1 /*
2 * Copyright (C) 2018 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "src/traced/probes/ftrace/ftrace_config_muxer.h"
18
19 #include <string.h>
20 #include <sys/types.h>
21 #include <unistd.h>
22 #include <cstdint>
23
24 #include <algorithm>
25 #include <iterator>
26 #include <limits>
27
28 #include "perfetto/base/compiler.h"
29 #include "perfetto/ext/base/utils.h"
30 #include "protos/perfetto/trace/ftrace/generic.pbzero.h"
31 #include "src/traced/probes/ftrace/atrace_wrapper.h"
32 #include "src/traced/probes/ftrace/compact_sched.h"
33 #include "src/traced/probes/ftrace/ftrace_config_utils.h"
34 #include "src/traced/probes/ftrace/ftrace_stats.h"
35
36 #include "protos/perfetto/trace/ftrace/ftrace_event.pbzero.h"
37
38 namespace perfetto {
39 namespace {
40
41 using protos::pbzero::KprobeEvent;
42
43 constexpr uint64_t kDefaultLowRamPerCpuBufferSizeKb = 2 * (1ULL << 10); // 2mb
44 constexpr uint64_t kDefaultHighRamPerCpuBufferSizeKb = 8 * (1ULL << 10); // 8mb
45
46 // Threshold for physical ram size used when deciding on default kernel buffer
47 // sizes. We want to detect 8 GB, but the size reported through sysconf is
48 // usually lower.
49 constexpr uint64_t kHighMemBytes = 7 * (1ULL << 30); // 7gb
50
51 // A fake "syscall id" that indicates all syscalls should be recorded. This
52 // allows us to distinguish between the case where `syscall_events` is empty
53 // because raw_syscalls aren't enabled, or the case where it is and we want to
54 // record all events.
55 constexpr size_t kAllSyscallsId = kMaxSyscalls + 1;
56
57 // trace_clocks in preference order.
58 // If this list is changed, the FtraceClocks enum in ftrace_event_bundle.proto
59 // and FtraceConfigMuxer::SetupClock() should be also changed accordingly.
60 constexpr const char* kClocks[] = {"boot", "global", "local"};
61
62 // optional monotonic raw clock.
63 // Enabled by the "use_monotonic_raw_clock" option in the ftrace config.
64 constexpr const char* kClockMonoRaw = "mono_raw";
65
AddEventGroup(const ProtoTranslationTable * table,const std::string & group,std::set<GroupAndName> * to)66 void AddEventGroup(const ProtoTranslationTable* table,
67 const std::string& group,
68 std::set<GroupAndName>* to) {
69 const std::vector<const Event*>* events = table->GetEventsByGroup(group);
70 if (!events)
71 return;
72 for (const Event* event : *events)
73 to->insert(GroupAndName(group, event->name));
74 }
75
ReadEventsInGroupFromFs(const FtraceProcfs & ftrace_procfs,const std::string & group)76 std::set<GroupAndName> ReadEventsInGroupFromFs(
77 const FtraceProcfs& ftrace_procfs,
78 const std::string& group) {
79 std::set<std::string> names =
80 ftrace_procfs.GetEventNamesForGroup("events/" + group);
81 std::set<GroupAndName> events;
82 for (const auto& name : names)
83 events.insert(GroupAndName(group, name));
84 return events;
85 }
86
EventToStringGroupAndName(const std::string & event)87 std::pair<std::string, std::string> EventToStringGroupAndName(
88 const std::string& event) {
89 auto slash_pos = event.find('/');
90 if (slash_pos == std::string::npos)
91 return std::make_pair("", event);
92 return std::make_pair(event.substr(0, slash_pos),
93 event.substr(slash_pos + 1));
94 }
95
UnionInPlace(const std::vector<std::string> & unsorted_a,std::vector<std::string> * out)96 void UnionInPlace(const std::vector<std::string>& unsorted_a,
97 std::vector<std::string>* out) {
98 std::vector<std::string> a = unsorted_a;
99 std::sort(a.begin(), a.end());
100 std::sort(out->begin(), out->end());
101 std::vector<std::string> v;
102 std::set_union(a.begin(), a.end(), out->begin(), out->end(),
103 std::back_inserter(v));
104 *out = std::move(v);
105 }
106
IntersectInPlace(const std::vector<std::string> & unsorted_a,std::vector<std::string> * out)107 void IntersectInPlace(const std::vector<std::string>& unsorted_a,
108 std::vector<std::string>* out) {
109 std::vector<std::string> a = unsorted_a;
110 std::sort(a.begin(), a.end());
111 std::sort(out->begin(), out->end());
112 std::vector<std::string> v;
113 std::set_intersection(a.begin(), a.end(), out->begin(), out->end(),
114 std::back_inserter(v));
115 *out = std::move(v);
116 }
117
Subtract(const std::vector<std::string> & unsorted_a,const std::vector<std::string> & unsorted_b)118 std::vector<std::string> Subtract(const std::vector<std::string>& unsorted_a,
119 const std::vector<std::string>& unsorted_b) {
120 std::vector<std::string> a = unsorted_a;
121 std::sort(a.begin(), a.end());
122 std::vector<std::string> b = unsorted_b;
123 std::sort(b.begin(), b.end());
124 std::vector<std::string> v;
125 std::set_difference(a.begin(), a.end(), b.begin(), b.end(),
126 std::back_inserter(v));
127 return v;
128 }
129
130 // This is just to reduce binary size and stack frame size of the insertions.
131 // It effectively undoes STL's set::insert inlining.
InsertEvent(const char * group,const char * name,std::set<GroupAndName> * dst)132 void PERFETTO_NO_INLINE InsertEvent(const char* group,
133 const char* name,
134 std::set<GroupAndName>* dst) {
135 dst->insert(GroupAndName(group, name));
136 }
137
GetFtraceKprobeEvents(const FtraceConfig & request)138 std::map<GroupAndName, KprobeEvent::KprobeType> GetFtraceKprobeEvents(
139 const FtraceConfig& request) {
140 std::map<GroupAndName, KprobeEvent::KprobeType> events;
141 for (const auto& config_value : request.kprobe_events()) {
142 switch (config_value.type()) {
143 case protos::gen::FtraceConfig::KprobeEvent::KPROBE_TYPE_KPROBE:
144 events[GroupAndName(kKprobeGroup, config_value.probe().c_str())] =
145 KprobeEvent::KprobeType::KPROBE_TYPE_INSTANT;
146 break;
147 case protos::gen::FtraceConfig::KprobeEvent::KPROBE_TYPE_KRETPROBE:
148 events[GroupAndName(kKretprobeGroup, config_value.probe().c_str())] =
149 KprobeEvent::KprobeType::KPROBE_TYPE_INSTANT;
150 break;
151 case protos::gen::FtraceConfig::KprobeEvent::KPROBE_TYPE_BOTH:
152 events[GroupAndName(kKprobeGroup, config_value.probe().c_str())] =
153 KprobeEvent::KprobeType::KPROBE_TYPE_BEGIN;
154 events[GroupAndName(kKretprobeGroup, config_value.probe().c_str())] =
155 KprobeEvent::KprobeType::KPROBE_TYPE_END;
156 break;
157 case protos::gen::FtraceConfig::KprobeEvent::KPROBE_TYPE_UNKNOWN:
158 PERFETTO_DLOG("Unknown kprobe event");
159 break;
160 }
161 PERFETTO_DLOG("Added kprobe event: %s", config_value.probe().c_str());
162 }
163 return events;
164 }
165
ValidateKprobeName(const std::string & name)166 bool ValidateKprobeName(const std::string& name) {
167 for (const char& c : name) {
168 if (!std::isalnum(c) && c != '_') {
169 return false;
170 }
171 }
172 return true;
173 }
174
175 } // namespace
176
GetFtraceEvents(const FtraceConfig & request,const ProtoTranslationTable * table)177 std::set<GroupAndName> FtraceConfigMuxer::GetFtraceEvents(
178 const FtraceConfig& request,
179 const ProtoTranslationTable* table) {
180 std::set<GroupAndName> events;
181 for (const auto& config_value : request.ftrace_events()) {
182 std::string group;
183 std::string name;
184 std::tie(group, name) = EventToStringGroupAndName(config_value);
185 if (name == "*") {
186 for (const auto& event : ReadEventsInGroupFromFs(*ftrace_, group))
187 events.insert(event);
188 } else if (group.empty()) {
189 // If there is no group specified, find an event with that name and
190 // use it's group.
