xref: /openbmc/linux/tools/perf/util/cs-etm.c (revision 023e4163)
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 
15 #include <opencsd/ocsd_if_types.h>
16 #include <stdlib.h>
17 
18 #include "auxtrace.h"
19 #include "color.h"
20 #include "cs-etm.h"
21 #include "cs-etm-decoder/cs-etm-decoder.h"
22 #include "debug.h"
23 #include "evlist.h"
24 #include "intlist.h"
25 #include "machine.h"
26 #include "map.h"
27 #include "perf.h"
28 #include "symbol.h"
29 #include "thread.h"
30 #include "thread_map.h"
31 #include "thread-stack.h"
32 #include "util.h"
33 
34 #define MAX_TIMESTAMP (~0ULL)
35 
36 struct cs_etm_auxtrace {
37 	struct auxtrace auxtrace;
38 	struct auxtrace_queues queues;
39 	struct auxtrace_heap heap;
40 	struct itrace_synth_opts synth_opts;
41 	struct perf_session *session;
42 	struct machine *machine;
43 	struct thread *unknown_thread;
44 
45 	u8 timeless_decoding;
46 	u8 snapshot_mode;
47 	u8 data_queued;
48 	u8 sample_branches;
49 	u8 sample_instructions;
50 
51 	int num_cpu;
52 	u32 auxtrace_type;
53 	u64 branches_sample_type;
54 	u64 branches_id;
55 	u64 instructions_sample_type;
56 	u64 instructions_sample_period;
57 	u64 instructions_id;
58 	u64 **metadata;
59 	u64 kernel_start;
60 	unsigned int pmu_type;
61 };
62 
63 struct cs_etm_queue {
64 	struct cs_etm_auxtrace *etm;
65 	struct thread *thread;
66 	struct cs_etm_decoder *decoder;
67 	struct auxtrace_buffer *buffer;
68 	union perf_event *event_buf;
69 	unsigned int queue_nr;
70 	pid_t pid, tid;
71 	int cpu;
72 	u64 offset;
73 	u64 period_instructions;
74 	struct branch_stack *last_branch;
75 	struct branch_stack *last_branch_rb;
76 	size_t last_branch_pos;
77 	struct cs_etm_packet *prev_packet;
78 	struct cs_etm_packet *packet;
79 	const unsigned char *buf;
80 	size_t buf_len, buf_used;
81 };
82 
83 static int cs_etm__update_queues(struct cs_etm_auxtrace *etm);
84 static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
85 					   pid_t tid);
86 
87 /* PTMs ETMIDR [11:8] set to b0011 */
88 #define ETMIDR_PTM_VERSION 0x00000300
89 
90 static u32 cs_etm__get_v7_protocol_version(u32 etmidr)
91 {
92 	etmidr &= ETMIDR_PTM_VERSION;
93 
94 	if (etmidr == ETMIDR_PTM_VERSION)
95 		return CS_ETM_PROTO_PTM;
96 
97 	return CS_ETM_PROTO_ETMV3;
98 }
99 
100 static int cs_etm__get_magic(u8 trace_chan_id, u64 *magic)
101 {
102 	struct int_node *inode;
103 	u64 *metadata;
104 
105 	inode = intlist__find(traceid_list, trace_chan_id);
106 	if (!inode)
107 		return -EINVAL;
108 
109 	metadata = inode->priv;
110 	*magic = metadata[CS_ETM_MAGIC];
111 	return 0;
112 }
113 
114 int cs_etm__get_cpu(u8 trace_chan_id, int *cpu)
115 {
116 	struct int_node *inode;
117 	u64 *metadata;
118 
119 	inode = intlist__find(traceid_list, trace_chan_id);
120 	if (!inode)
121 		return -EINVAL;
122 
123 	metadata = inode->priv;
124 	*cpu = (int)metadata[CS_ETM_CPU];
125 	return 0;
126 }
127 
128 static void cs_etm__packet_dump(const char *pkt_string)
129 {
130 	const char *color = PERF_COLOR_BLUE;
131 	int len = strlen(pkt_string);
132 
133 	if (len && (pkt_string[len-1] == '\n'))
134 		color_fprintf(stdout, color, "	%s", pkt_string);
135 	else
136 		color_fprintf(stdout, color, "	%s\n", pkt_string);
137 
138 	fflush(stdout);
139 }
140 
141 static void cs_etm__set_trace_param_etmv3(struct cs_etm_trace_params *t_params,
142 					  struct cs_etm_auxtrace *etm, int idx,
143 					  u32 etmidr)
144 {
145 	u64 **metadata = etm->metadata;
146 
147 	t_params[idx].protocol = cs_etm__get_v7_protocol_version(etmidr);
148 	t_params[idx].etmv3.reg_ctrl = metadata[idx][CS_ETM_ETMCR];
149 	t_params[idx].etmv3.reg_trc_id = metadata[idx][CS_ETM_ETMTRACEIDR];
150 }
151 
152 static void cs_etm__set_trace_param_etmv4(struct cs_etm_trace_params *t_params,
153 					  struct cs_etm_auxtrace *etm, int idx)
154 {
155 	u64 **metadata = etm->metadata;
156 
157 	t_params[idx].protocol = CS_ETM_PROTO_ETMV4i;
158 	t_params[idx].etmv4.reg_idr0 = metadata[idx][CS_ETMV4_TRCIDR0];
159 	t_params[idx].etmv4.reg_idr1 = metadata[idx][CS_ETMV4_TRCIDR1];
160 	t_params[idx].etmv4.reg_idr2 = metadata[idx][CS_ETMV4_TRCIDR2];
161 	t_params[idx].etmv4.reg_idr8 = metadata[idx][CS_ETMV4_TRCIDR8];
162 	t_params[idx].etmv4.reg_configr = metadata[idx][CS_ETMV4_TRCCONFIGR];
163 	t_params[idx].etmv4.reg_traceidr = metadata[idx][CS_ETMV4_TRCTRACEIDR];
164 }
165 
166 static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
167 				     struct cs_etm_auxtrace *etm)
168 {
169 	int i;
170 	u32 etmidr;
171 	u64 architecture;
172 
173 	for (i = 0; i < etm->num_cpu; i++) {
174 		architecture = etm->metadata[i][CS_ETM_MAGIC];
175 
176 		switch (architecture) {
177 		case __perf_cs_etmv3_magic:
178 			etmidr = etm->metadata[i][CS_ETM_ETMIDR];
179 			cs_etm__set_trace_param_etmv3(t_params, etm, i, etmidr);
180 			break;
181 		case __perf_cs_etmv4_magic:
182 			cs_etm__set_trace_param_etmv4(t_params, etm, i);
183 			break;
184 		default:
185 			return -EINVAL;
186 		}
187 	}
188 
189 	return 0;
190 }
191 
192 static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
193 				       struct cs_etm_queue *etmq,
194 				       enum cs_etm_decoder_operation mode)
195 {
196 	int ret = -EINVAL;
197 
198 	if (!(mode < CS_ETM_OPERATION_MAX))
199 		goto out;
200 
201 	d_params->packet_printer = cs_etm__packet_dump;
202 	d_params->operation = mode;
203 	d_params->data = etmq;
204 	d_params->formatted = true;
205 	d_params->fsyncs = false;
206 	d_params->hsyncs = false;
207 	d_params->frame_aligned = true;
208 
209 	ret = 0;
210 out:
211 	return ret;
212 }
213 
214 static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
215 			       struct auxtrace_buffer *buffer)
216 {
217 	int ret;
218 	const char *color = PERF_COLOR_BLUE;
219 	struct cs_etm_decoder_params d_params;
220 	struct cs_etm_trace_params *t_params;
221 	struct cs_etm_decoder *decoder;
222 	size_t buffer_used = 0;
223 
224 	fprintf(stdout, "\n");
225 	color_fprintf(stdout, color,
226 		     ". ... CoreSight ETM Trace data: size %zu bytes\n",
227 		     buffer->size);
228 
229 	/* Use metadata to fill in trace parameters for trace decoder */
230 	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
231 
232 	if (!t_params)
233 		return;
234 
235 	if (cs_etm__init_trace_params(t_params, etm))
236 		goto out_free;
237 
238 	/* Set decoder parameters to simply print the trace packets */
239 	if (cs_etm__init_decoder_params(&d_params, NULL,
240 					CS_ETM_OPERATION_PRINT))
241 		goto out_free;
242 
243 	decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
244 
245 	if (!decoder)
246 		goto out_free;
247 	do {
248 		size_t consumed;
249 
250 		ret = cs_etm_decoder__process_data_block(
251 				decoder, buffer->offset,
252 				&((u8 *)buffer->data)[buffer_used],
253 				buffer->size - buffer_used, &consumed);
254 		if (ret)
255 			break;
256 
257 		buffer_used += consumed;
258 	} while (buffer_used < buffer->size);
259 
260 	cs_etm_decoder__free(decoder);
261 
262 out_free:
263 	zfree(&t_params);
264 }
265 
266 static int cs_etm__flush_events(struct perf_session *session,
267 				struct perf_tool *tool)
268 {
269 	int ret;
270 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
271 						   struct cs_etm_auxtrace,
272 						   auxtrace);
273 	if (dump_trace)
274 		return 0;
275 
276 	if (!tool->ordered_events)
277 		return -EINVAL;
278 
279 	if (!etm->timeless_decoding)
280 		return -EINVAL;
281 
282 	ret = cs_etm__update_queues(etm);
283 
284 	if (ret < 0)
285 		return ret;
286 
287 	return cs_etm__process_timeless_queues(etm, -1);
288 }
289 
290 static void cs_etm__free_queue(void *priv)
291 {
292 	struct cs_etm_queue *etmq = priv;
293 
294 	if (!etmq)
295 		return;
296 
297 	thread__zput(etmq->thread);
298 	cs_etm_decoder__free(etmq->decoder);
299 	zfree(&etmq->event_buf);
