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source: tools/gdb/utils-gdb.py @ a51dc0d

Last change on this file since a51dc0d was 262d4d51, checked in by Thierry Delisle <tdelisle@…>, 2 years ago
Updating gdb tools to latest invoke.h changes
Property mode set to `100644`
File size: 19.2 KB

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1	#
2	# Copyright (C) Lynn Tran, Jiachen Zhang 2018
3	#
4	# utils-gdb.py --
5	#
6	# Author : Lynn Tran
7	# Created On : Mon Oct 1 22:06:09 2018
8	# Last Modified By : Peter A. Buhr
9	# Last Modified On : Sat Jan 19 14:16:10 2019
10	# Update Count : 11
11	#
12
13	"""
14	To run this extension, the python name has to be as same as one of the loaded library
15	Additionally, the file must exist in a folder which is in gdb's safe path
16	"""
17	import collections
18	import gdb
19	import re
20
21	# set these signal handlers with some settings (nostop, noprint, pass)
22	gdb.execute('handle SIGALRM nostop noprint pass')
23	gdb.execute('handle SIGUSR1 nostop noprint pass')
24
25	CfaTypes = collections.namedtuple('CfaTypes', 'cluster_ptr processor_ptr thread_ptr int_ptr uintptr thread_state yield_state')
26
27	class ThreadInfo:
28	tid = 0
29	cluster = None
30	value = None
31
32	def __init__(self, cluster, value):
33	self.cluster = cluster
34	self.value = value
35
36	def is_system(self):
37	return False
38
39	# A named tuple representing information about a stack
40	StackInfo = collections.namedtuple('StackInfo', 'sp fp pc')
41
42	# A global variable to keep track of stack information as one switches from one
43	# task to another task
44	STACK = []
45
46	not_supported_error_msg = "Not a supported command for this language"
47
48	def is_cforall():
49	return True
50
51	def get_cfa_types():
52	# GDB types for various structures/types in CFA
53	return CfaTypes(cluster_ptr = gdb.lookup_type('struct cluster').pointer(),
54	processor_ptr = gdb.lookup_type('struct processor').pointer(),
55	thread_ptr = gdb.lookup_type('struct thread$').pointer(),
56	int_ptr = gdb.lookup_type('int').pointer(),
57	uintptr = gdb.lookup_type('uintptr_t'),
58	thread_state = gdb.lookup_type('enum __Coroutine_State'),
59	yield_state = gdb.lookup_type('enum __Preemption_Reason'))
60
61	def get_addr(addr):
62	"""
63	NOTE: sketchy solution to retrieve address. There is a better solution...
64	@addr: str of an address that can be in a format 0xfffff <type of the object
65	at this address>
66	Return: str of just the address
67	"""
68	str_addr = str(addr)
69	ending_addr_index = str_addr.find('<')
70	if ending_addr_index == -1:
71	return str(addr)
72	return str_addr[:ending_addr_index].strip()
73
74	def print_usage(obj):
75	print(obj.__doc__)
76
77	def parse(args):
78	"""
79	Split the argument list in string format, where each argument is separated
80	by whitespace delimiter, to a list of arguments like argv
81	@args: str of arguments
82	Return:
83	[] if args is an empty string
84	list if args is not empty
85	"""
86	# parse the string format of arguments and return a list of arguments
87	argv = args.split(' ')
88	if len(argv) == 1 and argv[0] == '':
89	return []
90	return argv
91
92	def single_field(obj):
93	"""
94	If the struct only has one field return it, otherwise error
95	"""
96
97	_type = obj.type
98	if len(_type.fields()) != 1:
99	return None
100
101	return obj[_type.fields()[0].name]
102
103
104	def start_from_dlist(dlist):
105	fs = dlist.type.fields()
106	if len(fs) != 1:
107	print("Error, can't understand dlist type for", dlist, dlist.name, dlist.type)
108	return None
109
110	return dlist[fs[0]]
111
112	def fix_dlink(ptr):