191 const Event* e = table->GetEventByName(name);
192 if (!e) {
193 PERFETTO_DLOG(
194 "Event doesn't exist: %s. Include the group in the config to allow "
195 "the event to be output as a generic event.",
196 name.c_str());
197 continue;
198 }
199 events.insert(GroupAndName(e->group, e->name));
200 } else {
201 events.insert(GroupAndName(group, name));
202 }
203 }
204 if (RequiresAtrace(request)) {
205 InsertEvent("ftrace", "print", &events);
206
207 // Ideally we should keep this code in sync with:
208 // platform/frameworks/native/cmds/atrace/atrace.cpp
209 // It's not a disaster if they go out of sync, we can always add the ftrace
210 // categories manually server side but this is user friendly and reduces the
211 // size of the configs.
212 for (const std::string& category : request.atrace_categories()) {
213 if (category == "gfx") {
214 AddEventGroup(table, "mdss", &events);
215 InsertEvent("mdss", "rotator_bw_ao_as_context", &events);
216 InsertEvent("mdss", "mdp_trace_counter", &events);
217 InsertEvent("mdss", "tracing_mark_write", &events);
218 InsertEvent("mdss", "mdp_cmd_wait_pingpong", &events);
219 InsertEvent("mdss", "mdp_cmd_kickoff", &events);
220 InsertEvent("mdss", "mdp_cmd_release_bw", &events);
221 InsertEvent("mdss", "mdp_cmd_readptr_done", &events);
222 InsertEvent("mdss", "mdp_cmd_pingpong_done", &events);
223 InsertEvent("mdss", "mdp_misr_crc", &events);
224 InsertEvent("mdss", "mdp_compare_bw", &events);
225 InsertEvent("mdss", "mdp_perf_update_bus", &events);
226 InsertEvent("mdss", "mdp_video_underrun_done", &events);
227 InsertEvent("mdss", "mdp_commit", &events);
228 InsertEvent("mdss", "mdp_mixer_update", &events);
229 InsertEvent("mdss", "mdp_perf_prefill_calc", &events);
230 InsertEvent("mdss", "mdp_perf_set_ot", &events);
231 InsertEvent("mdss", "mdp_perf_set_wm_levels", &events);
232 InsertEvent("mdss", "mdp_perf_set_panic_luts", &events);
233 InsertEvent("mdss", "mdp_perf_set_qos_luts", &events);
234 InsertEvent("mdss", "mdp_sspp_change", &events);
235 InsertEvent("mdss", "mdp_sspp_set", &events);
236 AddEventGroup(table, "mali", &events);
237 InsertEvent("mali", "tracing_mark_write", &events);
238
239 AddEventGroup(table, "sde", &events);
240 InsertEvent("sde", "tracing_mark_write", &events);
241 InsertEvent("sde", "sde_perf_update_bus", &events);
242 InsertEvent("sde", "sde_perf_set_qos_luts", &events);
243 InsertEvent("sde", "sde_perf_set_ot", &events);
244 InsertEvent("sde", "sde_perf_set_danger_luts", &events);
245 InsertEvent("sde", "sde_perf_crtc_update", &events);
246 InsertEvent("sde", "sde_perf_calc_crtc", &events);
247 InsertEvent("sde", "sde_evtlog", &events);
248 InsertEvent("sde", "sde_encoder_underrun", &events);
249 InsertEvent("sde", "sde_cmd_release_bw", &events);
250
251 AddEventGroup(table, "dpu", &events);
252 InsertEvent("dpu", "tracing_mark_write", &events);
253
254 AddEventGroup(table, "g2d", &events);
255 InsertEvent("g2d", "tracing_mark_write", &events);
256 InsertEvent("g2d", "g2d_perf_update_qos", &events);
257
258 AddEventGroup(table, "panel", &events);
259 InsertEvent("panel", "panel_write_generic", &events);
260 continue;
261 }
262
263 if (category == "ion") {
264 InsertEvent("kmem", "ion_alloc_buffer_start", &events);
265 continue;
266 }
267
268 // Note: sched_wakeup intentionally removed (diverging from atrace), as it
269 // is high-volume, but mostly redundant when sched_waking is also enabled.
270 // The event can still be enabled explicitly when necessary.
