xref: /openbmc/linux/tools/perf/util/cs-etm.c (revision 86db9f28)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright(C) 2015-2018 Linaro Limited.
4  *
5  * Author: Tor Jeremiassen <tor@ti.com>
6  * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/err.h>
11 #include <linux/kernel.h>
12 #include <linux/log2.h>
13 #include <linux/types.h>
14 #include <linux/zalloc.h>
15 
16 #include <opencsd/ocsd_if_types.h>
17 #include <stdlib.h>
18 
19 #include "auxtrace.h"
20 #include "color.h"
21 #include "cs-etm.h"
22 #include "cs-etm-decoder/cs-etm-decoder.h"
23 #include "debug.h"
24 #include "dso.h"
25 #include "evlist.h"
26 #include "intlist.h"
27 #include "machine.h"
28 #include "map.h"
29 #include "perf.h"
30 #include "session.h"
31 #include "map_symbol.h"
32 #include "branch.h"
33 #include "symbol.h"
34 #include "tool.h"
35 #include "thread.h"
36 #include "thread-stack.h"
37 #include <tools/libc_compat.h>
38 #include "util/synthetic-events.h"
39 
40 #define MAX_TIMESTAMP (~0ULL)
41 
42 struct cs_etm_auxtrace {
43 	struct auxtrace auxtrace;
44 	struct auxtrace_queues queues;
45 	struct auxtrace_heap heap;
46 	struct itrace_synth_opts synth_opts;
47 	struct perf_session *session;
48 	struct machine *machine;
49 	struct thread *unknown_thread;
50 
51 	u8 timeless_decoding;
52 	u8 snapshot_mode;
53 	u8 data_queued;
54 	u8 sample_branches;
55 	u8 sample_instructions;
56 
57 	int num_cpu;
58 	u32 auxtrace_type;
59 	u64 branches_sample_type;
60 	u64 branches_id;
61 	u64 instructions_sample_type;
62 	u64 instructions_sample_period;
63 	u64 instructions_id;
64 	u64 **metadata;
65 	u64 kernel_start;
66 	unsigned int pmu_type;
67 };
68 
69 struct cs_etm_traceid_queue {
70 	u8 trace_chan_id;
71 	pid_t pid, tid;
72 	u64 period_instructions;
73 	size_t last_branch_pos;
74 	union perf_event *event_buf;
75 	struct thread *thread;
76 	struct branch_stack *last_branch;
77 	struct branch_stack *last_branch_rb;
78 	struct cs_etm_packet *prev_packet;
79 	struct cs_etm_packet *packet;
80 	struct cs_etm_packet_queue packet_queue;
81 };
82 
83 struct cs_etm_queue {
84 	struct cs_etm_auxtrace *etm;
85 	struct cs_etm_decoder *decoder;
86 	struct auxtrace_buffer *buffer;
87 	unsigned int queue_nr;
88 	u8 pending_timestamp;
89 	u64 offset;
90 	const unsigned char *buf;
91 	size_t buf_len, buf_used;
92 	/* Conversion between traceID and index in traceid_queues array */
93 	struct intlist *traceid_queues_list;
94 	struct cs_etm_traceid_queue **traceid_queues;
95 };
96 
97 static int cs_etm__update_queues(struct cs_etm_auxtrace *etm);
98 static int cs_etm__process_queues(struct cs_etm_auxtrace *etm);
99 static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
100 					   pid_t tid);
101 static int cs_etm__get_data_block(struct cs_etm_queue *etmq);
102 static int cs_etm__decode_data_block(struct cs_etm_queue *etmq);
103 
104 /* PTMs ETMIDR [11:8] set to b0011 */
105 #define ETMIDR_PTM_VERSION 0x00000300
106 
107 /*
108  * A struct auxtrace_heap_item only has a queue_nr and a timestamp to
109  * work with.  One option is to modify to auxtrace_heap_XYZ() API or simply
110  * encode the etm queue number as the upper 16 bit and the channel as
111  * the lower 16 bit.
112  */
113 #define TO_CS_QUEUE_NR(queue_nr, trace_id_chan)	\
114 		      (queue_nr << 16 | trace_chan_id)
115 #define TO_QUEUE_NR(cs_queue_nr) (cs_queue_nr >> 16)
116 #define TO_TRACE_CHAN_ID(cs_queue_nr) (cs_queue_nr & 0x0000ffff)
117 
118 static u32 cs_etm__get_v7_protocol_version(u32 etmidr)
119 {
120 	etmidr &= ETMIDR_PTM_VERSION;
121 
122 	if (etmidr == ETMIDR_PTM_VERSION)
123 		return CS_ETM_PROTO_PTM;
124 
125 	return CS_ETM_PROTO_ETMV3;
126 }
127 
128 static int cs_etm__get_magic(u8 trace_chan_id, u64 *magic)
129 {
130 	struct int_node *inode;
131 	u64 *metadata;
132 
133 	inode = intlist__find(traceid_list, trace_chan_id);
134 	if (!inode)
135 		return -EINVAL;
136 
137 	metadata = inode->priv;
138 	*magic = metadata[CS_ETM_MAGIC];
139 	return 0;
140 }
141 
142 int cs_etm__get_cpu(u8 trace_chan_id, int *cpu)
143 {
144 	struct int_node *inode;
145 	u64 *metadata;
146 
147 	inode = intlist__find(traceid_list, trace_chan_id);
148 	if (!inode)
149 		return -EINVAL;
150 
151 	metadata = inode->priv;
152 	*cpu = (int)metadata[CS_ETM_CPU];
153 	return 0;
154 }
155 
156 void cs_etm__etmq_set_traceid_queue_timestamp(struct cs_etm_queue *etmq,
157 					      u8 trace_chan_id)
158 {
159 	/*
160 	 * Wnen a timestamp packet is encountered the backend code
161 	 * is stopped so that the front end has time to process packets
162 	 * that were accumulated in the traceID queue.  Since there can
163 	 * be more than one channel per cs_etm_queue, we need to specify
164 	 * what traceID queue needs servicing.
165 	 */
166 	etmq->pending_timestamp = trace_chan_id;
167 }
168 
169 static u64 cs_etm__etmq_get_timestamp(struct cs_etm_queue *etmq,
170 				      u8 *trace_chan_id)
171 {
172 	struct cs_etm_packet_queue *packet_queue;
173 
174 	if (!etmq->pending_timestamp)
175 		return 0;
176 
177 	if (trace_chan_id)
178 		*trace_chan_id = etmq->pending_timestamp;
179 
180 	packet_queue = cs_etm__etmq_get_packet_queue(etmq,
181 						     etmq->pending_timestamp);
182 	if (!packet_queue)
183 		return 0;
184 
185 	/* Acknowledge pending status */
186 	etmq->pending_timestamp = 0;
187 
188 	/* See function cs_etm_decoder__do_{hard|soft}_timestamp() */
189 	return packet_queue->timestamp;
190 }
191 
192 static void cs_etm__clear_packet_queue(struct cs_etm_packet_queue *queue)
193 {
194 	int i;
195 
196 	queue->head = 0;
197 	queue->tail = 0;
198 	queue->packet_count = 0;
199 	for (i = 0; i < CS_ETM_PACKET_MAX_BUFFER; i++) {
200 		queue->packet_buffer[i].isa = CS_ETM_ISA_UNKNOWN;
201 		queue->packet_buffer[i].start_addr = CS_ETM_INVAL_ADDR;
202 		queue->packet_buffer[i].end_addr = CS_ETM_INVAL_ADDR;
203 		queue->packet_buffer[i].instr_count = 0;
204 		queue->packet_buffer[i].last_instr_taken_branch = false;
205 		queue->packet_buffer[i].last_instr_size = 0;
206 		queue->packet_buffer[i].last_instr_type = 0;
207 		queue->packet_buffer[i].last_instr_subtype = 0;
208 		queue->packet_buffer[i].last_instr_cond = 0;
209 		queue->packet_buffer[i].flags = 0;
210 		queue->packet_buffer[i].exception_number = UINT32_MAX;
211 		queue->packet_buffer[i].trace_chan_id = UINT8_MAX;
212 		queue->packet_buffer[i].cpu = INT_MIN;
213 	}
214 }
215 
216 static void cs_etm__clear_all_packet_queues(struct cs_etm_queue *etmq)
217 {
218 	int idx;
219 	struct int_node *inode;
220 	struct cs_etm_traceid_queue *tidq;
221 	struct intlist *traceid_queues_list = etmq->traceid_queues_list;
222 
223 	intlist__for_each_entry(inode, traceid_queues_list) {
224 		idx = (int)(intptr_t)inode->priv;
225 		tidq = etmq->traceid_queues[idx];
226 		cs_etm__clear_packet_queue(&tidq->packet_queue);
227 	}
228 }
229 
230 static int cs_etm__init_traceid_queue(struct cs_etm_queue *etmq,
231 				      struct cs_etm_traceid_queue *tidq,
232 				      u8 trace_chan_id)
233 {
234 	int rc = -ENOMEM;
235 	struct auxtrace_queue *queue;
236 	struct cs_etm_auxtrace *etm = etmq->etm;
237 
238 	cs_etm__clear_packet_queue(&tidq->packet_queue);
239 
240 	queue = &etmq->etm->queues.queue_array[etmq->queue_nr];
241 	tidq->tid = queue->tid;
242 	tidq->pid = -1;
243 	tidq->trace_chan_id = trace_chan_id;
244 
245 	tidq->packet = zalloc(sizeof(struct cs_etm_packet));
246 	if (!tidq->packet)
247 		goto out;
248 
249 	tidq->prev_packet = zalloc(sizeof(struct cs_etm_packet));
250 	if (!tidq->prev_packet)
251 		goto out_free;
252 
253 	if (etm->synth_opts.last_branch) {
254 		size_t sz = sizeof(struct branch_stack);
255 
256 		sz += etm->synth_opts.last_branch_sz *
257 		      sizeof(struct branch_entry);
258 		tidq->last_branch = zalloc(sz);
259 		if (!tidq->last_branch)
260 			goto out_free;
261 		tidq->last_branch_rb = zalloc(sz);
262 		if (!tidq->last_branch_rb)
263 			goto out_free;
264 	}
265 
266 	tidq->event_buf = malloc(PERF_SAMPLE_MAX_SIZE);
267 	if (!tidq->event_buf)
268 		goto out_free;
269 
270 	return 0;
271 
272 out_free:
273 	zfree(&tidq->last_branch_rb);
274 	zfree(&tidq->last_branch);
275 	zfree(&tidq->prev_packet);
276 	zfree(&tidq->packet);
277 out:
278 	return rc;
279 }
280 
281 static struct cs_etm_traceid_queue
282 *cs_etm__etmq_get_traceid_queue(struct cs_etm_queue *etmq, u8 trace_chan_id)
283 {
284 	int idx;
285 	struct int_node *inode;
286 	struct intlist *traceid_queues_list;
287 	struct cs_etm_traceid_queue *tidq, **traceid_queues;
288 	struct cs_etm_auxtrace *etm = etmq->etm;
289 
290 	if (etm->timeless_decoding)
291 		trace_chan_id = CS_ETM_PER_THREAD_TRACEID;
292 
293 	traceid_queues_list = etmq->traceid_queues_list;
294 
295 	/*
296 	 * Check if the traceid_queue exist for this traceID by looking
297 	 * in the queue list.
298 	 */
299 	inode = intlist__find(traceid_queues_list, trace_chan_id);
300 	if (inode) {
301 		idx = (int)(intptr_t)inode->priv;
302 		return etmq->traceid_queues[idx];
303 	}
304 
305 	/* We couldn't find a traceid_queue for this traceID, allocate one */
306 	tidq = malloc(sizeof(*tidq));
307 	if (!tidq)
308 		return NULL;
309 
310 	memset(tidq, 0, sizeof(*tidq));
311 
312 	/* Get a valid index for the new traceid_queue */
313 	idx = intlist__nr_entries(traceid_queues_list);
314 	/* Memory for the inode is free'ed in cs_etm_free_traceid_queues () */
315 	inode = intlist__findnew(traceid_queues_list, trace_chan_id);
316 	if (!inode)
317 		goto out_free;
318 
319 	/* Associate this traceID with this index */
320 	inode->priv = (void *)(intptr_t)idx;
321 
322 	if (cs_etm__init_traceid_queue(etmq, tidq, trace_chan_id))
323 		goto out_free;
324 
325 	/* Grow the traceid_queues array by one unit */
326 	traceid_queues = etmq->traceid_queues;
327 	traceid_queues = reallocarray(traceid_queues,
328 				      idx + 1,
329 				      sizeof(*traceid_queues));
330 
331 	/*
332 	 * On failure reallocarray() returns NULL and the original block of
333 	 * memory is left untouched.