113	"""
114	Remove the higher order bit from the pointer
115	"""
116	ptype = ptr.type
117	size = ptype.sizeof
118	if size == 8:
119	bit = 1 << ((size*8)-1)
120	mask = bit - 1
121	elif size == 4:
122	bit = 0
123	mask = 1
124	else:
125	print("Unexpected pointer size while fixing dlink", size)
126
127	cfa_t = get_cfa_types()
128	uptr = ptr.cast(cfa_t.uintptr)
129	return ptr if 0 == uptr & mask else gdb.Value(b'\x00'*size, ptype)
130
131	class ClusterIter:
132	def __init__(self, root):
133	self.curr = None
134	self.root = root
135
136	def __iter__(self):
137	return self
138
139	def __next__(self):
140	# Clusters form a cycle
141	# If we haven't seen the root yet, then the root is the first
142	if not self.curr:
143	self.curr = self.root
144	return self.curr
145
146	# if we already saw the root, then go forward
147	self.curr = self.curr['_X4nodeS26__cluster____dbg_node_cltr_1']['_X4nextPS7cluster_1']
148
149	# if we reached the root again, then we are done
150	if self.curr == self.root:
151	raise StopIteration
152
153	# otherwise return the next
154	return self.curr
155
156	def all_clusters():
157	"""
158	Return: a list of all the clusters as an iterator.
159	obtained from gdb.Value of globalClusters.root (is an address)
160	"""
161	if not is_cforall():
162	return []
163
164	cluster_root = gdb.parse_and_eval('_X11mainClusterPS7cluster_1')
165	if cluster_root.address == 0x0:
166	print('No clusters, program terminated')
167	return []
168
169	return ClusterIter(cluster_root)
170
171	class ProcIter:
172	def __init__(self, root):
173	self.curr = None
174	self.root = root
175
176	def __iter__(self):
177	return self
178
179	def check(self):
180	# check if this is the last value
181	if not fix_dlink(self.curr):
182	raise StopIteration
183
184	def __next__(self):
185	cfa_t = get_cfa_types()
186
187	# Processors form a cycle
188	# If we haven't seen the root yet, then the root is the first
189	if not self.curr:
190	my_next = self.root
191	self.curr = my_next.cast(cfa_t.processor_ptr)
192
193	#check if this is an empty list
194	self.check()
195
196	return self.curr
197
198	# if we already saw the root, then go forward
199	my_next = self.curr['_X4linkS5dlink_S9processor__1']['_X4nextPY13__tE_generic__1']
200	self.curr = my_next.cast(cfa_t.processor_ptr)
201
202	#check if we reached the end
203	self.check()
204
205	# otherwise return the next
206	return self.curr
207
208	def proc_list(cluster):
209	"""
210	Return: for a given processor, return the active and idle processors, as 2 iterators
211	"""
212	cfa_t = get_cfa_types()
213	proclist = cluster['_X5procsS19__cluster_proc_list_1']
214
215	idle = start_from_dlist(proclist['_X5idlesS5dlist_S9processorS5dlink_S9processor___1'])['_X4nextPY13__tE_generic__1']
216	active = start_from_dlist(proclist['_X7activesS5dlist_S9processorS5dlink_S9processor___1'])['_X4nextPY13__tE_generic__1']
217	return ProcIter(active.cast(cfa_t.processor_ptr)), ProcIter(idle.cast(cfa_t.processor_ptr))
218
219	def all_processors():
220	procs = []
221	for c in all_clusters():
222	active, idle = proc_list(c)
223	for p in active:
224	procs.append(p)
225
226	for p in idle:
227	procs.append(p)
228
229	print(procs)
230	return procs
231
232	def tls_for_pthread(pthrd):
233	prev = gdb.selected_thread()
234	inf = gdb.selected_inferior()
235
236	thrd = inf.thread_from_thread_handle( pthrd )
237	thrd.switch()
238	tls = gdb.parse_and_eval('&_X9kernelTLSS16KernelThreadData_1')
239
240	prev.switch()
241	return tls
242
243	def tls_for_proc(proc):
244	return proc['_X10local_dataPS16KernelThreadData_1']
245
246	def thread_for_pthread(pthrd):
