1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * auxtrace.h: AUX area trace support
4 * Copyright (c) 2013-2015, Intel Corporation.
7 #ifndef __PERF_AUXTRACE_H
8 #define __PERF_AUXTRACE_H
10 #include <sys/types.h>
14 #include <stdio.h> // FILE
15 #include <linux/list.h>
16 #include <linux/perf_event.h>
17 #include <linux/types.h>
18 #include <asm/bitsperlong.h>
19 #include <asm/barrier.h>
30 struct perf_record_auxtrace_error;
31 struct perf_record_auxtrace_info;
35 enum auxtrace_error_type {
36 PERF_AUXTRACE_ERROR_ITRACE = 1,
37 PERF_AUXTRACE_ERROR_MAX
40 /* Auxtrace records must have the same alignment as perf event records */
41 #define PERF_AUXTRACE_RECORD_ALIGNMENT 8
44 PERF_AUXTRACE_UNKNOWN,
45 PERF_AUXTRACE_INTEL_PT,
46 PERF_AUXTRACE_INTEL_BTS,
48 PERF_AUXTRACE_ARM_SPE,
49 PERF_AUXTRACE_S390_CPUMSF,
52 enum itrace_period_type {
53 PERF_ITRACE_PERIOD_INSTRUCTIONS,
54 PERF_ITRACE_PERIOD_TICKS,
55 PERF_ITRACE_PERIOD_NANOSECS,
59 * struct itrace_synth_opts - AUX area tracing synthesis options.
60 * @set: indicates whether or not options have been set
61 * @default_no_sample: Default to no sampling.
62 * @inject: indicates the event (not just the sample) must be fully synthesized
63 * because 'perf inject' will write it out
64 * @instructions: whether to synthesize 'instructions' events
65 * @branches: whether to synthesize 'branches' events
66 * @transactions: whether to synthesize events for transactions
67 * @ptwrites: whether to synthesize events for ptwrites
68 * @pwr_events: whether to synthesize power events
69 * @other_events: whether to synthesize other events recorded due to the use of
71 * @errors: whether to synthesize decoder error events
72 * @dont_decode: whether to skip decoding entirely
73 * @log: write a decoding log
74 * @calls: limit branch samples to calls (can be combined with @returns)
75 * @returns: limit branch samples to returns (can be combined with @calls)
76 * @callchain: add callchain to 'instructions' events
77 * @add_callchain: add callchain to existing event records
78 * @thread_stack: feed branches to the thread_stack
79 * @last_branch: add branch context to 'instruction' events
80 * @add_last_branch: add branch context to existing event records
81 * @callchain_sz: maximum callchain size
82 * @last_branch_sz: branch context size
83 * @period: 'instructions' events period
84 * @period_type: 'instructions' events period type
85 * @initial_skip: skip N events at the beginning.
86 * @cpu_bitmap: CPUs for which to synthesize events, or NULL for all
87 * @ptime_range: time intervals to trace or NULL
88 * @range_num: number of time intervals to trace
90 struct itrace_synth_opts {
92 bool default_no_sample;
109 bool add_last_branch;
110 unsigned int callchain_sz;
111 unsigned int last_branch_sz;
112 unsigned long long period;
113 enum itrace_period_type period_type;
114 unsigned long initial_skip;
115 unsigned long *cpu_bitmap;
116 struct perf_time_interval *ptime_range;
121 * struct auxtrace_index_entry - indexes a AUX area tracing event within a
123 * @file_offset: offset within the perf.data file
124 * @sz: size of the event
126 struct auxtrace_index_entry {
131 #define PERF_AUXTRACE_INDEX_ENTRY_COUNT 256
134 * struct auxtrace_index - index of AUX area tracing events within a perf.data
136 * @list: linking a number of arrays of entries
137 * @nr: number of entries
138 * @entries: array of entries
140 struct auxtrace_index {
141 struct list_head list;
143 struct auxtrace_index_entry entries[PERF_AUXTRACE_INDEX_ENTRY_COUNT];
147 * struct auxtrace - session callbacks to allow AUX area data decoding.
