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/* -*- linux-c -*-
* Stack tracing functions
* Copyright (C) 2005-2008 Red Hat Inc.
* Copyright (C) 2005 Intel Corporation.
*
* This file is part of systemtap, and is free software. You can
* redistribute it and/or modify it under the terms of the GNU General
* Public License (GPL); either version 2, or (at your option) any
* later version.
*/
#ifndef _STACK_C_
#define _STACK_C_
/** @file stack.c
* @brief Stack Tracing Functions
*/
/** @addtogroup stack Stack Tracing Functions
*
* @{
*/
#include "sym.c"
#include "regs.h"
#include "unwind.c"
#define MAXBACKTRACE 20
#if defined (__x86_64__)
#include "stack-x86_64.c"
#elif defined (__ia64__)
#include "stack-ia64.c"
#elif defined (__i386__)
#include "stack-i386.c"
#elif defined (__powerpc64__)
#include "stack-ppc64.c"
#elif defined (__arm__)
#include "stack-arm.c"
#elif defined (__s390__) || defined (__s390x__)
#include "stack-s390.c"
#else
#error "Unsupported architecture"
#endif
/** Prints the stack backtrace
* @param regs A pointer to the struct pt_regs.
*/
static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
{
if (verbose) {
/* print the current address */
if (pi) {
_stp_print("Returning from: ");
_stp_symbol_print((unsigned long)_stp_probe_addr_r(pi));
_stp_print("\nReturning to : ");
_stp_symbol_print((unsigned long)_stp_ret_addr_r(pi));
} else {
_stp_print_char(' ');
_stp_symbol_print(REG_IP(regs));
}
_stp_print_char('\n');
} else if (pi)
_stp_printf("%p %p ", (int64_t)(long)_stp_ret_addr_r(pi), (int64_t) REG_IP(regs));
else
_stp_printf("%p ", (int64_t) REG_IP(regs));
__stp_stack_print(regs, verbose, levels);
}
/** Writes stack backtrace to a string
*
* @param str string
* @param regs A pointer to the struct pt_regs.
* @returns void
*/
static void _stp_stack_snprint(char *str, int size, struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
{
/* To get a string, we use a simple trick. First flush the print buffer, */
/* then call _stp_stack_print, then copy the result into the output string */
/* and clear the print buffer. */
_stp_pbuf *pb = per_cpu_ptr(Stp_pbuf, smp_processor_id());
_stp_print_flush();
_stp_stack_print(regs, verbose, pi, levels);
strlcpy(str, pb->buf, size < (int)pb->len ? size : (int)pb->len);
pb->len = 0;
}
/** Prints the user stack backtrace
* @param str string
* @returns Same string as was input with trace info appended,
* @note Currently limited to a depth of two. Works from jprobes and kprobes.
*/
#if 0
static void _stp_ustack_print(char *str)
{
struct pt_regs *nregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long)current->thread_info)) - 1;
_stp_printf("%p : [user]\n", (int64_t) REG_IP(nregs));
if (REG_SP(nregs))
_stp_printf("%p : [user]\n", (int64_t) (*(unsigned long *)REG_SP(nregs)));
}
#endif /* 0 */
/** @} */
#endif /* _STACK_C_ */
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