300 	zfree(&etmq->last_branch);
301 	zfree(&etmq->last_branch_rb);
302 	zfree(&etmq->prev_packet);
303 	zfree(&etmq->packet);
304 	free(etmq);
305 }
306 
307 static void cs_etm__free_events(struct perf_session *session)
308 {
309 	unsigned int i;
310 	struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
311 						   struct cs_etm_auxtrace,
312 						   auxtrace);
313 	struct auxtrace_queues *queues = &aux->queues;
314 
315 	for (i = 0; i < queues->nr_queues; i++) {
316 		cs_etm__free_queue(queues->queue_array[i].priv);
317 		queues->queue_array[i].priv = NULL;
318 	}
319 
320 	auxtrace_queues__free(queues);
321 }
322 
323 static void cs_etm__free(struct perf_session *session)
324 {
325 	int i;
326 	struct int_node *inode, *tmp;
327 	struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
328 						   struct cs_etm_auxtrace,
329 						   auxtrace);
330 	cs_etm__free_events(session);
331 	session->auxtrace = NULL;
332 
333 	/* First remove all traceID/metadata nodes for the RB tree */
334 	intlist__for_each_entry_safe(inode, tmp, traceid_list)
335 		intlist__remove(traceid_list, inode);
336 	/* Then the RB tree itself */
337 	intlist__delete(traceid_list);
338 
339 	for (i = 0; i < aux->num_cpu; i++)
340 		zfree(&aux->metadata[i]);
341 
342 	thread__zput(aux->unknown_thread);
343 	zfree(&aux->metadata);
344 	zfree(&aux);
345 }
346 
347 static u8 cs_etm__cpu_mode(struct cs_etm_queue *etmq, u64 address)
348 {
349 	struct machine *machine;
350 
351 	machine = etmq->etm->machine;
352 
353 	if (address >= etmq->etm->kernel_start) {
354 		if (machine__is_host(machine))
355 			return PERF_RECORD_MISC_KERNEL;
356 		else
357 			return PERF_RECORD_MISC_GUEST_KERNEL;
358 	} else {
359 		if (machine__is_host(machine))
360 			return PERF_RECORD_MISC_USER;
361 		else if (perf_guest)
362 			return PERF_RECORD_MISC_GUEST_USER;
363 		else
364 			return PERF_RECORD_MISC_HYPERVISOR;
365 	}
366 }
367 
368 static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
369 			      size_t size, u8 *buffer)
370 {
371 	u8  cpumode;
372 	u64 offset;
373 	int len;
374 	struct	 thread *thread;
375 	struct	 machine *machine;
376 	struct	 addr_location al;
377 
378 	if (!etmq)
379 		return 0;
380 
381 	machine = etmq->etm->machine;
382 	cpumode = cs_etm__cpu_mode(etmq, address);
383 
384 	thread = etmq->thread;
385 	if (!thread) {
386 		if (cpumode != PERF_RECORD_MISC_KERNEL)
387 			return 0;
388 		thread = etmq->etm->unknown_thread;
389 	}
390 
391 	if (!thread__find_map(thread, cpumode, address, &al) || !al.map->dso)
392 		return 0;
393 
394 	if (al.map->dso->data.status == DSO_DATA_STATUS_ERROR &&
395 	    dso__data_status_seen(al.map->dso, DSO_DATA_STATUS_SEEN_ITRACE))
396 		return 0;
397 
398 	offset = al.map->map_ip(al.map, address);
399 
400 	map__load(al.map);
401 
402 	len = dso__data_read_offset(al.map->dso, machine, offset, buffer, size);
403 
404 	if (len <= 0)
405 		return 0;
406 
407 	return len;
408 }
409 
410 static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
411 {
412 	struct cs_etm_decoder_params d_params;
413 	struct cs_etm_trace_params  *t_params = NULL;
414 	struct cs_etm_queue *etmq;
415 	size_t szp = sizeof(struct cs_etm_packet);
416 
417 	etmq = zalloc(sizeof(*etmq));
418 	if (!etmq)
419 		return NULL;
420 
421 	etmq->packet = zalloc(szp);
422 	if (!etmq->packet)
423 		goto out_free;
424 
425 	if (etm->synth_opts.last_branch || etm->sample_branches) {
426 		etmq->prev_packet = zalloc(szp);
427 		if (!etmq->prev_packet)
428 			goto out_free;
429 	}
430 
431 	if (etm->synth_opts.last_branch) {
432 		size_t sz = sizeof(struct branch_stack);
433 
434 		sz += etm->synth_opts.last_branch_sz *
435 		      sizeof(struct branch_entry);
436 		etmq->last_branch = zalloc(sz);
437 		if (!etmq->last_branch)
438 			goto out_free;
439 		etmq->last_branch_rb = zalloc(sz);
440 		if (!etmq->last_branch_rb)
441 			goto out_free;
442 	}
443 
444 	etmq->event_buf = malloc(PERF_SAMPLE_MAX_SIZE);
445 	if (!etmq->event_buf)
446 		goto out_free;
447 
448 	/* Use metadata to fill in trace parameters for trace decoder */
449 	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
450 
451 	if (!t_params)
452 		goto out_free;
453 
454 	if (cs_etm__init_trace_params(t_params, etm))
455 		goto out_free;
456 
457 	/* Set decoder parameters to decode trace packets */
458 	if (cs_etm__init_decoder_params(&d_params, etmq,
459 					CS_ETM_OPERATION_DECODE))
460 		goto out_free;
461 
462 	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
463 
464 	if (!etmq->decoder)
465 		goto out_free;
466 
467 	/*
468 	 * Register a function to handle all memory accesses required by
469 	 * the trace decoder library.
470 	 */
471 	if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
472 					      0x0L, ((u64) -1L),
473 					      cs_etm__mem_access))
474 		goto out_free_decoder;
475 
476 	zfree(&t_params);
477 	return etmq;
478 
479 out_free_decoder:
480 	cs_etm_decoder__free(etmq->decoder);
481 out_free:
482 	zfree(&t_params);
483 	zfree(&etmq->event_buf);
484 	zfree(&etmq->last_branch);
485 	zfree(&etmq->last_branch_rb);
486 	zfree(&etmq->prev_packet);
487 	zfree(&etmq->packet);
488 	free(etmq);
489 
490 	return NULL;
491 }
492 
493 static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
494 			       struct auxtrace_queue *queue,
495 			       unsigned int queue_nr)
496 {
497 	int ret = 0;
498 	struct cs_etm_queue *etmq = queue->priv;
499 
500 	if (list_empty(&queue->head) || etmq)
501 		goto out;
502 
503 	etmq = cs_etm__alloc_queue(etm);
504 
505 	if (!etmq) {
506 		ret = -ENOMEM;
507 		goto out;
508 	}
509 
510 	queue->priv = etmq;
511 	etmq->etm = etm;
512 	etmq->queue_nr = queue_nr;
513 	etmq->cpu = queue->cpu;
514 	etmq->tid = queue->tid;
515 	etmq->pid = -1;
516 	etmq->offset = 0;
517 	etmq->period_instructions = 0;
518 
519 out:
520 	return ret;
521 }
522 
523 static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
524 {
525 	unsigned int i;
526 	int ret;
527 
528 	if (!etm->kernel_start)
529 		etm->kernel_start = machine__kernel_start(etm->machine);
530 
531 	for (i = 0; i < etm->queues.nr_queues; i++) {
532 		ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
533 		if (ret)
534 			return ret;
535 	}
536 
537 	return 0;
538 }
539 
540 static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
541 {
542 	if (etm->queues.new_data) {
543 		etm->queues.new_data = false;
544 		return cs_etm__setup_queues(etm);
545 	}
546 
547 	return 0;
548 }
549 
550 static inline void cs_etm__copy_last_branch_rb(struct cs_etm_queue *etmq)
551 {
552 	struct branch_stack *bs_src = etmq->last_branch_rb;
553 	struct branch_stack *bs_dst = etmq->last_branch;
554 	size_t nr = 0;
555 
556 	/*
557 	 * Set the number of records before early exit: ->nr is used to
558 	 * determine how many branches to copy from ->entries.
559 	 */
560 	bs_dst->nr = bs_src->nr;
561 
562 	/*
563 	 * Early exit when there is nothing to copy.
564 	 */
565 	if (!bs_src->nr)
566 		return;
567 
568 	/*
569 	 * As bs_src->entries is a circular buffer, we need to copy from it in
570 	 * two steps.  First, copy the branches from the most recently inserted
571 	 * branch ->last_branch_pos until the end of bs_src->entries buffer.
572 	 */
573 	nr = etmq->etm->synth_opts.last_branch_sz - etmq->last_branch_pos;
574 	memcpy(&bs_dst->entries[0],
575 	       &bs_src->entries[etmq->last_branch_pos],
576 	       sizeof(struct branch_entry) * nr);
577 
578 	/*
579 	 * If we wrapped around at least once, the branches from the beginning
580 	 * of the bs_src->entries buffer and until the ->last_branch_pos element
581 	 * are older valid branches: copy them over.  The total number of
582 	 * branches copied over will be equal to the number of branches asked by
583 	 * the user in last_branch_sz.