148 * @process_event: lets the decoder see all session events
149 * @process_auxtrace_event: process a PERF_RECORD_AUXTRACE event
150 * @queue_data: queue an AUX sample or PERF_RECORD_AUXTRACE event for later
152 * @dump_auxtrace_sample: dump AUX area sample data
153 * @flush_events: process any remaining data
154 * @free_events: free resources associated with event processing
155 * @free: free resources associated with the session
158 int (*process_event)(struct perf_session *session,
159 union perf_event *event,
160 struct perf_sample *sample,
161 struct perf_tool *tool);
162 int (*process_auxtrace_event)(struct perf_session *session,
163 union perf_event *event,
164 struct perf_tool *tool);
165 int (*queue_data)(struct perf_session *session,
166 struct perf_sample *sample, union perf_event *event,
168 void (*dump_auxtrace_sample)(struct perf_session *session,
169 struct perf_sample *sample);
170 int (*flush_events)(struct perf_session *session,
171 struct perf_tool *tool);
172 void (*free_events)(struct perf_session *session);
173 void (*free)(struct perf_session *session);
174 bool (*evsel_is_auxtrace)(struct perf_session *session,
175 struct evsel *evsel);
179 * struct auxtrace_buffer - a buffer containing AUX area tracing data.
180 * @list: buffers are queued in a list held by struct auxtrace_queue
181 * @size: size of the buffer in bytes
182 * @pid: in per-thread mode, the pid this buffer is associated with
183 * @tid: in per-thread mode, the tid this buffer is associated with
184 * @cpu: in per-cpu mode, the cpu this buffer is associated with
185 * @data: actual buffer data (can be null if the data has not been loaded)
186 * @data_offset: file offset at which the buffer can be read
187 * @mmap_addr: mmap address at which the buffer can be read
188 * @mmap_size: size of the mmap at @mmap_addr
189 * @data_needs_freeing: @data was malloc'd so free it when it is no longer
191 * @consecutive: the original data was split up and this buffer is consecutive
192 * to the previous buffer
193 * @offset: offset as determined by aux_head / aux_tail members of struct
194 * perf_event_mmap_page
195 * @reference: an implementation-specific reference determined when the data is
197 * @buffer_nr: used to number each buffer
198 * @use_size: implementation actually only uses this number of bytes
199 * @use_data: implementation actually only uses data starting at this address
201 struct auxtrace_buffer {
202 struct list_head list;
211 bool data_needs_freeing;
221 * struct auxtrace_queue - a queue of AUX area tracing data buffers.
222 * @head: head of buffer list
223 * @tid: in per-thread mode, the tid this queue is associated with
224 * @cpu: in per-cpu mode, the cpu this queue is associated with
225 * @set: %true once this queue has been dedicated to a specific thread or cpu
226 * @priv: implementation-specific data
228 struct auxtrace_queue {
229 struct list_head head;
237 * struct auxtrace_queues - an array of AUX area tracing queues.
238 * @queue_array: array of queues
239 * @nr_queues: number of queues
240 * @new_data: set whenever new data is queued
241 * @populated: queues have been fully populated using the auxtrace_index
242 * @next_buffer_nr: used to number each buffer
244 struct auxtrace_queues {
245 struct auxtrace_queue *queue_array;
246 unsigned int nr_queues;
253 * struct auxtrace_heap_item - element of struct auxtrace_heap.
254 * @queue_nr: queue number
255 * @ordinal: value used for sorting (lowest ordinal is top of the heap) expected
258 struct auxtrace_heap_item {
259 unsigned int queue_nr;
264 * struct auxtrace_heap - a heap suitable for sorting AUX area tracing queues.
265 * @heap_array: the heap
266 * @heap_cnt: the number of elements in the heap
267 * @heap_sz: maximum number of elements (grows as needed)
269 struct auxtrace_heap {
270 struct auxtrace_heap_item *heap_array;
271 unsigned int heap_cnt;
272 unsigned int heap_sz;
276 * struct auxtrace_mmap - records an mmap of the auxtrace buffer.
277 * @base: address of mapped area
278 * @userpg: pointer to buffer's perf_event_mmap_page
279 * @mask: %0 if @len is not a power of two, otherwise (@len - %1)
280 * @len: size of mapped area
281 * @prev: previous aux_head
282 * @idx: index of this mmap
283 * @tid: tid for a per-thread mmap (also set if there is only 1 tid on a per-cpu
285 * @cpu: cpu number for a per-cpu mmap otherwise %-1
287 struct auxtrace_mmap {
299 * struct auxtrace_mmap_params - parameters to set up struct auxtrace_mmap.
