippets/semihost-tracing/snippet.yml b/snippets/semihost-tracing/snippet.yml
@@ -0,0 +1,6 @@
+# Copyright Zephyr Project Contributors
+# SPDX-License-Identifier: Apache-2.0
+
+name: semihost-tracing
+append:
+  EXTRA_CONF_FILE: semihost-tracing.conf
diff --git a/subsys/tracing/CMakeLists.txt b/subsys/tracing/CMakeLists.txt
@@ -22,6 +22,11 @@ zephyr_sources_ifdef(
   tracing_backend_usb.c
   )
 
+zephyr_sources_ifdef(
+  CONFIG_TRACING_BACKEND_SEMIHOST
+  tracing_backend_semihosting.c
+  )
+
 zephyr_sources_ifdef(
   CONFIG_TRACING_BACKEND_UART
   tracing_backend_uart.c

diff --git a/subsys/tracing/Kconfig b/subsys/tracing/Kconfig
@@ -159,6 +159,13 @@ config TRACING_BACKEND_RAM
 	  be dumped to a file at runtime with a debugger.
 	  See gdb dump binary memory documentation for example.
 
+config TRACING_BACKEND_SEMIHOST
+	bool "Semihost backend"
+	depends on SEMIHOST
+	help
+	  Use semihosting to output tracing data. This is useful
+	  for debugging on a host machine, such as when using QEMU.
+
 config TRACING_BACKEND_ADSP_MEMORY_WINDOW
 	bool "Memory window in RAM"
 	depends on SOC_FAMILY_INTEL_ADSP
@@ -174,6 +181,7 @@ config TRACING_BACKEND_NAME
 	default "tracing_backend_usb" if TRACING_BACKEND_USB
 	default "tracing_backend_posix" if TRACING_BACKEND_POSIX
 	default "tracing_backend_ram" if TRACING_BACKEND_RAM
+	default "tracing_backend_semihost" if TRACING_BACKEND_SEMIHOST
 	default "tracing_backend_adsp_memory_window" if TRACING_BACKEND_ADSP_MEMORY_WINDOW
 
 config RAM_TRACING_BUFFER_SIZE