Question

我知道之前有人问过，但我害怕＆＃34; systrace使用扩展ftrace的atrace，所以在这里检查ftrace格式＆＃34;对我来说还不够。我正在了解一些systrace特定标签/格式的更多细节。我有一些我没有信心的猜测，因此我需要一个真正知道他们确认/否定的人。

以下是我在trace.html中找到的一些结果。

# tracer: nop\n\
#\n\
# entries-in-buffer/entries-written: 393636/393636   #P:1\n\
#\n\
#                              _-----=> irqs-off\n\
#                             / _----=> need-resched\n\
#                            | / _---=> hardirq/softirq\n\
#                            || / _--=> preempt-depth\n\
#                            ||| /     delay\n\
#           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION\n\
#              | |       |   ||||       |         |\n\
          atrace-27768 [000] ...2 17184.509740: sched_switch: prev_comm=atrace prev_pid=27768 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
      Thread-117-16753 [001] ...1 17184.510251: tracing_mark_write: B|4237|eglSwapBuffers\n\
          <idle>-0     [000] d.h4 17184.510329: sched_wakeup: comm=AudioOut_2 pid=608 prio=101 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.510338: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=AudioOut_2 next_pid=608 next_prio=101\n\
      AudioOut_2-608   [000] d..4 17184.510393: sched_wakeup: comm=AudioTrack pid=16778 prio=104 success=1 target_cpu=000\n\
      AudioOut_2-608   [000] ...2 17184.510446: sched_switch: prev_comm=AudioOut_2 prev_pid=608 prev_prio=101 prev_state=S ==> next_comm=AudioTrack next_pid=16778 next_prio=104\n\
      Thread-117-16753 [001] ...1 17184.510610: tracing_mark_write: B|4237|queueBuffer\n\
      Thread-117-16753 [001] d..4 17184.510648: sched_wakeup: comm=Binder_2 pid=189 prio=120 success=1 target_cpu=001\n\
      Thread-117-16753 [001] ...2 17184.510656: sched_switch: prev_comm=Thread-117 prev_pid=16753 prev_prio=120 prev_state=R+ ==> next_comm=Binder_2 next_pid=189 next_prio=120\n\
        Binder_2-189   [001] ...2 17184.510664: sched_switch: prev_comm=Binder_2 prev_pid=189 prev_prio=120 prev_state=D ==> next_comm=Thread-117 next_pid=16753 next_prio=120\n\
      Thread-117-16753 [001] d..4 17184.510670: sched_wakeup: comm=Binder_2 pid=189 prio=120 success=1 target_cpu=001\n\
      Thread-117-16753 [001] ...2 17184.510673: sched_switch: prev_comm=Thread-117 prev_pid=16753 prev_prio=120 prev_state=R+ ==> next_comm=Binder_2 next_pid=189 next_prio=120\n\
        Binder_2-189   [001] ...1 17184.510722: tracing_mark_write: B|147|queueBuffer\n\
        Binder_2-189   [001] ...1 17184.510729: tracing_mark_write: B|147|SurfaceView: 0\n\
        Binder_2-189   [001] ...1 17184.510734: tracing_mark_write: E\n\
        Binder_2-189   [001] ...1 17184.510753: tracing_mark_write: C|147|SurfaceView|1\n\
        Binder_2-189   [001] d..4 17184.510772: sched_wakeup: comm=EventThread pid=255 prio=111 success=1 target_cpu=001\n\
        Binder_2-189   [001] ...1 17184.510781: tracing_mark_write: E\n\
        Binder_2-189   [001] ...2 17184.510810: sched_switch: prev_comm=Binder_2 prev_pid=189 prev_prio=120 prev_state=S ==> next_comm=EventThread next_pid=255 next_prio=111\n\
     EventThread-255   [001] d..4 17184.510828: sched_wakeup: comm=DispSync pid=186 prio=111 success=1 target_cpu=001\n\
     EventThread-255   [001] ...1 17184.510840: tracing_mark_write: C|147|VsyncOn|1\n\
     EventThread-255   [001] ...2 17184.510852: sched_switch: prev_comm=EventThread prev_pid=255 prev_prio=111 prev_state=S ==> next_comm=DispSync next_pid=186 next_prio=111\n\
        DispSync-186   [001] ...2 17184.510867: sched_switch: prev_comm=DispSync prev_pid=186 prev_prio=111 prev_state=S ==> next_comm=Thread-117 next_pid=16753 next_prio=120\n\
      Thread-117-16753 [001] ...1 17184.510885: tracing_mark_write: E\n\
      Thread-117-16753 [001] ...1 17184.510893: tracing_mark_write: B|4237|query\n\
      Thread-117-16753 [001] ...1 17184.510899: tracing_mark_write: E\n\
      Thread-117-16753 [001] ...1 17184.510906: tracing_mark_write: B|4237|query\n\