300 * @mask: %0 if @len is not a power of two, otherwise (@len - %1)
301 * @offset: file offset of mapped area
302 * @len: size of mapped area
303 * @prot: mmap memory protection
304 * @idx: index of this mmap
305 * @tid: tid for a per-thread mmap (also set if there is only 1 tid on a per-cpu
307 * @cpu: cpu number for a per-cpu mmap otherwise %-1
309 struct auxtrace_mmap_params {
320 * struct auxtrace_record - callbacks for recording AUX area data.
321 * @recording_options: validate and process recording options
322 * @info_priv_size: return the size of the private data in auxtrace_info_event
323 * @info_fill: fill-in the private data in auxtrace_info_event
324 * @free: free this auxtrace record structure
325 * @snapshot_start: starting a snapshot
326 * @snapshot_finish: finishing a snapshot
327 * @find_snapshot: find data to snapshot within auxtrace mmap
328 * @parse_snapshot_options: parse snapshot options
329 * @reference: provide a 64-bit reference number for auxtrace_event
330 * @read_finish: called after reading from an auxtrace mmap
331 * @alignment: alignment (if any) for AUX area data
332 * @default_aux_sample_size: default sample size for --aux sample option
333 * @pmu: associated pmu
334 * @evlist: selected events list
336 struct auxtrace_record {
337 int (*recording_options)(struct auxtrace_record *itr,
338 struct evlist *evlist,
339 struct record_opts *opts);
340 size_t (*info_priv_size)(struct auxtrace_record *itr,
341 struct evlist *evlist);
342 int (*info_fill)(struct auxtrace_record *itr,
343 struct perf_session *session,
344 struct perf_record_auxtrace_info *auxtrace_info,
346 void (*free)(struct auxtrace_record *itr);
347 int (*snapshot_start)(struct auxtrace_record *itr);
348 int (*snapshot_finish)(struct auxtrace_record *itr);
349 int (*find_snapshot)(struct auxtrace_record *itr, int idx,
350 struct auxtrace_mmap *mm, unsigned char *data,
351 u64 *head, u64 *old);
352 int (*parse_snapshot_options)(struct auxtrace_record *itr,
353 struct record_opts *opts,
355 u64 (*reference)(struct auxtrace_record *itr);
356 int (*read_finish)(struct auxtrace_record *itr, int idx);
357 unsigned int alignment;
358 unsigned int default_aux_sample_size;
359 struct perf_pmu *pmu;
360 struct evlist *evlist;
364 * struct addr_filter - address filter.
366 * @range: true if it is a range filter
367 * @start: true if action is 'filter' or 'start'
368 * @action: 'filter', 'start' or 'stop' ('tracestop' is accepted but converted
370 * @sym_from: symbol name for the filter address
371 * @sym_to: symbol name that determines the filter size
372 * @sym_from_idx: selects n'th from symbols with the same name (0 means global
373 * and less than 0 means symbol must be unique)
374 * @sym_to_idx: same as @sym_from_idx but for @sym_to
375 * @addr: filter address
376 * @size: filter region size (for range filters)
377 * @filename: DSO file name or NULL for the kernel
378 * @str: allocated string that contains the other string members
381 struct list_head list;
385 const char *sym_from;
391 const char *filename;
396 * struct addr_filters - list of address filters.
397 * @head: list of address filters
398 * @cnt: number of address filters
400 struct addr_filters {
401 struct list_head head;
405 struct auxtrace_cache;
407 #ifdef HAVE_AUXTRACE_SUPPORT
410 * In snapshot mode the mmapped page is read-only which makes using
411 * __sync_val_compare_and_swap() problematic. However, snapshot mode expects
412 * the buffer is not updated while the snapshot is made (e.g. Intel PT disables
413 * the event) so there is not a race anyway.
