/* * Copyright (C) 2017 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ syntax = "proto2"; package perfetto.protos; import "protos/perfetto/common/builtin_clock.proto"; import "protos/perfetto/config/data_source_config.proto"; // The overall config that is used when starting a new tracing session through // ProducerPort::StartTracing(). // It contains the general config for the logging buffer(s) and the configs for // all the data source being enabled. // // Next id: 40. message TraceConfig { message BufferConfig { optional uint32 size_kb = 1; // |page_size|, now deprecated. reserved 2; // |optimize_for|, now deprecated. reserved 3; enum FillPolicy { UNSPECIFIED = 0; // Default behavior. The buffer operates as a conventional ring buffer. // If the writer is faster than the reader (or if the reader reads only // after tracing is stopped) newly written packets will overwrite old // packets. RING_BUFFER = 1; // Behaves like RING_BUFFER as long as there is space in the buffer or // the reader catches up with the writer. As soon as the writer hits // an unread chunk, it stops accepting new data in the buffer. DISCARD = 2; } optional FillPolicy fill_policy = 4; // When true the buffer is moved (rather than copied) onto the cloned // session, and an empty buffer of the same size is allocated in the source // tracing session. This feature will likely get deprecated in the future. // It been introduced mainly to support the surfaceflinger snapshot dump // for bugreports, where SF can dumps O(400MB) into the bugreport trace. In // that case we don't want to retain another in-memory copy of the buffer. optional bool transfer_on_clone = 5; // Used in conjuction with transfer_on_clone. When true the buffer is // cleared before issuing the Flush(reason=kTraceClone). This is to ensure // that if the data source took too long to write the data in a previous // clone-related flush, we don't end up with a mixture of leftovers from // the previous write and new data. optional bool clear_before_clone = 6; } repeated BufferConfig buffers = 1; message DataSource { // Filters and data-source specific config. It contains also the unique name // of the data source, the one passed in the DataSourceDescriptor when they // register on the service. optional protos.DataSourceConfig config = 1; // Optional. If multiple producers (~processes) expose the same data source // and either |producer_name_filter| or |producer_name_regex_filter| is set, // the data source is enabled only for producers whose names match any of // the filters. // |producer_name_filter| has to be an exact match, while // |producer_name_regex_filter| is a regular expression. // This allows to enable a data source only for specific processes. // The "repeated" fields have OR semantics: specifying a filter ["foo", // "bar"] will enable data sources on both "foo" and "bar" (if they exist). repeated string producer_name_filter = 2; repeated string producer_name_regex_filter = 3; } repeated DataSource data_sources = 2; // Config for disabling builtin data sources in the tracing service. message BuiltinDataSource { // Disable emitting clock timestamps into the trace. optional bool disable_clock_snapshotting = 1; // Disable echoing the original trace config in the trace. optional bool disable_trace_config = 2; // Disable emitting system info (build fingerprint, cpuinfo, etc). optional bool disable_system_info = 3; // Disable emitting events for data-source state changes (e.g. the marker // for all data sources having ACKed the start of the trace). optional bool disable_service_events = 4; // The authoritative clock domain for the trace. Defaults to BOOTTIME. See // also ClockSnapshot's primary_trace_clock. The configured value is written // into the trace as part of the ClockSnapshots emitted by the service. // Trace processor will attempt to translate packet/event timestamps from // various data sources (and their chosen clock domains) to this domain // during import. Added in Android R. optional BuiltinClock primary_trace_clock = 5; // Time interval in between snapshotting of sync markers, clock snapshots, // stats, and other periodic service-emitted events. Note that the service // only keeps track of the first and the most recent snapshot until // ReadBuffers() is called. optional uint32 snapshot_interval_ms = 6; // Hints to the service that a suspend-aware (i.e. counting time in suspend) // clock should be used for periodic snapshots of service-emitted events. // This