247	return tls_for_pthread(pthrd)['_X11this_threadVPS7thread$_1']
248
249	def thread_for_proc(proc):
250	return tls_for_proc(proc)['_X11this_threadVPS7thread$_1']
251
252
253
254	def find_curr_thread():
255	# btstr = gdb.execute('bt', to_string = True).splitlines()
256	# if len(btstr) == 0:
257	# print('error')
258	# return None
259	# return btstr[0].split('this=',1)[1].split(',')[0].split(')')[0]
260	return None
261
262	def lookup_cluster(name = None):
263	"""
264	Look up one or more cluster given a name
265	@name: str
266	Return: gdb.Value
267	"""
268	if not is_cforall():
269	return None
270
271	clusters = all_clusters()
272	if not clusters:
273	return None
274
275	if not name:
276	return clusters.root
277
278	# lookup for the task associated with the id
279	found = [c for c in clusters if c['_X4namePKc_1'].string() == name]
280
281	if not found:
282	print("Cannot find a cluster with the name: {}.".format(name))
283	return None
284
285	return found
286
287
288	def lookup_threads_by_cluster(cluster):
289	# Iterate through a circular linked list of threads and accumulate them in an array
290	threads = []
291
292	cfa_t = get_cfa_types()
293	head = single_field(cluster['_X7threadsS5dlist_S7thread$S18__thread_user_link__1'])
294	root = head['_X4nextPY13__tE_generic__1'].cast(cfa_t.thread_ptr)
295
296	if root == 0x0 or root.address == 0x0:
297	print('There are no tasks for cluster: {}'.format(cluster))
298	return threads
299
300	curr = root
301	tid = 0
302	sid = -1
303
304	while True:
305	t = ThreadInfo(cluster, curr)
306	if t.is_system():
307	t.tid = sid
308	sid -= 1
309	else:
310	t.tid = tid
311	tid += 1
312
313	threads.append(t)
314
315	curr = fix_dlink(single_field(curr['cltr_link'])['_X4nextPY13__tE_generic__1']).cast(cfa_t.thread_ptr)
316	if curr == root or curr == 0x0:
317	break
318
319	return threads
320
321	def system_thread(thread):
322	return False
323
324	def adjust_stack(pc, fp, sp):
325	# pop sp, fp, pc from global stack
326	gdb.execute('set $pc = {}'.format(pc))
327	gdb.execute('set $rbp = {}'.format(fp))
328	gdb.execute('set $sp = {}'.format(sp))
329
330	############################ COMMAND IMPLEMENTATION #########################
331
332	class Clusters(gdb.Command):
333	"""Cforall: Display currently known clusters
334	Usage:
335	info clusters : print out all the clusters
336	"""
337
338	def __init__(self):
339	super(Clusters, self).__init__('info clusters', gdb.COMMAND_USER)
340
341	def print_cluster(self, cluster_name, cluster_address):
342	print('{:>20} {:>20}'.format(cluster_name, cluster_address))
343
344	#entry point from gdb
345	def invoke(self, arg, from_tty):
346	if not is_cforall():
347	return
348
349	if arg:
350	print("info clusters does not take arguments")
351	print_usage(self)
352	return
353
354	self.print_cluster('Name', 'Address')
355
356	for c in all_clusters():
357	self.print_cluster(c['_X4namePKc_1'].string(), str(c))
358
359	print("")
360
361	############
362	class Processors(gdb.Command):
363	"""Cforall: Display currently known processors
364	Usage:
365	info processors : print out all the processors
366	info processors <cluster_name> : print out all processors in a given cluster
367	"""
368
369	def __init__(self):
370	super(Processors, self).__init__('info processors', gdb.COMMAND_USER)
371
372	def print_processor(self, processor, in_stats):
373	should_stop = processor['_X12do_terminateVb_1']
374	if not should_stop:
375	status = in_stats
376	else:
377	stop_count = processor['_X10terminatedS9semaphore_1']['_X5counti_1']
378	status_str = 'Last Thread' if stop_count >= 0 else 'Terminating'
