debug: thread monitor allow to access more thread information

The thread monitor allows to iterate over the thread context
structures for each existing thread (fiber/task) in the system.

Thread context structures do not expose thread entry information
directly. Although all the information can be scavenged from memory
stacks. Besides, accessing the information depends on the stack
implementation for each architecture.

By extending the tcs we allow a direct access to the thread
entry point and its parameters, only when thread monitor is
enabled.

It also allows a task to access its kernel task structure
through the first parameter of the thread.

This allows a debugger application to access the information directly
from the thread context structures list.

Change-Id: I0a435942b80eddffdf405016ac4056eb7aa1239c
Signed-off-by: Juan Manuel Cruz <juan.m.cruz.alcaraz@intel.com>

arch/arc/core/thread.c

@@ -143,6 +143,13 @@ void _new_thread(char *pStackMem, unsigned stackSize, _thread_entry_t pEntry,
 	tcs->custom_data = NULL;
 #endif
 
+#ifdef CONFIG_THREAD_MONITOR
+	/*
+	 * In debug mode tcs->entry give direct access to the thread entry
+	 * and the corresponding parameters.
+	 */
+	tcs->entry = (struct __thread_entry *)(pInitCtx);
+#endif
 	/*
 	 * intlock_key is constructed based on ARCv2 ISA Programmer's
 	 * Reference Manual CLRI instruction description:

arch/arc/include/nano_private.h

@@ -48,6 +48,16 @@ extern "C" {
 #endif
 
 #ifndef _ASMLANGUAGE
+
+#ifdef CONFIG_THREAD_MONITOR
+struct __thread_entry {
+	_thread_entry_t pEntry;
+	void *parameter1;
+	void *parameter2;
+	void *parameter3;
+};
+#endif /*CONFIG_THREAD_MONITOR*/
+
 struct coop {
 	/*
 	 * Saved on the stack as part of handling a regular IRQ or by the kernel
@@ -175,6 +185,7 @@ struct tcs {
 	struct coop coopReg;
 	struct preempt preempReg;
 #ifdef CONFIG_THREAD_MONITOR
+	struct __thread_entry *entry; /* thread entry and parameters description */
 	struct tcs *next_thread;  /* next item in list of ALL fiber+tasks */
 #endif
 #ifdef CONFIG_NANO_TIMEOUTS

arch/arm/core/thread.c

@@ -135,6 +135,14 @@ void _new_thread(char *pStackMem, unsigned stackSize, _thread_entry_t pEntry,
 	tcs->custom_data = NULL;
 #endif
 
+#ifdef CONFIG_THREAD_MONITOR
+	/*
+	 * In debug mode tcs->entry give direct access to the thread entry
+	 * and the corresponding parameters.
+	 */
+	tcs->entry = (struct __thread_entry *)(pInitCtx);
+#endif
+
 	tcs->preempReg.psp = (uint32_t)pInitCtx;
 	tcs->basepri = 0;
 

arch/arm/include/nano_private.h

@@ -45,6 +45,16 @@ extern "C" {
 #endif
 
 #ifndef _ASMLANGUAGE
+
+#ifdef CONFIG_THREAD_MONITOR
+struct __thread_entry {
+	_thread_entry_t pEntry;
+	void *parameter1;
+	void *parameter2;
+	void *parameter3;
+};
+#endif /*CONFIG_THREAD_MONITOR*/
+
 struct coop {
 	/*
 	 * Unused for Cortex-M, which automatically saves the neccesary
@@ -120,6 +130,7 @@ struct tcs {
 	struct coop coopReg;
 	struct preempt preempReg;
 #if defined(CONFIG_THREAD_MONITOR)
+	struct __thread_entry *entry; /* thread entry and parameters description */
 	struct tcs *next_thread; /* next item in list of ALL fiber+tasks */
 #endif
 #ifdef CONFIG_NANO_TIMEOUTS

arch/x86/core/i386_sysV_abi/thread.c

@@ -103,6 +103,14 @@ static void _new_thread_internal(char *pStackMem, unsigned stackSize,
 
 	pInitialCtx = (unsigned long *)STACK_ROUND_DOWN(pStackMem + stackSize);
 
+#ifdef CONFIG_THREAD_MONITOR
+	/*
+	 * In debug mode tcs->entry give direct access to the thread entry
+	 * and the corresponding parameters.
+	 */
+	tcs->entry = (struct __thread_entry *)(pInitialCtx -
+		sizeof(struct __thread_entry));
+#endif
 	/*
 	 * We subtract 11 here to account for the thread entry routine
 	 * parameters

arch/x86/include/nano_private.h

@@ -409,6 +409,15 @@
 extern "C" {
 #endif
 
+#ifdef CONFIG_THREAD_MONITOR
+struct __thread_entry {
+	_thread_entry_t pEntry;
+	void *parameter1;
+	void *parameter2;
+	void *parameter3;
+};
+#endif /*CONFIG_THREAD_MONITOR*/
+
 /*
  * The following structure defines the set of 'non-volatile' integer registers.
  * These registers must be preserved by a called C function.  These are the
@@ -639,6 +648,7 @@ struct tcs {
 	tPreempReg preempReg; /* volatile integer register storage */
 
 #if defined(CONFIG_THREAD_MONITOR)
+	struct __thread_entry *entry; /* thread entry and parameters description */
 	struct tcs *next_thread; /* next item in list of ALL fiber+tasks */
 #endif
 #ifdef CONFIG_GDB_INFO

kernel/microkernel/k_task.c

@@ -181,6 +181,7 @@ void _k_state_bit_set(struct k_task *task_ptr, uint32_t bits)
 static void start_task(struct k_task *X, void (*func)(void))
 {
 	unsigned int task_options;
+	void *parameter1;
 
 	/* Note: the field X->worksize now represents the task size in bytes */
 
@@ -196,10 +197,16 @@ static void start_task(struct k_task *X, void (*func)(void))
 	 * the thread is a task, rather than a fiber.
 	 */
 
+#ifdef CONFIG_THREAD_MONITOR
+	parameter1 = (void *)X;
+#else
+	parameter1 = (void *)0;
+#endif
+
 	_new_thread((char *)X->workspace, /* pStackMem */
 			X->worksize,		/* stackSize */
 			(_thread_entry_t)func,  /* pEntry */
-			(void *)0,		/* parameter1 */
+			parameter1,		/* parameter1 */
 			(void *)0,		/* parameter2 */
 			(void *)0,		/* parameter3 */
 			-1,			/* priority */