From 2ba85c1bc84ef4710e0701b0adfe18deeab4d5ce Mon Sep 17 00:00:00 2001
From: Kaspar Schleiser <kaspar@schleiser.de>
Date: Thu, 6 Aug 2020 13:24:06 +0200
Subject: [PATCH] core: add support for test_utils_print_stack_usage

- activate THREAD_CREATE_STACKTEST also if test_utils_print_stack_usage
  is used

- make thread_measure_stack_free() available unconditionally

- if DEVELHELP is active, call test_utils_print_stack_usage() on any
  thread exit

- if DEVELHELP is active, call test_utils_print_stack_usage() after main
  for the idle thread, if that is used
---
 core/include/thread.h |  2 --
 core/lib/init.c       | 13 ++++++++++---
 core/sched.c          |  6 ++++++
 core/thread.c         |  5 ++---
 4 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/core/include/thread.h b/core/include/thread.h
index 1a67398424..dd1ee69040 100644
--- a/core/include/thread.h
+++ b/core/include/thread.h
@@ -438,7 +438,6 @@ void thread_add_to_list(list_node_t *list, thread_t *thread);
  */
 const char *thread_getname(kernel_pid_t pid);
 
-#ifdef DEVELHELP
 /**
  * @brief Measures the stack usage of a stack
  *
@@ -449,7 +448,6 @@ const char *thread_getname(kernel_pid_t pid);
  * @return          the amount of unused space of the thread's stack
  */
 uintptr_t thread_measure_stack_free(const char *stack);
-#endif /* DEVELHELP */
 
 /**
  * @brief   Get the number of bytes used on the ISR stack
diff --git a/core/lib/init.c b/core/lib/init.c
index 0e651fb835..840677c49e 100644
--- a/core/lib/init.c
+++ b/core/lib/init.c
@@ -40,6 +40,9 @@
 
 extern int main(void);
 
+static char main_stack[THREAD_STACKSIZE_MAIN];
+static char idle_stack[THREAD_STACKSIZE_IDLE];
+
 static void *main_trampoline(void *arg)
 {
     (void)arg;
@@ -54,12 +57,16 @@ static void *main_trampoline(void *arg)
 
     main();
 
+#ifdef MODULE_TEST_UTILS_PRINT_STACK_USAGE
+    void print_stack_usage_metric(const char *name, void *stack, unsigned max_size);
+    if (IS_USED(MODULE_CORE_IDLE_THREAD)) {
+        print_stack_usage_metric("idle", idle_stack, THREAD_STACKSIZE_IDLE);
+    }
+#endif
+
     return NULL;
 }
 
-static char main_stack[THREAD_STACKSIZE_MAIN];
-static char idle_stack[THREAD_STACKSIZE_IDLE];
-
 static void *idle_thread(void *arg)
 {
     (void)arg;
diff --git a/core/sched.c b/core/sched.c
index 8ff2ec1d6d..fb8dbc3d7c 100644
--- a/core/sched.c
+++ b/core/sched.c
@@ -304,6 +304,12 @@ NORETURN void sched_task_exit(void)
     DEBUG("sched_task_exit: ending thread %" PRIkernel_pid "...\n",
           thread_getpid());
 
+#if defined(MODULE_TEST_UTILS_PRINT_STACK_USAGE) && defined(DEVELHELP)
+    void print_stack_usage_metric(const char *name, void *stack, unsigned max_size);
+    thread_t *me = thread_get_active();
+    print_stack_usage_metric(me->name, me->stack_start, me->stack_size);
+#endif
+
     (void)irq_disable();
     sched_threads[thread_getpid()] = NULL;
     sched_num_threads--;
diff --git a/core/thread.c b/core/thread.c
index ff3dcc7687..430130d761 100644
--- a/core/thread.c
+++ b/core/thread.c
@@ -171,7 +171,6 @@ void thread_add_to_list(list_node_t *list, thread_t *thread)
     list->next = new_node;
 }
 
-#ifdef DEVELHELP
 uintptr_t thread_measure_stack_free(const char *stack)
 {
     /* Alignment of stack has been fixed (if needed) by thread_create(), so
@@ -188,7 +187,6 @@ uintptr_t thread_measure_stack_free(const char *stack)
 
     return space_free;
 }
-#endif
 
 kernel_pid_t thread_create(char *stack, int stacksize, uint8_t priority,
                            int flags, thread_task_func_t function, void *arg,
@@ -234,7 +232,8 @@ kernel_pid_t thread_create(char *stack, int stacksize, uint8_t priority,
     _init_tls(thread->tls);
 #endif
 
-#if defined(DEVELHELP) || IS_ACTIVE(SCHED_TEST_STACK)
+#if defined(DEVELHELP) || defined(SCHED_TEST_STACK) \
+    || defined(MODULE_TEST_UTILS_PRINT_STACK_USAGE)
     if (flags & THREAD_CREATE_STACKTEST) {
         /* assign each int of the stack the value of it's address. Alignment
          * has been handled above, so silence -Wcast-align */