415 static inline u64 auxtrace_mmap__read_snapshot_head(struct auxtrace_mmap *mm)
417 struct perf_event_mmap_page *pc = mm->userpg;
418 u64 head = READ_ONCE(pc->aux_head);
420 /* Ensure all reads are done after we read the head */
425 static inline u64 auxtrace_mmap__read_head(struct auxtrace_mmap *mm)
427 struct perf_event_mmap_page *pc = mm->userpg;
428 #if BITS_PER_LONG == 64 || !defined(HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT)
429 u64 head = READ_ONCE(pc->aux_head);
431 u64 head = __sync_val_compare_and_swap(&pc->aux_head, 0, 0);
434 /* Ensure all reads are done after we read the head */
439 static inline void auxtrace_mmap__write_tail(struct auxtrace_mmap *mm, u64 tail)
441 struct perf_event_mmap_page *pc = mm->userpg;
442 #if BITS_PER_LONG != 64 && defined(HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT)
446 /* Ensure all reads are done before we write the tail out */
448 #if BITS_PER_LONG == 64 || !defined(HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT)
452 old_tail = __sync_val_compare_and_swap(&pc->aux_tail, 0, 0);
453 } while (!__sync_bool_compare_and_swap(&pc->aux_tail, old_tail, tail));
457 int auxtrace_mmap__mmap(struct auxtrace_mmap *mm,
458 struct auxtrace_mmap_params *mp,
459 void *userpg, int fd);
460 void auxtrace_mmap__munmap(struct auxtrace_mmap *mm);
461 void auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp,
462 off_t auxtrace_offset,
463 unsigned int auxtrace_pages,
464 bool auxtrace_overwrite);
465 void auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp,
466 struct evlist *evlist, int idx,
469 typedef int (*process_auxtrace_t)(struct perf_tool *tool,
471 union perf_event *event, void *data1,
472 size_t len1, void *data2, size_t len2);
474 int auxtrace_mmap__read(struct mmap *map, struct auxtrace_record *itr,
475 struct perf_tool *tool, process_auxtrace_t fn);
477 int auxtrace_mmap__read_snapshot(struct mmap *map,
478 struct auxtrace_record *itr,
479 struct perf_tool *tool, process_auxtrace_t fn,
480 size_t snapshot_size);
482 int auxtrace_queues__init(struct auxtrace_queues *queues);
483 int auxtrace_queues__add_event(struct auxtrace_queues *queues,
484 struct perf_session *session,
485 union perf_event *event, off_t data_offset,
486 struct auxtrace_buffer **buffer_ptr);
487 struct auxtrace_queue *
488 auxtrace_queues__sample_queue(struct auxtrace_queues *queues,
489 struct perf_sample *sample,
490 struct perf_session *session);
491 int auxtrace_queues__add_sample(struct auxtrace_queues *queues,
492 struct perf_session *session,
493 struct perf_sample *sample, u64 data_offset,
495 void auxtrace_queues__free(struct auxtrace_queues *queues);
496 int auxtrace_queues__process_index(struct auxtrace_queues *queues,
497 struct perf_session *session);
498 int auxtrace_queue_data(struct perf_session *session, bool samples,
500 struct auxtrace_buffer *auxtrace_buffer__next(struct auxtrace_queue *queue,
501 struct auxtrace_buffer *buffer);
502 void *auxtrace_buffer__get_data(struct auxtrace_buffer *buffer, int fd);
503 void auxtrace_buffer__put_data(struct auxtrace_buffer *buffer);
504 void auxtrace_buffer__drop_data(struct auxtrace_buffer *buffer);
505 void auxtrace_buffer__free(struct auxtrace_buffer *buffer);
507 int auxtrace_heap__add(struct auxtrace_heap *heap, unsigned int queue_nr,
509 void auxtrace_heap__pop(struct auxtrace_heap *heap);
510 void auxtrace_heap__free(struct auxtrace_heap *heap);
512 struct auxtrace_cache_entry {
513 struct hlist_node hash;
517 struct auxtrace_cache *auxtrace_cache__new(unsigned int bits, size_t entry_size,
518 unsigned int limit_percent);
519 void auxtrace_cache__free(struct auxtrace_cache *auxtrace_cache);
520 void *auxtrace_cache__alloc_entry(struct auxtrace_cache *c);
521 void auxtrace_cache__free_entry(struct auxtrace_cache *c, void *entry);
