stack.c

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#ifndef _STACK_C_ /* -*- linux-c -*- */
#define _STACK_C_


/** @file stack.c
 * @brief Stack Tracing Functions
 */

/** @addtogroup stack Stack Tracing Functions
 * @{
 */

#include "sym.c"

static int (*_stp_kta)(unsigned long addr)=(void *)KTA;

#ifdef __x86_64__
static void __stp_stack_print (unsigned long *stack, int verbose, int levels)
{
        unsigned long addr;

        if (verbose)
                _stp_printf ("trace for %d (%s)\n", current->pid, current->comm);

        while (((long) stack & (THREAD_SIZE-1)) != 0) {
                addr = *stack++;
                if (_stp_kta(addr)) {
                        if (verbose) {
                                _stp_symbol_print (addr);
                                _stp_print ("\n");
                        } else
                                _stp_printf ("0x%lx ", addr);
                }
        }
        _stp_print_flush();
}


static void __stp_stack_sprint (String str, unsigned long *stack, int verbose, int levels)
{
        unsigned long addr;
        while (((long) stack & (THREAD_SIZE-1)) != 0) {
                addr = *stack++;
                if (_stp_kta(addr)) {
                        if (verbose)
                                _stp_symbol_sprint (str, addr);
                        else
                                _stp_sprintf (str, "0x%lx ", addr);
                }
        }
}

#else  /* i386 */

static inline int valid_stack_ptr (struct thread_info *tinfo, void *p)
{
        return  p > (void *)tinfo &&
                p < (void *)tinfo + THREAD_SIZE - 3;
}

static inline unsigned long _stp_print_context_stack (
        struct thread_info *tinfo,
        unsigned long *stack, 
        unsigned long ebp )
{
        unsigned long addr;

#ifdef  CONFIG_FRAME_POINTER
        while (valid_stack_ptr(tinfo, (void *)ebp)) {
                addr = *(unsigned long *)(ebp + 4);
                _stp_symbol_print (addr);
                _stp_print_cstr("\n");
                ebp = *(unsigned long *)ebp;
        }
#else
        while (valid_stack_ptr(tinfo, stack)) {
                addr = *stack++;
                if (_stp_kta (addr)) {
                        _stp_symbol_print (addr);
                        _stp_print_cstr ("\n");
                }
        }
#endif
        _stp_print_flush();
        return ebp;
}

static inline unsigned long _stp_sprint_context_stack (
        String str,
        struct thread_info *tinfo,
        unsigned long *stack, 
        unsigned long ebp )
{
        unsigned long addr;

#ifdef  CONFIG_FRAME_POINTER
        while (valid_stack_ptr(tinfo, (void *)ebp)) {
                addr = *(unsigned long *)(ebp + 4);
                _stp_symbol_sprint (str, addr);
                _stp_string_cat ("\n");
                ebp = *(unsigned long *)ebp;
        }
#else
        while (valid_stack_ptr(tinfo, stack)) {
                addr = *stack++;
                if (_stp_kta (addr)) {
                        _stp_symbol_sprint (addr);
                        _stp_string_cat ("\n");
                }
        }
#endif
        return ebp;
}

static void __stp_stack_print (unsigned long *stack, int verbose, int levels)
{
        unsigned long ebp;

        /* Grab ebp right from our regs */
        asm ("movl %%ebp, %0" : "=r" (ebp) : );

        while (stack) {
                struct thread_info *context = (struct thread_info *)
                        ((unsigned long)stack & (~(THREAD_SIZE - 1)));
                ebp = _stp_print_context_stack (context, stack, ebp);
                stack = (unsigned long*)context->previous_esp;
        }
}

static void __stp_stack_sprint (String str, unsigned long *stack, int verbose, int levels)
{
        unsigned long ebp;

        /* Grab ebp right from our regs */
        asm ("movl %%ebp, %0" : "=r" (ebp) : );

        while (stack) {
                struct thread_info *context = (struct thread_info *)
                        ((unsigned long)stack & (~(THREAD_SIZE - 1)));
                ebp = _stp_sprint_context_stack (str, context, stack, ebp);
                stack = (unsigned long*)context->previous_esp;
        }
}

#endif /* i386 */

/** Print stack dump.
 * Prints a stack dump to the print buffer.
 * @param verbose Verbosity
 * @param levels Number of levels to trace.
 * @todo Implement verbosity and levels parameters.
 * @bug levels parameter is not functional
 */

void _stp_stack_print (int verbose, int levels)
{
  unsigned long stack;
  __stp_stack_print (&stack, verbose, levels);
}

/** Writes stack dump to a String
 *
 * @param str String
 * @param verbose Verbosity
 * @param levels Number of levels to trace.
 * @returns Same String as was input.
 * @todo Implement verbosity and levels parameters.
 * @bug levels parameter is not functional
 */

String _stp_stack_sprint (String str, int verbose, int levels)
{
  unsigned long stack;
  __stp_stack_sprint (str, &stack, verbose, levels);
  _stp_log ("sss: str=%s\n", str->buf);
  return str;
}

/** @} */
#endif /* _STACK_C_ */