379	status = '{}({},{})'.format(status_str, should_stop, stop_count)
380
381	print('{:>20} {:>11} {:<7} {:<}'.format(
382	processor['_X4namePKc_1'].string(),
383	status,
384	str(processor['_X18pending_preemptionb_1']),
385	str(processor)
386	))
387	tls = tls_for_proc( processor )
388	thrd = thread_for_proc( processor )
389	if thrd != 0x0:
390	tname = '{} {}'.format(thrd['self_cor']['name'].string(), str(thrd))
391	else:
392	tname = None
393
394	print('{:>20} {}'.format('Thread', tname))
395	print('{:>20} {}'.format('TLS', tls))
396
397	#entry point from gdb
398	def invoke(self, arg, from_tty):
399	if not is_cforall():
400	return
401
402	if not arg:
403	clusters = all_clusters()
404	else:
405	clusters = [lookup_cluster(arg)]
406
407	if not clusters:
408	print("No Cluster matching arguments found")
409	return
410
411	print('{:>20} {:>11} {:<7} {}'.format('Processor', '', 'Pending', 'Object'))
412	print('{:>20} {:>11} {:<7} {}'.format('Name', 'Status', 'Yield', 'Address'))
413	for c in clusters:
414	print('Cluster {}'.format(c['_X4namePKc_1'].string()))
415
416	active, idle = proc_list(c)
417	# print the processor information
418	for p in active:
419	self.print_processor(p, 'Active')
420
421	for p in idle:
422	self.print_processor(p, 'Idle')
423
424	print()
425
426	print()
427
428	############
429	class Threads(gdb.Command):
430	"""Cforall: Display currently known threads
431	Usage:
432	cfathreads : print Main Cluster threads, application threads only
433	cfathreads all : print all clusters, all threads
434	cfathreads <clusterName> : print cluster threads, application threads only
435	"""
436	def __init__(self):
437	# The first parameter of the line below is the name of the command. You
438	# can call it 'uc++ task'
439	super(Threads, self).__init__('info cfathreads', gdb.COMMAND_USER)
440
441	def print_formatted(self, marked, tid, name, state, address):
442	# print(marked, tid, name, state, address)
443	print('{:>1} {:>4} {:>20} {:>10} {:>20}'.format('*' if marked else ' ', tid, name, state, address))
444
445	def print_thread(self, thread, tid, marked):
446	# print("print", thread, tid, marked)
447	cfa_t = get_cfa_types()
448	ys = str(thread['preempted'].cast(cfa_t.yield_state))
449	if ys == '_X15__NO_PREEMPTIONKM19__Preemption_Reason_1':
450	state = str(thread['state'].cast(cfa_t.thread_state))
451	elif ys == '_X18__ALARM_PREEMPTIONKM19__Preemption_Reason_1':
452	state = 'preempted'
453	elif ys == '_X19__MANUAL_PREEMPTIONKM19__Preemption_Reason_1':
454	state = 'yield'
455	elif ys == '_X17__POLL_PREEMPTIONKM19__Preemption_Reason_1':
456	state = 'poll'
457	else:
458	print("error: thread {} in undefined preemption state {}".format(thread, ys))
459	state = 'error'
460	self.print_formatted(marked, tid, thread['self_cor']['name'].string(), state, str(thread))
461
462	def print_threads_by_cluster(self, cluster, print_system = False):
463	# Iterate through a circular linked list of tasks and print out its
464	# name along with address associated to each cluster
465	threads = lookup_threads_by_cluster(cluster)
466	if not threads:
467	return
468
469	running_thread = find_curr_thread()
470	if running_thread is None:
471	print('Could not identify current thread')
472
473	self.print_formatted(False, '', 'Name', 'State', 'Address')
474	for t in threads:
475	if not t.is_system() or print_system:
476	self.print_thread(t.value, t.tid, t.value == running_thread if running_thread else False)
477
478	print()
479
480	def print_all_threads(self):
481	for c in all_clusters():
482	self.print_threads_by_cluster(c, False)
483
