coredump: Add test for threads core dump config

Add z_test which uses new configs to capture multiple
threads in a core dump and with all of the context
necessary to debug the threads.

Signed-off-by: Mark Holden <mholden@meta.com>

subsys/debug/coredump/Kconfig

@@ -60,6 +60,7 @@ config DEBUG_COREDUMP_MEMORY_DUMP_MIN
 
 config DEBUG_COREDUMP_MEMORY_DUMP_THREADS
 	bool "Threads"
+	depends on !SMP
 	select THREAD_STACK_INFO
 	select DEBUG_THREAD_INFO
 	select DEBUG_COREDUMP_THREADS_METADATA
@@ -98,6 +99,7 @@ config DEBUG_COREDUMP_SHELL
 
 config DEBUG_COREDUMP_THREADS_METADATA
 	bool "Threads metadata"
+	depends on !SMP
 	select DEBUG_THREAD_INFO
 	help
 	  Core dump will contain the threads metadata section containing

subsys/debug/coredump/coredump_core.c

@@ -58,6 +58,8 @@ static void dump_header(unsigned int reason)
 	backend_api->buffer_output((uint8_t *)&hdr, sizeof(hdr));
 }
 
+#if defined(CONFIG_DEBUG_COREDUMP_MEMORY_DUMP_MIN) || \
+	defined(CONFIG_DEBUG_COREDUMP_MEMORY_DUMP_THREADS)
 static void dump_thread(struct k_thread *thread)
 {
 	uintptr_t end_addr;
@@ -80,6 +82,7 @@ static void dump_thread(struct k_thread *thread)
 
 	coredump_memory_dump(thread->stack_info.start, end_addr);
 }
+#endif
 
 #if defined(CONFIG_COREDUMP_DEVICE)
 static void process_coredump_dev_memory(const struct device *dev)

tests/subsys/debug/coredump_threads/CMakeLists.txt

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(debug_coredump_threads)
+
+target_sources(app PRIVATE src/main.c)

tests/subsys/debug/coredump_threads/prj.conf

@@ -0,0 +1,7 @@
+# Copyright Meta Platforms, Inc. and its affiliates.
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_ZTEST=y
+
+CONFIG_DEBUG_COREDUMP=y
+CONFIG_DEBUG_COREDUMP_MEMORY_DUMP_THREADS=y

tests/subsys/debug/coredump_threads/src/main.c

@@ -0,0 +1,73 @@
+/*
+ * Copyright Meta Platforms, Inc. and its affiliates.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <stdio.h>
+#include <zephyr/kernel.h>
+#include <zephyr/ztest.h>
+
+#define STACK_SIZE 256
+#define THREAD_COUNT 7
+
+static struct k_thread threads[THREAD_COUNT];
+static uint32_t params[THREAD_COUNT];
+static K_THREAD_STACK_ARRAY_DEFINE(thread_stacks, THREAD_COUNT, STACK_SIZE);
+static K_SEM_DEFINE(sem, 0, 1);
+
+static void func0(uint32_t param)
+{
+	int ret = -EAGAIN;
+
+	while (ret != 0) {
+		ret = k_sem_take(&sem, K_NO_WAIT);
+		k_sleep(K_MSEC(param));
+	}
+
+	k_panic();
+}
+
+static void test_thread_entry(void *p1, void *p2, void *p3)
+{
+	uint32_t *param = (uint32_t *)p1;
+
+	func0(*param);
+}
+
+static void *coredump_threads_suite_setup(void)
+{
+	/* Spawn a few threads */
+	for (int i = 0; i < THREAD_COUNT; i++) {
+		params[i] = i;
+		k_thread_create(
+			&threads[i],
+			thread_stacks[i],
+			K_THREAD_STACK_SIZEOF(thread_stacks[i]),
+			test_thread_entry,
+			&params[i],
+			NULL,
+			NULL,
+			(THREAD_COUNT - i), /* arbitrary priority */
+			0,
+			K_NO_WAIT);
+
+		char thread_name[32];
+
+		snprintf(thread_name, sizeof(thread_name), "thread%d", i);
+		k_thread_name_set(&threads[i], thread_name);
+	}
+
+	return NULL;
+}
+
+ZTEST_SUITE(coredump_threads, NULL, coredump_threads_suite_setup, NULL, NULL, NULL);
+
+ZTEST(coredump_threads, test_crash)
+{
+	/* Give semaphore allowing one of the waiting threads to continue and panic */
+	k_sem_give(&sem);
+	for (int i = 0; i < THREAD_COUNT; i++) {
+		k_thread_join(&threads[i], K_FOREVER);
+	}
+}

tests/subsys/debug/coredump_threads/testcase.yaml

@@ -0,0 +1,34 @@
+# Copyright Meta Platforms, Inc. and its affiliates.
+# SPDX-License-Identifier: Apache-2.0
+
+common:
+  tags:
+    - coredump
+  ignore_faults: true
+  ignore_qemu_crash: true
+  integration_platforms:
+    - qemu_cortex_m3
+tests:
+  debug.coredump.threads:
+    filter: CONFIG_DEBUG_COREDUMP_MEMORY_DUMP_THREADS
+    harness: console
+    harness_config:
+      type: multi_line
+      # Verify core dump contains threads metadata section and several
+      # memory sections, two for each thread
+      regex:
+        - "E: #CD:BEGIN#"
+        - "E: #CD:5([aA])45([0-9a-fA-F]+)"
+        - "E: #CD:41([0-9a-fA-F]+)"
+        - "E: #CD:54([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:4([dD])([0-9a-fA-F]+)"
+        - "E: #CD:END#"