kernel / tools / perf / scripts / python / arm-cs-trace-disasm.py

# SPDX-License-Identifier: GPL-2.0
# arm-cs-trace-disasm.py: ARM CoreSight Trace Dump With Disassember
#
# Author: Tor Jeremiassen <[e-mail]>
#         Mathieu Poirier <[e-mail]>
#         Leo Yan <[e-mail]>
#         Al Grant <[e-mail]>

from __future__ import print_function
import os
from os import path
import sys
import re
from subprocess import *
from optparse import OptionParser, make_option

from perf_trace_context import perf_set_itrace_options, \
	perf_sample_insn, perf_sample_srccode

# Below are some example commands for using this script.
#
# Output disassembly with objdump:
#  perf script -s scripts/python/arm-cs-trace-disasm.py \
#		-- -d objdump -k path/to/vmlinux
# Output disassembly with llvm-objdump:
#  perf script -s scripts/python/arm-cs-trace-disasm.py \
#		-- -d llvm-objdump-11 -k path/to/vmlinux
# Output only source line and symbols:
#  perf script -s scripts/python/arm-cs-trace-disasm.py

# Command line parsing.
option_list = [
	# formatting options for the bottom entry of the stack
	make_option("-k", "--vmlinux", dest="vmlinux_name",
		    help="Set path to vmlinux file"),
	make_option("-d", "--objdump", dest="objdump_name",
		    help="Set path to objdump executable file"),
	make_option("-v", "--verbose", dest="verbose",
		    action="store_true", default=False,
		    help="Enable debugging log")
]

parser = OptionParser(option_list=option_list)
(options, args) = parser.parse_args()

# Initialize global dicts and regular expression
disasm_cache = dict()
cpu_data = dict()
disasm_re = re.compile("^\s*([0-9a-fA-F]+):")
disasm_func_re = re.compile("^\s*([0-9a-fA-F]+)\s.*:")
cache_size = 64*1024

glb_source_file_name	= None
glb_line_number		= None
glb_dso			= None

def get_optional(perf_dict, field):
       if field in perf_dict:
               return perf_dict[field]
       return "[unknown]"

def get_offset(perf_dict, field):
	if field in perf_dict:
		return f"+0x{perf_dict[field]:x}"
	return ""

def get_dso_file_path(dso_name, dso_build_id):
	if (dso_name == "[kernel.kallsyms]" or dso_name == "vmlinux"):
		if (options.vmlinux_name):
			return options.vmlinux_name;
		else:
			return dso_name

	if (dso_name == "[vdso]") :
		append = "/vdso"
	else:
		append = "/elf"

	dso_path = f"{os.environ['PERF_BUILDID_DIR']}/{dso_name}/{dso_build_id}{append}"
	# Replace duplicate slash chars to single slash char
	dso_path = dso_path.replace('//', '/', 1)
	return dso_path

def read_disam(dso_fname, dso_start, start_addr, stop_addr):
	addr_range = str(start_addr) + ":" + str(stop_addr) + ":" + dso_fname

	# Don't let the cache get too big, clear it when it hits max size
	if (len(disasm_cache) > cache_size):
		disasm_cache.clear();

	if addr_range in disasm_cache:
		disasm_output = disasm_cache[addr_range];
	else:
		start_addr = start_addr - dso_start;
		stop_addr = stop_addr - dso_start;
		disasm = [ options.objdump_name, "-d", "-z",
			   f"--start-address=0x{start_addr:x}",
			   f"--stop-address=0x{stop_addr:x}" ]
		disasm += [ dso_fname ]
		disasm_output = check_output(disasm).decode('utf-8').split('\n')
		disasm_cache[addr_range] = disasm_output

	return disasm_output

def print_disam(dso_fname, dso_start, start_addr, stop_addr):
	for line in read_disam(dso_fname, dso_start, start_addr, stop_addr):
		m = disasm_func_re.search(line)
		if m is None:
			m = disasm_re.search(line)
			if m is None:
				continue
		print(f"\t{line}")

def print_sample(sample):
	print(f"Sample = {{ cpu: {sample['cpu']:04} addr: 0x{sample['addr']:016x} " \
	      f"phys_addr: 0x{sample['phys_addr']:016x} ip: 0x{sample['ip']:016x} " \
	      f"pid: {sample['pid']} tid: {sample['tid']} period: {sample['period']} time: {sample['time']} }}")

def trace_begin():
	print('ARM CoreSight Trace Data Assembler Dump')

def trace_end():
	print('End')

def trace_unhandled(event_name, context, event_fields_dict):
	print(' '.join(['%s=%s'%(k,str(v))for k,v in sorted(event_fields_dict.items())]))

def common_start_str(comm, sample):
	sec = int(sample["time"] / 1000000000)
	ns = sample["time"] % 1000000000
	cpu = sample["cpu"]
	pid = sample["pid"]
	tid = sample["tid"]
	return f"{comm:>16} {pid:>5}/{tid:<5} [{cpu:04}] {sec:9}.{ns:09}  "