484	def invoke(self, arg, from_tty):
485	"""
486	@arg: str
487	@from_tty: bool
488	"""
489	if not is_cforall():
490	return
491
492	if not arg:
493	cluster = lookup_cluster()
494	if not cluster:
495	print("Could not find Main Cluster")
496	return
497
498	# only tasks and main
499	self.print_threads_by_cluster(cluster, False)
500
501	elif arg == 'all':
502	# all threads, all clusters
503	self.print_all_threads()
504
505	else:
506	cluster = lookup_cluster(arg)
507	if not cluster:
508	print("No matching cluster")
509	return
510
511	# all tasks, specified cluster
512	self.print_threads_by_cluster(cluster, True)
513
514
515	############
516	class Thread(gdb.Command):
517	"""Cforall: Switch to specified user threads
518	Usage:
519	cfathread <id> : switch stack to thread id on main cluster
520	cfathread 0x<address> : switch stack to thread on any cluster
521	cfathread <id> <clusterName> : switch stack to thread on specified cluster
522	"""
523	def __init__(self):
524	# The first parameter of the line below is the name of the command. You
525	# can call it 'uc++ task'
526	super(Thread, self).__init__('cfathread', gdb.COMMAND_USER)
527
528	############################ AUXILIARY FUNCTIONS #########################
529
530	def switchto(self, thread):
531	"""Change to a new task by switching to a different stack and manually
532	adjusting sp, fp and pc
533	@task_address: str
534	2 supported format:
535	in hex format
536	<hex_address>: literal hexadecimal address
537	Ex: 0xffffff
538	in name of the pointer to the task
539	"task_name": pointer of the variable name of the cluster
540	Ex: T* s -> task_name = s
541	Return: gdb.value of the cluster's address
542	"""
543	try:
544	if not gdb.lookup_symbol('__cfactx_switch'):
545	print('__cfactx_switch symbol is unavailable')
546	return
547	except:
548	print('here 3')
549
550	cfa_t = get_cfa_types()
551
552	state = thread['state'].cast(cfa_t.thread_state)
553	try:
554	if state == gdb.parse_and_eval('Halted'):
555	print('Cannot switch to a terminated thread')
556	return
557
558	if state == gdb.parse_and_eval('Start'):
559	print('Cannjot switch to a thread not yet run')
560	return
561	except:
562	print("here 2")
563	return
564
565
566	context = thread['context']
567
568
569
570	# must be at frame 0 to set pc register
571	gdb.execute('select-frame 0')
572	if gdb.selected_frame().architecture().name() != 'i386:x86-64':
573	print('gdb debugging only supported for i386:x86-64 for now')
574	return
575
576	# gdb seems to handle things much better if we pretend we just entered the context switch
577	# pretend the pc is __cfactx_switch and adjust the sp, base pointer doesn't need to change
578	# lookup for sp,fp and uSwitch
579	xsp = context['SP'] + 40 # 40 = 5 64bit registers : %r15, %r14, %r13, %r12, %rbx WARNING: x64 specific
580	xfp = context['FP']
581
582	# convert string so we can strip out the address
583	try:
584	xpc = get_addr(gdb.parse_and_eval('__cfactx_switch').address)
585	except:
586	print("here")
587	return
588
589	# push sp, fp, pc into a global stack
590	global STACK
591	sp = gdb.parse_and_eval('$sp')
592	fp = gdb.parse_and_eval('$fp')
593	pc = gdb.parse_and_eval('$pc')
594	stack_info = StackInfo(sp = sp, fp = fp, pc = pc)
595	STACK.append(stack_info)
596
597	# update registers for new task
598	# print('switching to {} ({}) : [{}, {}, {}]'.format(thread['self_cor']['name'].string(), str(thread), str(xsp), str(xfp), str(xpc)))
599	print('switching to thread {} ({})'.format(str(thread), thread['self_cor']['name'].string()))
600	gdb.execute('set $rsp={}'.format(xsp))
601	gdb.execute('set $rbp={}'.format(xfp))