271 if (category == "sched") {
272 InsertEvent("sched", "sched_switch", &events);
273 InsertEvent("sched", "sched_waking", &events);
274 InsertEvent("sched", "sched_blocked_reason", &events);
275 InsertEvent("sched", "sched_cpu_hotplug", &events);
276 InsertEvent("sched", "sched_pi_setprio", &events);
277 InsertEvent("sched", "sched_process_exit", &events);
278 AddEventGroup(table, "cgroup", &events);
279 InsertEvent("cgroup", "cgroup_transfer_tasks", &events);
280 InsertEvent("cgroup", "cgroup_setup_root", &events);
281 InsertEvent("cgroup", "cgroup_rmdir", &events);
282 InsertEvent("cgroup", "cgroup_rename", &events);
283 InsertEvent("cgroup", "cgroup_remount", &events);
284 InsertEvent("cgroup", "cgroup_release", &events);
285 InsertEvent("cgroup", "cgroup_mkdir", &events);
286 InsertEvent("cgroup", "cgroup_destroy_root", &events);
287 InsertEvent("cgroup", "cgroup_attach_task", &events);
288 InsertEvent("oom", "oom_score_adj_update", &events);
289 InsertEvent("task", "task_rename", &events);
290 InsertEvent("task", "task_newtask", &events);
291
292 AddEventGroup(table, "systrace", &events);
293 InsertEvent("systrace", "0", &events);
294
295 AddEventGroup(table, "scm", &events);
296 InsertEvent("scm", "scm_call_start", &events);
297 InsertEvent("scm", "scm_call_end", &events);
298 continue;
299 }
300
301 if (category == "irq") {
302 AddEventGroup(table, "irq", &events);
303 InsertEvent("irq", "tasklet_hi_exit", &events);
304 InsertEvent("irq", "tasklet_hi_entry", &events);
305 InsertEvent("irq", "tasklet_exit", &events);
306 InsertEvent("irq", "tasklet_entry", &events);
307 InsertEvent("irq", "softirq_raise", &events);
308 InsertEvent("irq", "softirq_exit", &events);
309 InsertEvent("irq", "softirq_entry", &events);
310 InsertEvent("irq", "irq_handler_exit", &events);
311 InsertEvent("irq", "irq_handler_entry", &events);
312 AddEventGroup(table, "ipi", &events);
313 InsertEvent("ipi", "ipi_raise", &events);
314 InsertEvent("ipi", "ipi_exit", &events);
315 InsertEvent("ipi", "ipi_entry", &events);
316 continue;
317 }
318
319 if (category == "irqoff") {
320 InsertEvent("preemptirq", "irq_enable", &events);
321 InsertEvent("preemptirq", "irq_disable", &events);
322 continue;
323 }
324
325 if (category == "preemptoff") {
326 InsertEvent("preemptirq", "preempt_enable", &events);
327 InsertEvent("preemptirq", "preempt_disable", &events);
328 continue;
329 }
330
331 if (category == "i2c") {
332 AddEventGroup(table, "i2c", &events);
333 InsertEvent("i2c", "i2c_read", &events);
334 InsertEvent("i2c", "i2c_write", &events);
335 InsertEvent("i2c", "i2c_result", &events);
336 InsertEvent("i2c", "i2c_reply", &events);
337 InsertEvent("i2c", "smbus_read", &events);
338 InsertEvent("i2c", "smbus_write", &events);
339 InsertEvent("i2c", "smbus_result", &events);
340 InsertEvent("i2c", "smbus_reply", &events);
341 continue;
342 }
343
344 if (category == "freq") {
345 InsertEvent("power", "cpu_frequency", &events);
346 InsertEvent("power", "gpu_frequency", &events);
347 InsertEvent("power", "clock_set_rate", &events);
348 InsertEvent("power", "clock_disable", &events);
349 InsertEvent("power", "clock_enable", &events);
350 InsertEvent("clk", "clk_set_rate", &events);
351 InsertEvent("clk", "clk_disable", &events);
352 InsertEvent("clk", "clk_enable", &events);
353 InsertEvent("power", "cpu_frequency_limits", &events);
354 InsertEvent("power", "suspend_resume", &events);
355 InsertEvent("cpuhp", "cpuhp_enter", &events);
356 InsertEvent("cpuhp", "cpuhp_exit", &events);
357 InsertEvent("cpuhp", "cpuhp_pause", &events);
358 AddEventGroup(table, "msm_bus", &events);
359 InsertEvent("msm_bus", "bus_update_request_end", &events);
360 InsertEvent("msm_bus", "bus_update_request", &events);
361 InsertEvent("msm_bus", "bus_rules_matches", &events);
362 InsertEvent("msm_bus", "bus_max_votes", &events);
363 InsertEvent("msm_bus", "bus_client_status", &events);
364 InsertEvent("msm_bus", "bus_bke_params", &events);
365 InsertEvent("msm_bus", "bus_bimc_config_limiter", &events);
366 InsertEvent("msm_bus", "bus_avail_bw", &events);
367 InsertEvent("msm_bus", "bus_agg_bw", &events);
368 continue;
369 }
370
371 if (category == "membus") {
372 AddEventGroup(table, "memory_bus", &events);
373 continue;
374 }
375
376 if (category == "idle") {
377 InsertEvent("power", "cpu_idle", &events);
378 continue;
379 }
380
381 if (category == "disk") {
382 InsertEvent("f2fs", "f2fs_sync_file_enter", &events);
383 InsertEvent("f2fs", "f2fs_sync_file_exit", &events);
384 InsertEvent("f2fs", "f2fs_write_begin", &events);
385 InsertEvent("f2fs", "f2fs_write_end", &events);
386 InsertEvent("f2fs", "f2fs_iostat", &events);
387 InsertEvent("f2fs", "f2fs_iostat_latency", &events);
388 InsertEvent("ext4", "ext4_da_write_begin", &events);
389 InsertEvent("ext4", "ext4_da_write_end", &events);
390 InsertEvent("ext4", "ext4_sync_file_enter", &events);
391 InsertEvent("ext4", "ext4_sync_file_exit", &events);
392 InsertEvent("block", "block_bio_queue", &events);
393 InsertEvent("block", "block_bio_complete", &events);
394 InsertEvent("ufs", "ufshcd_command", &events);
395 continue;
396 }
397
398 if (category == "mmc") {
399 AddEventGroup(table, "mmc", &events);
400 continue;
401 }
402
403 if (category == "load") {
404 AddEventGroup(table, "cpufreq_interactive", &events);
405 continue;
406 }
407
408 if (category == "sync") {
409 // linux kernel < 4.9
410 AddEventGroup(table, "sync", &events);
411 InsertEvent("sync", "sync_pt", &events);
412 InsertEvent("sync", "sync_timeline", &events);
413 InsertEvent("sync", "sync_wait", &events);
414 // linux kernel == 4.9.x
415 AddEventGroup(table, "fence", &events);
416 InsertEvent("fence", "fence_annotate_wait_on", &events);
417 InsertEvent("fence", "fence_destroy", &events);
418 InsertEvent("fence", "fence_emit", &events);
419 InsertEvent("fence", "fence_enable_signal", &events);
420 InsertEvent("fence", "fence_init", &events);
421 InsertEvent("fence", "fence_signaled", &events);
422 InsertEvent("fence", "fence_wait_end", &events);
423 InsertEvent("fence", "fence_wait_start", &events);
424 // linux kernel > 4.9
425 AddEventGroup(table, "dma_fence", &events);
426 continue;
427 }
428
429 if (category == "workq") {
430 AddEventGroup(table, "workqueue", &events);
431 InsertEvent("workqueue", "workqueue_queue_work", &events);
432 InsertEvent("workqueue", "workqueue_execute_start", &events);
433 InsertEvent("workqueue", "workqueue_execute_end", &events);
434 InsertEvent("workqueue", "workqueue_activate_work", &events);
435 continue;
436 }
437
438 if (category == "memreclaim") {
439 InsertEvent("vmscan", "mm_vmscan_direct_reclaim_begin", &events);
440 InsertEvent("vmscan", "mm_vmscan_direct_reclaim_end", &events);
441 InsertEvent("vmscan", "mm_vmscan_kswapd_wake", &events);
442 InsertEvent("vmscan", "mm_vmscan_kswapd_sleep", &events);