334 	 */
335 	if (!traceid_queues)
336 		goto out_free;
337 
338 	traceid_queues[idx] = tidq;
339 	etmq->traceid_queues = traceid_queues;
340 
341 	return etmq->traceid_queues[idx];
342 
343 out_free:
344 	/*
345 	 * Function intlist__remove() removes the inode from the list
346 	 * and delete the memory associated to it.
347 	 */
348 	intlist__remove(traceid_queues_list, inode);
349 	free(tidq);
350 
351 	return NULL;
352 }
353 
354 struct cs_etm_packet_queue
355 *cs_etm__etmq_get_packet_queue(struct cs_etm_queue *etmq, u8 trace_chan_id)
356 {
357 	struct cs_etm_traceid_queue *tidq;
358 
359 	tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
360 	if (tidq)
361 		return &tidq->packet_queue;
362 
363 	return NULL;
364 }
365 
366 static void cs_etm__packet_dump(const char *pkt_string)
367 {
368 	const char *color = PERF_COLOR_BLUE;
369 	int len = strlen(pkt_string);
370 
371 	if (len && (pkt_string[len-1] == '\n'))
372 		color_fprintf(stdout, color, "	%s", pkt_string);
373 	else
374 		color_fprintf(stdout, color, "	%s\n", pkt_string);
375 
376 	fflush(stdout);
377 }
378 
379 static void cs_etm__set_trace_param_etmv3(struct cs_etm_trace_params *t_params,
380 					  struct cs_etm_auxtrace *etm, int idx,
381 					  u32 etmidr)
382 {
383 	u64 **metadata = etm->metadata;
384 
385 	t_params[idx].protocol = cs_etm__get_v7_protocol_version(etmidr);
386 	t_params[idx].etmv3.reg_ctrl = metadata[idx][CS_ETM_ETMCR];
387 	t_params[idx].etmv3.reg_trc_id = metadata[idx][CS_ETM_ETMTRACEIDR];
388 }
389 
390 static void cs_etm__set_trace_param_etmv4(struct cs_etm_trace_params *t_params,
391 					  struct cs_etm_auxtrace *etm, int idx)
392 {
393 	u64 **metadata = etm->metadata;
394 
395 	t_params[idx].protocol = CS_ETM_PROTO_ETMV4i;
396 	t_params[idx].etmv4.reg_idr0 = metadata[idx][CS_ETMV4_TRCIDR0];
397 	t_params[idx].etmv4.reg_idr1 = metadata[idx][CS_ETMV4_TRCIDR1];
398 	t_params[idx].etmv4.reg_idr2 = metadata[idx][CS_ETMV4_TRCIDR2];
399 	t_params[idx].etmv4.reg_idr8 = metadata[idx][CS_ETMV4_TRCIDR8];
400 	t_params[idx].etmv4.reg_configr = metadata[idx][CS_ETMV4_TRCCONFIGR];
401 	t_params[idx].etmv4.reg_traceidr = metadata[idx][CS_ETMV4_TRCTRACEIDR];
402 }
403 
404 static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
405 				     struct cs_etm_auxtrace *etm)
406 {
407 	int i;
408 	u32 etmidr;
409 	u64 architecture;
410 
411 	for (i = 0; i < etm->num_cpu; i++) {
412 		architecture = etm->metadata[i][CS_ETM_MAGIC];
413 
414 		switch (architecture) {
415 		case __perf_cs_etmv3_magic:
416 			etmidr = etm->metadata[i][CS_ETM_ETMIDR];
417 			cs_etm__set_trace_param_etmv3(t_params, etm, i, etmidr);
418 			break;
419 		case __perf_cs_etmv4_magic:
420 			cs_etm__set_trace_param_etmv4(t_params, etm, i);
421 			break;
422 		default:
423 			return -EINVAL;
424 		}
425 	}
426 
427 	return 0;
428 }
429 
430 static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
431 				       struct cs_etm_queue *etmq,
432 				       enum cs_etm_decoder_operation mode)
433 {
434 	int ret = -EINVAL;
435 
436 	if (!(mode < CS_ETM_OPERATION_MAX))
437 		goto out;
438 
439 	d_params->packet_printer = cs_etm__packet_dump;
440 	d_params->operation = mode;
441 	d_params->data = etmq;
442 	d_params->formatted = true;
443 	d_params->fsyncs = false;
444 	d_params->hsyncs = false;
445 	d_params->frame_aligned = true;
446 
447 	ret = 0;
448 out:
449 	return ret;
450 }
451 
452 static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
453 			       struct auxtrace_buffer *buffer)
454 {
455 	int ret;
456 	const char *color = PERF_COLOR_BLUE;
457 	struct cs_etm_decoder_params d_params;
458 	struct cs_etm_trace_params *t_params;
459 	struct cs_etm_decoder *decoder;
460 	size_t buffer_used = 0;
461 
462 	fprintf(stdout, "\n");
463 	color_fprintf(stdout, color,
464 		     ". ... CoreSight ETM Trace data: size %zu bytes\n",
465 		     buffer->size);
466 
467 	/* Use metadata to fill in trace parameters for trace decoder */
468 	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
469 
470 	if (!t_params)
471 		return;
472 
473 	if (cs_etm__init_trace_params(t_params, etm))
474 		goto out_free;
475 
476 	/* Set decoder parameters to simply print the trace packets */
477 	if (cs_etm__init_decoder_params(&d_params, NULL,
478 					CS_ETM_OPERATION_PRINT))
479 		goto out_free;
480 
481 	decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
482 
483 	if (!decoder)
484 		goto out_free;
485 	do {
486 		size_t consumed;
487 
488 		ret = cs_etm_decoder__process_data_block(
489 				decoder, buffer->offset,
490 				&((u8 *)buffer->data)[buffer_used],
491 				buffer->size - buffer_used, &consumed);
492 		if (ret)
493 			break;
494 
495 		buffer_used += consumed;
496 	} while (buffer_used < buffer->size);
497 
498 	cs_etm_decoder__free(decoder);
499 
500 out_free:
501 	zfree(&t_params);
502 }
503 
504 static int cs_etm__flush_events(struct perf_session *session,
505 				struct perf_tool *tool)
506 {
507 	int ret;
508 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
509 						   struct cs_etm_auxtrace,
510 						   auxtrace);
511 	if (dump_trace)
512 		return 0;
513 
514 	if (!tool->ordered_events)
515 		return -EINVAL;
516 
517 	ret = cs_etm__update_queues(etm);
518 
519 	if (ret < 0)
520 		return ret;
521 
522 	if (etm->timeless_decoding)
523 		return cs_etm__process_timeless_queues(etm, -1);
524 
525 	return cs_etm__process_queues(etm);
526 }
527 
528 static void cs_etm__free_traceid_queues(struct cs_etm_queue *etmq)
529 {
530 	int idx;
531 	uintptr_t priv;
532 	struct int_node *inode, *tmp;
533 	struct cs_etm_traceid_queue *tidq;
534 	struct intlist *traceid_queues_list = etmq->traceid_queues_list;
535 
536 	intlist__for_each_entry_safe(inode, tmp, traceid_queues_list) {
537 		priv = (uintptr_t)inode->priv;
538 		idx = priv;
539 
540 		/* Free this traceid_queue from the array */
541 		tidq = etmq->traceid_queues[idx];
542 		thread__zput(tidq->thread);
543 		zfree(&tidq->event_buf);
544 		zfree(&tidq->last_branch);
545 		zfree(&tidq->last_branch_rb);
546 		zfree(&tidq->prev_packet);
547 		zfree(&tidq->packet);
548 		zfree(&tidq);
549 
550 		/*
551 		 * Function intlist__remove() removes the inode from the list
552 		 * and delete the memory associated to it.
553 		 */
554 		intlist__remove(traceid_queues_list, inode);
555 	}
556 
557 	/* Then the RB tree itself */
558 	intlist__delete(traceid_queues_list);
559 	etmq->traceid_queues_list = NULL;
560 
561 	/* finally free the traceid_queues array */
562 	zfree(&etmq->traceid_queues);
563 }
564 
565 static void cs_etm__free_queue(void *priv)
566 {
567 	struct cs_etm_queue *etmq = priv;
568 
569 	if (!etmq)
570 		return;
571 
572 	cs_etm_decoder__free(etmq->decoder);
573 	cs_etm__free_traceid_queues(etmq);
574 	free(etmq);
575 }
576 
577 static void cs_etm__free_events(struct perf_session *session)
578 {
579 	unsigned int i;
580 	struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
581 						   struct cs_etm_auxtrace,
582 						   auxtrace);
583 	struct auxtrace_queues *queues = &aux->queues;
584 
585 	for (i = 0; i < queues->nr_queues; i++) {
586 		cs_etm__free_queue(queues->queue_array[i].priv);
587 		queues->queue_array[i].priv = NULL;
588 	}
589 
590 	auxtrace_queues__free(queues);
591 }
592 
593 static void cs_etm__free(struct perf_session *session)
594 {
595 	int i;
596 	struct int_node *inode, *tmp;
597 	struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
598 						   struct cs_etm_auxtrace,
599 						   auxtrace);
600 	cs_etm__free_events(session);
601 	session->auxtrace = NULL;
602 
603 	/* First remove all traceID/metadata nodes for the RB tree */
604 	intlist__for_each_entry_safe(inode, tmp, traceid_list)
605 		intlist__remove(traceid_list, inode);
606 	/* Then the RB tree itself */
607 	intlist__delete(traceid_list);
608 
609 	for (i = 0; i < aux->num_cpu; i++)
610 		zfree(&aux->metadata[i]);
611 
612 	thread__zput(aux->unknown_thread);
613 	zfree(&aux->metadata);
614 	zfree(&aux);
615 }
616 
617 static u8 cs_etm__cpu_mode(struct cs_etm_queue *etmq, u64 address)
618 {
619 	struct machine *machine;
620 
621 	machine = etmq->etm->machine;
622 
623 	if (address >= etmq->etm->kernel_start) {
624 		if (machine__is_host(machine))
625 			return PERF_RECORD_MISC_KERNEL;
626 		else
627 			return PERF_RECORD_MISC_GUEST_KERNEL;
628 	} else {
629 		if (machine__is_host(machine))
630 			return PERF_RECORD_MISC_USER;
631 		else if (perf_guest)
632 			return PERF_RECORD_MISC_GUEST_USER;
633 		else
634 			return PERF_RECORD_MISC_HYPERVISOR;
635 	}
636 }
637 
638 static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
639 			      u64 address, size_t size, u8 *buffer)
640 {
641 	u8  cpumode;
642 	u64 offset;
643 	int len;
644 	struct thread *thread;
645 	struct machine *machine;
646 	struct addr_location al;
647 	struct cs_etm_traceid_queue *tidq;
648 
649 	if (!etmq)
650 		return 0;
651 
652 	machine = etmq->etm->machine;
653 	cpumode = cs_etm__cpu_mode(etmq, address);
654 	tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
655 	if (!tidq)
656 		return 0;
657 
658 	thread = tidq->thread;
659 	if (!thread) {
660 		if (cpumode != PERF_RECORD_MISC_KERNEL)
661 			return 0;
662 		thread = etmq->etm->unknown_thread;
663 	}
664 
665 	if (!thread__find_map(thread, cpumode, address, &al) || !al.map->dso)
666 		return 0;
667 
668 	if (al.map->dso->data.status == DSO_DATA_STATUS_ERROR &&
669 	    dso__data_status_seen(al.map->dso, DSO_DATA_STATUS_SEEN_ITRACE))
670 		return 0;
671 
672 	offset = al.map->map_ip(al.map, address);
673 
674 	map__load(al.map);
675 
676 	len = dso__data_read_offset(al.map->dso, machine, offset, buffer, size);
677 
678 	if (len <= 0)
679 		return 0;
680 
681 	return len;
682 }
683 
684 static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
685 {
686 	struct cs_etm_decoder_params d_params;
687 	struct cs_etm_trace_params  *t_params = NULL;
688 	struct cs_etm_queue *etmq;
689 
690 	etmq = zalloc(sizeof(*etmq));
691 	if (!etmq)
692 		return NULL;
693 
694 	etmq->traceid_queues_list = intlist__new(NULL);
695 	if (!etmq->traceid_queues_list)
696 		goto out_free;
697 
698 	/* Use metadata to fill in trace parameters for trace decoder */
699 	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
700 
701 	if (!t_params)
702 		goto out_free;
703 
704 	if (cs_etm__init_trace_params(t_params, etm))
705 		goto out_free;
706 
707 	/* Set decoder parameters to decode trace packets */
708 	if (cs_etm__init_decoder_params(&d_params, etmq,
709 					CS_ETM_OPERATION_DECODE))
710 		goto out_free;
711 
712 	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
713 
714 	if (!etmq->decoder)
715 		goto out_free;
716 
717 	/*
718 	 * Register a function to handle all memory accesses required by
719 	 * the trace decoder library.