522 int auxtrace_cache__add(struct auxtrace_cache *c, u32 key,
523 struct auxtrace_cache_entry *entry);
524 void auxtrace_cache__remove(struct auxtrace_cache *c, u32 key);
525 void *auxtrace_cache__lookup(struct auxtrace_cache *c, u32 key);
527 struct auxtrace_record *auxtrace_record__init(struct evlist *evlist,
530 int auxtrace_parse_snapshot_options(struct auxtrace_record *itr,
531 struct record_opts *opts,
533 int auxtrace_parse_sample_options(struct auxtrace_record *itr,
534 struct evlist *evlist,
535 struct record_opts *opts, const char *str);
536 int auxtrace_record__options(struct auxtrace_record *itr,
537 struct evlist *evlist,
538 struct record_opts *opts);
539 size_t auxtrace_record__info_priv_size(struct auxtrace_record *itr,
540 struct evlist *evlist);
541 int auxtrace_record__info_fill(struct auxtrace_record *itr,
542 struct perf_session *session,
543 struct perf_record_auxtrace_info *auxtrace_info,
545 void auxtrace_record__free(struct auxtrace_record *itr);
546 int auxtrace_record__snapshot_start(struct auxtrace_record *itr);
547 int auxtrace_record__snapshot_finish(struct auxtrace_record *itr, bool on_exit);
548 int auxtrace_record__find_snapshot(struct auxtrace_record *itr, int idx,
549 struct auxtrace_mmap *mm,
550 unsigned char *data, u64 *head, u64 *old);
551 u64 auxtrace_record__reference(struct auxtrace_record *itr);
552 int auxtrace_record__read_finish(struct auxtrace_record *itr, int idx);
554 int auxtrace_index__auxtrace_event(struct list_head *head, union perf_event *event,
556 int auxtrace_index__write(int fd, struct list_head *head);
557 int auxtrace_index__process(int fd, u64 size, struct perf_session *session,
559 void auxtrace_index__free(struct list_head *head);
561 void auxtrace_synth_error(struct perf_record_auxtrace_error *auxtrace_error, int type,
562 int code, int cpu, pid_t pid, pid_t tid, u64 ip,
563 const char *msg, u64 timestamp);
565 int perf_event__process_auxtrace_info(struct perf_session *session,
566 union perf_event *event);
567 s64 perf_event__process_auxtrace(struct perf_session *session,
568 union perf_event *event);
569 int perf_event__process_auxtrace_error(struct perf_session *session,
570 union perf_event *event);
571 int itrace_parse_synth_opts(const struct option *opt, const char *str,
573 void itrace_synth_opts__set_default(struct itrace_synth_opts *synth_opts,
576 size_t perf_event__fprintf_auxtrace_error(union perf_event *event, FILE *fp);
577 void perf_session__auxtrace_error_inc(struct perf_session *session,
578 union perf_event *event);
579 void events_stats__auxtrace_error_warn(const struct events_stats *stats);
581 void addr_filters__init(struct addr_filters *filts);
582 void addr_filters__exit(struct addr_filters *filts);
583 int addr_filters__parse_bare_filter(struct addr_filters *filts,
585 int auxtrace_parse_filters(struct evlist *evlist);
587 int auxtrace__process_event(struct perf_session *session, union perf_event *event,
588 struct perf_sample *sample, struct perf_tool *tool);
589 void auxtrace__dump_auxtrace_sample(struct perf_session *session,
590 struct perf_sample *sample);
591 int auxtrace__flush_events(struct perf_session *session, struct perf_tool *tool);
592 void auxtrace__free_events(struct perf_session *session);
593 void auxtrace__free(struct perf_session *session);
594 bool auxtrace__evsel_is_auxtrace(struct perf_session *session,
595 struct evsel *evsel);
597 #define ITRACE_HELP \
598 " i: synthesize instructions events\n" \
599 " b: synthesize branches events\n" \
600 " c: synthesize branches events (calls only)\n" \
601 " r: synthesize branches events (returns only)\n" \
602 " x: synthesize transactions events\n" \
603 " w: synthesize ptwrite events\n" \
604 " p: synthesize power events\n" \
605 " e: synthesize error events\n" \
