kernel/sched: fix logging after stack overflow

	- This commit changes logging method from
	  dbg to lldbg to print stack overflow information.
	  This is done because after stack overflow, using
	  dbg does not work because of more stack memory
	  requirement. But in the lldbg case, it uses
	  low level syslog, so it uses minimal stack memory.

os/kernel/sched/Make.defs

@@ -62,6 +62,10 @@ CSRCS += sched_lock.c sched_unlock.c sched_lockcount.c sched_self.c
 CSRCS += sched_getaffinity.c sched_setaffinity.c
 CSRCS += sched_getcpu.c
 
+ifeq ($(CONFIG_SW_STACK_OVERFLOW_DETECTION),y)
+CSRCS += sched_checkstackoverflow.c
+endif
+
 ifeq ($(CONFIG_PRIORITY_INHERITANCE),y)
 CSRCS += sched_reprioritize.c
 endif

os/kernel/sched/sched.h

@@ -358,6 +358,10 @@ void sched_addblocked(FAR struct tcb_s *btcb, tstate_t task_state);
 void sched_removeblocked(FAR struct tcb_s *btcb);
 int sched_setpriority(FAR struct tcb_s *tcb, int sched_priority);
 
+#ifdef CONFIG_SW_STACK_OVERFLOW_DETECTION
+void sched_checkstackoverflow(FAR struct tcb_s *rtcb);
+#endif
+
 #ifdef CONFIG_PRIORITY_INHERITANCE
 int sched_reprioritize(FAR struct tcb_s *tcb, int sched_priority);
 #else

os/kernel/sched/sched_addreadytorun.c

@@ -124,14 +124,7 @@ bool sched_addreadytorun(FAR struct tcb_s *btcb)
 	bool ret;
 
 #ifdef CONFIG_SW_STACK_OVERFLOW_DETECTION
-	if (*(uint32_t *)(rtcb->stack_base_ptr) != STACK_COLOR) {
-		dbg_noarg("###############    STACK OVERFLOW at pid %d ", rtcb->pid);
-#if CONFIG_TASK_NAME_SIZE > 0
-		dbg_noarg("(%s) ", rtcb->name);
-#endif
-		dbg_noarg("###################\n");
-		PANIC();
-	}
+	sched_checkstackoverflow(rtcb);
 #endif
 	/* Check if pre-emption is disabled for the current running task and if
 	 * the new ready-to-run task would cause the current running task to be
@@ -182,14 +175,7 @@ bool sched_addreadytorun(FAR struct tcb_s *btcb)
 	int cpu;
 
 #ifdef CONFIG_SW_STACK_OVERFLOW_DETECTION
-	if (*(uint32_t *)(rtcb->stack_base_ptr) != STACK_COLOR) {
-		dbg_noarg("###############    STACK OVERFLOW at pid %d ", rtcb->pid);
-#if CONFIG_TASK_NAME_SIZE > 0
-		dbg_noarg("(%s) ", rtcb->name);
-#endif
-		dbg_noarg("###################\n");
-		PANIC();
-	}
+	sched_checkstackoverflow(rtcb);
 #endif
 	/* Check if the blocked TCB is locked to this CPU */
 

os/kernel/sched/sched_checkstackoverflow.c

@@ -0,0 +1,83 @@
+/****************************************************************************
+ *
+ * Copyright 2025 Samsung Electronics All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific
+ * language governing permissions and limitations under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <tinyara/config.h>
+#include <tinyara/arch.h>
+#include <tinyara/sched.h>
+#include <tinyara/irq.h>
+
+#include <assert.h>
+#include <debug.h>
+#include <stdint.h>
+
+#include "sched/sched.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: sched_checkstackoverflow
+ *
+ * Description:
+ *   This function checks stack overflow condition for a thread.
+ *
+ * Inputs:
+ *   rtcb - Points to the TCB that is ready-to-run
+ *
+ ****************************************************************************/
+
+void sched_checkstackoverflow(FAR struct tcb_s *rtcb)
+{
+	irqstate_t flags = enter_critical_section();
+
+	if (*(uint32_t *)(rtcb->stack_base_ptr) != STACK_COLOR) {
+		lldbg_noarg("\n###############    STACK OVERFLOW at pid %d ", rtcb->pid);
+#if CONFIG_TASK_NAME_SIZE > 0
+		lldbg_noarg("(%s) ", rtcb->name);
+#endif
+		lldbg_noarg("###################\n");
+		PANIC();
+	}
+
+	leave_critical_section(flags);
+}

os/kernel/sched/sched_removereadytorun.c

@@ -116,15 +116,9 @@ bool sched_removereadytorun(FAR struct tcb_s *rtcb)
 	bool ret = false;
 
 #ifdef CONFIG_SW_STACK_OVERFLOW_DETECTION
-	if (*(uint32_t *)(rtcb->stack_base_ptr) != STACK_COLOR) {
-		dbg_noarg("###############    STACK OVERFLOW at pid %d ", rtcb->pid);
-#if CONFIG_TASK_NAME_SIZE > 0
-		dbg_noarg("(%s) ", rtcb->name);
-#endif
-		dbg_noarg("###################\n");
-		PANIC();
-	}
+	sched_checkstackoverflow(rtcb);
 #endif
+
 	/* Check if the TCB to be removed is at the head of the ready to run list.
 	 * In this case, we are removing the currently active task.
 	 */
@@ -157,15 +151,9 @@ bool sched_removereadytorun(FAR struct tcb_s *rtcb)
 	int cpu;
 
 #ifdef CONFIG_SW_STACK_OVERFLOW_DETECTION
-	if (*(uint32_t *)(rtcb->stack_base_ptr) != STACK_COLOR) {
-		dbg_noarg("###############    STACK OVERFLOW at pid %d ", rtcb->pid);
-#if CONFIG_TASK_NAME_SIZE > 0
-		dbg_noarg("(%s) ", rtcb->name);
-#endif
-		dbg_noarg("###################\n");
-		PANIC();
-	}
+	sched_checkstackoverflow(rtcb);
 #endif
+
 	/* Which CPU (if any) is the task running on? Which task list holds
 	 * the TCB
 	 */