584 	 */
585 	if (bs_src->nr >= etmq->etm->synth_opts.last_branch_sz) {
586 		memcpy(&bs_dst->entries[nr],
587 		       &bs_src->entries[0],
588 		       sizeof(struct branch_entry) * etmq->last_branch_pos);
589 	}
590 }
591 
592 static inline void cs_etm__reset_last_branch_rb(struct cs_etm_queue *etmq)
593 {
594 	etmq->last_branch_pos = 0;
595 	etmq->last_branch_rb->nr = 0;
596 }
597 
598 static inline int cs_etm__t32_instr_size(struct cs_etm_queue *etmq,
599 					 u64 addr) {
600 	u8 instrBytes[2];
601 
602 	cs_etm__mem_access(etmq, addr, ARRAY_SIZE(instrBytes), instrBytes);
603 	/*
604 	 * T32 instruction size is indicated by bits[15:11] of the first
605 	 * 16-bit word of the instruction: 0b11101, 0b11110 and 0b11111
606 	 * denote a 32-bit instruction.
607 	 */
608 	return ((instrBytes[1] & 0xF8) >= 0xE8) ? 4 : 2;
609 }
610 
611 static inline u64 cs_etm__first_executed_instr(struct cs_etm_packet *packet)
612 {
613 	/* Returns 0 for the CS_ETM_DISCONTINUITY packet */
614 	if (packet->sample_type == CS_ETM_DISCONTINUITY)
615 		return 0;
616 
617 	return packet->start_addr;
618 }
619 
620 static inline
621 u64 cs_etm__last_executed_instr(const struct cs_etm_packet *packet)
622 {
623 	/* Returns 0 for the CS_ETM_DISCONTINUITY packet */
624 	if (packet->sample_type == CS_ETM_DISCONTINUITY)
625 		return 0;
626 
627 	return packet->end_addr - packet->last_instr_size;
628 }
629 
630 static inline u64 cs_etm__instr_addr(struct cs_etm_queue *etmq,
631 				     const struct cs_etm_packet *packet,
632 				     u64 offset)
633 {
634 	if (packet->isa == CS_ETM_ISA_T32) {
635 		u64 addr = packet->start_addr;
636 
637 		while (offset > 0) {
638 			addr += cs_etm__t32_instr_size(etmq, addr);
639 			offset--;
640 		}
641 		return addr;
642 	}
643 
644 	/* Assume a 4 byte instruction size (A32/A64) */
645 	return packet->start_addr + offset * 4;
646 }
647 
648 static void cs_etm__update_last_branch_rb(struct cs_etm_queue *etmq)
649 {
650 	struct branch_stack *bs = etmq->last_branch_rb;
651 	struct branch_entry *be;
652 
653 	/*
654 	 * The branches are recorded in a circular buffer in reverse
655 	 * chronological order: we start recording from the last element of the
656 	 * buffer down.  After writing the first element of the stack, move the
657 	 * insert position back to the end of the buffer.
658 	 */
659 	if (!etmq->last_branch_pos)
660 		etmq->last_branch_pos = etmq->etm->synth_opts.last_branch_sz;
661 
662 	etmq->last_branch_pos -= 1;
663 
664 	be       = &bs->entries[etmq->last_branch_pos];
665 	be->from = cs_etm__last_executed_instr(etmq->prev_packet);
666 	be->to	 = cs_etm__first_executed_instr(etmq->packet);
667 	/* No support for mispredict */
668 	be->flags.mispred = 0;
669 	be->flags.predicted = 1;
670 
671 	/*
672 	 * Increment bs->nr until reaching the number of last branches asked by
673 	 * the user on the command line.
674 	 */
675 	if (bs->nr < etmq->etm->synth_opts.last_branch_sz)
676 		bs->nr += 1;
677 }
678 
679 static int cs_etm__inject_event(union perf_event *event,
680 			       struct perf_sample *sample, u64 type)
681 {
682 	event->header.size = perf_event__sample_event_size(sample, type, 0);
683 	return perf_event__synthesize_sample(event, type, 0, sample);
684 }
685 
686 
687 static int
688 cs_etm__get_trace(struct cs_etm_queue *etmq)
689 {
690 	struct auxtrace_buffer *aux_buffer = etmq->buffer;
691 	struct auxtrace_buffer *old_buffer = aux_buffer;
692 	struct auxtrace_queue *queue;
693 
694 	queue = &etmq->etm->queues.queue_array[etmq->queue_nr];
695 
696 	aux_buffer = auxtrace_buffer__next(queue, aux_buffer);
697 
698 	/* If no more data, drop the previous auxtrace_buffer and return */
699 	if (!aux_buffer) {
700 		if (old_buffer)
701 			auxtrace_buffer__drop_data(old_buffer);
702 		etmq->buf_len = 0;
703 		return 0;
704 	}
705 
706 	etmq->buffer = aux_buffer;
707 
708 	/* If the aux_buffer doesn't have data associated, try to load it */
709 	if (!aux_buffer->data) {
710 		/* get the file desc associated with the perf data file */
711 		int fd = perf_data__fd(etmq->etm->session->data);
712 
713 		aux_buffer->data = auxtrace_buffer__get_data(aux_buffer, fd);
714 		if (!aux_buffer->data)
715 			return -ENOMEM;
716 	}
717 
718 	/* If valid, drop the previous buffer */
719 	if (old_buffer)
720 		auxtrace_buffer__drop_data(old_buffer);
721 
722 	etmq->buf_used = 0;
723 	etmq->buf_len = aux_buffer->size;
724 	etmq->buf = aux_buffer->data;
725 
726 	return etmq->buf_len;
727 }
728 
729 static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
730 				    struct auxtrace_queue *queue)
731 {
732 	struct cs_etm_queue *etmq = queue->priv;
733 
734 	/* CPU-wide tracing isn't supported yet */
735 	if (queue->tid == -1)
736 		return;
737 
738 	if ((!etmq->thread) && (etmq->tid != -1))
739 		etmq->thread = machine__find_thread(etm->machine, -1,
740 						    etmq->tid);
741 
742 	if (etmq->thread) {
743 		etmq->pid = etmq->thread->pid_;
744 		if (queue->cpu == -1)
745 			etmq->cpu = etmq->thread->cpu;
746 	}
747 }
748 
749 static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
750 					    u64 addr, u64 period)
751 {
752 	int ret = 0;
753 	struct cs_etm_auxtrace *etm = etmq->etm;
754 	union perf_event *event = etmq->event_buf;
755 	struct perf_sample sample = {.ip = 0,};
756 
757 	event->sample.header.type = PERF_RECORD_SAMPLE;
758 	event->sample.header.misc = cs_etm__cpu_mode(etmq, addr);
759 	event->sample.header.size = sizeof(struct perf_event_header);
760 
761 	sample.ip = addr;
762 	sample.pid = etmq->pid;
763 	sample.tid = etmq->tid;
764 	sample.id = etmq->etm->instructions_id;
765 	sample.stream_id = etmq->etm->instructions_id;
766 	sample.period = period;
767 	sample.cpu = etmq->packet->cpu;
768 	sample.flags = etmq->prev_packet->flags;
769 	sample.insn_len = 1;
770 	sample.cpumode = event->sample.header.misc;
771 
772 	if (etm->synth_opts.last_branch) {
773 		cs_etm__copy_last_branch_rb(etmq);
774 		sample.branch_stack = etmq->last_branch;
775 	}
776 
777 	if (etm->synth_opts.inject) {
778 		ret = cs_etm__inject_event(event, &sample,
779 					   etm->instructions_sample_type);
780 		if (ret)
781 			return ret;
782 	}
783 
784 	ret = perf_session__deliver_synth_event(etm->session, event, &sample);
785 
786 	if (ret)
787 		pr_err(
788 			"CS ETM Trace: failed to deliver instruction event, error %d\n",
789 			ret);
790 
791 	if (etm->synth_opts.last_branch)
792 		cs_etm__reset_last_branch_rb(etmq);
793 
794 	return ret;
795 }
796 
797 /*
798  * The cs etm packet encodes an instruction range between a branch target
799  * and the next taken branch. Generate sample accordingly.