720 	 */
721 	if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
722 					      0x0L, ((u64) -1L),
723 					      cs_etm__mem_access))
724 		goto out_free_decoder;
725 
726 	zfree(&t_params);
727 	return etmq;
728 
729 out_free_decoder:
730 	cs_etm_decoder__free(etmq->decoder);
731 out_free:
732 	intlist__delete(etmq->traceid_queues_list);
733 	free(etmq);
734 
735 	return NULL;
736 }
737 
738 static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
739 			       struct auxtrace_queue *queue,
740 			       unsigned int queue_nr)
741 {
742 	int ret = 0;
743 	unsigned int cs_queue_nr;
744 	u8 trace_chan_id;
745 	u64 timestamp;
746 	struct cs_etm_queue *etmq = queue->priv;
747 
748 	if (list_empty(&queue->head) || etmq)
749 		goto out;
750 
751 	etmq = cs_etm__alloc_queue(etm);
752 
753 	if (!etmq) {
754 		ret = -ENOMEM;
755 		goto out;
756 	}
757 
758 	queue->priv = etmq;
759 	etmq->etm = etm;
760 	etmq->queue_nr = queue_nr;
761 	etmq->offset = 0;
762 
763 	if (etm->timeless_decoding)
764 		goto out;
765 
766 	/*
767 	 * We are under a CPU-wide trace scenario.  As such we need to know
768 	 * when the code that generated the traces started to execute so that
769 	 * it can be correlated with execution on other CPUs.  So we get a
770 	 * handle on the beginning of traces and decode until we find a
771 	 * timestamp.  The timestamp is then added to the auxtrace min heap
772 	 * in order to know what nibble (of all the etmqs) to decode first.
773 	 */
774 	while (1) {
775 		/*
776 		 * Fetch an aux_buffer from this etmq.  Bail if no more
777 		 * blocks or an error has been encountered.
778 		 */
779 		ret = cs_etm__get_data_block(etmq);
780 		if (ret <= 0)
781 			goto out;
782 
783 		/*
784 		 * Run decoder on the trace block.  The decoder will stop when
785 		 * encountering a timestamp, a full packet queue or the end of
786 		 * trace for that block.
787 		 */
788 		ret = cs_etm__decode_data_block(etmq);
789 		if (ret)
790 			goto out;
791 
792 		/*
793 		 * Function cs_etm_decoder__do_{hard|soft}_timestamp() does all
794 		 * the timestamp calculation for us.
795 		 */
796 		timestamp = cs_etm__etmq_get_timestamp(etmq, &trace_chan_id);
797 
798 		/* We found a timestamp, no need to continue. */
799 		if (timestamp)
800 			break;
801 
802 		/*
803 		 * We didn't find a timestamp so empty all the traceid packet
804 		 * queues before looking for another timestamp packet, either
805 		 * in the current data block or a new one.  Packets that were
806 		 * just decoded are useless since no timestamp has been
807 		 * associated with them.  As such simply discard them.
808 		 */
809 		cs_etm__clear_all_packet_queues(etmq);
810 	}
811 
812 	/*
813 	 * We have a timestamp.  Add it to the min heap to reflect when
814 	 * instructions conveyed by the range packets of this traceID queue
815 	 * started to execute.  Once the same has been done for all the traceID
816 	 * queues of each etmq, redenring and decoding can start in
817 	 * chronological order.
818 	 *
819 	 * Note that packets decoded above are still in the traceID's packet
820 	 * queue and will be processed in cs_etm__process_queues().
821 	 */
822 	cs_queue_nr = TO_CS_QUEUE_NR(queue_nr, trace_id_chan);
823 	ret = auxtrace_heap__add(&etm->heap, cs_queue_nr, timestamp);
824 out:
825 	return ret;
826 }
827 
828 static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
829 {
830 	unsigned int i;
831 	int ret;
832 
833 	if (!etm->kernel_start)
834 		etm->kernel_start = machine__kernel_start(etm->machine);
835 
836 	for (i = 0; i < etm->queues.nr_queues; i++) {
837 		ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
838 		if (ret)
839 			return ret;
840 	}
841 
842 	return 0;
843 }
844 
845 static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
846 {
847 	if (etm->queues.new_data) {
848 		etm->queues.new_data = false;
849 		return cs_etm__setup_queues(etm);
850 	}
851 
852 	return 0;
853 }
854 
855 static inline
856 void cs_etm__copy_last_branch_rb(struct cs_etm_queue *etmq,
857 				 struct cs_etm_traceid_queue *tidq)
858 {
859 	struct branch_stack *bs_src = tidq->last_branch_rb;
860 	struct branch_stack *bs_dst = tidq->last_branch;
861 	size_t nr = 0;
862 
863 	/*
864 	 * Set the number of records before early exit: ->nr is used to
865 	 * determine how many branches to copy from ->entries.
866 	 */
867 	bs_dst->nr = bs_src->nr;
868 
869 	/*
870 	 * Early exit when there is nothing to copy.
871 	 */
872 	if (!bs_src->nr)
873 		return;
874 
875 	/*
876 	 * As bs_src->entries is a circular buffer, we need to copy from it in
877 	 * two steps.  First, copy the branches from the most recently inserted
878 	 * branch ->last_branch_pos until the end of bs_src->entries buffer.
879 	 */
880 	nr = etmq->etm->synth_opts.last_branch_sz - tidq->last_branch_pos;
881 	memcpy(&bs_dst->entries[0],
882 	       &bs_src->entries[tidq->last_branch_pos],
883 	       sizeof(struct branch_entry) * nr);
884 
885 	/*
886 	 * If we wrapped around at least once, the branches from the beginning
887 	 * of the bs_src->entries buffer and until the ->last_branch_pos element
888 	 * are older valid branches: copy them over.  The total number of
889 	 * branches copied over will be equal to the number of branches asked by
890 	 * the user in last_branch_sz.
891 	 */
892 	if (bs_src->nr >= etmq->etm->synth_opts.last_branch_sz) {
893 		memcpy(&bs_dst->entries[nr],
894 		       &bs_src->entries[0],
895 		       sizeof(struct branch_entry) * tidq->last_branch_pos);
896 	}
897 }
898 
899 static inline
900 void cs_etm__reset_last_branch_rb(struct cs_etm_traceid_queue *tidq)
901 {
902 	tidq->last_branch_pos = 0;
903 	tidq->last_branch_rb->nr = 0;
904 }
905 
906 static inline int cs_etm__t32_instr_size(struct cs_etm_queue *etmq,
907 					 u8 trace_chan_id, u64 addr)
908 {
909 	u8 instrBytes[2];
910 
911 	cs_etm__mem_access(etmq, trace_chan_id, addr,
912 			   ARRAY_SIZE(instrBytes), instrBytes);
913 	/*
914 	 * T32 instruction size is indicated by bits[15:11] of the first
915 	 * 16-bit word of the instruction: 0b11101, 0b11110 and 0b11111
916 	 * denote a 32-bit instruction.
917 	 */
918 	return ((instrBytes[1] & 0xF8) >= 0xE8) ? 4 : 2;
919 }
920 
921 static inline u64 cs_etm__first_executed_instr(struct cs_etm_packet *packet)
922 {
923 	/* Returns 0 for the CS_ETM_DISCONTINUITY packet */
924 	if (packet->sample_type == CS_ETM_DISCONTINUITY)
925 		return 0;
926 
927 	return packet->start_addr;
928 }
929 
930 static inline
931 u64 cs_etm__last_executed_instr(const struct cs_etm_packet *packet)
932 {
933 	/* Returns 0 for the CS_ETM_DISCONTINUITY packet */
934 	if (packet->sample_type == CS_ETM_DISCONTINUITY)
935 		return 0;
936 
937 	return packet->end_addr - packet->last_instr_size;
938 }
939 
940 static inline u64 cs_etm__instr_addr(struct cs_etm_queue *etmq,
941 				     u64 trace_chan_id,
942 				     const struct cs_etm_packet *packet,
943 				     u64 offset)
944 {
945 	if (packet->isa == CS_ETM_ISA_T32) {
946 		u64 addr = packet->start_addr;
947 
948 		while (offset > 0) {
949 			addr += cs_etm__t32_instr_size(etmq,
950 						       trace_chan_id, addr);
951 			offset--;
952 		}
953 		return addr;
954 	}
955 
956 	/* Assume a 4 byte instruction size (A32/A64) */
957 	return packet->start_addr + offset * 4;
958 }
959 
960 static void cs_etm__update_last_branch_rb(struct cs_etm_queue *etmq,
961 					  struct cs_etm_traceid_queue *tidq)
962 {
963 	struct branch_stack *bs = tidq->last_branch_rb;
964 	struct branch_entry *be;
965 
966 	/*
967 	 * The branches are recorded in a circular buffer in reverse
968 	 * chronological order: we start recording from the last element of the
969 	 * buffer down.  After writing the first element of the stack, move the
970 	 * insert position back to the end of the buffer.
971 	 */
972 	if (!tidq->last_branch_pos)
973 		tidq->last_branch_pos = etmq->etm->synth_opts.last_branch_sz;
974 
975 	tidq->last_branch_pos -= 1;
976 
977 	be       = &bs->entries[tidq->last_branch_pos];
978 	be->from = cs_etm__last_executed_instr(tidq->prev_packet);
979 	be->to	 = cs_etm__first_executed_instr(tidq->packet);
980 	/* No support for mispredict */
981 	be->flags.mispred = 0;
982 	be->flags.predicted = 1;
983 
984 	/*
985 	 * Increment bs->nr until reaching the number of last branches asked by
986 	 * the user on the command line.
987 	 */
988 	if (bs->nr < etmq->etm->synth_opts.last_branch_sz)
989 		bs->nr += 1;
990 }
991 
992 static int cs_etm__inject_event(union perf_event *event,
993 			       struct perf_sample *sample, u64 type)
994 {
995 	event->header.size = perf_event__sample_event_size(sample, type, 0);
996 	return perf_event__synthesize_sample(event, type, 0, sample);
997 }
998 
999 
1000 static int
1001 cs_etm__get_trace(struct cs_etm_queue *etmq)
1002 {
1003 	struct auxtrace_buffer *aux_buffer = etmq->buffer;
1004 	struct auxtrace_buffer *old_buffer = aux_buffer;
1005 	struct auxtrace_queue *queue;
1006 
1007 	queue = &etmq->etm->queues.queue_array[etmq->queue_nr];
1008 
1009 	aux_buffer = auxtrace_buffer__next(queue, aux_buffer);
1010 
1011 	/* If no more data, drop the previous auxtrace_buffer and return */
1012 	if (!aux_buffer) {
1013 		if (old_buffer)
1014 			auxtrace_buffer__drop_data(old_buffer);
1015 		etmq->buf_len = 0;
1016 		return 0;
1017 	}
1018 
1019 	etmq->buffer = aux_buffer;
1020 
1021 	/* If the aux_buffer doesn't have data associated, try to load it */
1022 	if (!aux_buffer->data) {
1023 		/* get the file desc associated with the perf data file */
1024 		int fd = perf_data__fd(etmq->etm->session->data);
1025 
1026 		aux_buffer->data = auxtrace_buffer__get_data(aux_buffer, fd);
1027 		if (!aux_buffer->data)
1028 			return -ENOMEM;
1029 	}
1030 
1031 	/* If valid, drop the previous buffer */
1032 	if (old_buffer)
1033 		auxtrace_buffer__drop_data(old_buffer);
1034 
1035 	etmq->buf_used = 0;
1036 	etmq->buf_len = aux_buffer->size;
1037 	etmq->buf = aux_buffer->data;
1038 
1039 	return etmq->buf_len;
1040 }
1041 
1042 static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
1043 				    struct cs_etm_traceid_queue *tidq)
1044 {
1045 	if ((!tidq->thread) && (tidq->tid != -1))
1046 		tidq->thread = machine__find_thread(etm->machine, -1,
1047 						    tidq->tid);
1048 
1049 	if (tidq->thread)
1050 		tidq->pid = tidq->thread->pid_;
1051 }
1052 
1053 int cs_etm__etmq_set_tid(struct cs_etm_queue *etmq,
1054 			 pid_t tid, u8 trace_chan_id)
1055 {
1056 	int cpu, err = -EINVAL;
1057 	struct cs_etm_auxtrace *etm = etmq->etm;
1058 	struct cs_etm_traceid_queue *tidq;
1059 
1060 	tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
1061 	if (!tidq)
1062 		return err;
1063 
1064 	if (cs_etm__get_cpu(trace_chan_id, &cpu) < 0)
1065 		return err;
1066 
1067 	err = machine__set_current_tid(etm->machine, cpu, tid, tid);
1068 	if (err)
1069 		return err;
1070 
1071 	tidq->tid = tid;
1072 	thread__zput(tidq->thread);
1073 
1074 	cs_etm__set_pid_tid_cpu(etm, tidq);
1075 	return 0;
1076 }
1077 
1078 bool cs_etm__etmq_is_timeless(struct cs_etm_queue *etmq)
1079 {
1080 	return !!etmq->etm->timeless_decoding;
1081 }
1082 
1083 static void cs_etm__copy_insn(struct cs_etm_queue *etmq,
1084 			      u64 trace_chan_id,
1085 			      const struct cs_etm_packet *packet,
1086 			      struct perf_sample *sample)
1087 {
1088 	/*
1089 	 * It's pointless to read instructions for the CS_ETM_DISCONTINUITY
1090 	 * packet, so directly bail out with 'insn_len' = 0.
