![Chris Metcalf](/assets/img/avatar_default.png)
This change is the result of some work to make the backtrace code more shareable between kernel, libc, and gdb. For the kernel, some good effects are to eliminate the hacky "VirtualAddress" typedef in favor of "unsigned long", to eliminate a bunch of spurious kernel doc comments, to remove the dead "bt_read_memory" function, and to use "__tilegx__" in #ifdefs instead of "TILE_CHIP". Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
163 lines
4 KiB
C
163 lines
4 KiB
C
/*
|
|
* Copyright 2010 Tilera Corporation. All Rights Reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation, version 2.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
|
|
* NON INFRINGEMENT. See the GNU General Public License for
|
|
* more details.
|
|
*/
|
|
|
|
#ifndef _ASM_TILE_BACKTRACE_H
|
|
#define _ASM_TILE_BACKTRACE_H
|
|
|
|
#include <linux/types.h>
|
|
|
|
/* Reads 'size' bytes from 'address' and writes the data to 'result'.
|
|
* Returns true if successful, else false (e.g. memory not readable).
|
|
*/
|
|
typedef bool (*BacktraceMemoryReader)(void *result,
|
|
unsigned long address,
|
|
unsigned int size,
|
|
void *extra);
|
|
|
|
typedef struct {
|
|
/* Current PC. */
|
|
unsigned long pc;
|
|
|
|
/* Current stack pointer value. */
|
|
unsigned long sp;
|
|
|
|
/* Current frame pointer value (i.e. caller's stack pointer) */
|
|
unsigned long fp;
|
|
|
|
/* Internal use only: caller's PC for first frame. */
|
|
unsigned long initial_frame_caller_pc;
|
|
|
|
/* Internal use only: callback to read memory. */
|
|
BacktraceMemoryReader read_memory_func;
|
|
|
|
/* Internal use only: arbitrary argument to read_memory_func. */
|
|
void *read_memory_func_extra;
|
|
|
|
} BacktraceIterator;
|
|
|
|
|
|
typedef enum {
|
|
|
|
/* We have no idea what the caller's pc is. */
|
|
PC_LOC_UNKNOWN,
|
|
|
|
/* The caller's pc is currently in lr. */
|
|
PC_LOC_IN_LR,
|
|
|
|
/* The caller's pc can be found by dereferencing the caller's sp. */
|
|
PC_LOC_ON_STACK
|
|
|
|
} CallerPCLocation;
|
|
|
|
|
|
typedef enum {
|
|
|
|
/* We have no idea what the caller's sp is. */
|
|
SP_LOC_UNKNOWN,
|
|
|
|
/* The caller's sp is currently in r52. */
|
|
SP_LOC_IN_R52,
|
|
|
|
/* The caller's sp can be found by adding a certain constant
|
|
* to the current value of sp.
|
|
*/
|
|
SP_LOC_OFFSET
|
|
|
|
} CallerSPLocation;
|
|
|
|
|
|
/* Bit values ORed into CALLER_* values for info ops. */
|
|
enum {
|
|
/* Setting the low bit on any of these values means the info op
|
|
* applies only to one bundle ago.
|
|
*/
|
|
ONE_BUNDLE_AGO_FLAG = 1,
|
|
|
|
/* Setting this bit on a CALLER_SP_* value means the PC is in LR.
|
|
* If not set, PC is on the stack.
|
|
*/
|
|
PC_IN_LR_FLAG = 2,
|
|
|
|
/* This many of the low bits of a CALLER_SP_* value are for the
|
|
* flag bits above.
|
|
*/
|
|
NUM_INFO_OP_FLAGS = 2,
|
|
|
|
/* We cannot have one in the memory pipe so this is the maximum. */
|
|
MAX_INFO_OPS_PER_BUNDLE = 2
|
|
};
|
|
|
|
|
|
/* Internal constants used to define 'info' operands. */
|
|
enum {
|
|
/* 0 and 1 are reserved, as are all negative numbers. */
|
|
|
|
CALLER_UNKNOWN_BASE = 2,
|
|
|
|
CALLER_SP_IN_R52_BASE = 4,
|
|
|
|
CALLER_SP_OFFSET_BASE = 8,
|
|
};
|
|
|
|
|
|
/* Current backtracer state describing where it thinks the caller is. */
|
|
typedef struct {
|
|
/*
|
|
* Public fields
|
|
*/
|
|
|
|
/* How do we find the caller's PC? */
|
|
CallerPCLocation pc_location : 8;
|
|
|
|
/* How do we find the caller's SP? */
|
|
CallerSPLocation sp_location : 8;
|
|
|
|
/* If sp_location == SP_LOC_OFFSET, then caller_sp == sp +
|
|
* loc->sp_offset. Else this field is undefined.
|
|
*/
|
|
uint16_t sp_offset;
|
|
|
|
/* In the most recently visited bundle a terminating bundle? */
|
|
bool at_terminating_bundle;
|
|
|
|
/*
|
|
* Private fields
|
|
*/
|
|
|
|
/* Will the forward scanner see someone clobbering sp
|
|
* (i.e. changing it with something other than addi sp, sp, N?)
|
|
*/
|
|
bool sp_clobber_follows;
|
|
|
|
/* Operand to next "visible" info op (no more than one bundle past
|
|
* the next terminating bundle), or -32768 if none.
|
|
*/
|
|
int16_t next_info_operand;
|
|
|
|
/* Is the info of in next_info_op in the very next bundle? */
|
|
bool is_next_info_operand_adjacent;
|
|
|
|
} CallerLocation;
|
|
|
|
extern void backtrace_init(BacktraceIterator *state,
|
|
BacktraceMemoryReader read_memory_func,
|
|
void *read_memory_func_extra,
|
|
unsigned long pc, unsigned long lr,
|
|
unsigned long sp, unsigned long r52);
|
|
|
|
|
|
extern bool backtrace_next(BacktraceIterator *state);
|
|
|
|
#endif /* _ASM_TILE_BACKTRACE_H */
|