800  */
801 static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq)
802 {
803 	int ret = 0;
804 	struct cs_etm_auxtrace *etm = etmq->etm;
805 	struct perf_sample sample = {.ip = 0,};
806 	union perf_event *event = etmq->event_buf;
807 	struct dummy_branch_stack {
808 		u64			nr;
809 		struct branch_entry	entries;
810 	} dummy_bs;
811 	u64 ip;
812 
813 	ip = cs_etm__last_executed_instr(etmq->prev_packet);
814 
815 	event->sample.header.type = PERF_RECORD_SAMPLE;
816 	event->sample.header.misc = cs_etm__cpu_mode(etmq, ip);
817 	event->sample.header.size = sizeof(struct perf_event_header);
818 
819 	sample.ip = ip;
820 	sample.pid = etmq->pid;
821 	sample.tid = etmq->tid;
822 	sample.addr = cs_etm__first_executed_instr(etmq->packet);
823 	sample.id = etmq->etm->branches_id;
824 	sample.stream_id = etmq->etm->branches_id;
825 	sample.period = 1;
826 	sample.cpu = etmq->packet->cpu;
827 	sample.flags = etmq->prev_packet->flags;
828 	sample.cpumode = event->sample.header.misc;
829 
830 	/*
831 	 * perf report cannot handle events without a branch stack
832 	 */
833 	if (etm->synth_opts.last_branch) {
834 		dummy_bs = (struct dummy_branch_stack){
835 			.nr = 1,
836 			.entries = {
837 				.from = sample.ip,
838 				.to = sample.addr,
839 			},
840 		};
841 		sample.branch_stack = (struct branch_stack *)&dummy_bs;
842 	}
843 
844 	if (etm->synth_opts.inject) {
845 		ret = cs_etm__inject_event(event, &sample,
846 					   etm->branches_sample_type);
847 		if (ret)
848 			return ret;
849 	}
850 
851 	ret = perf_session__deliver_synth_event(etm->session, event, &sample);
852 
853 	if (ret)
854 		pr_err(
855 		"CS ETM Trace: failed to deliver instruction event, error %d\n",
856 		ret);
857 
858 	return ret;
859 }
860 
861 struct cs_etm_synth {
862 	struct perf_tool dummy_tool;
863 	struct perf_session *session;
864 };
865 
866 static int cs_etm__event_synth(struct perf_tool *tool,
867 			       union perf_event *event,
868 			       struct perf_sample *sample __maybe_unused,
869 			       struct machine *machine __maybe_unused)
870 {
871 	struct cs_etm_synth *cs_etm_synth =
872 		      container_of(tool, struct cs_etm_synth, dummy_tool);
873 
874 	return perf_session__deliver_synth_event(cs_etm_synth->session,
875 						 event, NULL);
876 }
877 
878 static int cs_etm__synth_event(struct perf_session *session,
879 			       struct perf_event_attr *attr, u64 id)
880 {
881 	struct cs_etm_synth cs_etm_synth;
882 
883 	memset(&cs_etm_synth, 0, sizeof(struct cs_etm_synth));
884 	cs_etm_synth.session = session;
885 
886 	return perf_event__synthesize_attr(&cs_etm_synth.dummy_tool, attr, 1,
887 					   &id, cs_etm__event_synth);
888 }
889 
890 static int cs_etm__synth_events(struct cs_etm_auxtrace *etm,
891 				struct perf_session *session)
892 {
893 	struct perf_evlist *evlist = session->evlist;
894 	struct perf_evsel *evsel;
895 	struct perf_event_attr attr;
896 	bool found = false;
897 	u64 id;
898 	int err;
899 
900 	evlist__for_each_entry(evlist, evsel) {
901 		if (evsel->attr.type == etm->pmu_type) {
902 			found = true;
903 			break;
904 		}
905 	}
906 
907 	if (!found) {
908 		pr_debug("No selected events with CoreSight Trace data\n");
909 		return 0;
910 	}
911 
912 	memset(&attr, 0, sizeof(struct perf_event_attr));
913 	attr.size = sizeof(struct perf_event_attr);
914 	attr.type = PERF_TYPE_HARDWARE;
915 	attr.sample_type = evsel->attr.sample_type & PERF_SAMPLE_MASK;
916 	attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
917 			    PERF_SAMPLE_PERIOD;
918 	if (etm->timeless_decoding)
919 		attr.sample_type &= ~(u64)PERF_SAMPLE_TIME;
920 	else
921 		attr.sample_type |= PERF_SAMPLE_TIME;
922 
923 	attr.exclude_user = evsel->attr.exclude_user;
924 	attr.exclude_kernel = evsel->attr.exclude_kernel;
925 	attr.exclude_hv = evsel->attr.exclude_hv;
926 	attr.exclude_host = evsel->attr.exclude_host;
927 	attr.exclude_guest = evsel->attr.exclude_guest;
928 	attr.sample_id_all = evsel->attr.sample_id_all;
929 	attr.read_format = evsel->attr.read_format;
930 
931 	/* create new id val to be a fixed offset from evsel id */
932 	id = evsel->id[0] + 1000000000;
933 
934 	if (!id)
935 		id = 1;
936 
937 	if (etm->synth_opts.branches) {
938 		attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
939 		attr.sample_period = 1;
940 		attr.sample_type |= PERF_SAMPLE_ADDR;
941 		err = cs_etm__synth_event(session, &attr, id);
942 		if (err)
943 			return err;
944 		etm->sample_branches = true;
945 		etm->branches_sample_type = attr.sample_type;
946 		etm->branches_id = id;
947 		id += 1;
948 		attr.sample_type &= ~(u64)PERF_SAMPLE_ADDR;
949 	}
950 
951 	if (etm->synth_opts.last_branch)
952 		attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;
953 
954 	if (etm->synth_opts.instructions) {
955 		attr.config = PERF_COUNT_HW_INSTRUCTIONS;
956 		attr.sample_period = etm->synth_opts.period;
957 		etm->instructions_sample_period = attr.sample_period;
958 		err = cs_etm__synth_event(session, &attr, id);
959 		if (err)
960 			return err;
961 		etm->sample_instructions = true;
962 		etm->instructions_sample_type = attr.sample_type;
963 		etm->instructions_id = id;
964 		id += 1;
965 	}
966 
967 	return 0;
968 }
969 
970 static int cs_etm__sample(struct cs_etm_queue *etmq)
971 {
972 	struct cs_etm_auxtrace *etm = etmq->etm;
973 	struct cs_etm_packet *tmp;
974 	int ret;
975 	u64 instrs_executed = etmq->packet->instr_count;
976 
977 	etmq->period_instructions += instrs_executed;
978 
979 	/*
980 	 * Record a branch when the last instruction in
981 	 * PREV_PACKET is a branch.
982 	 */
983 	if (etm->synth_opts.last_branch &&
984 	    etmq->prev_packet &&
985 	    etmq->prev_packet->sample_type == CS_ETM_RANGE &&
986 	    etmq->prev_packet->last_instr_taken_branch)
987 		cs_etm__update_last_branch_rb(etmq);
988 
989 	if (etm->sample_instructions &&
990 	    etmq->period_instructions >= etm->instructions_sample_period) {
991 		/*
992 		 * Emit instruction sample periodically
993 		 * TODO: allow period to be defined in cycles and clock time
994 		 */
995 
996 		/* Get number of instructions executed after the sample point */
997 		u64 instrs_over = etmq->period_instructions -
998 			etm->instructions_sample_period;
999 
1000 		/*
1001 		 * Calculate the address of the sampled instruction (-1 as
1002 		 * sample is reported as though instruction has just been
1003 		 * executed, but PC has not advanced to next instruction)
1004 		 */
1005 		u64 offset = (instrs_executed - instrs_over - 1);
1006 		u64 addr = cs_etm__instr_addr(etmq, etmq->packet, offset);
1007 
1008 		ret = cs_etm__synth_instruction_sample(
1009 			etmq, addr, etm->instructions_sample_period);
1010 		if (ret)
1011 			return ret;
1012 
1013 		/* Carry remaining instructions into next sample period */
1014 		etmq->period_instructions = instrs_over;
1015 	}
1016 
1017 	if (etm->sample_branches && etmq->prev_packet) {
1018 		bool generate_sample = false;
1019 
1020 		/* Generate sample for tracing on packet */
1021 		if (etmq->prev_packet->sample_type == CS_ETM_DISCONTINUITY)
1022 			generate_sample = true;
1023 
1024 		/* Generate sample for branch taken packet */
1025 		if (etmq->prev_packet->sample_type == CS_ETM_RANGE &&
1026 		    etmq->prev_packet->last_instr_taken_branch)
1027 			generate_sample = true;
1028 
1029 		if (generate_sample) {
1030 			ret = cs_etm__synth_branch_sample(etmq);
1031 			if (ret)
1032 				return ret;
1033 		}
1034 	}
1035 
1036 	if (etm->sample_branches || etm->synth_opts.last_branch) {
1037 		/*
1038 		 * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
1039 		 * the next incoming packet.
1040 		 */
1041 		tmp = etmq->packet;
1042 		etmq->packet = etmq->prev_packet;
1043 		etmq->prev_packet = tmp;
1044 	}
1045 
1046 	return 0;
1047 }
1048 
1049 static int cs_etm__exception(struct cs_etm_queue *etmq)
1050 {
1051 	/*
1052 	 * When the exception packet is inserted, whether the last instruction
1053 	 * in previous range packet is taken branch or not, we need to force
1054 	 * to set 'prev_packet->last_instr_taken_branch' to true.  This ensures
1055 	 * to generate branch sample for the instruction range before the
1056 	 * exception is trapped to kernel or before the exception returning.
1057 	 *
1058 	 * The exception packet includes the dummy address values, so don't
1059 	 * swap PACKET with PREV_PACKET.  This keeps PREV_PACKET to be useful
1060 	 * for generating instruction and branch samples.
1061 	 */
1062 	if (etmq->prev_packet->sample_type == CS_ETM_RANGE)
1063 		etmq->prev_packet->last_instr_taken_branch = true;
1064 
1065 	return 0;
1066 }
1067 
1068 static int cs_etm__flush(struct cs_etm_queue *etmq)
1069 {
1070 	int err = 0;
1071 	struct cs_etm_auxtrace *etm = etmq->etm;
1072 	struct cs_etm_packet *tmp;
1073 
1074 	if (!etmq->prev_packet)
1075 		return 0;
1076 
1077 	/* Handle start tracing packet */
1078 	if (etmq->prev_packet->sample_type == CS_ETM_EMPTY)
1079 		goto swap_packet;
1080 
1081 	if (etmq->etm->synth_opts.last_branch &&
1082 	    etmq->prev_packet->sample_type == CS_ETM_RANGE) {
1083 		/*
1084 		 * Generate a last branch event for the branches left in the
1085 		 * circular buffer at the end of the trace.
1086 		 *
1087 		 * Use the address of the end of the last reported execution
1088 		 * range
1089 		 */
1090 		u64 addr = cs_etm__last_executed_instr(etmq->prev_packet);
1091 
1092 		err = cs_etm__synth_instruction_sample(
1093 			etmq, addr,
1094 			etmq->period_instructions);
1095 		if (err)
1096 			return err;
1097 
1098 		etmq->period_instructions = 0;
1099 
1100 	}
1101 
1102 	if (etm->sample_branches &&
1103 	    etmq->prev_packet->sample_type == CS_ETM_RANGE) {
1104 		err = cs_etm__synth_branch_sample(etmq);
1105 		if (err)
1106 			return err;
1107 	}
1108 
1109 swap_packet:
1110 	if (etm->sample_branches || etm->synth_opts.last_branch) {
1111 		/*
1112 		 * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
1113 		 * the next incoming packet.