1091 	 */
1092 	if (packet->sample_type == CS_ETM_DISCONTINUITY) {
1093 		sample->insn_len = 0;
1094 		return;
1095 	}
1096 
1097 	/*
1098 	 * T32 instruction size might be 32-bit or 16-bit, decide by calling
1099 	 * cs_etm__t32_instr_size().
1100 	 */
1101 	if (packet->isa == CS_ETM_ISA_T32)
1102 		sample->insn_len = cs_etm__t32_instr_size(etmq, trace_chan_id,
1103 							  sample->ip);
1104 	/* Otherwise, A64 and A32 instruction size are always 32-bit. */
1105 	else
1106 		sample->insn_len = 4;
1107 
1108 	cs_etm__mem_access(etmq, trace_chan_id, sample->ip,
1109 			   sample->insn_len, (void *)sample->insn);
1110 }
1111 
1112 static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
1113 					    struct cs_etm_traceid_queue *tidq,
1114 					    u64 addr, u64 period)
1115 {
1116 	int ret = 0;
1117 	struct cs_etm_auxtrace *etm = etmq->etm;
1118 	union perf_event *event = tidq->event_buf;
1119 	struct perf_sample sample = {.ip = 0,};
1120 
1121 	event->sample.header.type = PERF_RECORD_SAMPLE;
1122 	event->sample.header.misc = cs_etm__cpu_mode(etmq, addr);
1123 	event->sample.header.size = sizeof(struct perf_event_header);
1124 
1125 	sample.ip = addr;
1126 	sample.pid = tidq->pid;
1127 	sample.tid = tidq->tid;
1128 	sample.id = etmq->etm->instructions_id;
1129 	sample.stream_id = etmq->etm->instructions_id;
1130 	sample.period = period;
1131 	sample.cpu = tidq->packet->cpu;
1132 	sample.flags = tidq->prev_packet->flags;
1133 	sample.cpumode = event->sample.header.misc;
1134 
1135 	cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->packet, &sample);
1136 
1137 	if (etm->synth_opts.last_branch) {
1138 		cs_etm__copy_last_branch_rb(etmq, tidq);
1139 		sample.branch_stack = tidq->last_branch;
1140 	}
1141 
1142 	if (etm->synth_opts.inject) {
1143 		ret = cs_etm__inject_event(event, &sample,
1144 					   etm->instructions_sample_type);
1145 		if (ret)
1146 			return ret;
1147 	}
1148 
1149 	ret = perf_session__deliver_synth_event(etm->session, event, &sample);
1150 
1151 	if (ret)
1152 		pr_err(
1153 			"CS ETM Trace: failed to deliver instruction event, error %d\n",
1154 			ret);
1155 
1156 	if (etm->synth_opts.last_branch)
1157 		cs_etm__reset_last_branch_rb(tidq);
1158 
1159 	return ret;
1160 }
1161 
1162 /*
1163  * The cs etm packet encodes an instruction range between a branch target
1164  * and the next taken branch. Generate sample accordingly.
1165  */
1166 static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq,
1167 				       struct cs_etm_traceid_queue *tidq)
1168 {
1169 	int ret = 0;
1170 	struct cs_etm_auxtrace *etm = etmq->etm;
1171 	struct perf_sample sample = {.ip = 0,};
1172 	union perf_event *event = tidq->event_buf;
1173 	struct dummy_branch_stack {
1174 		u64			nr;
1175 		struct branch_entry	entries;
1176 	} dummy_bs;
1177 	u64 ip;
1178 
1179 	ip = cs_etm__last_executed_instr(tidq->prev_packet);
1180 
1181 	event->sample.header.type = PERF_RECORD_SAMPLE;
1182 	event->sample.header.misc = cs_etm__cpu_mode(etmq, ip);
1183 	event->sample.header.size = sizeof(struct perf_event_header);
1184 
1185 	sample.ip = ip;
1186 	sample.pid = tidq->pid;
1187 	sample.tid = tidq->tid;
1188 	sample.addr = cs_etm__first_executed_instr(tidq->packet);
1189 	sample.id = etmq->etm->branches_id;
1190 	sample.stream_id = etmq->etm->branches_id;
1191 	sample.period = 1;
1192 	sample.cpu = tidq->packet->cpu;
1193 	sample.flags = tidq->prev_packet->flags;
1194 	sample.cpumode = event->sample.header.misc;
1195 
1196 	cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->prev_packet,
1197 			  &sample);
1198 
1199 	/*
1200 	 * perf report cannot handle events without a branch stack
1201 	 */
1202 	if (etm->synth_opts.last_branch) {
1203 		dummy_bs = (struct dummy_branch_stack){
1204 			.nr = 1,
1205 			.entries = {
1206 				.from = sample.ip,
1207 				.to = sample.addr,
1208 			},
1209 		};
1210 		sample.branch_stack = (struct branch_stack *)&dummy_bs;
1211 	}
1212 
1213 	if (etm->synth_opts.inject) {
1214 		ret = cs_etm__inject_event(event, &sample,
1215 					   etm->branches_sample_type);
1216 		if (ret)
1217 			return ret;
1218 	}
1219 
1220 	ret = perf_session__deliver_synth_event(etm->session, event, &sample);
1221 
1222 	if (ret)
1223 		pr_err(
1224 		"CS ETM Trace: failed to deliver instruction event, error %d\n",
1225 		ret);
1226 
1227 	return ret;
1228 }
1229 
1230 struct cs_etm_synth {
1231 	struct perf_tool dummy_tool;
1232 	struct perf_session *session;
1233 };
1234 
1235 static int cs_etm__event_synth(struct perf_tool *tool,
1236 			       union perf_event *event,
1237 			       struct perf_sample *sample __maybe_unused,
1238 			       struct machine *machine __maybe_unused)
1239 {
1240 	struct cs_etm_synth *cs_etm_synth =
1241 		      container_of(tool, struct cs_etm_synth, dummy_tool);
1242 
1243 	return perf_session__deliver_synth_event(cs_etm_synth->session,
1244 						 event, NULL);
1245 }
1246 
1247 static int cs_etm__synth_event(struct perf_session *session,
1248 			       struct perf_event_attr *attr, u64 id)
1249 {
1250 	struct cs_etm_synth cs_etm_synth;
1251 
1252 	memset(&cs_etm_synth, 0, sizeof(struct cs_etm_synth));
1253 	cs_etm_synth.session = session;
1254 
1255 	return perf_event__synthesize_attr(&cs_etm_synth.dummy_tool, attr, 1,
1256 					   &id, cs_etm__event_synth);
1257 }
1258 
1259 static int cs_etm__synth_events(struct cs_etm_auxtrace *etm,
1260 				struct perf_session *session)
1261 {
1262 	struct evlist *evlist = session->evlist;
1263 	struct evsel *evsel;
1264 	struct perf_event_attr attr;
1265 	bool found = false;
1266 	u64 id;
1267 	int err;
1268 
1269 	evlist__for_each_entry(evlist, evsel) {
1270 		if (evsel->core.attr.type == etm->pmu_type) {
1271 			found = true;
1272 			break;
1273 		}
1274 	}
1275 
1276 	if (!found) {
1277 		pr_debug("No selected events with CoreSight Trace data\n");
1278 		return 0;
1279 	}
1280 
1281 	memset(&attr, 0, sizeof(struct perf_event_attr));
1282 	attr.size = sizeof(struct perf_event_attr);
1283 	attr.type = PERF_TYPE_HARDWARE;
1284 	attr.sample_type = evsel->core.attr.sample_type & PERF_SAMPLE_MASK;
1285 	attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
1286 			    PERF_SAMPLE_PERIOD;
1287 	if (etm->timeless_decoding)
1288 		attr.sample_type &= ~(u64)PERF_SAMPLE_TIME;
1289 	else
1290 		attr.sample_type |= PERF_SAMPLE_TIME;
1291 
1292 	attr.exclude_user = evsel->core.attr.exclude_user;
1293 	attr.exclude_kernel = evsel->core.attr.exclude_kernel;
1294 	attr.exclude_hv = evsel->core.attr.exclude_hv;
1295 	attr.exclude_host = evsel->core.attr.exclude_host;
1296 	attr.exclude_guest = evsel->core.attr.exclude_guest;
1297 	attr.sample_id_all = evsel->core.attr.sample_id_all;
1298 	attr.read_format = evsel->core.attr.read_format;
1299 
1300 	/* create new id val to be a fixed offset from evsel id */
1301 	id = evsel->core.id[0] + 1000000000;
1302 
1303 	if (!id)
1304 		id = 1;
1305 
1306 	if (etm->synth_opts.branches) {
1307 		attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
1308 		attr.sample_period = 1;
1309 		attr.sample_type |= PERF_SAMPLE_ADDR;
1310 		err = cs_etm__synth_event(session, &attr, id);
1311 		if (err)
1312 			return err;
1313 		etm->sample_branches = true;
1314 		etm->branches_sample_type = attr.sample_type;
1315 		etm->branches_id = id;
1316 		id += 1;
1317 		attr.sample_type &= ~(u64)PERF_SAMPLE_ADDR;
1318 	}
1319 
1320 	if (etm->synth_opts.last_branch)
1321 		attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;
1322 
1323 	if (etm->synth_opts.instructions) {
1324 		attr.config = PERF_COUNT_HW_INSTRUCTIONS;
1325 		attr.sample_period = etm->synth_opts.period;
1326 		etm->instructions_sample_period = attr.sample_period;
1327 		err = cs_etm__synth_event(session, &attr, id);
1328 		if (err)
1329 			return err;
1330 		etm->sample_instructions = true;
1331 		etm->instructions_sample_type = attr.sample_type;
1332 		etm->instructions_id = id;
1333 		id += 1;
1334 	}
1335 
1336 	return 0;
1337 }
1338 
1339 static int cs_etm__sample(struct cs_etm_queue *etmq,
1340 			  struct cs_etm_traceid_queue *tidq)
1341 {
1342 	struct cs_etm_auxtrace *etm = etmq->etm;
1343 	struct cs_etm_packet *tmp;
1344 	int ret;
1345 	u8 trace_chan_id = tidq->trace_chan_id;
1346 	u64 instrs_executed = tidq->packet->instr_count;
1347 
1348 	tidq->period_instructions += instrs_executed;
1349 
1350 	/*
1351 	 * Record a branch when the last instruction in
1352 	 * PREV_PACKET is a branch.