443 AddEventGroup(table, "lowmemorykiller", &events);
444 InsertEvent("lowmemorykiller", "lowmemory_kill", &events);
445 continue;
446 }
447
448 if (category == "regulators") {
449 AddEventGroup(table, "regulator", &events);
450 events.insert(
451 GroupAndName("regulator", "regulator_set_voltage_complete"));
452 InsertEvent("regulator", "regulator_set_voltage", &events);
453 InsertEvent("regulator", "regulator_enable_delay", &events);
454 InsertEvent("regulator", "regulator_enable_complete", &events);
455 InsertEvent("regulator", "regulator_enable", &events);
456 InsertEvent("regulator", "regulator_disable_complete", &events);
457 InsertEvent("regulator", "regulator_disable", &events);
458 continue;
459 }
460
461 if (category == "binder_driver") {
462 InsertEvent("binder", "binder_transaction", &events);
463 InsertEvent("binder", "binder_transaction_received", &events);
464 InsertEvent("binder", "binder_transaction_alloc_buf", &events);
465 InsertEvent("binder", "binder_set_priority", &events);
466 continue;
467 }
468
469 if (category == "binder_lock") {
470 InsertEvent("binder", "binder_lock", &events);
471 InsertEvent("binder", "binder_locked", &events);
472 InsertEvent("binder", "binder_unlock", &events);
473 continue;
474 }
475
476 if (category == "pagecache") {
477 AddEventGroup(table, "filemap", &events);
478 events.insert(
479 GroupAndName("filemap", "mm_filemap_delete_from_page_cache"));
480 InsertEvent("filemap", "mm_filemap_add_to_page_cache", &events);
481 InsertEvent("filemap", "filemap_set_wb_err", &events);
482 InsertEvent("filemap", "file_check_and_advance_wb_err", &events);
483 continue;
484 }
485
486 if (category == "memory") {
487 // Use rss_stat_throttled if supported
488 if (ftrace_->SupportsRssStatThrottled()) {
489 InsertEvent("synthetic", "rss_stat_throttled", &events);
490 } else {
491 InsertEvent("kmem", "rss_stat", &events);
492 }
493 InsertEvent("kmem", "ion_heap_grow", &events);
494 InsertEvent("kmem", "ion_heap_shrink", &events);
495 // ion_stat supersedes ion_heap_grow / shrink for kernel 4.19+
496 InsertEvent("ion", "ion_stat", &events);
497 InsertEvent("mm_event", "mm_event_record", &events);
498 InsertEvent("dmabuf_heap", "dma_heap_stat", &events);
499 InsertEvent("gpu_mem", "gpu_mem_total", &events);
500 continue;
501 }
502
503 if (category == "thermal") {
504 InsertEvent("thermal", "thermal_temperature", &events);
505 InsertEvent("thermal", "cdev_update", &events);
506 continue;
507 }
508
509 if (category == "camera") {
510 AddEventGroup(table, "lwis", &events);
511 InsertEvent("lwis", "tracing_mark_write", &events);
512 continue;
513 }
514 }
515 }
516
517 // recording a subset of syscalls -> enable the backing events
518 if (request.syscall_events_size() > 0) {
519 InsertEvent("raw_syscalls", "sys_enter", &events);
520 InsertEvent("raw_syscalls", "sys_exit", &events);
521 }
522
523 // function_graph tracer emits two builtin ftrace events
524 if (request.enable_function_graph()) {
525 InsertEvent("ftrace", "funcgraph_entry", &events);
526 InsertEvent("ftrace", "funcgraph_exit", &events);
527 }
528
529 // If throttle_rss_stat: true, use the rss_stat_throttled event if supported
530 if (request.throttle_rss_stat() && ftrace_->SupportsRssStatThrottled()) {
531 auto it = std::find_if(
532 events.begin(), events.end(), [](const GroupAndName& event) {
533 return event.group() == "kmem" && event.name() == "rss_stat";
534 });
535
536 if (it != events.end()) {
537 events.erase(it);
538 InsertEvent("synthetic", "rss_stat_throttled", &events);
539 }
540 }
541
542 return events;
543 }
544
GetSyscallsReturningFds(const SyscallTable & syscalls)545 base::FlatSet<int64_t> FtraceConfigMuxer::GetSyscallsReturningFds(
546 const SyscallTable& syscalls) {
547 auto insertSyscallId = [&syscalls](base::FlatSet<int64_t>& set,
548 const char* syscall) {
549 auto syscall_id = syscalls.GetByName(syscall);
550 if (syscall_id)
551 set.insert(static_cast<int64_t>(*syscall_id));
552 };
553
554 base::FlatSet<int64_t> call_ids;
555 insertSyscallId(call_ids, "sys_open");
556 insertSyscallId(call_ids, "sys_openat");
557 insertSyscallId(call_ids, "sys_socket");
558 insertSyscallId(call_ids, "sys_dup");
559 insertSyscallId(call_ids, "sys_dup2");
560 insertSyscallId(call_ids, "sys_dup3");
561 return call_ids;
562 }
563
FilterHasGroup(const EventFilter & filter,const std::string & group)564 bool FtraceConfigMuxer::FilterHasGroup(const EventFilter& filter,
565 const std::string& group) {
566 const std::vector<const Event*>* events = table_->GetEventsByGroup(group);
567 if (!events) {
568 return false;
569 }
570
571 for (const Event* event : *events) {
572 if (filter.IsEventEnabled(event->ftrace_event_id)) {
573 return true;
574 }
575 }
576 return false;
577 }
578
BuildSyscallFilter(const EventFilter & ftrace_filter,const FtraceConfig & request)579 EventFilter FtraceConfigMuxer::BuildSyscallFilter(
580 const EventFilter& ftrace_filter,
581 const FtraceConfig& request) {
582 EventFilter output;
583
584 if (!FilterHasGroup(ftrace_filter, "raw_syscalls")) {
585 return output;
586 }
587
588 if (request.syscall_events().empty()) {
589 output.AddEnabledEvent(kAllSyscallsId);
590 return output;
591 }
592
593 for (const std::string& syscall : request.syscall_events()) {
594 std::optional<size_t> id = syscalls_.GetByName(syscall);
595 if (!id.has_value()) {
596 PERFETTO_ELOG("Can't enable %s, syscall not known", syscall.c_str());
597 continue;
598 }
599 output.AddEnabledEvent(*id);
600 }
601
602 return output;
603 }
604
SetSyscallEventFilter(const EventFilter & extra_syscalls)605 bool FtraceConfigMuxer::SetSyscallEventFilter(
606 const EventFilter& extra_syscalls) {
607 EventFilter syscall_filter;
608
609 syscall_filter.EnableEventsFrom(extra_syscalls);
610 for (const auto& id_config : ds_configs_) {
611 const perfetto::FtraceDataSourceConfig& config = id_config.second;
612 syscall_filter.EnableEventsFrom(config.syscall_filter);
613 }
614
615 std::set<size_t> filter_set = syscall_filter.GetEnabledEvents();
616 if (syscall_filter.IsEventEnabled(kAllSyscallsId)) {
617 filter_set.clear();
618 }
619
620 if (current_state_.syscall_filter != filter_set) {
621 if (!ftrace_->SetSyscallFilter(filter_set)) {
622 return false;
623 }
624
625 current_state_.syscall_filter = filter_set;
626 }
627
628 return true;
629 }
630
EnableFtraceEvent(const Event * event,const GroupAndName & group_and_name,EventFilter * filter,FtraceSetupErrors * errors)631 void FtraceConfigMuxer::EnableFtraceEvent(const Event* event,
632 const GroupAndName& group_and_name,
633 EventFilter* filter,
634 FtraceSetupErrors* errors) {
635 // Note: ftrace events are always implicitly enabled (and don't have an
636 // "enable" file). So they aren't tracked by the central event filter (but
637 // still need to be added to the per data source event filter to retain
638 // the events during parsing).