1114 		 */
1115 		tmp = etmq->packet;
1116 		etmq->packet = etmq->prev_packet;
1117 		etmq->prev_packet = tmp;
1118 	}
1119 
1120 	return err;
1121 }
1122 
1123 static int cs_etm__end_block(struct cs_etm_queue *etmq)
1124 {
1125 	int err;
1126 
1127 	/*
1128 	 * It has no new packet coming and 'etmq->packet' contains the stale
1129 	 * packet which was set at the previous time with packets swapping;
1130 	 * so skip to generate branch sample to avoid stale packet.
1131 	 *
1132 	 * For this case only flush branch stack and generate a last branch
1133 	 * event for the branches left in the circular buffer at the end of
1134 	 * the trace.
1135 	 */
1136 	if (etmq->etm->synth_opts.last_branch &&
1137 	    etmq->prev_packet->sample_type == CS_ETM_RANGE) {
1138 		/*
1139 		 * Use the address of the end of the last reported execution
1140 		 * range.
1141 		 */
1142 		u64 addr = cs_etm__last_executed_instr(etmq->prev_packet);
1143 
1144 		err = cs_etm__synth_instruction_sample(
1145 			etmq, addr,
1146 			etmq->period_instructions);
1147 		if (err)
1148 			return err;
1149 
1150 		etmq->period_instructions = 0;
1151 	}
1152 
1153 	return 0;
1154 }
1155 /*
1156  * cs_etm__get_data_block: Fetch a block from the auxtrace_buffer queue
1157  *			   if need be.
1158  * Returns:	< 0	if error
1159  *		= 0	if no more auxtrace_buffer to read
1160  *		> 0	if the current buffer isn't empty yet
1161  */
1162 static int cs_etm__get_data_block(struct cs_etm_queue *etmq)
1163 {
1164 	int ret;
1165 
1166 	if (!etmq->buf_len) {
1167 		ret = cs_etm__get_trace(etmq);
1168 		if (ret <= 0)
1169 			return ret;
1170 		/*
1171 		 * We cannot assume consecutive blocks in the data file
1172 		 * are contiguous, reset the decoder to force re-sync.
1173 		 */
1174 		ret = cs_etm_decoder__reset(etmq->decoder);
1175 		if (ret)
1176 			return ret;
1177 	}
1178 
1179 	return etmq->buf_len;
1180 }
1181 
1182 static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq,
1183 				 struct cs_etm_packet *packet,
1184 				 u64 end_addr)
1185 {
1186 	u16 instr16;
1187 	u32 instr32;
1188 	u64 addr;
1189 
1190 	switch (packet->isa) {
1191 	case CS_ETM_ISA_T32:
1192 		/*
1193 		 * The SVC of T32 is defined in ARM DDI 0487D.a, F5.1.247:
1194 		 *
1195 		 *  b'15         b'8
1196 		 * +-----------------+--------+
1197 		 * | 1 1 0 1 1 1 1 1 |  imm8  |
1198 		 * +-----------------+--------+
1199 		 *
1200 		 * According to the specifiction, it only defines SVC for T32
1201 		 * with 16 bits instruction and has no definition for 32bits;
1202 		 * so below only read 2 bytes as instruction size for T32.
1203 		 */
1204 		addr = end_addr - 2;
1205 		cs_etm__mem_access(etmq, addr, sizeof(instr16), (u8 *)&instr16);
1206 		if ((instr16 & 0xFF00) == 0xDF00)
1207 			return true;
1208 
1209 		break;
1210 	case CS_ETM_ISA_A32:
1211 		/*
1212 		 * The SVC of A32 is defined in ARM DDI 0487D.a, F5.1.247:
1213 		 *
1214 		 *  b'31 b'28 b'27 b'24
1215 		 * +---------+---------+-------------------------+
1216 		 * |  !1111  | 1 1 1 1 |        imm24            |
1217 		 * +---------+---------+-------------------------+
1218 		 */
1219 		addr = end_addr - 4;
1220 		cs_etm__mem_access(etmq, addr, sizeof(instr32), (u8 *)&instr32);
1221 		if ((instr32 & 0x0F000000) == 0x0F000000 &&
1222 		    (instr32 & 0xF0000000) != 0xF0000000)
1223 			return true;
1224 
1225 		break;
1226 	case CS_ETM_ISA_A64:
1227 		/*
1228 		 * The SVC of A64 is defined in ARM DDI 0487D.a, C6.2.294:
1229 		 *
1230 		 *  b'31               b'21           b'4     b'0
1231 		 * +-----------------------+---------+-----------+
1232 		 * | 1 1 0 1 0 1 0 0 0 0 0 |  imm16  | 0 0 0 0 1 |
1233 		 * +-----------------------+---------+-----------+
1234 		 */
1235 		addr = end_addr - 4;
1236 		cs_etm__mem_access(etmq, addr, sizeof(instr32), (u8 *)&instr32);
1237 		if ((instr32 & 0xFFE0001F) == 0xd4000001)
1238 			return true;
1239 
1240 		break;
1241 	case CS_ETM_ISA_UNKNOWN:
1242 	default:
1243 		break;
1244 	}
1245 
1246 	return false;
1247 }
1248 
1249 static bool cs_etm__is_syscall(struct cs_etm_queue *etmq, u64 magic)
1250 {
1251 	struct cs_etm_packet *packet = etmq->packet;
1252 	struct cs_etm_packet *prev_packet = etmq->prev_packet;
1253 
1254 	if (magic == __perf_cs_etmv3_magic)
1255 		if (packet->exception_number == CS_ETMV3_EXC_SVC)
1256 			return true;
1257 
1258 	/*
1259 	 * ETMv4 exception type CS_ETMV4_EXC_CALL covers SVC, SMC and
1260 	 * HVC cases; need to check if it's SVC instruction based on
1261 	 * packet address.
1262 	 */
1263 	if (magic == __perf_cs_etmv4_magic) {
1264 		if (packet->exception_number == CS_ETMV4_EXC_CALL &&
1265 		    cs_etm__is_svc_instr(etmq, prev_packet,
1266 					 prev_packet->end_addr))
1267 			return true;
1268 	}
1269 
1270 	return false;
1271 }
1272 
1273 static bool cs_etm__is_async_exception(struct cs_etm_queue *etmq, u64 magic)
1274 {
1275 	struct cs_etm_packet *packet = etmq->packet;
1276 
1277 	if (magic == __perf_cs_etmv3_magic)
1278 		if (packet->exception_number == CS_ETMV3_EXC_DEBUG_HALT ||
1279 		    packet->exception_number == CS_ETMV3_EXC_ASYNC_DATA_ABORT ||
1280 		    packet->exception_number == CS_ETMV3_EXC_PE_RESET ||
1281 		    packet->exception_number == CS_ETMV3_EXC_IRQ ||
1282 		    packet->exception_number == CS_ETMV3_EXC_FIQ)
1283 			return true;
1284 
1285 	if (magic == __perf_cs_etmv4_magic)
1286 		if (packet->exception_number == CS_ETMV4_EXC_RESET ||
1287 		    packet->exception_number == CS_ETMV4_EXC_DEBUG_HALT ||
1288 		    packet->exception_number == CS_ETMV4_EXC_SYSTEM_ERROR ||
1289 		    packet->exception_number == CS_ETMV4_EXC_INST_DEBUG ||
1290 		    packet->exception_number == CS_ETMV4_EXC_DATA_DEBUG ||
1291 		    packet->exception_number == CS_ETMV4_EXC_IRQ ||
1292 		    packet->exception_number == CS_ETMV4_EXC_FIQ)
1293 			return true;
1294 
1295 	return false;
1296 }
1297 
1298 static bool cs_etm__is_sync_exception(struct cs_etm_queue *etmq, u64 magic)
1299 {
1300 	struct cs_etm_packet *packet = etmq->packet;
1301 	struct cs_etm_packet *prev_packet = etmq->prev_packet;
1302 
1303 	if (magic == __perf_cs_etmv3_magic)
1304 		if (packet->exception_number == CS_ETMV3_EXC_SMC ||
1305 		    packet->exception_number == CS_ETMV3_EXC_HYP ||
1306 		    packet->exception_number == CS_ETMV3_EXC_JAZELLE_THUMBEE ||
1307 		    packet->exception_number == CS_ETMV3_EXC_UNDEFINED_INSTR ||
1308 		    packet->exception_number == CS_ETMV3_EXC_PREFETCH_ABORT ||
1309 		    packet->exception_number == CS_ETMV3_EXC_DATA_FAULT ||
1310 		    packet->exception_number == CS_ETMV3_EXC_GENERIC)
1311 			return true;
1312 
1313 	if (magic == __perf_cs_etmv4_magic) {
1314 		if (packet->exception_number == CS_ETMV4_EXC_TRAP ||
1315 		    packet->exception_number == CS_ETMV4_EXC_ALIGNMENT ||
1316 		    packet->exception_number == CS_ETMV4_EXC_INST_FAULT ||
1317 		    packet->exception_number == CS_ETMV4_EXC_DATA_FAULT)
1318 			return true;
1319 
1320 		/*
1321 		 * For CS_ETMV4_EXC_CALL, except SVC other instructions
1322 		 * (SMC, HVC) are taken as sync exceptions.