1353 	 */
1354 	if (etm->synth_opts.last_branch &&
1355 	    tidq->prev_packet->sample_type == CS_ETM_RANGE &&
1356 	    tidq->prev_packet->last_instr_taken_branch)
1357 		cs_etm__update_last_branch_rb(etmq, tidq);
1358 
1359 	if (etm->sample_instructions &&
1360 	    tidq->period_instructions >= etm->instructions_sample_period) {
1361 		/*
1362 		 * Emit instruction sample periodically
1363 		 * TODO: allow period to be defined in cycles and clock time
1364 		 */
1365 
1366 		/* Get number of instructions executed after the sample point */
1367 		u64 instrs_over = tidq->period_instructions -
1368 			etm->instructions_sample_period;
1369 
1370 		/*
1371 		 * Calculate the address of the sampled instruction (-1 as
1372 		 * sample is reported as though instruction has just been
1373 		 * executed, but PC has not advanced to next instruction)
1374 		 */
1375 		u64 offset = (instrs_executed - instrs_over - 1);
1376 		u64 addr = cs_etm__instr_addr(etmq, trace_chan_id,
1377 					      tidq->packet, offset);
1378 
1379 		ret = cs_etm__synth_instruction_sample(
1380 			etmq, tidq, addr, etm->instructions_sample_period);
1381 		if (ret)
1382 			return ret;
1383 
1384 		/* Carry remaining instructions into next sample period */
1385 		tidq->period_instructions = instrs_over;
1386 	}
1387 
1388 	if (etm->sample_branches) {
1389 		bool generate_sample = false;
1390 
1391 		/* Generate sample for tracing on packet */
1392 		if (tidq->prev_packet->sample_type == CS_ETM_DISCONTINUITY)
1393 			generate_sample = true;
1394 
1395 		/* Generate sample for branch taken packet */
1396 		if (tidq->prev_packet->sample_type == CS_ETM_RANGE &&
1397 		    tidq->prev_packet->last_instr_taken_branch)
1398 			generate_sample = true;
1399 
1400 		if (generate_sample) {
1401 			ret = cs_etm__synth_branch_sample(etmq, tidq);
1402 			if (ret)
1403 				return ret;
1404 		}
1405 	}
1406 
1407 	if (etm->sample_branches || etm->synth_opts.last_branch) {
1408 		/*
1409 		 * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
1410 		 * the next incoming packet.
1411 		 */
1412 		tmp = tidq->packet;
1413 		tidq->packet = tidq->prev_packet;
1414 		tidq->prev_packet = tmp;
1415 	}
1416 
1417 	return 0;
1418 }
1419 
1420 static int cs_etm__exception(struct cs_etm_traceid_queue *tidq)
1421 {
1422 	/*
1423 	 * When the exception packet is inserted, whether the last instruction
1424 	 * in previous range packet is taken branch or not, we need to force
1425 	 * to set 'prev_packet->last_instr_taken_branch' to true.  This ensures
1426 	 * to generate branch sample for the instruction range before the
1427 	 * exception is trapped to kernel or before the exception returning.
1428 	 *
1429 	 * The exception packet includes the dummy address values, so don't
1430 	 * swap PACKET with PREV_PACKET.  This keeps PREV_PACKET to be useful
1431 	 * for generating instruction and branch samples.
1432 	 */
1433 	if (tidq->prev_packet->sample_type == CS_ETM_RANGE)
1434 		tidq->prev_packet->last_instr_taken_branch = true;
1435 
1436 	return 0;
1437 }
1438 
1439 static int cs_etm__flush(struct cs_etm_queue *etmq,
1440 			 struct cs_etm_traceid_queue *tidq)
1441 {
1442 	int err = 0;
1443 	struct cs_etm_auxtrace *etm = etmq->etm;
1444 	struct cs_etm_packet *tmp;
1445 
1446 	/* Handle start tracing packet */
1447 	if (tidq->prev_packet->sample_type == CS_ETM_EMPTY)
1448 		goto swap_packet;
1449 
1450 	if (etmq->etm->synth_opts.last_branch &&
1451 	    tidq->prev_packet->sample_type == CS_ETM_RANGE) {
1452 		/*
1453 		 * Generate a last branch event for the branches left in the
1454 		 * circular buffer at the end of the trace.
1455 		 *
1456 		 * Use the address of the end of the last reported execution
1457 		 * range
1458 		 */
1459 		u64 addr = cs_etm__last_executed_instr(tidq->prev_packet);
1460 
1461 		err = cs_etm__synth_instruction_sample(
1462 			etmq, tidq, addr,
1463 			tidq->period_instructions);
1464 		if (err)
1465 			return err;
1466 
1467 		tidq->period_instructions = 0;
1468 
1469 	}
1470 
1471 	if (etm->sample_branches &&
1472 	    tidq->prev_packet->sample_type == CS_ETM_RANGE) {
1473 		err = cs_etm__synth_branch_sample(etmq, tidq);
1474 		if (err)
1475 			return err;
1476 	}
1477 
1478 swap_packet:
1479 	if (etm->sample_branches || etm->synth_opts.last_branch) {
1480 		/*
1481 		 * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
1482 		 * the next incoming packet.
1483 		 */
1484 		tmp = tidq->packet;
1485 		tidq->packet = tidq->prev_packet;
1486 		tidq->prev_packet = tmp;
1487 	}
1488 
1489 	return err;
1490 }
1491 
1492 static int cs_etm__end_block(struct cs_etm_queue *etmq,
1493 			     struct cs_etm_traceid_queue *tidq)
1494 {
1495 	int err;
1496 
1497 	/*
1498 	 * It has no new packet coming and 'etmq->packet' contains the stale
1499 	 * packet which was set at the previous time with packets swapping;
1500 	 * so skip to generate branch sample to avoid stale packet.
1501 	 *
1502 	 * For this case only flush branch stack and generate a last branch
1503 	 * event for the branches left in the circular buffer at the end of
1504 	 * the trace.
1505 	 */
1506 	if (etmq->etm->synth_opts.last_branch &&
1507 	    tidq->prev_packet->sample_type == CS_ETM_RANGE) {
1508 		/*
1509 		 * Use the address of the end of the last reported execution
1510 		 * range.
1511 		 */
1512 		u64 addr = cs_etm__last_executed_instr(tidq->prev_packet);
1513 
1514 		err = cs_etm__synth_instruction_sample(
1515 			etmq, tidq, addr,
1516 			tidq->period_instructions);
1517 		if (err)
1518 			return err;
1519 
1520 		tidq->period_instructions = 0;
1521 	}
1522 
1523 	return 0;
1524 }
1525 /*
1526  * cs_etm__get_data_block: Fetch a block from the auxtrace_buffer queue
1527  *			   if need be.
1528  * Returns:	< 0	if error
1529  *		= 0	if no more auxtrace_buffer to read
1530  *		> 0	if the current buffer isn't empty yet
1531  */
1532 static int cs_etm__get_data_block(struct cs_etm_queue *etmq)
1533 {
1534 	int ret;
1535 
1536 	if (!etmq->buf_len) {
1537 		ret = cs_etm__get_trace(etmq);
1538 		if (ret <= 0)
1539 			return ret;
1540 		/*
1541 		 * We cannot assume consecutive blocks in the data file
1542 		 * are contiguous, reset the decoder to force re-sync.
1543 		 */
1544 		ret = cs_etm_decoder__reset(etmq->decoder);
1545 		if (ret)
1546 			return ret;
1547 	}
1548 
1549 	return etmq->buf_len;
1550 }
1551 
1552 static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq, u8 trace_chan_id,
1553 				 struct cs_etm_packet *packet,
1554 				 u64 end_addr)
1555 {
1556 	/* Initialise to keep compiler happy */
1557 	u16 instr16 = 0;
1558 	u32 instr32 = 0;
1559 	u64 addr;
1560 
1561 	switch (packet->isa) {
1562 	case CS_ETM_ISA_T32:
1563 		/*
1564 		 * The SVC of T32 is defined in ARM DDI 0487D.a, F5.1.247:
1565 		 *
1566 		 *  b'15         b'8
1567 		 * +-----------------+--------+
1568 		 * | 1 1 0 1 1 1 1 1 |  imm8  |
1569 		 * +-----------------+--------+
1570 		 *
1571 		 * According to the specifiction, it only defines SVC for T32
1572 		 * with 16 bits instruction and has no definition for 32bits;
1573 		 * so below only read 2 bytes as instruction size for T32.
1574 		 */
1575 		addr = end_addr - 2;
1576 		cs_etm__mem_access(etmq, trace_chan_id, addr,
1577 				   sizeof(instr16), (u8 *)&instr16);
1578 		if ((instr16 & 0xFF00) == 0xDF00)
1579 			return true;
1580 
1581 		break;
1582 	case CS_ETM_ISA_A32:
1583 		/*
1584 		 * The SVC of A32 is defined in ARM DDI 0487D.a, F5.1.247:
1585 		 *
1586 		 *  b'31 b'28 b'27 b'24
1587 		 * +---------+---------+-------------------------+
1588 		 * |  !1111  | 1 1 1 1 |        imm24            |
1589 		 * +---------+---------+-------------------------+
1590 		 */
1591 		addr = end_addr - 4;
1592 		cs_etm__mem_access(etmq, trace_chan_id, addr,
1593 				   sizeof(instr32), (u8 *)&instr32);
1594 		if ((instr32 & 0x0F000000) == 0x0F000000 &&
1595 		    (instr32 & 0xF0000000) != 0xF0000000)
1596 			return true;
1597 
1598 		break;
1599 	case CS_ETM_ISA_A64:
1600 		/*
1601 		 * The SVC of A64 is defined in ARM DDI 0487D.a, C6.2.294:
1602 		 *
1603 		 *  b'31               b'21           b'4     b'0
1604 		 * +-----------------------+---------+-----------+
1605 		 * | 1 1 0 1 0 1 0 0 0 0 0 |  imm16  | 0 0 0 0 1 |
1606 		 * +-----------------------+---------+-----------+
1607 		 */
1608 		addr = end_addr - 4;
1609 		cs_etm__mem_access(etmq, trace_chan_id, addr,
1610 				   sizeof(instr32), (u8 *)&instr32);
1611 		if ((instr32 & 0xFFE0001F) == 0xd4000001)
1612 			return true;
1613 
1614 		break;
1615 	case CS_ETM_ISA_UNKNOWN:
1616 	default:
1617 		break;
1618 	}
1619 
1620 	return false;
1621 }
1622 
1623 static bool cs_etm__is_syscall(struct cs_etm_queue *etmq,
1624 			       struct cs_etm_traceid_queue *tidq, u64 magic)
1625 {
1626 	u8 trace_chan_id = tidq->trace_chan_id;
1627 	struct cs_etm_packet *packet = tidq->packet;
1628 	struct cs_etm_packet *prev_packet = tidq->prev_packet;
1629 
1630 	if (magic == __perf_cs_etmv3_magic)
1631 		if (packet->exception_number == CS_ETMV3_EXC_SVC)
1632 			return true;
1633 
1634 	/*
1635 	 * ETMv4 exception type CS_ETMV4_EXC_CALL covers SVC, SMC and
1636 	 * HVC cases; need to check if it's SVC instruction based on
1637 	 * packet address.
1638 	 */
1639 	if (magic == __perf_cs_etmv4_magic) {
1640 		if (packet->exception_number == CS_ETMV4_EXC_CALL &&
1641 		    cs_etm__is_svc_instr(etmq, trace_chan_id, prev_packet,
1642 					 prev_packet->end_addr))
1643 			return true;
1644 	}
1645 
1646 	return false;
1647 }
1648 
1649 static bool cs_etm__is_async_exception(struct cs_etm_traceid_queue *tidq,
1650 				       u64 magic)
1651 {
1652 	struct cs_etm_packet *packet = tidq->packet;
1653 
1654 	if (magic == __perf_cs_etmv3_magic)
1655 		if (packet->exception_number == CS_ETMV3_EXC_DEBUG_HALT ||
1656 		    packet->exception_number == CS_ETMV3_EXC_ASYNC_DATA_ABORT ||
1657 		    packet->exception_number == CS_ETMV3_EXC_PE_RESET ||
1658 		    packet->exception_number == CS_ETMV3_EXC_IRQ ||
1659 		    packet->exception_number == CS_ETMV3_EXC_FIQ)
1660 			return true;
1661 
1662 	if (magic == __perf_cs_etmv4_magic)
1663 		if (packet->exception_number == CS_ETMV4_EXC_RESET ||
1664 		    packet->exception_number == CS_ETMV4_EXC_DEBUG_HALT ||
1665 		    packet->exception_number == CS_ETMV4_EXC_SYSTEM_ERROR ||
1666 		    packet->exception_number == CS_ETMV4_EXC_INST_DEBUG ||
1667 		    packet->exception_number == CS_ETMV4_EXC_DATA_DEBUG ||
1668 		    packet->exception_number == CS_ETMV4_EXC_IRQ ||
1669 		    packet->exception_number == CS_ETMV4_EXC_FIQ)
1670 			return true;
1671 
1672 	return false;
1673 }
1674 
1675 static bool cs_etm__is_sync_exception(struct cs_etm_queue *etmq,
1676 				      struct cs_etm_traceid_queue *tidq,
1677 				      u64 magic)
1678 {
1679 	u8 trace_chan_id = tidq->trace_chan_id;
1680 	struct cs_etm_packet *packet = tidq->packet;
1681 	struct cs_etm_packet *prev_packet = tidq->prev_packet;
1682 
1683 	if (magic == __perf_cs_etmv3_magic)
1684 		if (packet->exception_number == CS_ETMV3_EXC_SMC ||
1685 		    packet->exception_number == CS_ETMV3_EXC_HYP ||
1686 		    packet->exception_number == CS_ETMV3_EXC_JAZELLE_THUMBEE ||
1687 		    packet->exception_number == CS_ETMV3_EXC_UNDEFINED_INSTR ||
1688 		    packet->exception_number == CS_ETMV3_EXC_PREFETCH_ABORT ||
1689 		    packet->exception_number == CS_ETMV3_EXC_DATA_FAULT ||
1690 		    packet->exception_number == CS_ETMV3_EXC_GENERIC)
1691 			return true;
1692 
1693 	if (magic == __perf_cs_etmv4_magic) {
1694 		if (packet->exception_number == CS_ETMV4_EXC_TRAP ||
1695 		    packet->exception_number == CS_ETMV4_EXC_ALIGNMENT ||
1696 		    packet->exception_number == CS_ETMV4_EXC_INST_FAULT ||
1697 		    packet->exception_number == CS_ETMV4_EXC_DATA_FAULT)
1698 			return true;
1699 
1700 		/*
1701 		 * For CS_ETMV4_EXC_CALL, except SVC other instructions
1702 		 * (SMC, HVC) are taken as sync exceptions.
