* arch/arm/src/common/arm_backtrace_fp.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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 <nuttx/config.h>
#include <nuttx/arch.h>
#include "sched/sched.h"
#include "arm_internal.h"
* Pre-processor Definitions
****************************************************************************/
* Name: backtrace
*
* Description:
* backtrace() parsing the return address through frame pointer
*
* stack frame:
* +---------------------+ <- caller's SP
* | args r0, r1 | <- passed by register
* +---------------------+
* | saved lr (return) | <- push {r7, lr}
* | saved r7 (fp) |
* +---------------------+ <- r7 (frame pointer)
* | local var (r1) | <- sp-0
* | local var (r0) | <- sp-4
* +---------------------+ <- sp (sp-8)
*
****************************************************************************/
nosanitize_address
static int backtrace(uintptr_t *base, uintptr_t *limit,
uintptr_t *fp, uintptr_t *pc,
void **buffer, int size, int *skip)
{
int i = 0;
if (pc)
{
if ((*skip)-- <= 0)
{
buffer[i++] = (void *)((uintptr_t)pc & ~1);
}
}
* [fp + 1] = return address (caller's PC)
*/
for (; i < size; fp = (uintptr_t *)fp[0])
{
if (fp == NULL || fp > limit || fp < base || *fp == 0)
{
break;
}
if ((*skip)-- <= 0)
{
buffer[i++] = (void *)((fp[1] & ~1) - 2);
}
}
return i;
}
* Public Functions
****************************************************************************/
* Name: up_backtrace
*
* Description:
* up_backtrace() returns a backtrace for the TCB, in the array
* pointed to by buffer. A backtrace is the series of currently active
* function calls for the program. Each item in the array pointed to by
* buffer is of type void *, and is the return address from the
* corresponding stack frame. The size argument specifies the maximum
* number of addresses that can be stored in buffer. If the backtrace is
* larger than size, then the addresses corresponding to the size most
* recent function calls are returned; to obtain the complete backtrace,
* make sure that buffer and size are large enough.
*
* Input Parameters:
* tcb - Address of the task's TCB
* buffer - Return address from the corresponding stack frame
* size - Maximum number of addresses that can be stored in buffer
* skip - number of addresses to be skipped
*
* Returned Value:
* up_backtrace() returns the number of addresses returned in buffer
*
* Assumptions:
* Have to make sure tcb keep safe during function executing, it means
* 1. Tcb have to be self or not-running. In SMP case, the running task
* PC & SP cannot be backtrace, as whose get from tcb is not the newest.
* 2. Tcb have to keep not be freed. In task exiting case, have to
* make sure the tcb get from pid and up_backtrace in one critical
* section procedure.
*
****************************************************************************/
nosanitize_address
int up_backtrace(struct tcb_s *tcb,
void **buffer, int size, int skip)
{
struct tcb_s *rtcb = running_task();
int ret;
if (size <= 0 || !buffer)
{
return 0;
}
if (tcb == NULL || tcb == rtcb)
{
if (up_interrupt_context())
{
#if CONFIG_ARCH_INTERRUPTSTACK > 7
void *istackbase = (void *)up_get_intstackbase(this_cpu());
ret = backtrace(istackbase,
istackbase + INTSTACK_SIZE,
(void *)__builtin_frame_address(0),
NULL, buffer, size, &skip);
#else
ret = backtrace(rtcb->stack_base_ptr,
rtcb->stack_base_ptr + rtcb->adj_stack_size,
(void *)__builtin_frame_address(0),
NULL, buffer, size, &skip);
#endif
if (ret < size)
{
ret += backtrace(rtcb->stack_base_ptr,
rtcb->stack_base_ptr + rtcb->adj_stack_size,
(void *)((uint32_t *)running_regs())[REG_FP],
(void *)((uint32_t *)running_regs())[REG_PC],
&buffer[ret], size - ret, &skip);
}
}
else
{
ret = backtrace(rtcb->stack_base_ptr,
rtcb->stack_base_ptr + rtcb->adj_stack_size,
(void *)__builtin_frame_address(0),
NULL, buffer, size, &skip);
}
}
else
{
ret = backtrace(tcb->stack_base_ptr,
tcb->stack_base_ptr + tcb->adj_stack_size,
(void *)tcb->xcp.regs[REG_FP],
(void *)tcb->xcp.regs[REG_PC],
buffer, size, &skip);
}
return ret;
}