1323 		 */
1324 		if (packet->exception_number == CS_ETMV4_EXC_CALL &&
1325 		    !cs_etm__is_svc_instr(etmq, prev_packet,
1326 					  prev_packet->end_addr))
1327 			return true;
1328 
1329 		/*
1330 		 * ETMv4 has 5 bits for exception number; if the numbers
1331 		 * are in the range ( CS_ETMV4_EXC_FIQ, CS_ETMV4_EXC_END ]
1332 		 * they are implementation defined exceptions.
1333 		 *
1334 		 * For this case, simply take it as sync exception.
1335 		 */
1336 		if (packet->exception_number > CS_ETMV4_EXC_FIQ &&
1337 		    packet->exception_number <= CS_ETMV4_EXC_END)
1338 			return true;
1339 	}
1340 
1341 	return false;
1342 }
1343 
1344 static int cs_etm__set_sample_flags(struct cs_etm_queue *etmq)
1345 {
1346 	struct cs_etm_packet *packet = etmq->packet;
1347 	struct cs_etm_packet *prev_packet = etmq->prev_packet;
1348 	u64 magic;
1349 	int ret;
1350 
1351 	switch (packet->sample_type) {
1352 	case CS_ETM_RANGE:
1353 		/*
1354 		 * Immediate branch instruction without neither link nor
1355 		 * return flag, it's normal branch instruction within
1356 		 * the function.
1357 		 */
1358 		if (packet->last_instr_type == OCSD_INSTR_BR &&
1359 		    packet->last_instr_subtype == OCSD_S_INSTR_NONE) {
1360 			packet->flags = PERF_IP_FLAG_BRANCH;
1361 
1362 			if (packet->last_instr_cond)
1363 				packet->flags |= PERF_IP_FLAG_CONDITIONAL;
1364 		}
1365 
1366 		/*
1367 		 * Immediate branch instruction with link (e.g. BL), this is
1368 		 * branch instruction for function call.
1369 		 */
1370 		if (packet->last_instr_type == OCSD_INSTR_BR &&
1371 		    packet->last_instr_subtype == OCSD_S_INSTR_BR_LINK)
1372 			packet->flags = PERF_IP_FLAG_BRANCH |
1373 					PERF_IP_FLAG_CALL;
1374 
1375 		/*
1376 		 * Indirect branch instruction with link (e.g. BLR), this is
1377 		 * branch instruction for function call.
1378 		 */
1379 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1380 		    packet->last_instr_subtype == OCSD_S_INSTR_BR_LINK)
1381 			packet->flags = PERF_IP_FLAG_BRANCH |
1382 					PERF_IP_FLAG_CALL;
1383 
1384 		/*
1385 		 * Indirect branch instruction with subtype of
1386 		 * OCSD_S_INSTR_V7_IMPLIED_RET, this is explicit hint for
1387 		 * function return for A32/T32.
1388 		 */
1389 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1390 		    packet->last_instr_subtype == OCSD_S_INSTR_V7_IMPLIED_RET)
1391 			packet->flags = PERF_IP_FLAG_BRANCH |
1392 					PERF_IP_FLAG_RETURN;
1393 
1394 		/*
1395 		 * Indirect branch instruction without link (e.g. BR), usually
1396 		 * this is used for function return, especially for functions
1397 		 * within dynamic link lib.
1398 		 */
1399 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1400 		    packet->last_instr_subtype == OCSD_S_INSTR_NONE)
1401 			packet->flags = PERF_IP_FLAG_BRANCH |
1402 					PERF_IP_FLAG_RETURN;
1403 
1404 		/* Return instruction for function return. */
1405 		if (packet->last_instr_type == OCSD_INSTR_BR_INDIRECT &&
1406 		    packet->last_instr_subtype == OCSD_S_INSTR_V8_RET)
1407 			packet->flags = PERF_IP_FLAG_BRANCH |
1408 					PERF_IP_FLAG_RETURN;
1409 
1410 		/*
1411 		 * Decoder might insert a discontinuity in the middle of
1412 		 * instruction packets, fixup prev_packet with flag
1413 		 * PERF_IP_FLAG_TRACE_BEGIN to indicate restarting trace.
1414 		 */
1415 		if (prev_packet->sample_type == CS_ETM_DISCONTINUITY)
1416 			prev_packet->flags |= PERF_IP_FLAG_BRANCH |
1417 					      PERF_IP_FLAG_TRACE_BEGIN;
1418 
1419 		/*
1420 		 * If the previous packet is an exception return packet
1421 		 * and the return address just follows SVC instuction,
1422 		 * it needs to calibrate the previous packet sample flags
1423 		 * as PERF_IP_FLAG_SYSCALLRET.
1424 		 */
1425 		if (prev_packet->flags == (PERF_IP_FLAG_BRANCH |
1426 					   PERF_IP_FLAG_RETURN |
1427 					   PERF_IP_FLAG_INTERRUPT) &&
1428 		    cs_etm__is_svc_instr(etmq, packet, packet->start_addr))
1429 			prev_packet->flags = PERF_IP_FLAG_BRANCH |
1430 					     PERF_IP_FLAG_RETURN |
1431 					     PERF_IP_FLAG_SYSCALLRET;
1432 		break;
1433 	case CS_ETM_DISCONTINUITY:
1434 		/*
1435 		 * The trace is discontinuous, if the previous packet is
1436 		 * instruction packet, set flag PERF_IP_FLAG_TRACE_END
1437 		 * for previous packet.
1438 		 */
1439 		if (prev_packet->sample_type == CS_ETM_RANGE)
1440 			prev_packet->flags |= PERF_IP_FLAG_BRANCH |
1441 					      PERF_IP_FLAG_TRACE_END;
1442 		break;
1443 	case CS_ETM_EXCEPTION:
1444 		ret = cs_etm__get_magic(packet->trace_chan_id, &magic);
1445 		if (ret)
1446 			return ret;
1447 
1448 		/* The exception is for system call. */
1449 		if (cs_etm__is_syscall(etmq, magic))
1450 			packet->flags = PERF_IP_FLAG_BRANCH |
1451 					PERF_IP_FLAG_CALL |
1452 					PERF_IP_FLAG_SYSCALLRET;
1453 		/*
1454 		 * The exceptions are triggered by external signals from bus,
1455 		 * interrupt controller, debug module, PE reset or halt.
1456 		 */
1457 		else if (cs_etm__is_async_exception(etmq, magic))
1458 			packet->flags = PERF_IP_FLAG_BRANCH |
1459 					PERF_IP_FLAG_CALL |
1460 					PERF_IP_FLAG_ASYNC |
1461 					PERF_IP_FLAG_INTERRUPT;
1462 		/*
1463 		 * Otherwise, exception is caused by trap, instruction &
1464 		 * data fault, or alignment errors.
1465 		 */
1466 		else if (cs_etm__is_sync_exception(etmq, magic))
1467 			packet->flags = PERF_IP_FLAG_BRANCH |
1468 					PERF_IP_FLAG_CALL |
1469 					PERF_IP_FLAG_INTERRUPT;
1470 
1471 		/*
1472 		 * When the exception packet is inserted, since exception
1473 		 * packet is not used standalone for generating samples
1474 		 * and it's affiliation to the previous instruction range
1475 		 * packet; so set previous range packet flags to tell perf
1476 		 * it is an exception taken branch.
1477 		 */
1478 		if (prev_packet->sample_type == CS_ETM_RANGE)
1479 			prev_packet->flags = packet->flags;
1480 		break;
1481 	case CS_ETM_EXCEPTION_RET:
1482 		/*
1483 		 * When the exception return packet is inserted, since
1484 		 * exception return packet is not used standalone for
1485 		 * generating samples and it's affiliation to the previous
1486 		 * instruction range packet; so set previous range packet
1487 		 * flags to tell perf it is an exception return branch.
1488 		 *
1489 		 * The exception return can be for either system call or
1490 		 * other exception types; unfortunately the packet doesn't
1491 		 * contain exception type related info so we cannot decide
1492 		 * the exception type purely based on exception return packet.
1493 		 * If we record the exception number from exception packet and
1494 		 * reuse it for excpetion return packet, this is not reliable
1495 		 * due the trace can be discontinuity or the interrupt can
1496 		 * be nested, thus the recorded exception number cannot be
1497 		 * used for exception return packet for these two cases.
1498 		 *
1499 		 * For exception return packet, we only need to distinguish the
1500 		 * packet is for system call or for other types.  Thus the
1501 		 * decision can be deferred when receive the next packet which
1502 		 * contains the return address, based on the return address we
1503 		 * can read out the previous instruction and check if it's a
1504 		 * system call instruction and then calibrate the sample flag
1505 		 * as needed.
1506 		 */
1507 		if (prev_packet->sample_type == CS_ETM_RANGE)
1508 			prev_packet->flags = PERF_IP_FLAG_BRANCH |
1509 					     PERF_IP_FLAG_RETURN |
1510 					     PERF_IP_FLAG_INTERRUPT;
1511 		break;
1512 	case CS_ETM_EMPTY:
1513 	default:
1514 		break;
1515 	}
1516 
1517 	return 0;
1518 }
1519 
1520 static int cs_etm__decode_data_block(struct cs_etm_queue *etmq)
1521 {
1522 	int ret = 0;
1523 	size_t processed = 0;
1524 
1525 	/*
1526 	 * Packets are decoded and added to the decoder's packet queue
1527 	 * until the decoder packet processing callback has requested that
1528 	 * processing stops or there is nothing left in the buffer.  Normal
1529 	 * operations that stop processing are a timestamp packet or a full
1530 	 * decoder buffer queue.