means, if a snapshot *should* have happened during suspend, it will // happen immediately after the device resumes. // // Choosing a clock like this is done on best-effort basis; not all // platforms (e.g. Windows) expose a clock which can be used for periodic // tasks counting suspend. If such a clock is not available, the service // falls back to the best-available alternative. // // Introduced in Android S. // TODO(lalitm): deprecate this in T and make this the default if nothing // crashes in S. optional bool prefer_suspend_clock_for_snapshot = 7; // Disables the reporting of per-trace-writer histograms in TraceStats. optional bool disable_chunk_usage_histograms = 8; } optional BuiltinDataSource builtin_data_sources = 20; // If specified, the trace will be stopped |duration_ms| after starting. // This does *not* count the time the system is suspended, so we will run // for duration_ms of system activity, not wall time. // // However in case of traces with triggers, see // TriggerConfig.trigger_timeout_ms instead. optional uint32 duration_ms = 3; // If true, tries to use CLOCK_BOOTTIME for duration_ms rather than // CLOCK_MONOTONIC (which doesn't count time in suspend). Supported only on // Linux/Android, no-op on other platforms. This is used when dealing with // long (e.g. 24h) traces, where suspend can inflate them to weeks of // wall-time, making them more likely to hit device reboots (and hence loss). // This option also changes consistently the semantic of // TriggerConfig.stop_delay_ms. optional bool prefer_suspend_clock_for_duration = 36; // This is set when --dropbox is passed to the Perfetto command line client // and enables guardrails that limit resource usage for traces requested // by statsd. optional bool enable_extra_guardrails = 4; enum LockdownModeOperation { LOCKDOWN_UNCHANGED = 0; LOCKDOWN_CLEAR = 1; LOCKDOWN_SET = 2; } // Reject producers that are not running under the same UID as the tracing // service. optional LockdownModeOperation lockdown_mode = 5; message ProducerConfig { // Identifies the producer for which this config is for. optional string producer_name = 1; // Specifies the preferred size of the shared memory buffer. If the size is // larger than the max size, the max will be used. If it is smaller than // the page size or doesn't fit pages evenly into it, it will fall back to // the size specified by the producer or finally the default shared memory // size. optional uint32 shm_size_kb = 2; // Specifies the preferred size of each page in the shared memory buffer. // Must be an integer multiple of 4K. optional uint32 page_size_kb = 3; } repeated ProducerConfig producers = 6; // Contains statsd-specific metadata about an alert associated with the trace. message StatsdMetadata { // The identifier of the alert which triggered this trace. optional int64 triggering_alert_id = 1; // The uid which registered the triggering configuration with statsd. optional int32 triggering_config_uid = 2; // The identifier of the config which triggered the alert. optional int64 triggering_config_id = 3; // The identifier of the subscription which triggered this trace. optional int64 triggering_subscription_id = 4; } // Statsd-specific metadata. optional StatsdMetadata statsd_metadata = 7; // When true && |output_path| is empty, the EnableTracing() request must // provide a file descriptor. The service will then periodically read packets // out of the trace buffer and store it into the passed file. // If |output_path| is not empty no fd should be passed, the service // will create a new file and write into that (see comment below). optional bool write_into_file = 8; // This must point to a non-existing file. If the file exists the service // will NOT overwrite and will fail instead as a security precaution. // On Android, when this is used with the system traced, the path must be // within /data/misc/perfetto-traces/ or the trace will fail. // This option has been introduced in Android R. Before R write_into_file // can be used only with the "pass a file descriptor over IPC" mode. optional string output_path = 29; // Optional. If non-zero tunes the write period. A min value of 100ms is // enforced (i.e. smaller values are ignored). optional uint32 file_write_period_ms = 9; // Optional. When non zero the periodic write stops once at most X bytes // have been written into the file. Tracing is disabled when this limit is // reached, even if |duration_ms| has not been reached yet. optional uint64 max_file_size_bytes = 10; // Contains flags which override the default values of the guardrails inside // Perfetto. message GuardrailOverrides { // Override the default limit (in bytes) for uploading data to server within // a 24 hour period. // On R-, this override only affected userdebug builds. Since S, it also // affects user builds. // In 24Q3+ (V+), this override is a noop because upload guardrail logic // was removed from Perfetto. optional uint64 max_upload_per_day_bytes = 1 [deprecated = true]; // Overrides the guardrail for maximum trace buffer size. // Available on U+ optional uint32 max_tracing_buffer_size_kb = 2; } optional GuardrailOverrides guardrail_overrides = 11; // When true, data sources are not started until an explicit call to // StartTracing() on the consumer port. This is to support early // initialization and fast trace triggering. This can be used only when the // Consumer explicitly triggers the StartTracing() method. // This should not be used in a remote trace config via statsd, doing so will // result in a hung trace session. optional bool deferred_start = 12; // When set, it periodically issues a Flush() to all data source, forcing them // to commit their data into the tracing service. This can be used for // quasi-real-time streaming mode and to guarantee some partial ordering of // events in the trace in windows of X ms. optional uint32 flush_period_ms = 13; // Wait for this long for producers to acknowledge flush requests. // Default 5s. optional uint32 flush_timeout_ms = 14; // Wait for this long for producers to acknowledge stop requests. // Default 5s. optional uint32 data_source_stop_timeout_ms = 23; // |disable_clock_snapshotting| moved. reserved 15; // Android-only. If set, sends an intent to the Traceur system app when the // trace ends to notify it about the trace readiness. optional bool notify_traceur = 16; // This field was introduced in Android S. // Android-only. If set to a value > 0, marks the trace session as a candidate // for being attached to a bugreport. This field effectively acts as a z-index // for bugreports. When Android's dumpstate runs perfetto // --save-for-bugreport, traced will pick the tracing session with the highest // score (score <= 0 is ignored) and: // On Android S, T: will steal its contents, save the trace into // a known path and stop prematurely. // On Android U+: will create a read-only snapshot and save that into a known // path, without stoppin the original tracing session. // When this field is set the tracing session becomes eligible to be cloned // by other UIDs. optional int32 bugreport_score = 30; // When set, defines name of the file that will be saved under // /data/misc/perfetto-traces/bugreport/ when using --save-all-for-bugreport. // If omitted, traces will be named systrace.pftrace, systrace_1.pftrace, etc, // starting from the highest `bugreport_score`. // Introduced in v42 / Android V. optional string bugreport_filename = 38; // Triggers allow producers to start or stop the tracing session when an event // occurs. // // For example if we are tracing probabilistically, most traces will be // uninteresting. Triggers allow us to keep only the interesting ones such as // those traces during which the device temperature reached a certain // threshold. In this case the producer can activate a trigger to keep // (STOP_TRACING) the trace, otherwise it can also begin a trace // (START_TRACING) because it knows something is about to happen. message TriggerConfig { enum TriggerMode { UNSPECIFIED = 0; // When this mode is chosen, data sources are not started until one of the // |triggers| are received. This supports early initialization and fast // starting of the tracing system. On triggering, the session will then // record for |stop_delay_ms|. However if no trigger is seen // after |trigger_timeout_ms| the session will be stopped and no data will // be returned. START_TRACING = 1; // When this mode is chosen, the session will be started via the normal // EnableTracing() & StartTracing(). If no trigger is ever seen // the session will be stopped after |trigger_timeout_ms| and no data will // be returned. However if triggered the trace will stop after // |stop_delay_ms| and any data in the buffer will be returned to the // consumer. STOP_TRACING = 2; // 3 was taken by CLONE_SNAPSHOT but that has been moved to 4. // The early implementation of CLONE_SNAPSHOT had various bugs // (b/290798988, b/290799105) and made it into Android U. The number // change is to make sure nobody rolls out a config that hits the broken // behaviour. reserved 3; // When this mode is chosen, this causes a snapshot of the current tracing // session to be created after |stop_delay_ms| while the current tracing // session continues undisturbed (% an extra flush). This mode can be // used only when the tracing session is handled by the "perfetto" cmdline // client (which is true in 90% of cases). Part of the business logic // necessary for this behavior, and ensuing file handling, lives in // perfetto_cmd.cc . On other consumers, this causes only a notification // of the trigger through a CloneTriggerHit ObservableEvent. The custom // consumer is supposed to call CloneSession() itself after the event. // Use use_clone_snapshot_if_available=true when targeting older versions // of perfetto. CLONE_SNAPSHOT = 4; // NOTE: CLONE_SNAPSHOT should be used only when we targeting Android V+ // (15+) / Perfetto v38+. A bug in older versions of the tracing service // might cause indefinitely long tracing sessions (see b/274931668). } optional TriggerMode trigger_mode = 1; // This flag is really a workaround for b/274931668. This is needed only // when deploying configs to different versions of the tracing service. // When this is set to true this has the same effect of setting trigger_mode // to CLONE_SNAPSHOT on newer versions of the service. This boolean has been // introduced to allow to have configs that use CLONE_SNAPSHOT on newer // versions of Android and fall back to STOP_TRACING on older versions where // CLONE_SNAPSHOT did not exist. // When using this flag, trigger_mode must be set to STOP_TRACING. optional bool use_clone_snapshot_if_available = 5; // DEPRECATED, was use_clone_snapshot_if_available in U. See the comment // around CLONE_SNAPSHOT. reserved 4; message Trigger { // The producer must specify this name to activate the trigger. optional string name = 1; // An std::regex that will match the producer that can activate this // trigger. This is optional. If unset any producers can activate this // trigger. optional string producer_name_regex = 2; // After a trigger is received either in START_TRACING or STOP_TRACING // mode then the trace will end |stop_delay_ms| after triggering. // In CLONE_SNAPSHOT mode, this is the delay between the trigger and the // snapshot. // If |prefer_suspend_clock_for_duration| is set, the duration will be // based on wall-clock, counting also time in suspend. optional uint32 stop_delay_ms = 3; // Limits the number of traces this trigger can start/stop in a rolling // 24 hour window. If this field is unset or zero, no limit is applied and // activiation of this trigger *always* starts/stops the trace. optional uint32 max_per_24_h = 4; // A value between 0 and 1 which encodes the probability of skipping a // trigger with this name. This is useful for reducing the probability // of high-frequency triggers from dominating trace finaization. If this // field is unset or zero, the trigger will *never* be skipped. If this // field is greater than or equal to 1, this trigger will *always* be // skipped i.e. it will be as if this trigger was never included in the // first place. // This probability check is applied *before* any other limits. For // example, if |max_per_24_h| is also set, first we will check if the // probability bar is met and only then will we check the |max_per_24_h| // limit. optional double skip_probability = 5; } // A list of triggers which are related to this configuration. If ANY // trigger is seen then an action will be performed based on |trigger_mode|. repeated Trigger triggers = 2; // Required and must be positive if a TriggerConfig is specified. This is // how long this TraceConfig should wait for a trigger to arrive. After this // period of time if no trigger is seen the TracingSession will be cleaned // up. optional uint32 trigger_timeout_ms = 3; } optional TriggerConfig trigger_config = 17; // When this is non-empty the perfetto command line tool will ignore the rest // of this TraceConfig and instead connect to the perfetto service as a // producer and send these triggers, potentially stopping or starting traces // that were previous configured to use a TriggerConfig. repeated string activate_triggers = 18; // Configuration for trace contents that reference earlier trace data. For // example, a data source might intern strings, and emit packets containing // {interned id : string} pairs. Future packets from that data source