# This code is copied from intel-pt-events.py for printing source code
# line and symbols.
def print_srccode(comm, param_dict, sample, symbol, dso):
	ip = sample["ip"]
	if symbol == "[unknown]":
		start_str = common_start_str(comm, sample) + ("%x" % ip).rjust(16).ljust(40)
	else:
		offs = get_offset(param_dict, "symoff")
		start_str = common_start_str(comm, sample) + (symbol + offs).ljust(40)

	global glb_source_file_name
	global glb_line_number
	global glb_dso

	source_file_name, line_number, source_line = perf_sample_srccode(perf_script_context)
	if source_file_name:
		if glb_line_number == line_number and glb_source_file_name == source_file_name:
			src_str = ""
		else:
			if len(source_file_name) > 40:
				src_file = ("..." + source_file_name[-37:]) + " "
			else:
				src_file = source_file_name.ljust(41)

			if source_line is None:
				src_str = src_file + str(line_number).rjust(4) + " <source not found>"
			else:
				src_str = src_file + str(line_number).rjust(4) + " " + source_line
		glb_dso = None
	elif dso == glb_dso:
		src_str = ""
	else:
		src_str = dso
		glb_dso = dso

	glb_line_number = line_number
	glb_source_file_name = source_file_name

	print(f"{start_str}{src_str}")

def process_event(param_dict):
	global cache_size
	global options

	sample = param_dict["sample"]
	comm = param_dict["comm"]

	name = param_dict["ev_name"]
	dso = get_optional(param_dict, "dso")
	dso_bid = get_optional(param_dict, "dso_bid")
	dso_start = get_optional(param_dict, "dso_map_start")
	dso_end = get_optional(param_dict, "dso_map_end")
	symbol = get_optional(param_dict, "symbol")

	if (options.verbose == True):
		print(f"Event type: {name}")
		print_sample(sample)

	# If cannot find dso so cannot dump assembler, bail out
	if (dso == '[unknown]'):
		return

	# Validate dso start and end addresses
	if ((dso_start == '[unknown]') or (dso_end == '[unknown]')):
		print(f"Failed to find valid dso map for dso {dso}")
		return

	if (name[0:12] == "instructions"):
		print_srccode(comm, param_dict, sample, symbol, dso)
		return

	# Don't proceed if this event is not a branch sample, .
	if (name[0:8] != "branches"):
		return

	cpu = sample["cpu"]
	ip = sample["ip"]
	addr = sample["addr"]

	# Initialize CPU data if it's empty, and directly return back
	# if this is the first tracing event for this CPU.
	if (cpu_data.get(str(cpu) + 'addr') == None):
		cpu_data[str(cpu) + 'addr'] = addr
		return

	# The format for packet is:
	#
	#		  +------------+------------+------------+
	#  sample_prev:   |    addr    |    ip	    |	 cpu	 |
	#		  +------------+------------+------------+
	#  sample_next:   |    addr    |    ip	    |	 cpu	 |
	#		  +------------+------------+------------+
	#
	# We need to combine the two continuous packets to get the instruction
	# range for sample_prev::cpu:
	#
	#     [ sample_prev::addr .. sample_next::ip ]
	#
	# For this purose, sample_prev::addr is stored into cpu_data structure
	# and read back for 'start_addr' when the new packet comes, and we need
	# to use sample_next::ip to calculate 'stop_addr', plusing extra 4 for
	# 'stop_addr' is for the sake of objdump so the final assembler dump can
	# include last instruction for sample_next::ip.
	start_addr = cpu_data[str(cpu) + 'addr']
	stop_addr  = ip + 4

	# Record for previous sample packet
	cpu_data[str(cpu) + 'addr'] = addr

	# Handle CS_ETM_TRACE_ON packet if start_addr=0 and stop_addr=4
	if (start_addr == 0 and stop_addr == 4):
		print(f"CPU{cpu}: CS_ETM_TRACE_ON packet is inserted")
		return

	if (start_addr < int(dso_start) or start_addr > int(dso_end)):
		print(f"Start address 0x{start_addr:x} is out of range [ 0x{dso_start:x} .. 0x{dso_end:x} ] for dso {dso}")
		return

	if (stop_addr < int(dso_start) or stop_addr > int(dso_end)):
		print(f"Stop address 0x{stop_addr:x} is out of range [ 0x{dso_start:x} .. 0x{dso_end:x} ] for dso {dso}")
		return

	if (options.objdump_name != None):
		# It doesn't need to decrease virtual memory offset for disassembly
		# for kernel dso, so in this case we set vm_start to zero.
		if (dso == "[kernel.kallsyms]"):
			dso_vm_start = 0
		else:
			dso_vm_start = int(dso_start)

		dso_fname = get_dso_file_path(dso, dso_bid)
		if path.exists(dso_fname):
			print_disam(dso_fname, dso_vm_start, start_addr, stop_addr)
		else:
			print(f"Failed to find dso {dso} for address range [ 0x{start_addr:x} .. 0x{stop_addr:x} ]")

	print_srccode(comm, param_dict, sample, symbol, dso)