1531 	 */
1532 	ret = cs_etm_decoder__process_data_block(etmq->decoder,
1533 						 etmq->offset,
1534 						 &etmq->buf[etmq->buf_used],
1535 						 etmq->buf_len,
1536 						 &processed);
1537 	if (ret)
1538 		goto out;
1539 
1540 	etmq->offset += processed;
1541 	etmq->buf_used += processed;
1542 	etmq->buf_len -= processed;
1543 
1544 out:
1545 	return ret;
1546 }
1547 
1548 static int cs_etm__process_decoder_queue(struct cs_etm_queue *etmq)
1549 {
1550 	int ret;
1551 
1552 		/* Process each packet in this chunk */
1553 		while (1) {
1554 			ret = cs_etm_decoder__get_packet(etmq->decoder,
1555 							 etmq->packet);
1556 			if (ret <= 0)
1557 				/*
1558 				 * Stop processing this chunk on
1559 				 * end of data or error
1560 				 */
1561 				break;
1562 
1563 			/*
1564 			 * Since packet addresses are swapped in packet
1565 			 * handling within below switch() statements,
1566 			 * thus setting sample flags must be called
1567 			 * prior to switch() statement to use address
1568 			 * information before packets swapping.
1569 			 */
1570 			ret = cs_etm__set_sample_flags(etmq);
1571 			if (ret < 0)
1572 				break;
1573 
1574 			switch (etmq->packet->sample_type) {
1575 			case CS_ETM_RANGE:
1576 				/*
1577 				 * If the packet contains an instruction
1578 				 * range, generate instruction sequence
1579 				 * events.
1580 				 */
1581 				cs_etm__sample(etmq);
1582 				break;
1583 			case CS_ETM_EXCEPTION:
1584 			case CS_ETM_EXCEPTION_RET:
1585 				/*
1586 				 * If the exception packet is coming,
1587 				 * make sure the previous instruction
1588 				 * range packet to be handled properly.
1589 				 */
1590 				cs_etm__exception(etmq);
1591 				break;
1592 			case CS_ETM_DISCONTINUITY:
1593 				/*
1594 				 * Discontinuity in trace, flush
1595 				 * previous branch stack
1596 				 */
1597 				cs_etm__flush(etmq);
1598 				break;
1599 			case CS_ETM_EMPTY:
1600 				/*
1601 				 * Should not receive empty packet,
1602 				 * report error.
1603 				 */
1604 				pr_err("CS ETM Trace: empty packet\n");
1605 				return -EINVAL;
1606 			default:
1607 				break;
1608 			}
1609 		}
1610 
1611 	return ret;
1612 }
1613 
1614 static int cs_etm__run_decoder(struct cs_etm_queue *etmq)
1615 {
1616 	int err = 0;
1617 
1618 	/* Go through each buffer in the queue and decode them one by one */
1619 	while (1) {
1620 		err = cs_etm__get_data_block(etmq);
1621 		if (err <= 0)
1622 			return err;
1623 
1624 		/* Run trace decoder until buffer consumed or end of trace */
1625 		do {
1626 			err = cs_etm__decode_data_block(etmq);
1627 			if (err)
1628 				return err;
1629 
1630 			/*
1631 			 * Process each packet in this chunk, nothing to do if
1632 			 * an error occurs other than hoping the next one will
1633 			 * be better.
1634 			 */
1635 			err = cs_etm__process_decoder_queue(etmq);
1636 
1637 		} while (etmq->buf_len);
1638 
1639 		if (err == 0)
1640 			/* Flush any remaining branch stack entries */
1641 			err = cs_etm__end_block(etmq);
1642 	}
1643 
1644 	return err;
1645 }
1646 
1647 static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
1648 					   pid_t tid)
1649 {
1650 	unsigned int i;
1651 	struct auxtrace_queues *queues = &etm->queues;
1652 
1653 	for (i = 0; i < queues->nr_queues; i++) {
1654 		struct auxtrace_queue *queue = &etm->queues.queue_array[i];
1655 		struct cs_etm_queue *etmq = queue->priv;
1656 
1657 		if (etmq && ((tid == -1) || (etmq->tid == tid))) {
1658 			cs_etm__set_pid_tid_cpu(etm, queue);
1659 			cs_etm__run_decoder(etmq);
1660 		}
1661 	}
1662 
1663 	return 0;
1664 }
1665 
1666 static int cs_etm__process_event(struct perf_session *session,
1667 				 union perf_event *event,
1668 				 struct perf_sample *sample,
1669 				 struct perf_tool *tool)
1670 {
1671 	int err = 0;
1672 	u64 timestamp;
1673 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
1674 						   struct cs_etm_auxtrace,
1675 						   auxtrace);
1676 
1677 	if (dump_trace)
1678 		return 0;
1679 
1680 	if (!tool->ordered_events) {
1681 		pr_err("CoreSight ETM Trace requires ordered events\n");
1682 		return -EINVAL;
1683 	}
1684 
1685 	if (!etm->timeless_decoding)
1686 		return -EINVAL;
1687 
1688 	if (sample->time && (sample->time != (u64) -1))
1689 		timestamp = sample->time;
1690 	else
1691 		timestamp = 0;
1692 
1693 	if (timestamp || etm->timeless_decoding) {
1694 		err = cs_etm__update_queues(etm);
1695 		if (err)
1696 			return err;
1697 	}
1698 
1699 	if (event->header.type == PERF_RECORD_EXIT)
1700 		return cs_etm__process_timeless_queues(etm,
1701 						       event->fork.tid);
1702 
1703 	return 0;
1704 }
1705 
1706 static int cs_etm__process_auxtrace_event(struct perf_session *session,
1707 					  union perf_event *event,
1708 					  struct perf_tool *tool __maybe_unused)
1709 {
1710 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
1711 						   struct cs_etm_auxtrace,
1712 						   auxtrace);
1713 	if (!etm->data_queued) {
1714 		struct auxtrace_buffer *buffer;
1715 		off_t  data_offset;
1716 		int fd = perf_data__fd(session->data);
1717 		bool is_pipe = perf_data__is_pipe(session->data);
1718 		int err;
1719 
1720 		if (is_pipe)
1721 			data_offset = 0;
1722 		else {
1723 			data_offset = lseek(fd, 0, SEEK_CUR);
1724 			if (data_offset == -1)
1725 				return -errno;
1726 		}
1727 
1728 		err = auxtrace_queues__add_event(&etm->queues, session,
1729 						 event, data_offset, &buffer);
1730 		if (err)
1731 			return err;
1732 
1733 		if (dump_trace)
1734 			if (auxtrace_buffer__get_data(buffer, fd)) {
1735 				cs_etm__dump_event(etm, buffer);
1736 				auxtrace_buffer__put_data(buffer);
1737 			}
1738 	}
1739 
1740 	return 0;
1741 }
1742 
1743 static bool cs_etm__is_timeless_decoding(struct cs_etm_auxtrace *etm)
1744 {
1745 	struct perf_evsel *evsel;
1746 	struct perf_evlist *evlist = etm->session->evlist;
1747 	bool timeless_decoding = true;
1748 
1749 	/*
1750 	 * Circle through the list of event and complain if we find one
1751 	 * with the time bit set.