can then // use the interned ids instead of duplicating the raw string contents. The // trace parser will then need to use that interning table to fully interpret // the rest of the trace. message IncrementalStateConfig { // If nonzero, notify eligible data sources to clear their incremental state // periodically, with the given period. The notification is sent only to // data sources that have |handles_incremental_state_clear| set in their // DataSourceDescriptor. The notification requests that the data source // stops referring to past trace contents. This is particularly useful when // tracing in ring buffer mode, where it is not exceptional to overwrite old // trace data. // // Warning: this time-based global clearing is likely to be removed in the // future, to be replaced with a smarter way of sending the notifications // only when necessary. optional uint32 clear_period_ms = 1; } optional IncrementalStateConfig incremental_state_config = 21; // Additional guardrail used by the Perfetto command line client. // On user builds when --dropbox is set perfetto will refuse to trace unless // this is also set. // Added in Q. optional bool allow_user_build_tracing = 19; // If set the tracing service will ensure there is at most one tracing session // with this key. optional string unique_session_name = 22; // Compress trace with the given method. Best effort. enum CompressionType { COMPRESSION_TYPE_UNSPECIFIED = 0; COMPRESSION_TYPE_DEFLATE = 1; } optional CompressionType compression_type = 24; // DEPRECATED, was compress_from_cli. reserved 37; // Android-only. Not for general use. If set, saves the trace into an // incident. This field is read by perfetto_cmd, rather than the tracing // service. This field must be set when passing the --upload flag to // perfetto_cmd. message IncidentReportConfig { // In this message, either: // * all of |destination_package|, |destination_class| and |privacy_level| // must be set. // * |skip_incidentd| must be explicitly set to true. optional string destination_package = 1; optional string destination_class = 2; // Level of filtering in the requested incident. See |Destination| in // frameworks/base/core/proto/android/privacy.proto. optional int32 privacy_level = 3; // If true, then skips saving the trace to incidentd. // // This flag is useful in testing (e.g. Perfetto-statsd integration tests) // or when we explicitly don't want traces to go to incidentd even when they // usually would (e.g. configs deployed using statsd but only used for // inclusion in bugreports using |bugreport_score|). // // The motivation for having this flag, instead of just not setting // |incident_report_config|, is prevent accidents where // |incident_report_config| is omitted by mistake. optional bool skip_incidentd = 5; // If true, do not write the trace into dropbox (i.e. incident only). // Otherwise, write to both dropbox and incident. // TODO(lalitm): remove this field as we no longer use Dropbox. optional bool skip_dropbox = 4 [deprecated = true]; } optional IncidentReportConfig incident_report_config = 25; enum StatsdLogging { STATSD_LOGGING_UNSPECIFIED = 0; STATSD_LOGGING_ENABLED = 1; STATSD_LOGGING_DISABLED = 2; } // Android-only. Not for general use. If specified, sets the logging to statsd // of guardrails and checkpoints in the tracing service. perfetto_cmd sets // this to enabled (if not explicitly set in the config) when specifying // --upload. optional StatsdLogging statsd_logging = 31; // DEPRECATED. Was trace_uuid, use trace_uuid_msb and trace_uuid_lsb instead. reserved 26; // An identifier clients can use to tie this trace to other logging. // DEPRECATED as per v32. See TracePacket.trace_uuid for the authoritative // Trace UUID. If this field is set, the tracing service will respect the // requested UUID (i.e. TracePacket.trace_uuid == this field) but only if // gap-less snapshotting is not used. optional int64 trace_uuid_msb = 27 [deprecated = true]; optional int64 trace_uuid_lsb = 28 [deprecated = true]; // When set applies a post-filter to the trace contents using the filter // provided. The filter is applied at ReadBuffers() time and works both in the // case of IPC readback and write_into_file. This filter can be generated // using `tools/proto_filter -s schema.proto -F filter_out.bytes` or // `-T filter_out.escaped_string` (for .pbtx). See go/trace-filtering for // design. // // Introduced in Android S, but it was broken (b/195065199). Reintroduced in // Android T with a different