639 if (current_state_.ftrace_events.IsEventEnabled(event->ftrace_event_id) ||
640 std::string("ftrace") == event->group) {
641 filter->AddEnabledEvent(event->ftrace_event_id);
642 return;
643 }
644 if (ftrace_->EnableEvent(event->group, event->name)) {
645 current_state_.ftrace_events.AddEnabledEvent(event->ftrace_event_id);
646 filter->AddEnabledEvent(event->ftrace_event_id);
647 } else {
648 PERFETTO_DPLOG("Failed to enable %s.", group_and_name.ToString().c_str());
649 if (errors)
650 errors->failed_ftrace_events.push_back(group_and_name.ToString());
651 }
652 }
653
FtraceConfigMuxer(FtraceProcfs * ftrace,AtraceWrapper * atrace_wrapper,ProtoTranslationTable * table,SyscallTable syscalls,std::map<std::string,std::vector<GroupAndName>> vendor_events,bool secondary_instance)654 FtraceConfigMuxer::FtraceConfigMuxer(
655 FtraceProcfs* ftrace,
656 AtraceWrapper* atrace_wrapper,
657 ProtoTranslationTable* table,
658 SyscallTable syscalls,
659 std::map<std::string, std::vector<GroupAndName>> vendor_events,
660 bool secondary_instance)
661 : ftrace_(ftrace),
662 atrace_wrapper_(atrace_wrapper),
663 table_(table),
664 syscalls_(syscalls),
665 current_state_(),
666 vendor_events_(std::move(vendor_events)),
667 secondary_instance_(secondary_instance) {}
668 FtraceConfigMuxer::~FtraceConfigMuxer() = default;
669
SetupConfig(FtraceConfigId id,const FtraceConfig & request,FtraceSetupErrors * errors)670 bool FtraceConfigMuxer::SetupConfig(FtraceConfigId id,
671 const FtraceConfig& request,
672 FtraceSetupErrors* errors) {
673 EventFilter filter;
674 if (ds_configs_.empty()) {
675 PERFETTO_DCHECK(active_configs_.empty());
676
677 // If someone outside of perfetto is using a non-nop tracer, yield. We can't
678 // realistically figure out all notions of "in use" even if we look at
679 // set_event or events/enable, so this is all we check for.
680 if (!request.preserve_ftrace_buffer() && !ftrace_->IsTracingAvailable()) {
681 PERFETTO_ELOG(
682 "ftrace in use by non-Perfetto. Check that %s current_tracer is nop.",
683 ftrace_->GetRootPath().c_str());
684 return false;
685 }
686
687 // Clear tracefs state, remembering which value of "tracing_on" to restore
688 // to after we're done, though we won't restore the rest of the tracefs
689 // state.
690 current_state_.saved_tracing_on = ftrace_->GetTracingOn();
691 if (!request.preserve_ftrace_buffer()) {
692 ftrace_->SetTracingOn(false);
693 // This will fail on release ("user") builds due to ACLs, but that's
694 // acceptable since the per-event enabling/disabling should still be
695 // balanced.
696 ftrace_->DisableAllEvents();
697 ftrace_->ClearTrace();
698 }
699
700 // Set up the rest of the tracefs state, without starting it.
701 // Notes:
702 // * resizing buffers can be quite slow (up to hundreds of ms).
703 // * resizing buffers may truncate existing contents if the new size is
704 // smaller, which matters to the preserve_ftrace_buffer option.
705 if (!request.preserve_ftrace_buffer()) {
706 SetupClock(request);
707 SetupBufferSize(request);
708 }
709 }
710
711 std::set<GroupAndName> events = GetFtraceEvents(request, table_);
712 std::map<GroupAndName, KprobeEvent::KprobeType> events_kprobes =
713 GetFtraceKprobeEvents(request);
714
715 // Vendors can provide a set of extra ftrace categories to be enabled when a
716 // specific atrace category is used (e.g. "gfx" -> ["my_hw/my_custom_event",
717 // "my_hw/my_special_gpu"]). Merge them with the hard coded events for each
718 // categories.
719 for (const std::string& category : request.atrace_categories()) {
720 if (vendor_events_.count(category)) {
721 for (const GroupAndName& event : vendor_events_[category]) {
722 events.insert(event);
723 }
724 }
725 }
726
727 if (RequiresAtrace(request)) {
728 if (secondary_instance_) {
729 PERFETTO_ELOG(
730 "Secondary ftrace instances do not support atrace_categories and "
731 "atrace_apps options as they affect global state");
732 return false;
733 }
734 if (!atrace_wrapper_->SupportsUserspaceOnly() && !ds_configs_.empty()) {
735 PERFETTO_ELOG(
736 "Concurrent atrace sessions are not supported before Android P, "
737 "bailing out.");
738 return false;
739 }
740 UpdateAtrace(request, errors ? &errors->atrace_errors : nullptr);
741 }
742
743 base::FlatHashMap<uint32_t, KprobeEvent::KprobeType> kprobes;
744 for (const auto& [group_and_name, type] : events_kprobes) {
745 if (!ValidateKprobeName(group_and_name.name())) {
746 PERFETTO_ELOG("Invalid kprobes event %s", group_and_name.name().c_str());
747 if (errors)
748 errors->failed_ftrace_events.push_back(group_and_name.ToString());
749 continue;
750 }
751 // Kprobes events are created after their definition is written in the
752 // kprobe_events file
753 if (!ftrace_->CreateKprobeEvent(
754 group_and_name.group(), group_and_name.name(),
755 group_and_name.group() == kKretprobeGroup)) {
756 PERFETTO_ELOG("Failed creation of kprobes event %s",
757 group_and_name.name().c_str());
758 if (errors)
759 errors->failed_ftrace_events.push_back(group_and_name.ToString());
760 continue;
761 }
762
763 const Event* event = table_->GetOrCreateKprobeEvent(group_and_name);
764 if (!event) {
765 ftrace_->RemoveKprobeEvent(group_and_name.group(), group_and_name.name());
766
767 PERFETTO_ELOG("Can't enable kprobe %s",
768 group_and_name.ToString().c_str());
769 if (errors)
770 errors->unknown_ftrace_events.push_back(group_and_name.ToString());
771 continue;
772 }
773 current_state_.installed_kprobes.insert(group_and_name);
774 EnableFtraceEvent(event, group_and_name, &filter, errors);
775 kprobes[event->ftrace_event_id] = type;
776 }
777
778 for (const auto& group_and_name : events) {
779 if (group_and_name.group() == kKprobeGroup ||
780 group_and_name.group() == kKretprobeGroup) {
781 PERFETTO_DLOG("Can't enable %s, group reserved for kprobes",
782 group_and_name.ToString().c_str());
783 if (errors)
784 errors->failed_ftrace_events.push_back(group_and_name.ToString());
785 continue;
786 }
787 const Event* event = table_->GetOrCreateEvent(group_and_name);
788 if (!event) {
789 PERFETTO_DLOG("Can't enable %s, event not known",
790 group_and_name.ToString().c_str());
791 if (errors)
792 errors->unknown_ftrace_events.push_back(group_and_name.ToString());
793 continue;
794 }
795
796 // Niche option to skip events that are in the config, but don't have a
797 // dedicated proto for the event in perfetto. Otherwise such events will be
798 // encoded as GenericFtraceEvent.