606 " d: create a debug log\n" \
607 " g[len]: synthesize a call chain (use with i or x)\n" \
608 " l[len]: synthesize last branch entries (use with i or x)\n" \
609 " sNUMBER: skip initial number of events\n" \
610 " PERIOD[ns|us|ms|i|t]: specify period to sample stream\n" \
611 " concatenate multiple options. Default is ibxwpe or cewp\n"
614 void itrace_synth_opts__set_time_range(struct itrace_synth_opts *opts,
615 struct perf_time_interval *ptime_range,
618 opts->ptime_range = ptime_range;
619 opts->range_num = range_num;
623 void itrace_synth_opts__clear_time_range(struct itrace_synth_opts *opts)
625 opts->ptime_range = NULL;
632 static inline struct auxtrace_record *
633 auxtrace_record__init(struct evlist *evlist __maybe_unused,
641 void auxtrace_record__free(struct auxtrace_record *itr __maybe_unused)
646 int auxtrace_record__options(struct auxtrace_record *itr __maybe_unused,
647 struct evlist *evlist __maybe_unused,
648 struct record_opts *opts __maybe_unused)
653 #define perf_event__process_auxtrace_info 0
654 #define perf_event__process_auxtrace 0
655 #define perf_event__process_auxtrace_error 0
658 void perf_session__auxtrace_error_inc(struct perf_session *session
660 union perf_event *event
666 void events_stats__auxtrace_error_warn(const struct events_stats *stats
672 int itrace_parse_synth_opts(const struct option *opt __maybe_unused,
673 const char *str __maybe_unused,
674 int unset __maybe_unused)
676 pr_err("AUX area tracing not supported\n");
681 int auxtrace_parse_snapshot_options(struct auxtrace_record *itr __maybe_unused,
682 struct record_opts *opts __maybe_unused,
687 pr_err("AUX area tracing not supported\n");
692 int auxtrace_parse_sample_options(struct auxtrace_record *itr __maybe_unused,
693 struct evlist *evlist __maybe_unused,
694 struct record_opts *opts __maybe_unused,
699 pr_err("AUX area tracing not supported\n");
704 int auxtrace__process_event(struct perf_session *session __maybe_unused,
705 union perf_event *event __maybe_unused,
706 struct perf_sample *sample __maybe_unused,
707 struct perf_tool *tool __maybe_unused)
713 void auxtrace__dump_auxtrace_sample(struct perf_session *session __maybe_unused,
714 struct perf_sample *sample __maybe_unused)
719 int auxtrace__flush_events(struct perf_session *session __maybe_unused,
720 struct perf_tool *tool __maybe_unused)
726 void auxtrace__free_events(struct perf_session *session __maybe_unused)
731 void auxtrace_cache__free(struct auxtrace_cache *auxtrace_cache __maybe_unused)
736 void auxtrace__free(struct perf_session *session __maybe_unused)
741 int auxtrace_index__write(int fd __maybe_unused,
742 struct list_head *head __maybe_unused)
748 int auxtrace_index__process(int fd __maybe_unused,
749 u64 size __maybe_unused,
750 struct perf_session *session __maybe_unused,
751 bool needs_swap __maybe_unused)
757 void auxtrace_index__free(struct list_head *head __maybe_unused)
762 bool auxtrace__evsel_is_auxtrace(struct perf_session *session __maybe_unused,
763 struct evsel *evsel __maybe_unused)
769 int auxtrace_parse_filters(struct evlist *evlist __maybe_unused)
774 int auxtrace_mmap__mmap(struct auxtrace_mmap *mm,
775 struct auxtrace_mmap_params *mp,
776 void *userpg, int fd);
777 void auxtrace_mmap__munmap(struct auxtrace_mmap *mm);
778 void auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp,
779 off_t auxtrace_offset,
780 unsigned int auxtrace_pages,
781 bool auxtrace_overwrite);
782 void auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp,
783 struct evlist *evlist, int idx,
786 #define ITRACE_HELP ""
789 void itrace_synth_opts__set_time_range(struct itrace_synth_opts *opts
791 struct perf_time_interval *ptime_range
793 int range_num __maybe_unused)
798 void itrace_synth_opts__clear_time_range(struct itrace_synth_opts *opts