field number. Updated in Android U with a new // bytecode version which supports string filtering. message TraceFilter { // ========================= // Filter bytecode. // ========================= // The bytecode as implemented in Android T. optional bytes bytecode = 1; // The bytecode as implemented in Android U. Adds support for string // filtering. optional bytes bytecode_v2 = 2; // ========================= // String filtering // ========================= // The principles and terminology of string filtering is heavily inspired by // iptables. A "rule" decide how strings should be filtered. Each rule // contains a "policy" which indicates the algorithm to use for filtering. // A "chain" is a list of rules which will be sequentially checked against // each string. // // The first rule which applies to the string terminates filtering for that // string. If no rules apply, the string is left unchanged. // A policy specifies which algorithm should be used for filtering the // string. enum StringFilterPolicy { SFP_UNSPECIFIED = 0; // Tries to match the string field against |regex_pattern|. If it // matches, all matching groups are "redacted" (i.e. replaced with a // constant string) and filtering is terminated (i.e. no further rules are // checked). If it doesn't match, the string is left unchanged and the // next rule in chain is considered. SFP_MATCH_REDACT_GROUPS = 1; // Like |SFP_MATCH_REDACT_GROUPS| but tries to do some pre-work before // checking the regex. Specifically, it tries to parse the string field as // an atrace tracepoint and checks if the post-tgid field starts with // |atrace_post_tgid_starts_with|. The regex matching is only performed if // this check succeeds. SFP_ATRACE_MATCH_REDACT_GROUPS = 2; // Tries to match the string field against |regex_pattern|. If it // matches, filtering is terminated (i.e. no further rules are checked). // If it doesn't match, the string is left unchanged and the next rule in // chain is considered. SFP_MATCH_BREAK = 3; // Like |SFP_MATCH_BREAK| but tries to do some pre-work before checking // the regex. Specifically, it tries to parse the string field as an // atrace tracepoint and checks if the post-tgid field starts with // |atrace_post_tgid_starts_with|. The regex matching is only performed if // this check succeeds. SFP_ATRACE_MATCH_BREAK = 4; // Tries to repeatedly search (i.e. find substrings of) the string field // with |regex_pattern|. For each match, redacts any matching groups (i.e. // replaced with a constant string). Once there are no further matches, // filtering is terminated (i.e. no further rules are checked). // // Note that this is policy is a "search" policy not a "match" policy // unlike the above policies: // * Match policies require matching the full string i.e. there is an // implicit leading `^` and trailing `$`. // * Search policies perform repeated partial matching of the string // e.g. // - String: `foo=aaa,bar=123,foo=bbb,baz=456` // - Pattern: `foo=(\d+)` // - Output: `foo=P6O,bar=123,foo=P6O,baz=456` // where P6O is the redaction string // // All of this is only performed after some pre-work where we try to parse // the string field as an atrace tracepoint and check if the post-tgid // field starts with |atrace_post_tgid_starts_with|. // // If there are no partial matches, the string is left unchanged and the // next rule in chain is considered. SFP_ATRACE_REPEATED_SEARCH_REDACT_GROUPS = 5; } // A rule specifies how strings should be filtered. message StringFilterRule { // The policy (i.e. algorithm) dictating how strings matching this rule // should be handled. optional StringFilterPolicy policy = 1; // The regex pattern used to match against each string. optional string regex_pattern = 2; // The string which should appear after the tgid in atrace tracepoint // strings. optional string atrace_payload_starts_with = 3; } // A chain is a list of rules which string will be sequentially checked // against. message StringFilterChain { repeated StringFilterRule rules = 1; } optional StringFilterChain string_filter_chain = 3; } // old field number for trace_filter reserved 32; optional TraceFilter trace_filter = 33; // Android-only. Not for general use. If set, reports the trace to the // Android framework. This field is read by perfetto_cmd, rather than the // tracing service. This field must be set when passing the --upload flag to // perfetto_cmd. message AndroidReportConfig { // In this message, either: // * |reporter_service_package| and |reporter_service_class| must be set. // * |skip_reporting| must be explicitly set to true. optional string reporter_service_package = 1; optional string reporter_service_class = 2; // If true, then skips reporting the trace to Android framework. // // This flag is useful in testing (e.g. Perfetto-statsd integration tests) // or when we explicitly don't want to report traces to the framework even // when they usually would (e.g. configs deployed using statsd but only // used for inclusion in bugreports using |bugreport_score|). // // The motivation for having this flag, instead of just not setting // |framework_report_config|, is prevent accidents where // |framework_report_config| is omitted by mistake. optional bool skip_report = 3; // If true, will direct the Android framework to read the data in trace // file and pass it to the reporter class over a pipe instead of passing // the file descriptor directly. // // This flag is needed because the Android test framework does not // currently support priv-app helper apps (in terms of SELinux) and we // really don't want to add an allow rule for untrusted_app to receive // trace fds. // // Because of this, we instead will direct the framework to create a new // pipe and pass this to the reporter process instead. As the pipe is // created by the framework, we won't have any problems with SELinux // (system_server is already allowed to pass pipe fds, even // to untrusted apps). // // As the name suggests this option *MUST* only be used for testing. // Note that the framework will reject (and drop) files which are too // large both for simplicity and to be minimize the amount of data we // pass to a non-priv app (note that the framework will still check // manifest permissions even though SELinux permissions are worked around). optional bool use_pipe_in_framework_for_testing = 4; } optional AndroidReportConfig android_report_config = 34; // If set, delays the start of tracing by a random duration. The duration is // chosen from a uniform distribution between the specified minimum and // maximum. // Note: this delay is implemented by perfetto_cmd *not* by traced so will // not work if you communicate with traced directly over the consumer API. // Introduced in Android T. message CmdTraceStartDelay { optional uint32 min_delay_ms = 1; optional uint32 max_delay_ms = 2; } optional CmdTraceStartDelay cmd_trace_start_delay = 35; // When non-empty, ensures that for a each semaphore named `name at most // `max_other_session_count`` *other* sessions (whose value is taken of the // minimum of all values specified by this config or any already-running // session) can be be running. // // If a semaphore "acquisition" fails, EnableTracing will return an error // and the tracing session will not be started (or elgible to start in // the case of deferred sessions). // // This is easiest to explain with an example. Suppose the tracing service has // the following active tracing sessions: // S1 = [{name=foo, max_other_session_count=2}, // {name=bar, max_other_session_count=0}] // S2 = [{name=foo, max_other_session_count=1}, // {name=baz, max_other_session_count=1}] // // Then, for a new session, the following would be the expected behaviour of // EnableSession given the state of `session_semaphores`. // Q: session_semaphores = [] // A: Allowed because it does not specify any semaphores. Will be allowed // no matter the state of any other tracing session. // Q: session_semaphores = [{name=baz, max_other_session_count=1}] // A: Allowed because both S2 and this config specify // max_other_session_count=1 for baz. // Q: session_semaphores = [{name=foo, max_other_session_count=3}] // A: Denied because S2 specified max_other_session_count=1 for foo and S1 // takes that slot. // Q: session_semaphores = [{name=bar, max_other_session_count=0}] // A: Denied because S1 takes the the slot specified by both S1 and // this config. // // Introduced in 24Q3 (Android V). message SessionSemaphore { // The name of the semaphore. Acts as a unique identifier across all // tracing sessions (including the one being started). optional string name = 1; // The maximum number of *other* sesssions which specify the same semaphore // which can be active. The minimum of this value across all tracing // sessions and the value specified by the config is used when deciding // whether the tracing session can be started. optional uint64 max_other_session_count = 2; } repeated SessionSemaphore session_semaphores = 39; }