799 if (request.disable_generic_events() &&
800 event->proto_field_id ==
801 protos::pbzero::FtraceEvent::kGenericFieldNumber) {
802 if (errors)
803 errors->failed_ftrace_events.push_back(group_and_name.ToString());
804 continue;
805 }
806
807 EnableFtraceEvent(event, group_and_name, &filter, errors);
808 }
809
810 EventFilter syscall_filter = BuildSyscallFilter(filter, request);
811 if (!SetSyscallEventFilter(syscall_filter)) {
812 PERFETTO_ELOG("Failed to set raw_syscall ftrace filter in SetupConfig");
813 return false;
814 }
815
816 // Kernel function tracing (function_graph).
817 // Note 1: there is no cleanup in |RemoveConfig| because tracers cannot be
818 // changed while tracing pipes are opened. So we'll keep the current_tracer
819 // until all data sources are gone, at which point ftrace_controller will
820 // make an explicit call to |ResetCurrentTracer|.
821 // Note 2: we don't track the set of filters ourselves and instead let the
822 // kernel statefully collate them, hence the use of |AppendFunctionFilters|.
823 // This is because each concurrent data source that wants funcgraph will get
824 // all of the enabled functions (we don't go as far as doing per-DS event
825 // steering in the parser), and we don't want to remove functions midway
826 // through a trace (but some might get added).
827 if (request.enable_function_graph()) {
828 if (!current_state_.funcgraph_on && !ftrace_->ClearFunctionFilters())
829 return false;
830 if (!current_state_.funcgraph_on && !ftrace_->ClearFunctionGraphFilters())
831 return false;
832 if (!ftrace_->AppendFunctionFilters(request.function_filters()))
833 return false;
834 if (!ftrace_->AppendFunctionGraphFilters(request.function_graph_roots()))
835 return false;
836 if (!current_state_.funcgraph_on &&
837 !ftrace_->SetCurrentTracer("function_graph")) {
838 PERFETTO_LOG(
839 "Unable to enable function_graph tracing since a concurrent ftrace "
840 "data source is using a different tracer");
841 return false;
842 }
843 current_state_.funcgraph_on = true;
844 }
845 const auto& compact_format = table_->compact_sched_format();
846 auto compact_sched = CreateCompactSchedConfig(
847 request, filter.IsEventEnabled(compact_format.sched_switch.event_id),
848 compact_format);
849 if (errors && !compact_format.format_valid) {
850 errors->failed_ftrace_events.emplace_back(
851 "perfetto/compact_sched (unexpected sched event format)");
852 }
853
854 std::optional<FtracePrintFilterConfig> ftrace_print_filter;
855 if (request.has_print_filter()) {
856 ftrace_print_filter =
857 FtracePrintFilterConfig::Create(request.print_filter(), table_);
858 if (!ftrace_print_filter.has_value()) {
859 if (errors) {
860 errors->failed_ftrace_events.emplace_back(
861 "ftrace/print (unexpected format for filtering)");
862 }
863 }
864 }
865
866 std::vector<std::string> apps(request.atrace_apps());
867 std::vector<std::string> categories(request.atrace_categories());
868 std::vector<std::string> categories_sdk_optout = Subtract(
869 request.atrace_categories(), request.atrace_categories_prefer_sdk());
870 auto [it, inserted] = ds_configs_.emplace(
871 std::piecewise_construct, std::forward_as_tuple(id),
872 std::forward_as_tuple(
873 std::move(filter), std::move(syscall_filter), compact_sched,
874 std::move(ftrace_print_filter), std::move(apps),
875 std::move(categories), std::move(categories_sdk_optout),
876 request.symbolize_ksyms(), request.drain_buffer_percent(),
877 GetSyscallsReturningFds(syscalls_)));
878 if (inserted) {
879 it->second.kprobes = std::move(kprobes);
880 }
881 return true;
882 }
883
ActivateConfig(FtraceConfigId id)884 bool FtraceConfigMuxer::ActivateConfig(FtraceConfigId id) {
885 if (!id || ds_configs_.count(id) == 0) {
886 PERFETTO_DFATAL("Config not found");
887 return false;
888 }
889
890 bool first_config = active_configs_.empty();
891 active_configs_.insert(id);
892
893 // Pick the lowest buffer_percent across the new set of active configs.
894 if (!UpdateBufferPercent()) {
895 PERFETTO_ELOG(
896 "Invalid FtraceConfig.drain_buffer_percent or "
897 "/sys/kernel/tracing/buffer_percent file permissions.");
898 // carry on, non-critical error
899 }
900
901 // Enable kernel event writer.
902 if (first_config) {
903 if (!ftrace_->SetTracingOn(true)) {
904 PERFETTO_ELOG("Failed to enable ftrace.");
905 active_configs_.erase(id);
906 return false;
907 }
908 }
909 return true;
910 }
911
RemoveConfig(FtraceConfigId config_id)912 bool FtraceConfigMuxer::RemoveConfig(FtraceConfigId config_id) {
913 if (!config_id || !ds_configs_.erase(config_id))
914 return false;
915 EventFilter expected_ftrace_events;
916 std::vector<std::string> expected_apps;
917 std::vector<std::string> expected_categories;
918 std::vector<std::string> expected_categories_sdk_optout;
919 for (const auto& id_config : ds_configs_) {
920 const perfetto::FtraceDataSourceConfig& config = id_config.second;
921 expected_ftrace_events.EnableEventsFrom(config.event_filter);
922 UnionInPlace(config.atrace_apps, &expected_apps);
923 UnionInPlace(config.atrace_categories, &expected_categories);
924 UnionInPlace(config.atrace_categories_sdk_optout,
925 &expected_categories_sdk_optout);
926 }
927 std::vector<std::string> expected_categories_prefer_sdk =
928 Subtract(expected_categories, expected_categories_sdk_optout);
929
930 // At this point expected_{apps,categories} contains the union of the
931 // leftover configs (if any) that should be still on. However we did not
932 // necessarily succeed in turning on atrace for each of those configs
933 // previously so we now intersect the {apps,categories} that we *did* manage
934 // to turn on with those we want on to determine the new state we should aim
935 // for:
936 IntersectInPlace(current_state_.atrace_apps, &expected_apps);
937 IntersectInPlace(current_state_.atrace_categories, &expected_categories);
938
939 // Work out if there is any difference between the current state and the
940 // desired state: It's sufficient to compare sizes here (since we know from
941 // above that expected_{apps,categories} is now a subset of
942 // atrace_{apps,categories}:
943 bool atrace_changed =
944 (current_state_.atrace_apps.size() != expected_apps.size()) ||
945 (current_state_.atrace_categories.size() != expected_categories.size());
946
947 bool atrace_prefer_sdk_changed =
948 current_state_.atrace_categories_prefer_sdk !=
949 expected_categories_prefer_sdk;
950
951 if (!SetSyscallEventFilter(/*extra_syscalls=*/{})) {
952 PERFETTO_ELOG("Failed to set raw_syscall ftrace filter in RemoveConfig");
953 }
954
955 // Disable any events that are currently enabled, but are not in any configs
956 // anymore.