1703 		 */
1704 		if (packet->exception_number == CS_ETMV4_EXC_CALL &&
1705 		    !cs_etm__is_svc_instr(etmq, trace_chan_id, prev_packet,
1706 					  prev_packet->end_addr))
1707 			return true;
1708 
1709 		/*
1710 		 * ETMv4 has 5 bits for exception number; if the numbers
1711 		 * are in the range ( CS_ETMV4_EXC_FIQ, CS_ETMV4_EXC_END ]
1712 		 * they are implementation defined exceptions.
1713 		 *
1714 		 * For this case, simply take it as sync exception.
1715 		 */
1716 		if (packet->exception_number > CS_ETMV4_EXC_FIQ &&
1717 		    packet->exception_number <= CS_ETMV4_EXC_END)
1718 			return true;
1719 	}
1720 
1721 	return false;
1722 }
1723 
1724 static int cs_etm__set_sample_flags(struct cs_etm_queue *etmq,
1725 				    struct cs_etm_traceid_queue *tidq)
1726 {
1727 	struct cs_etm_packet *packet = tidq->packet;
1728 	struct cs_etm_packet *prev_packet = tidq->prev_packet;
1729 	u8 trace_chan_id = tidq->trace_chan_id;
1730 	u64 magic;
1731 	int ret;
1732 
1733 	switch (packet->sample_type) {
1734 	case CS_ETM_RANGE:
1735 		/*
1736 		 * Immediate branch instruction without neither link nor
1737 		 * return flag, it's normal branch instruction within
1738 		 * the function.
1739 		 */
1740 		if (packet->last_instr_type == OCSD_INSTR_BR &&
1741 		    packet->last_instr_subtype == OCSD_S_INSTR_NONE) {
1742 			packet->flags = PERF_IP_FLAG_BRANCH;
1743 
1744 			if (packet->last_instr_cond)
1745 				packet->flags |= PERF_IP_FLAG_CONDITIONAL;
1746 		}
1747 
1748 		/*
1749 		 * Immediate branch instruction with link (e.g. BL), this is
1750 		 * branch instruction for function call.
1751 		 */
1752 		if (packet->last_instr_type == OCSD_INSTR_BR &&
1753 		    packet->last_instr_subtype == OCSD_S_INSTR_BR_LINK)
1754 			packet->flags = PERF_IP_FLAG_BRANCH |
1755 					PERF_IP_FLAG_CALL;
1756 
1757 		/*
1758 		 * Indirect branch instruction with link (e.g. BLR), this is
1759 		 * branch instruction for function call.
1760 		 */
1761 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1762 		    packet->last_instr_subtype == OCSD_S_INSTR_BR_LINK)
1763 			packet->flags = PERF_IP_FLAG_BRANCH |
1764 					PERF_IP_FLAG_CALL;
1765 
1766 		/*
1767 		 * Indirect branch instruction with subtype of
1768 		 * OCSD_S_INSTR_V7_IMPLIED_RET, this is explicit hint for
1769 		 * function return for A32/T32.
1770 		 */
1771 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1772 		    packet->last_instr_subtype == OCSD_S_INSTR_V7_IMPLIED_RET)
1773 			packet->flags = PERF_IP_FLAG_BRANCH |
1774 					PERF_IP_FLAG_RETURN;
1775 
1776 		/*
1777 		 * Indirect branch instruction without link (e.g. BR), usually
1778 		 * this is used for function return, especially for functions
1779 		 * within dynamic link lib.
1780 		 */
1781 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1782 		    packet->last_instr_subtype == OCSD_S_INSTR_NONE)
1783 			packet->flags = PERF_IP_FLAG_BRANCH |
1784 					PERF_IP_FLAG_RETURN;
1785 
1786 		/* Return instruction for function return. */
1787 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1788 		    packet->last_instr_subtype == OCSD_S_INSTR_V8_RET)
1789 			packet->flags = PERF_IP_FLAG_BRANCH |
1790 					PERF_IP_FLAG_RETURN;
1791 
1792 		/*
1793 		 * Decoder might insert a discontinuity in the middle of
1794 		 * instruction packets, fixup prev_packet with flag
1795 		 * PERF_IP_FLAG_TRACE_BEGIN to indicate restarting trace.
1796 		 */
1797 		if (prev_packet->sample_type == CS_ETM_DISCONTINUITY)
1798 			prev_packet->flags |= PERF_IP_FLAG_BRANCH |
1799 					      PERF_IP_FLAG_TRACE_BEGIN;
1800 
1801 		/*
1802 		 * If the previous packet is an exception return packet
1803 		 * and the return address just follows SVC instuction,
1804 		 * it needs to calibrate the previous packet sample flags
1805 		 * as PERF_IP_FLAG_SYSCALLRET.
1806 		 */
1807 		if (prev_packet->flags == (PERF_IP_FLAG_BRANCH |
1808 					   PERF_IP_FLAG_RETURN |
1809 					   PERF_IP_FLAG_INTERRUPT) &&
1810 		    cs_etm__is_svc_instr(etmq, trace_chan_id,
1811 					 packet, packet->start_addr))
1812 			prev_packet->flags = PERF_IP_FLAG_BRANCH |
1813 					     PERF_IP_FLAG_RETURN |
1814 					     PERF_IP_FLAG_SYSCALLRET;
1815 		break;
1816 	case CS_ETM_DISCONTINUITY:
1817 		/*
1818 		 * The trace is discontinuous, if the previous packet is
1819 		 * instruction packet, set flag PERF_IP_FLAG_TRACE_END
1820 		 * for previous packet.
1821 		 */
1822 		if (prev_packet->sample_type == CS_ETM_RANGE)
1823 			prev_packet->flags |= PERF_IP_FLAG_BRANCH |
1824 					      PERF_IP_FLAG_TRACE_END;
1825 		break;
1826 	case CS_ETM_EXCEPTION:
1827 		ret = cs_etm__get_magic(packet->trace_chan_id, &magic);
1828 		if (ret)
1829 			return ret;
1830 
1831 		/* The exception is for system call. */
1832 		if (cs_etm__is_syscall(etmq, tidq, magic))
1833 			packet->flags = PERF_IP_FLAG_BRANCH |
1834 					PERF_IP_FLAG_CALL |
1835 					PERF_IP_FLAG_SYSCALLRET;
1836 		/*
1837 		 * The exceptions are triggered by external signals from bus,
1838 		 * interrupt controller, debug module, PE reset or halt.
1839 		 */
1840 		else if (cs_etm__is_async_exception(tidq, magic))
1841 			packet->flags = PERF_IP_FLAG_BRANCH |
1842 					PERF_IP_FLAG_CALL |
1843 					PERF_IP_FLAG_ASYNC |
1844 					PERF_IP_FLAG_INTERRUPT;
1845 		/*
1846 		 * Otherwise, exception is caused by trap, instruction &
1847 		 * data fault, or alignment errors.
1848 		 */
1849 		else if (cs_etm__is_sync_exception(etmq, tidq, magic))
1850 			packet->flags = PERF_IP_FLAG_BRANCH |
1851 					PERF_IP_FLAG_CALL |
1852 					PERF_IP_FLAG_INTERRUPT;
1853 
1854 		/*
1855 		 * When the exception packet is inserted, since exception
1856 		 * packet is not used standalone for generating samples
1857 		 * and it's affiliation to the previous instruction range
1858 		 * packet; so set previous range packet flags to tell perf
1859 		 * it is an exception taken branch.
1860 		 */
1861 		if (prev_packet->sample_type == CS_ETM_RANGE)
1862 			prev_packet->flags = packet->flags;
1863 		break;
1864 	case CS_ETM_EXCEPTION_RET:
1865 		/*
1866 		 * When the exception return packet is inserted, since
1867 		 * exception return packet is not used standalone for
1868 		 * generating samples and it's affiliation to the previous
1869 		 * instruction range packet; so set previous range packet
1870 		 * flags to tell perf it is an exception return branch.
1871 		 *
1872 		 * The exception return can be for either system call or
1873 		 * other exception types; unfortunately the packet doesn't
1874 		 * contain exception type related info so we cannot decide
1875 		 * the exception type purely based on exception return packet.
1876 		 * If we record the exception number from exception packet and
1877 		 * reuse it for excpetion return packet, this is not reliable
1878 		 * due the trace can be discontinuity or the interrupt can
1879 		 * be nested, thus the recorded exception number cannot be
1880 		 * used for exception return packet for these two cases.
1881 		 *
1882 		 * For exception return packet, we only need to distinguish the
1883 		 * packet is for system call or for other types.  Thus the
1884 		 * decision can be deferred when receive the next packet which
1885 		 * contains the return address, based on the return address we
1886 		 * can read out the previous instruction and check if it's a
1887 		 * system call instruction and then calibrate the sample flag
1888 		 * as needed.
1889 		 */
1890 		if (prev_packet->sample_type == CS_ETM_RANGE)
1891 			prev_packet->flags = PERF_IP_FLAG_BRANCH |
1892 					     PERF_IP_FLAG_RETURN |
1893 					     PERF_IP_FLAG_INTERRUPT;
1894 		break;
1895 	case CS_ETM_EMPTY:
1896 	default:
1897 		break;
1898 	}
1899 
1900 	return 0;
1901 }
1902 
1903 static int cs_etm__decode_data_block(struct cs_etm_queue *etmq)
1904 {
1905 	int ret = 0;
1906 	size_t processed = 0;
1907 
1908 	/*
1909 	 * Packets are decoded and added to the decoder's packet queue
1910 	 * until the decoder packet processing callback has requested that
1911 	 * processing stops or there is nothing left in the buffer.  Normal
1912 	 * operations that stop processing are a timestamp packet or a full
1913 	 * decoder buffer queue.
1914 	 */
1915 	ret = cs_etm_decoder__process_data_block(etmq->decoder,
1916 						 etmq->offset,
1917 						 &etmq->buf[etmq->buf_used],
1918 						 etmq->buf_len,
1919 						 &processed);
1920 	if (ret)
1921 		goto out;
1922 
1923 	etmq->offset += processed;
1924 	etmq->buf_used += processed;
1925 	etmq->buf_len -= processed;
1926 
1927 out:
1928 	return ret;
1929 }
1930 
1931 static int cs_etm__process_traceid_queue(struct cs_etm_queue *etmq,
1932 					 struct cs_etm_traceid_queue *tidq)
1933 {
1934 	int ret;
1935 	struct cs_etm_packet_queue *packet_queue;
1936 
1937 	packet_queue = &tidq->packet_queue;
1938 
1939 	/* Process each packet in this chunk */
1940 	while (1) {
1941 		ret = cs_etm_decoder__get_packet(packet_queue,
1942 						 tidq->packet);
1943 		if (ret <= 0)
1944 			/*
1945 			 * Stop processing this chunk on
1946 			 * end of data or error
1947 			 */
1948 			break;
1949 
1950 		/*
1951 		 * Since packet addresses are swapped in packet
1952 		 * handling within below switch() statements,
1953 		 * thus setting sample flags must be called
1954 		 * prior to switch() statement to use address
1955 		 * information before packets swapping.
1956 		 */
1957 		ret = cs_etm__set_sample_flags(etmq, tidq);
1958 		if (ret < 0)
1959 			break;
1960 
1961 		switch (tidq->packet->sample_type) {
1962 		case CS_ETM_RANGE:
1963 			/*
1964 			 * If the packet contains an instruction
1965 			 * range, generate instruction sequence
1966 			 * events.