1752 	 */
1753 	evlist__for_each_entry(evlist, evsel) {
1754 		if ((evsel->attr.sample_type & PERF_SAMPLE_TIME))
1755 			timeless_decoding = false;
1756 	}
1757 
1758 	return timeless_decoding;
1759 }
1760 
1761 static const char * const cs_etm_global_header_fmts[] = {
1762 	[CS_HEADER_VERSION_0]	= "	Header version		       %llx\n",
1763 	[CS_PMU_TYPE_CPUS]	= "	PMU type/num cpus	       %llx\n",
1764 	[CS_ETM_SNAPSHOT]	= "	Snapshot		       %llx\n",
1765 };
1766 
1767 static const char * const cs_etm_priv_fmts[] = {
1768 	[CS_ETM_MAGIC]		= "	Magic number		       %llx\n",
1769 	[CS_ETM_CPU]		= "	CPU			       %lld\n",
1770 	[CS_ETM_ETMCR]		= "	ETMCR			       %llx\n",
1771 	[CS_ETM_ETMTRACEIDR]	= "	ETMTRACEIDR		       %llx\n",
1772 	[CS_ETM_ETMCCER]	= "	ETMCCER			       %llx\n",
1773 	[CS_ETM_ETMIDR]		= "	ETMIDR			       %llx\n",
1774 };
1775 
1776 static const char * const cs_etmv4_priv_fmts[] = {
1777 	[CS_ETM_MAGIC]		= "	Magic number		       %llx\n",
1778 	[CS_ETM_CPU]		= "	CPU			       %lld\n",
1779 	[CS_ETMV4_TRCCONFIGR]	= "	TRCCONFIGR		       %llx\n",
1780 	[CS_ETMV4_TRCTRACEIDR]	= "	TRCTRACEIDR		       %llx\n",
1781 	[CS_ETMV4_TRCIDR0]	= "	TRCIDR0			       %llx\n",
1782 	[CS_ETMV4_TRCIDR1]	= "	TRCIDR1			       %llx\n",
1783 	[CS_ETMV4_TRCIDR2]	= "	TRCIDR2			       %llx\n",
1784 	[CS_ETMV4_TRCIDR8]	= "	TRCIDR8			       %llx\n",
1785 	[CS_ETMV4_TRCAUTHSTATUS] = "	TRCAUTHSTATUS		       %llx\n",
1786 };
1787 
1788 static void cs_etm__print_auxtrace_info(u64 *val, int num)
1789 {
1790 	int i, j, cpu = 0;
1791 
1792 	for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
1793 		fprintf(stdout, cs_etm_global_header_fmts[i], val[i]);
1794 
1795 	for (i = CS_HEADER_VERSION_0_MAX; cpu < num; cpu++) {
1796 		if (val[i] == __perf_cs_etmv3_magic)
1797 			for (j = 0; j < CS_ETM_PRIV_MAX; j++, i++)
1798 				fprintf(stdout, cs_etm_priv_fmts[j], val[i]);
1799 		else if (val[i] == __perf_cs_etmv4_magic)
1800 			for (j = 0; j < CS_ETMV4_PRIV_MAX; j++, i++)
1801 				fprintf(stdout, cs_etmv4_priv_fmts[j], val[i]);
1802 		else
1803 			/* failure.. return */
1804 			return;
1805 	}
1806 }
1807 
1808 int cs_etm__process_auxtrace_info(union perf_event *event,
1809 				  struct perf_session *session)
1810 {
1811 	struct auxtrace_info_event *auxtrace_info = &event->auxtrace_info;
1812 	struct cs_etm_auxtrace *etm = NULL;
1813 	struct int_node *inode;
1814 	unsigned int pmu_type;
1815 	int event_header_size = sizeof(struct perf_event_header);
1816 	int info_header_size;
1817 	int total_size = auxtrace_info->header.size;
1818 	int priv_size = 0;
1819 	int num_cpu;
1820 	int err = 0, idx = -1;
1821 	int i, j, k;
1822 	u64 *ptr, *hdr = NULL;
1823 	u64 **metadata = NULL;
1824 
1825 	/*
1826 	 * sizeof(auxtrace_info_event::type) +
1827 	 * sizeof(auxtrace_info_event::reserved) == 8
1828 	 */
1829 	info_header_size = 8;
1830 
1831 	if (total_size < (event_header_size + info_header_size))
1832 		return -EINVAL;
1833 
1834 	priv_size = total_size - event_header_size - info_header_size;
1835 
1836 	/* First the global part */
1837 	ptr = (u64 *) auxtrace_info->priv;
1838 
1839 	/* Look for version '0' of the header */
1840 	if (ptr[0] != 0)
1841 		return -EINVAL;
1842 
1843 	hdr = zalloc(sizeof(*hdr) * CS_HEADER_VERSION_0_MAX);
1844 	if (!hdr)
1845 		return -ENOMEM;
1846 
1847 	/* Extract header information - see cs-etm.h for format */
1848 	for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
1849 		hdr[i] = ptr[i];
1850 	num_cpu = hdr[CS_PMU_TYPE_CPUS] & 0xffffffff;
1851 	pmu_type = (unsigned int) ((hdr[CS_PMU_TYPE_CPUS] >> 32) &
1852 				    0xffffffff);
1853 
1854 	/*
1855 	 * Create an RB tree for traceID-metadata tuple.  Since the conversion
1856 	 * has to be made for each packet that gets decoded, optimizing access
1857 	 * in anything other than a sequential array is worth doing.
1858 	 */
1859 	traceid_list = intlist__new(NULL);
1860 	if (!traceid_list) {
1861 		err = -ENOMEM;
1862 		goto err_free_hdr;
1863 	}
1864 
1865 	metadata = zalloc(sizeof(*metadata) * num_cpu);
1866 	if (!metadata) {
1867 		err = -ENOMEM;
1868 		goto err_free_traceid_list;
1869 	}
1870 
1871 	/*
1872 	 * The metadata is stored in the auxtrace_info section and encodes
1873 	 * the configuration of the ARM embedded trace macrocell which is
1874 	 * required by the trace decoder to properly decode the trace due
1875 	 * to its highly compressed nature.
1876 	 */
1877 	for (j = 0; j < num_cpu; j++) {
1878 		if (ptr[i] == __perf_cs_etmv3_magic) {
1879 			metadata[j] = zalloc(sizeof(*metadata[j]) *
1880 					     CS_ETM_PRIV_MAX);
1881 			if (!metadata[j]) {
1882 				err = -ENOMEM;
1883 				goto err_free_metadata;
1884 			}
1885 			for (k = 0; k < CS_ETM_PRIV_MAX; k++)
1886 				metadata[j][k] = ptr[i + k];
1887 
1888 			/* The traceID is our handle */
1889 			idx = metadata[j][CS_ETM_ETMTRACEIDR];
1890 			i += CS_ETM_PRIV_MAX;
1891 		} else if (ptr[i] == __perf_cs_etmv4_magic) {
1892 			metadata[j] = zalloc(sizeof(*metadata[j]) *
1893 					     CS_ETMV4_PRIV_MAX);
1894 			if (!metadata[j]) {
1895 				err = -ENOMEM;
1896 				goto err_free_metadata;
1897 			}
1898 			for (k = 0; k < CS_ETMV4_PRIV_MAX; k++)
1899 				metadata[j][k] = ptr[i + k];
1900 
1901 			/* The traceID is our handle */
1902 			idx = metadata[j][CS_ETMV4_TRCTRACEIDR];
1903 			i += CS_ETMV4_PRIV_MAX;
1904 		}
1905 
1906 		/* Get an RB node for this CPU */
1907 		inode = intlist__findnew(traceid_list, idx);
1908 
1909 		/* Something went wrong, no need to continue */
1910 		if (!inode) {
1911 			err = PTR_ERR(inode);
1912 			goto err_free_metadata;
1913 		}
1914 
1915 		/*
1916 		 * The node for that CPU should not be taken.
1917 		 * Back out if that's the case.
1918 		 */
1919 		if (inode->priv) {
1920 			err = -EINVAL;
1921 			goto err_free_metadata;
1922 		}
1923 		/* All good, associate the traceID with the metadata pointer */
1924 		inode->priv = metadata[j];
1925 	}
1926 
1927 	/*
1928 	 * Each of CS_HEADER_VERSION_0_MAX, CS_ETM_PRIV_MAX and
1929 	 * CS_ETMV4_PRIV_MAX mark how many double words are in the
1930 	 * global metadata, and each cpu's metadata respectively.
1931 	 * The following tests if the correct number of double words was
1932 	 * present in the auxtrace info section.
1933 	 */
1934 	if (i * 8 != priv_size) {
1935 		err = -EINVAL;
1936 		goto err_free_metadata;
1937 	}
1938 
1939 	etm = zalloc(sizeof(*etm));
1940 
1941 	if (!etm) {
1942 		err = -ENOMEM;
1943 		goto err_free_metadata;
1944 	}
1945 
1946 	err = auxtrace_queues__init(&etm->queues);
1947 	if (err)
1948 		goto err_free_etm;
1949 
1950 	etm->session = session;
1951 	etm->machine = &session->machines.host;
1952 
1953 	etm->num_cpu = num_cpu;
1954 	etm->pmu_type = pmu_type;
1955 	etm->snapshot_mode = (hdr[CS_ETM_SNAPSHOT] != 0);
1956 	etm->metadata = metadata;
1957 	etm->auxtrace_type = auxtrace_info->type;
1958 	etm->timeless_decoding = cs_etm__is_timeless_decoding(etm);
1959 
1960 	etm->auxtrace.process_event = cs_etm__process_event;
1961 	etm->auxtrace.process_auxtrace_event = cs_etm__process_auxtrace_event;
1962 	etm->auxtrace.flush_events = cs_etm__flush_events;
1963 	etm->auxtrace.free_events = cs_etm__free_events;
1964 	etm->auxtrace.free = cs_etm__free;
1965 	session->auxtrace = &etm->auxtrace;
1966 
1967 	etm->unknown_thread = thread__new(999999999, 999999999);
1968 	if (!etm->unknown_thread)
1969 		goto err_free_queues;
1970 
1971 	/*
1972 	 * Initialize list node so that at thread__zput() we can avoid
1973 	 * segmentation fault at list_del_init().
1974 	 */
1975 	INIT_LIST_HEAD(&etm->unknown_thread->node);
1976 
1977 	err = thread__set_comm(etm->unknown_thread, "unknown", 0);
1978 	if (err)
1979 		goto err_delete_thread;
1980 
1981 	if (thread__init_map_groups(etm->unknown_thread, etm->machine))
1982 		goto err_delete_thread;
1983 
1984 	if (dump_trace) {
1985 		cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
1986 		return 0;
1987 	}
1988 
1989 	if (session->itrace_synth_opts && session->itrace_synth_opts->set) {
1990 		etm->synth_opts = *session->itrace_synth_opts;
1991 	} else {
1992 		itrace_synth_opts__set_default(&etm->synth_opts,
1993 				session->itrace_synth_opts->default_no_sample);
1994 		etm->synth_opts.callchain = false;
1995 	}
1996 
1997 	err = cs_etm__synth_events(etm, session);
1998 	if (err)
1999 		goto err_delete_thread;
2000 
2001 	err = auxtrace_queues__process_index(&etm->queues, session);
2002 	if (err)
2003 		goto err_delete_thread;
2004 
2005 	etm->data_queued = etm->queues.populated;
2006 
2007 	return 0;
2008 
2009 err_delete_thread:
2010 	thread__zput(etm->unknown_thread);
2011 err_free_queues:
2012 	auxtrace_queues__free(&etm->queues);
2013 	session->auxtrace = NULL;
2014 err_free_etm:
2015 	zfree(&etm);
2016 err_free_metadata:
2017 	/* No need to check @metadata[j], free(NULL) is supported */
2018 	for (j = 0; j < num_cpu; j++)
2019 		free(metadata[j]);
2020 	zfree(&metadata);
2021 err_free_traceid_list:
2022 	intlist__delete(traceid_list);
2023 err_free_hdr:
2024 	zfree(&hdr);
2025 
2026 	return -EINVAL;
2027 }
2028