957 std::set<size_t> event_ids = current_state_.ftrace_events.GetEnabledEvents();
958 for (size_t id : event_ids) {
959 if (expected_ftrace_events.IsEventEnabled(id))
960 continue;
961 const Event* event = table_->GetEventById(id);
962 // Any event that was enabled must exist.
963 PERFETTO_DCHECK(event);
964 if (ftrace_->DisableEvent(event->group, event->name))
965 current_state_.ftrace_events.DisableEvent(event->ftrace_event_id);
966 }
967
968 auto active_it = active_configs_.find(config_id);
969 if (active_it != active_configs_.end()) {
970 active_configs_.erase(active_it);
971 if (active_configs_.empty()) {
972 // This was the last active config for now, but potentially more dormant
973 // configs need to be activated. We are not interested in reading while no
974 // active configs so diasble tracing_on here.
975 ftrace_->SetTracingOn(false);
976 }
977 }
978
979 // Update buffer_percent to the minimum of the remaining configs.
980 UpdateBufferPercent();
981
982 // Even if we don't have any other active configs, we might still have idle
983 // configs around. Tear down the rest of the ftrace config only if all
984 // configs are removed.
985 if (ds_configs_.empty()) {
986 if (ftrace_->SetCpuBufferSizeInPages(1))
987 current_state_.cpu_buffer_size_pages = 1;
988 ftrace_->SetBufferPercent(50);
989 ftrace_->DisableAllEvents();
990 ftrace_->ClearTrace();
991 ftrace_->SetTracingOn(current_state_.saved_tracing_on);
992
993 // Kprobe cleanup cannot happen while we're still tracing as uninstalling
994 // kprobes clears all tracing buffers in the kernel.
995 for (const GroupAndName& probe : current_state_.installed_kprobes) {
996 ftrace_->RemoveKprobeEvent(probe.group(), probe.name());
997 table_->RemoveEvent(probe);
998 }
999 current_state_.installed_kprobes.clear();
1000 }
1001
1002 if (current_state_.atrace_on) {
1003 if (expected_apps.empty() && expected_categories.empty()) {
1004 DisableAtrace();
1005 } else if (atrace_changed) {
1006 // Update atrace to remove the no longer wanted categories/apps. For
1007 // some categories this won't disable them (e.g. categories that just
1008 // enable ftrace events) for those there is nothing we can do till the
1009 // last ftrace config is removed.
1010 if (StartAtrace(expected_apps, expected_categories,
1011 /*atrace_errors=*/nullptr)) {
1012 // Update current_state_ to reflect this change.
1013 current_state_.atrace_apps = expected_apps;
1014 current_state_.atrace_categories = expected_categories;
1015 }
1016 }
1017 }
1018
1019 if (atrace_prefer_sdk_changed) {
1020 if (SetAtracePreferSdk(expected_categories_prefer_sdk,
1021 /*atrace_errors=*/nullptr)) {
1022 current_state_.atrace_categories_prefer_sdk =
1023 expected_categories_prefer_sdk;
1024 }
1025 }
1026
1027 return true;
1028 }
1029
ResetCurrentTracer()1030 bool FtraceConfigMuxer::ResetCurrentTracer() {
1031 if (!current_state_.funcgraph_on)
1032 return true;
1033 if (!ftrace_->ResetCurrentTracer()) {
1034 PERFETTO_PLOG("Failed to reset current_tracer to nop");
1035 return false;
1036 }
1037 current_state_.funcgraph_on = false;
1038 if (!ftrace_->ClearFunctionFilters()) {
1039 PERFETTO_PLOG("Failed to reset set_ftrace_filter.");
1040 return false;
1041 }
1042 if (!ftrace_->ClearFunctionGraphFilters()) {
1043 PERFETTO_PLOG("Failed to reset set_function_graph.");
1044 return false;
1045 }
1046 return true;
1047 }
1048
GetDataSourceConfig(FtraceConfigId id)1049 const FtraceDataSourceConfig* FtraceConfigMuxer::GetDataSourceConfig(
1050 FtraceConfigId id) {
1051 if (!ds_configs_.count(id))
1052 return nullptr;
1053 return &ds_configs_.at(id);
1054 }
1055
SetupClock(const FtraceConfig & config)1056 void FtraceConfigMuxer::SetupClock(const FtraceConfig& config) {
1057 std::string current_clock = ftrace_->GetClock();
1058 std::set<std::string> clocks = ftrace_->AvailableClocks();
1059
1060 if (config.has_use_monotonic_raw_clock() &&
1061 config.use_monotonic_raw_clock() && clocks.count(kClockMonoRaw)) {
1062 ftrace_->SetClock(kClockMonoRaw);
1063 current_clock = kClockMonoRaw;
1064 } else {
1065 for (size_t i = 0; i < base::ArraySize(kClocks); i++) {
1066 std::string clock = std::string(kClocks[i]);
1067 if (!clocks.count(clock))
1068 continue;
1069 if (current_clock == clock)
1070 break;
1071 ftrace_->SetClock(clock);
1072 current_clock = clock;
1073 break;
1074 }
1075 }
1076
1077 namespace pb0 = protos::pbzero;
1078 if (current_clock == "boot") {
1079 // "boot" is the default expectation on modern kernels, which is why we
1080 // don't have an explicit FTRACE_CLOCK_BOOT enum and leave it unset.
1081 // See comments in ftrace_event_bundle.proto.
1082 current_state_.ftrace_clock = pb0::FTRACE_CLOCK_UNSPECIFIED;
1083 } else if (current_clock == "global") {
1084 current_state_.ftrace_clock = pb0::FTRACE_CLOCK_GLOBAL;
1085 } else if (current_clock == "local") {
1086 current_state_.ftrace_clock = pb0::FTRACE_CLOCK_LOCAL;
1087 } else if (current_clock == kClockMonoRaw) {
1088 current_state_.ftrace_clock = pb0::FTRACE_CLOCK_MONO_RAW;
1089 } else {
1090 current_state_.ftrace_clock = pb0::FTRACE_CLOCK_UNKNOWN;
1091 }
1092 }
1093
SetupBufferSize(const FtraceConfig & request)1094 void FtraceConfigMuxer::SetupBufferSize(const FtraceConfig& request) {
1095 int64_t phys_ram_pages = sysconf(_SC_PHYS_PAGES);
1096 size_t pages = ComputeCpuBufferSizeInPages(request.buffer_size_kb(),
1097 request.buffer_size_lower_bound(),
1098 phys_ram_pages);
1099 ftrace_->SetCpuBufferSizeInPages(pages);
1100 current_state_.cpu_buffer_size_pages = pages;
1101 }
1102
1103 // Post-conditions:
1104 // * result >= 1 (should have at least one page per CPU)
1105 // * If input is 0 output is a good default number
ComputeCpuBufferSizeInPages(size_t requested_buffer_size_kb,bool buffer_size_lower_bound,int64_t sysconf_phys_pages)1106 size_t ComputeCpuBufferSizeInPages(size_t requested_buffer_size_kb,
1107 bool buffer_size_lower_bound,
1108 int64_t sysconf_phys_pages) {
1109 uint32_t page_sz = base::GetSysPageSize();
1110 uint64_t default_size_kb =
1111 (sysconf_phys_pages > 0 &&
1112 (static_cast<uint64_t>(sysconf_phys_pages) >= (kHighMemBytes / page_sz)))
1113 ? kDefaultHighRamPerCpuBufferSizeKb
1114 : kDefaultLowRamPerCpuBufferSizeKb;
1115
1116 size_t actual_size_kb = requested_buffer_size_kb;
1117 if ((requested_buffer_size_kb == 0) ||
1118 (buffer_size_lower_bound && default_size_kb > requested_buffer_size_kb)) {
1119 actual_size_kb = default_size_kb;
1120 }
1121
1122 size_t pages = actual_size_kb / (page_sz / 1024);
1123 return pages ? pages : 1;
1124 }
1125
1126 // TODO(rsavitski): stop caching the "input" value, as the kernel can and will
1127 // choose a slightly different buffer size (especially on 6.x kernels). And even
1128 // then the value might not be exactly page accurate due to scratch pages (more
1129 // of a concern for the |FtraceController::FlushForInstance| caller).