1967 			 */
1968 			cs_etm__sample(etmq, tidq);
1969 			break;
1970 		case CS_ETM_EXCEPTION:
1971 		case CS_ETM_EXCEPTION_RET:
1972 			/*
1973 			 * If the exception packet is coming,
1974 			 * make sure the previous instruction
1975 			 * range packet to be handled properly.
1976 			 */
1977 			cs_etm__exception(tidq);
1978 			break;
1979 		case CS_ETM_DISCONTINUITY:
1980 			/*
1981 			 * Discontinuity in trace, flush
1982 			 * previous branch stack
1983 			 */
1984 			cs_etm__flush(etmq, tidq);
1985 			break;
1986 		case CS_ETM_EMPTY:
1987 			/*
1988 			 * Should not receive empty packet,
1989 			 * report error.
1990 			 */
1991 			pr_err("CS ETM Trace: empty packet\n");
1992 			return -EINVAL;
1993 		default:
1994 			break;
1995 		}
1996 	}
1997 
1998 	return ret;
1999 }
2000 
2001 static void cs_etm__clear_all_traceid_queues(struct cs_etm_queue *etmq)
2002 {
2003 	int idx;
2004 	struct int_node *inode;
2005 	struct cs_etm_traceid_queue *tidq;
2006 	struct intlist *traceid_queues_list = etmq->traceid_queues_list;
2007 
2008 	intlist__for_each_entry(inode, traceid_queues_list) {
2009 		idx = (int)(intptr_t)inode->priv;
2010 		tidq = etmq->traceid_queues[idx];
2011 
2012 		/* Ignore return value */
2013 		cs_etm__process_traceid_queue(etmq, tidq);
2014 
2015 		/*
2016 		 * Generate an instruction sample with the remaining
2017 		 * branchstack entries.
2018 		 */
2019 		cs_etm__flush(etmq, tidq);
2020 	}
2021 }
2022 
2023 static int cs_etm__run_decoder(struct cs_etm_queue *etmq)
2024 {
2025 	int err = 0;
2026 	struct cs_etm_traceid_queue *tidq;
2027 
2028 	tidq = cs_etm__etmq_get_traceid_queue(etmq, CS_ETM_PER_THREAD_TRACEID);
2029 	if (!tidq)
2030 		return -EINVAL;
2031 
2032 	/* Go through each buffer in the queue and decode them one by one */
2033 	while (1) {
2034 		err = cs_etm__get_data_block(etmq);
2035 		if (err <= 0)
2036 			return err;
2037 
2038 		/* Run trace decoder until buffer consumed or end of trace */
2039 		do {
2040 			err = cs_etm__decode_data_block(etmq);
2041 			if (err)
2042 				return err;
2043 
2044 			/*
2045 			 * Process each packet in this chunk, nothing to do if
2046 			 * an error occurs other than hoping the next one will
2047 			 * be better.
2048 			 */
2049 			err = cs_etm__process_traceid_queue(etmq, tidq);
2050 
2051 		} while (etmq->buf_len);
2052 
2053 		if (err == 0)
2054 			/* Flush any remaining branch stack entries */
2055 			err = cs_etm__end_block(etmq, tidq);
2056 	}
2057 
2058 	return err;
2059 }
2060 
2061 static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
2062 					   pid_t tid)
2063 {
2064 	unsigned int i;
2065 	struct auxtrace_queues *queues = &etm->queues;
2066 
2067 	for (i = 0; i < queues->nr_queues; i++) {
2068 		struct auxtrace_queue *queue = &etm->queues.queue_array[i];
2069 		struct cs_etm_queue *etmq = queue->priv;
2070 		struct cs_etm_traceid_queue *tidq;
2071 
2072 		if (!etmq)
2073 			continue;
2074 
2075 		tidq = cs_etm__etmq_get_traceid_queue(etmq,
2076 						CS_ETM_PER_THREAD_TRACEID);
2077 
2078 		if (!tidq)
2079 			continue;
2080 
2081 		if ((tid == -1) || (tidq->tid == tid)) {
2082 			cs_etm__set_pid_tid_cpu(etm, tidq);
2083 			cs_etm__run_decoder(etmq);
2084 		}
2085 	}
2086 
2087 	return 0;
2088 }
2089 
2090 static int cs_etm__process_queues(struct cs_etm_auxtrace *etm)
2091 {
2092 	int ret = 0;
2093 	unsigned int cs_queue_nr, queue_nr;
2094 	u8 trace_chan_id;
2095 	u64 timestamp;
2096 	struct auxtrace_queue *queue;
2097 	struct cs_etm_queue *etmq;
2098 	struct cs_etm_traceid_queue *tidq;
2099 
2100 	while (1) {
2101 		if (!etm->heap.heap_cnt)
2102 			goto out;
2103 
2104 		/* Take the entry at the top of the min heap */
2105 		cs_queue_nr = etm->heap.heap_array[0].queue_nr;
2106 		queue_nr = TO_QUEUE_NR(cs_queue_nr);
2107 		trace_chan_id = TO_TRACE_CHAN_ID(cs_queue_nr);
2108 		queue = &etm->queues.queue_array[queue_nr];
2109 		etmq = queue->priv;
2110 
2111 		/*
2112 		 * Remove the top entry from the heap since we are about
2113 		 * to process it.
2114 		 */
2115 		auxtrace_heap__pop(&etm->heap);
2116 
2117 		tidq  = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
2118 		if (!tidq) {
2119 			/*
2120 			 * No traceID queue has been allocated for this traceID,
2121 			 * which means something somewhere went very wrong.  No
2122 			 * other choice than simply exit.
2123 			 */
2124 			ret = -EINVAL;
2125 			goto out;
2126 		}
2127 
2128 		/*
2129 		 * Packets associated with this timestamp are already in
2130 		 * the etmq's traceID queue, so process them.
2131 		 */
2132 		ret = cs_etm__process_traceid_queue(etmq, tidq);
2133 		if (ret < 0)
2134 			goto out;
2135 
2136 		/*
2137 		 * Packets for this timestamp have been processed, time to
2138 		 * move on to the next timestamp, fetching a new auxtrace_buffer
2139 		 * if need be.
2140 		 */
2141 refetch:
2142 		ret = cs_etm__get_data_block(etmq);
2143 		if (ret < 0)
2144 			goto out;
2145 
2146 		/*
2147 		 * No more auxtrace_buffers to process in this etmq, simply
2148 		 * move on to another entry in the auxtrace_heap.
2149 		 */
2150 		if (!ret)
2151 			continue;
2152 
2153 		ret = cs_etm__decode_data_block(etmq);
2154 		if (ret)
2155 			goto out;
2156 
2157 		timestamp = cs_etm__etmq_get_timestamp(etmq, &trace_chan_id);
2158 
2159 		if (!timestamp) {
2160 			/*
2161 			 * Function cs_etm__decode_data_block() returns when
2162 			 * there is no more traces to decode in the current
2163 			 * auxtrace_buffer OR when a timestamp has been
2164 			 * encountered on any of the traceID queues.  Since we
2165 			 * did not get a timestamp, there is no more traces to
2166 			 * process in this auxtrace_buffer.  As such empty and
2167 			 * flush all traceID queues.
2168 			 */
2169 			cs_etm__clear_all_traceid_queues(etmq);
2170 
2171 			/* Fetch another auxtrace_buffer for this etmq */
2172 			goto refetch;
2173 		}
2174 
2175 		/*
2176 		 * Add to the min heap the timestamp for packets that have
2177 		 * just been decoded.  They will be processed and synthesized
2178 		 * during the next call to cs_etm__process_traceid_queue() for
2179 		 * this queue/traceID.
2180 		 */
2181 		cs_queue_nr = TO_CS_QUEUE_NR(queue_nr, trace_chan_id);
2182 		ret = auxtrace_heap__add(&etm->heap, cs_queue_nr, timestamp);
2183 	}
2184 
2185 out:
2186 	return ret;
2187 }
2188 
2189 static int cs_etm__process_itrace_start(struct cs_etm_auxtrace *etm,
2190 					union perf_event *event)
2191 {
2192 	struct thread *th;
2193 
2194 	if (etm->timeless_decoding)
2195 		return 0;
2196 
2197 	/*
2198 	 * Add the tid/pid to the log so that we can get a match when
2199 	 * we get a contextID from the decoder.
2200 	 */
2201 	th = machine__findnew_thread(etm->machine,
2202 				     event->itrace_start.pid,
2203 				     event->itrace_start.tid);
2204 	if (!th)
2205 		return -ENOMEM;
2206 
2207 	thread__put(th);
2208 
2209 	return 0;
2210 }
2211 
2212 static int cs_etm__process_switch_cpu_wide(struct cs_etm_auxtrace *etm,
2213 					   union perf_event *event)
2214 {
2215 	struct thread *th;
2216 	bool out = event->header.misc & PERF_RECORD_MISC_SWITCH_OUT;
2217 
2218 	/*
2219 	 * Context switch in per-thread mode are irrelevant since perf
2220 	 * will start/stop tracing as the process is scheduled.
2221 	 */
2222 	if (etm->timeless_decoding)
2223 		return 0;
2224 
2225 	/*
2226 	 * SWITCH_IN events carry the next process to be switched out while
2227 	 * SWITCH_OUT events carry the process to be switched in.  As such
2228 	 * we don't care about IN events.
2229 	 */
2230 	if (!out)
2231 		return 0;
2232 
2233 	/*
2234 	 * Add the tid/pid to the log so that we can get a match when
2235 	 * we get a contextID from the decoder.
2236 	 */
2237 	th = machine__findnew_thread(etm->machine,
2238 				     event->context_switch.next_prev_pid,
2239 				     event->context_switch.next_prev_tid);
2240 	if (!th)
2241 		return -ENOMEM;
2242 
2243 	thread__put(th);
2244 
2245 	return 0;
2246 }
2247 
2248 static int cs_etm__process_event(struct perf_session *session,
2249 				 union perf_event *event,
2250 				 struct perf_sample *sample,
2251 				 struct perf_tool *tool)
2252 {
2253 	int err = 0;
2254 	u64 timestamp;
2255 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
2256 						   struct cs_etm_auxtrace,
2257 						   auxtrace);
2258 
2259 	if (dump_trace)
2260 		return 0;
2261 
2262 	if (!tool->ordered_events) {
2263 		pr_err("CoreSight ETM Trace requires ordered events\n");
2264 		return -EINVAL;
2265 	}
2266 
2267 	if (sample->time && (sample->time != (u64) -1))
2268 		timestamp = sample->time;
2269 	else
2270 		timestamp = 0;
2271 
2272 	if (timestamp || etm->timeless_decoding) {
2273 		err = cs_etm__update_queues(etm);
2274 		if (err)
2275 			return err;
2276 	}
2277 
2278 	if (etm->timeless_decoding &&
2279 	    event->header.type == PERF_RECORD_EXIT)
2280 		return cs_etm__process_timeless_queues(etm,
2281 						       event->fork.tid);
2282 
2283 	if (event->header.type == PERF_RECORD_ITRACE_START)
2284 		return cs_etm__process_itrace_start(etm, event);
2285 	else if (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE)
2286 		return cs_etm__process_switch_cpu_wide(etm, event);
2287 
2288 	if (!etm->timeless_decoding &&
2289 	    event->header.type == PERF_RECORD_AUX)
2290 		return cs_etm__process_queues(etm);
2291 
2292 	return 0;
2293 }
2294 
2295 static int cs_etm__process_auxtrace_event(struct perf_session *session,
2296 					  union perf_event *event,
2297 					  struct perf_tool *tool __maybe_unused)
2298 {
2299 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
2300 						   struct cs_etm_auxtrace,
2301 						   auxtrace);
2302 	if (!etm->data_queued) {
2303 		struct auxtrace_buffer *buffer;
2304 		off_t  data_offset;
2305 		int fd = perf_data__fd(session->data);
2306 		bool is_pipe = perf_data__is_pipe(session->data);
2307 		int err;
2308 
2309 		if (is_pipe)
2310 			data_offset = 0;
2311 		else {
2312 			data_offset = lseek(fd, 0, SEEK_CUR);
2313 			if (data_offset == -1)
2314 				return -errno;
2315 		}
2316 
2317 		err = auxtrace_queues__add_event(&etm->queues, session,
2318 						 event, data_offset, &buffer);
2319 		if (err)
2320 			return err;
2321 
2322 		if (dump_trace)
2323 			if (auxtrace_buffer__get_data(buffer, fd)) {
2324 				cs_etm__dump_event(etm, buffer);
2325 				auxtrace_buffer__put_data(buffer);
2326 			}
2327 	}
2328 
2329 	return 0;
2330 }
2331 
2332 static bool cs_etm__is_timeless_decoding(struct cs_etm_auxtrace *etm)
2333 {
2334 	struct evsel *evsel;
2335 	struct evlist *evlist = etm->session->evlist;
2336 	bool timeless_decoding = true;
2337 
2338 	/*
2339 	 * Circle through the list of event and complain if we find one
2340 	 * with the time bit set.