602	gdb.execute('set $pc={}'.format(xpc))
603
604	def find_matching_gdb_thread_id():
605	"""
606	Parse the str from info thread to get the number
607	"""
608	info_thread_str = gdb.execute('info thread', to_string=True).splitlines()
609	for thread_str in info_thread_str:
610	if thread_str.find('this={}'.format(task)) != -1:
611	thread_id_pattern = r'^\*?\s+(\d+)\s+Thread'
612	# retrive gdb thread id
613	return re.match(thread_id_pattern, thread_str).group(1)
614
615	# check if the task is running or not
616	if task_state == gdb.parse_and_eval('uBaseTask::Running'):
617	# find the equivalent thread from info thread
618	gdb_thread_id = find_matching_gdb_thread_id()
619	if gdb_thread_id is None:
620	print('cannot find the thread id to switch to')
621	return
622	# switch to that thread based using thread command
623	gdb.execute('thread {}'.format(gdb_thread_id))
624
625	def switchto_id(self, tid, cluster):
626	"""
627	@cluster: cluster object
628	@tid: int
629	"""
630	threads = lookup_threads_by_cluster( cluster )
631
632	for t in threads:
633	if t.tid == tid:
634	self.switchto(t.value)
635	return
636
637	print("Cound not find thread by id '{}'".format(tid))
638
639	def invoke(self, arg, from_tty):
640	"""
641	@arg: str
642	@from_tty: bool
643	"""
644	if not is_cforall():
645	return
646
647	argv = parse(arg)
648	if argv[0].isdigit():
649	cname = " ".join(argv[1:]) if len(argv) > 1 else None
650	cluster = lookup_cluster(cname)
651	if not cluster:
652	print("Could not find cluster '{}'".format(cname if cname else "Main Cluster"))
653	return
654
655	try:
656	tid = int(argv[0])
657	except:
658	print("'{}' not a valid thread id".format(argv[0]))
659	print_usage(self)
660	return
661
662	# by id, userCluster
663	self.switchto_id(tid, cluster)
664
665	elif argv[0].startswith('0x') or argv[0].startswith('0X'):
666	self.switchto(argv[0]) # by address, any cluster
667
668	############
669	class PrevThread(gdb.Command):
670	"""Switch back to previous task on the stack"""
671	usage_msg = 'prevtask'
672
673	def __init__(self):
674	super(PrevThread, self).__init__('prevtask', gdb.COMMAND_USER)
675
676	def invoke(self, arg, from_tty):
677	"""
678	@arg: str
679	@from_tty: bool
680	"""
681	global STACK
682	if len(STACK) != 0:
683	# must be at frame 0 to set pc register
684	gdb.execute('select-frame 0')
685
686	# pop stack
687	stack_info = STACK.pop()
688	pc = get_addr(stack_info.pc)
689	sp = stack_info.sp
690	fp = stack_info.fp
691
692	# pop sp, fp, pc from global stack
693	adjust_stack(pc, fp, sp)
694
695	# must be at C++ frame to access C++ vars
696	gdb.execute('frame 1')
697	else:
698	print('empty stack')
699
700	class ResetOriginFrame(gdb.Command):
701	"""Reset to the origin frame prior to continue execution again"""
702	usage_msg = 'resetOriginFrame'
703	def __init__(self):
704	super(ResetOriginFrame, self).__init__('reset', gdb.COMMAND_USER)
705
706	def invoke(self, arg, from_tty):
707	"""
708	@arg: str
709	@from_tty: bool
710	"""
711	global STACK
712	if len(STACK) != 0:
713	stack_info = STACK.pop(0)
714	STACK.clear()
715	pc = get_addr(stack_info.pc)
716	sp = stack_info.sp
717	fp = stack_info.fp
718
719	# pop sp, fp, pc from global stack
720	adjust_stack(pc, fp, sp)
721
722	# must be at C++ frame to access C++ vars
723	gdb.execute('frame 1')
724	#else:
725	#print('reset: empty stack') #probably does not have to print msg
726
727	Clusters()
728	Processors()
729	ResetOriginFrame()
730	PrevThread()
731	Threads()
732	Thread()
733
734	# Local Variables: #
735	# mode: Python #
736	# End: #

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