GetPerCpuBufferSizePages()1130 size_t FtraceConfigMuxer::GetPerCpuBufferSizePages() {
1131 return current_state_.cpu_buffer_size_pages;
1132 }
1133
1134 // If new_cfg_id is set, consider it in addition to already active configs
1135 // as we're trying to activate it.
UpdateBufferPercent()1136 bool FtraceConfigMuxer::UpdateBufferPercent() {
1137 uint32_t kUnsetPercent = std::numeric_limits<uint32_t>::max();
1138 uint32_t min_percent = kUnsetPercent;
1139 for (auto cfg_id : active_configs_) {
1140 auto ds_it = ds_configs_.find(cfg_id);
1141 if (ds_it != ds_configs_.end() && ds_it->second.buffer_percent > 0) {
1142 min_percent = std::min(min_percent, ds_it->second.buffer_percent);
1143 }
1144 }
1145 if (min_percent == kUnsetPercent)
1146 return true;
1147 // Let the kernel ignore values >100.
1148 return ftrace_->SetBufferPercent(min_percent);
1149 }
1150
UpdateAtrace(const FtraceConfig & request,std::string * atrace_errors)1151 void FtraceConfigMuxer::UpdateAtrace(const FtraceConfig& request,
1152 std::string* atrace_errors) {
1153 // We want to avoid poisoning current_state_.atrace_{categories, apps}
1154 // if for some reason these args make atrace unhappy so we stash the
1155 // union into temps and only update current_state_ if we successfully
1156 // run atrace.
1157
1158 std::vector<std::string> combined_categories = request.atrace_categories();
1159 UnionInPlace(current_state_.atrace_categories, &combined_categories);
1160
1161 std::vector<std::string> combined_apps = request.atrace_apps();
1162 UnionInPlace(current_state_.atrace_apps, &combined_apps);
1163
1164 // Each data source can list some atrace categories for which the SDK is
1165 // preferred (the rest of the categories are considered to opt out of the
1166 // SDK). When merging multiple data sources, opting out wins. Therefore this
1167 // code does a union of the opt outs for all data sources.
1168 std::vector<std::string> combined_categories_sdk_optout = Subtract(
1169 request.atrace_categories(), request.atrace_categories_prefer_sdk());
1170
1171 std::vector<std::string> current_categories_sdk_optout =
1172 Subtract(current_state_.atrace_categories,
1173 current_state_.atrace_categories_prefer_sdk);
1174 UnionInPlace(current_categories_sdk_optout, &combined_categories_sdk_optout);
1175
1176 std::vector<std::string> combined_categories_prefer_sdk =
1177 Subtract(combined_categories, combined_categories_sdk_optout);
1178
1179 if (combined_categories_prefer_sdk !=
1180 current_state_.atrace_categories_prefer_sdk) {
1181 if (SetAtracePreferSdk(combined_categories_prefer_sdk, atrace_errors)) {
1182 current_state_.atrace_categories_prefer_sdk =
1183 combined_categories_prefer_sdk;
1184 }
1185 }
1186
1187 if (!current_state_.atrace_on ||
1188 combined_apps.size() != current_state_.atrace_apps.size() ||
1189 combined_categories.size() != current_state_.atrace_categories.size()) {
1190 if (StartAtrace(combined_apps, combined_categories, atrace_errors)) {
1191 current_state_.atrace_categories = combined_categories;
1192 current_state_.atrace_apps = combined_apps;
1193 current_state_.atrace_on = true;
1194 }
1195 }
1196 }
1197
StartAtrace(const std::vector<std::string> & apps,const std::vector<std::string> & categories,std::string * atrace_errors)1198 bool FtraceConfigMuxer::StartAtrace(const std::vector<std::string>& apps,
1199 const std::vector<std::string>& categories,
1200 std::string* atrace_errors) {
1201 PERFETTO_DLOG("Update atrace config...");
1202
1203 std::vector<std::string> args;
1204 args.push_back("atrace"); // argv0 for exec()
1205 args.push_back("--async_start");
1206 if (atrace_wrapper_->SupportsUserspaceOnly())
1207 args.push_back("--only_userspace");
1208
1209 for (const auto& category : categories)
1210 args.push_back(category);
1211
1212 if (!apps.empty()) {
1213 args.push_back("-a");
1214 std::string arg = "";
1215 for (const auto& app : apps) {
1216 arg += app;
1217 arg += ",";
1218 }
1219 arg.resize(arg.size() - 1);
1220 args.push_back(arg);
1221 }
1222
1223 bool result = atrace_wrapper_->RunAtrace(args, atrace_errors);
1224 PERFETTO_DLOG("...done (%s)", result ? "success" : "fail");
1225 return result;
1226 }
1227
SetAtracePreferSdk(const std::vector<std::string> & prefer_sdk_categories,std::string * atrace_errors)1228 bool FtraceConfigMuxer::SetAtracePreferSdk(
1229 const std::vector<std::string>& prefer_sdk_categories,
1230 std::string* atrace_errors) {
1231 if (!atrace_wrapper_->SupportsPreferSdk()) {
1232 return false;
1233 }
1234 PERFETTO_DLOG("Update atrace prefer sdk categories...");
1235
1236 std::vector<std::string> args;
1237 args.push_back("atrace"); // argv0 for exec()
1238 args.push_back("--prefer_sdk");
1239
1240 for (const auto& category : prefer_sdk_categories)
1241 args.push_back(category);
1242
1243 bool result = atrace_wrapper_->RunAtrace(args, atrace_errors);
1244 PERFETTO_DLOG("...done (%s)", result ? "success" : "fail");
1245 return result;
1246 }
1247
DisableAtrace()1248 void FtraceConfigMuxer::DisableAtrace() {
1249 PERFETTO_DCHECK(current_state_.atrace_on);
1250
1251 PERFETTO_DLOG("Stop atrace...");
1252
1253 std::vector<std::string> args{"atrace", "--async_stop"};
1254 if (atrace_wrapper_->SupportsUserspaceOnly())
1255 args.push_back("--only_userspace");
1256 if (atrace_wrapper_->RunAtrace(args, /*atrace_errors=*/nullptr)) {
1257 current_state_.atrace_categories.clear();
1258 current_state_.atrace_apps.clear();
1259 current_state_.atrace_on = false;
1260 }
1261
1262 PERFETTO_DLOG("...done");
1263 }
1264
1265 } // namespace perfetto
1266