2341 	 */
2342 	evlist__for_each_entry(evlist, evsel) {
2343 		if ((evsel->core.attr.sample_type & PERF_SAMPLE_TIME))
2344 			timeless_decoding = false;
2345 	}
2346 
2347 	return timeless_decoding;
2348 }
2349 
2350 static const char * const cs_etm_global_header_fmts[] = {
2351 	[CS_HEADER_VERSION_0]	= "	Header version		       %llx\n",
2352 	[CS_PMU_TYPE_CPUS]	= "	PMU type/num cpus	       %llx\n",
2353 	[CS_ETM_SNAPSHOT]	= "	Snapshot		       %llx\n",
2354 };
2355 
2356 static const char * const cs_etm_priv_fmts[] = {
2357 	[CS_ETM_MAGIC]		= "	Magic number		       %llx\n",
2358 	[CS_ETM_CPU]		= "	CPU			       %lld\n",
2359 	[CS_ETM_ETMCR]		= "	ETMCR			       %llx\n",
2360 	[CS_ETM_ETMTRACEIDR]	= "	ETMTRACEIDR		       %llx\n",
2361 	[CS_ETM_ETMCCER]	= "	ETMCCER			       %llx\n",
2362 	[CS_ETM_ETMIDR]		= "	ETMIDR			       %llx\n",
2363 };
2364 
2365 static const char * const cs_etmv4_priv_fmts[] = {
2366 	[CS_ETM_MAGIC]		= "	Magic number		       %llx\n",
2367 	[CS_ETM_CPU]		= "	CPU			       %lld\n",
2368 	[CS_ETMV4_TRCCONFIGR]	= "	TRCCONFIGR		       %llx\n",
2369 	[CS_ETMV4_TRCTRACEIDR]	= "	TRCTRACEIDR		       %llx\n",
2370 	[CS_ETMV4_TRCIDR0]	= "	TRCIDR0			       %llx\n",
2371 	[CS_ETMV4_TRCIDR1]	= "	TRCIDR1			       %llx\n",
2372 	[CS_ETMV4_TRCIDR2]	= "	TRCIDR2			       %llx\n",
2373 	[CS_ETMV4_TRCIDR8]	= "	TRCIDR8			       %llx\n",
2374 	[CS_ETMV4_TRCAUTHSTATUS] = "	TRCAUTHSTATUS		       %llx\n",
2375 };
2376 
2377 static void cs_etm__print_auxtrace_info(__u64 *val, int num)
2378 {
2379 	int i, j, cpu = 0;
2380 
2381 	for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
2382 		fprintf(stdout, cs_etm_global_header_fmts[i], val[i]);
2383 
2384 	for (i = CS_HEADER_VERSION_0_MAX; cpu < num; cpu++) {
2385 		if (val[i] == __perf_cs_etmv3_magic)
2386 			for (j = 0; j < CS_ETM_PRIV_MAX; j++, i++)
2387 				fprintf(stdout, cs_etm_priv_fmts[j], val[i]);
2388 		else if (val[i] == __perf_cs_etmv4_magic)
2389 			for (j = 0; j < CS_ETMV4_PRIV_MAX; j++, i++)
2390 				fprintf(stdout, cs_etmv4_priv_fmts[j], val[i]);
2391 		else
2392 			/* failure.. return */
2393 			return;
2394 	}
2395 }
2396 
2397 int cs_etm__process_auxtrace_info(union perf_event *event,
2398 				  struct perf_session *session)
2399 {
2400 	struct perf_record_auxtrace_info *auxtrace_info = &event->auxtrace_info;
2401 	struct cs_etm_auxtrace *etm = NULL;
2402 	struct int_node *inode;
2403 	unsigned int pmu_type;
2404 	int event_header_size = sizeof(struct perf_event_header);
2405 	int info_header_size;
2406 	int total_size = auxtrace_info->header.size;
2407 	int priv_size = 0;
2408 	int num_cpu;
2409 	int err = 0, idx = -1;
2410 	int i, j, k;
2411 	u64 *ptr, *hdr = NULL;
2412 	u64 **metadata = NULL;
2413 
2414 	/*
2415 	 * sizeof(auxtrace_info_event::type) +
2416 	 * sizeof(auxtrace_info_event::reserved) == 8
2417 	 */
2418 	info_header_size = 8;
2419 
2420 	if (total_size < (event_header_size + info_header_size))
2421 		return -EINVAL;
2422 
2423 	priv_size = total_size - event_header_size - info_header_size;
2424 
2425 	/* First the global part */
2426 	ptr = (u64 *) auxtrace_info->priv;
2427 
2428 	/* Look for version '0' of the header */
2429 	if (ptr[0] != 0)
2430 		return -EINVAL;
2431 
2432 	hdr = zalloc(sizeof(*hdr) * CS_HEADER_VERSION_0_MAX);
2433 	if (!hdr)
2434 		return -ENOMEM;
2435 
2436 	/* Extract header information - see cs-etm.h for format */
2437 	for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
2438 		hdr[i] = ptr[i];
2439 	num_cpu = hdr[CS_PMU_TYPE_CPUS] & 0xffffffff;
2440 	pmu_type = (unsigned int) ((hdr[CS_PMU_TYPE_CPUS] >> 32) &
2441 				    0xffffffff);
2442 
2443 	/*
2444 	 * Create an RB tree for traceID-metadata tuple.  Since the conversion
2445 	 * has to be made for each packet that gets decoded, optimizing access
2446 	 * in anything other than a sequential array is worth doing.
2447 	 */
2448 	traceid_list = intlist__new(NULL);
2449 	if (!traceid_list) {
2450 		err = -ENOMEM;
2451 		goto err_free_hdr;
2452 	}
2453 
2454 	metadata = zalloc(sizeof(*metadata) * num_cpu);
2455 	if (!metadata) {
2456 		err = -ENOMEM;
2457 		goto err_free_traceid_list;
2458 	}
2459 
2460 	/*
2461 	 * The metadata is stored in the auxtrace_info section and encodes
2462 	 * the configuration of the ARM embedded trace macrocell which is
2463 	 * required by the trace decoder to properly decode the trace due
2464 	 * to its highly compressed nature.
2465 	 */
2466 	for (j = 0; j < num_cpu; j++) {
2467 		if (ptr[i] == __perf_cs_etmv3_magic) {
2468 			metadata[j] = zalloc(sizeof(*metadata[j]) *
2469 					     CS_ETM_PRIV_MAX);
2470 			if (!metadata[j]) {
2471 				err = -ENOMEM;
2472 				goto err_free_metadata;
2473 			}
2474 			for (k = 0; k < CS_ETM_PRIV_MAX; k++)
2475 				metadata[j][k] = ptr[i + k];
2476 
2477 			/* The traceID is our handle */
2478 			idx = metadata[j][CS_ETM_ETMTRACEIDR];
2479 			i += CS_ETM_PRIV_MAX;
2480 		} else if (ptr[i] == __perf_cs_etmv4_magic) {
2481 			metadata[j] = zalloc(sizeof(*metadata[j]) *
2482 					     CS_ETMV4_PRIV_MAX);
2483 			if (!metadata[j]) {
2484 				err = -ENOMEM;
2485 				goto err_free_metadata;
2486 			}
2487 			for (k = 0; k < CS_ETMV4_PRIV_MAX; k++)
2488 				metadata[j][k] = ptr[i + k];
2489 
2490 			/* The traceID is our handle */
2491 			idx = metadata[j][CS_ETMV4_TRCTRACEIDR];
2492 			i += CS_ETMV4_PRIV_MAX;
2493 		}
2494 
2495 		/* Get an RB node for this CPU */
2496 		inode = intlist__findnew(traceid_list, idx);
2497 
2498 		/* Something went wrong, no need to continue */
2499 		if (!inode) {
2500 			err = -ENOMEM;
2501 			goto err_free_metadata;
2502 		}
2503 
2504 		/*
2505 		 * The node for that CPU should not be taken.
2506 		 * Back out if that's the case.
2507 		 */
2508 		if (inode->priv) {
2509 			err = -EINVAL;
2510 			goto err_free_metadata;
2511 		}
2512 		/* All good, associate the traceID with the metadata pointer */
2513 		inode->priv = metadata[j];
2514 	}
2515 
2516 	/*
2517 	 * Each of CS_HEADER_VERSION_0_MAX, CS_ETM_PRIV_MAX and
2518 	 * CS_ETMV4_PRIV_MAX mark how many double words are in the
2519 	 * global metadata, and each cpu's metadata respectively.
2520 	 * The following tests if the correct number of double words was
2521 	 * present in the auxtrace info section.
2522 	 */
2523 	if (i * 8 != priv_size) {
2524 		err = -EINVAL;
2525 		goto err_free_metadata;
2526 	}
2527 
2528 	etm = zalloc(sizeof(*etm));
2529 
2530 	if (!etm) {
2531 		err = -ENOMEM;
2532 		goto err_free_metadata;
2533 	}
2534 
2535 	err = auxtrace_queues__init(&etm->queues);
2536 	if (err)
2537 		goto err_free_etm;
2538 
2539 	etm->session = session;
2540 	etm->machine = &session->machines.host;
2541 
2542 	etm->num_cpu = num_cpu;
2543 	etm->pmu_type = pmu_type;
2544 	etm->snapshot_mode = (hdr[CS_ETM_SNAPSHOT] != 0);
2545 	etm->metadata = metadata;
2546 	etm->auxtrace_type = auxtrace_info->type;
2547 	etm->timeless_decoding = cs_etm__is_timeless_decoding(etm);
2548 
2549 	etm->auxtrace.process_event = cs_etm__process_event;
2550 	etm->auxtrace.process_auxtrace_event = cs_etm__process_auxtrace_event;
2551 	etm->auxtrace.flush_events = cs_etm__flush_events;
2552 	etm->auxtrace.free_events = cs_etm__free_events;
2553 	etm->auxtrace.free = cs_etm__free;
2554 	session->auxtrace = &etm->auxtrace;
2555 
2556 	etm->unknown_thread = thread__new(999999999, 999999999);
2557 	if (!etm->unknown_thread) {
2558 		err = -ENOMEM;
2559 		goto err_free_queues;
2560 	}
2561 
2562 	/*
2563 	 * Initialize list node so that at thread__zput() we can avoid
2564 	 * segmentation fault at list_del_init().
2565 	 */
2566 	INIT_LIST_HEAD(&etm->unknown_thread->node);
2567 
2568 	err = thread__set_comm(etm->unknown_thread, "unknown", 0);
2569 	if (err)
2570 		goto err_delete_thread;
2571 
2572 	if (thread__init_map_groups(etm->unknown_thread, etm->machine)) {
2573 		err = -ENOMEM;
2574 		goto err_delete_thread;
2575 	}
2576 
2577 	if (dump_trace) {
2578 		cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
2579 		return 0;
2580 	}
2581 
2582 	if (session->itrace_synth_opts->set) {
2583 		etm->synth_opts = *session->itrace_synth_opts;
2584 	} else {
2585 		itrace_synth_opts__set_default(&etm->synth_opts,
2586 				session->itrace_synth_opts->default_no_sample);
2587 		etm->synth_opts.callchain = false;
2588 	}
2589 
2590 	err = cs_etm__synth_events(etm, session);
2591 	if (err)
2592 		goto err_delete_thread;
2593 
2594 	err = auxtrace_queues__process_index(&etm->queues, session);
2595 	if (err)
2596 		goto err_delete_thread;
2597 
2598 	etm->data_queued = etm->queues.populated;
2599 
2600 	return 0;
2601 
2602 err_delete_thread:
2603 	thread__zput(etm->unknown_thread);
2604 err_free_queues:
2605 	auxtrace_queues__free(&etm->queues);
2606 	session->auxtrace = NULL;
2607 err_free_etm:
2608 	zfree(&etm);
2609 err_free_metadata:
2610 	/* No need to check @metadata[j], free(NULL) is supported */
2611 	for (j = 0; j < num_cpu; j++)
2612 		zfree(&metadata[j]);
2613 	zfree(&metadata);
2614 err_free_traceid_list:
2615 	intlist__delete(traceid_list);
2616 err_free_hdr:
2617 	zfree(&hdr);
2618 
2619 	return err;
2620 }
2621