TheRock/rocm-systems/projects/rocprofiler-sdk/external/perfetto/docs/data-sources/system-log.md

Syscalls

The enter and exit of all syscalls can be tracked in Perfetto traces.

The following ftrace events need to added to the trace config to collect syscalls.

data_sources: {
    config {
        name: "linux.ftrace"
        ftrace_config {
            ftrace_events: "raw_syscalls/sys_enter"
            ftrace_events: "raw_syscalls/sys_exit"
        }
    }
}

Linux kernel tracing

Perfetto integrates with Linux kernel event tracing. While Perfetto has special support for some events (for example see CPU Scheduling) Perfetto can collect arbitrary events. This config collects four Linux kernel events:

data_sources {
  config {
    name: "linux.ftrace"
    ftrace_config {
      ftrace_events: "ftrace/print"
      ftrace_events: "sched/sched_switch"
      ftrace_events: "task/task_newtask"
      ftrace_events: "task/task_rename"
    }
  }
}

The full configuration options for ftrace can be seen in ftrace_config.proto.

Android system logs

Android logcat

Include Android Logcat messages in the trace and view them in conjunction with other trace data.

You can configure which log buffers are included in the trace. If no buffers are specified, all will be included.

data_sources: {
    config {
        name: "android.log"
        android_log_config {
            log_ids: LID_DEFAULT
            log_ids: LID_SYSTEM
            log_ids: LID_CRASH
        }
    }
}

You may also want to add filtering on a tags using the filter_tags parameter or set a min priority to be included in the trace using min_prio. For details about configuration options, see android_log_config.proto.

The logs can be investigated along with other information in the trace using the Perfetto UI as shown in the screenshot above.

If using the trace_processor, these logs will be in the android_logs table. To look at the logs with the tag ‘perfetto’ you would use the following query:

select * from android_logs where tag = "perfetto" order by ts

Android application tracing

You can enable atrace through Perfetto.

Add required categories to atrace_categories and set atrace_apps to a specific app to collect userspace annotations from that app.

data_sources: {
    config {
        name: "linux.ftrace"
        ftrace_config {
            atrace_categories: "view"
            atrace_categories: "webview"
            atrace_categories: "wm"
            atrace_categories: "am"
            atrace_categories: "sm"
            atrace_apps: "com.android.phone"
        }
    }
}