      Thread-117-16753 [001] ...1 17184.510911: tracing_mark_write: E\n\
      Thread-117-16753 [001] ...1 17184.510924: tracing_mark_write: E\n\
      AudioTrack-16778 [000] d.h7 17184.510984: sched_wakeup: comm=FastMixer pid=330 prio=96 success=1 target_cpu=000\n\
      AudioTrack-16778 [000] ...2 17184.511000: sched_switch: prev_comm=AudioTrack prev_pid=16778 prev_prio=104 prev_state=R+ ==> next_comm=FastMixer next_pid=330 next_prio=96\n\
      Thread-117-16753 [001] ...1 17184.511012: tracing_mark_write: B|4237|dequeueBuffer\n\
      Thread-117-16753 [001] d..4 17184.511034: sched_wakeup: comm=Binder_1 pid=185 prio=120 success=1 target_cpu=001\n\
      Thread-117-16753 [001] ...2 17184.511041: sched_switch: prev_comm=Thread-117 prev_pid=16753 prev_prio=120 prev_state=R+ ==> next_comm=Binder_1 next_pid=185 next_prio=120\n\
        Binder_1-185   [001] ...2 17184.511053: sched_switch: prev_comm=Binder_1 prev_pid=185 prev_prio=120 prev_state=D ==> next_comm=Thread-117 next_pid=16753 next_prio=120\n\
      Thread-117-16753 [001] d..4 17184.511059: sched_wakeup: comm=Binder_1 pid=185 prio=120 success=1 target_cpu=001\n\
      Thread-117-16753 [001] ...2 17184.511062: sched_switch: prev_comm=Thread-117 prev_pid=16753 prev_prio=120 prev_state=R+ ==> next_comm=Binder_1 next_pid=185 next_prio=120\n\
       FastMixer-330   [000] ...2 17184.511070: sched_switch: prev_comm=FastMixer prev_pid=330 prev_prio=96 prev_state=S ==> next_comm=AudioTrack next_pid=16778 next_prio=104\n\
      AudioTrack-16778 [000] ...2 17184.511087: sched_switch: prev_comm=AudioTrack prev_pid=16778 prev_prio=104 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
        Binder_1-185   [001] ...1 17184.511093: tracing_mark_write: B|147|dequeueBuffer\n\
        Binder_1-185   [001] ...1 17184.511102: tracing_mark_write: B|147|SurfaceView: 1\n\
        Binder_1-185   [001] ...1 17184.511105: tracing_mark_write: E\n\
        Binder_1-185   [001] ...1 17184.511110: tracing_mark_write: E\n\
        Binder_1-185   [001] ...2 17184.511131: sched_switch: prev_comm=Binder_1 prev_pid=185 prev_prio=120 prev_state=S ==> next_comm=Thread-117 next_pid=16753 next_prio=120\n\
      Thread-117-16753 [001] ...1 17184.511143: tracing_mark_write: E\n\
          <idle>-0     [000] d.h4 17184.512011: sched_wakeup: comm=Thread-117 pid=16780 prio=120 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.512021: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=Thread-117 next_pid=16780 next_prio=120\n\
      Thread-117-16780 [000] ...2 17184.512047: sched_switch: prev_comm=Thread-117 prev_pid=16780 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
          <idle>-0     [000] d.h4 17184.513414: sched_wakeup: comm=Thread-117 pid=17201 prio=120 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.513425: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=Thread-117 next_pid=17201 next_prio=120\n\
      Thread-117-17201 [000] ...2 17184.513441: sched_switch: prev_comm=Thread-117 prev_pid=17201 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
      Thread-117-16753 [001] ...2 17184.516369: sched_switch: prev_comm=Thread-117 prev_pid=16753 prev_prio=120 prev_state=S ==> next_comm=swapper/1 next_pid=0 next_prio=120\n\
          <idle>-0     [000] d.h6 17184.517936: sched_wakeup: comm=kworker/0:3 pid=27267 prio=120 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.517947: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/0:3 next_pid=27267 next_prio=120\n\
     kworker/0:3-27267 [000] ...2 17184.518045: sched_switch: prev_comm=kworker/0:3 prev_pid=27267 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
          <idle>-0     [000] d.h7 17184.520977: sched_wakeup: comm=FastMixer pid=330 prio=96 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.520986: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=FastMixer next_pid=330 next_prio=96\n\
       FastMixer-330   [000] ...2 17184.521041: sched_switch: prev_comm=FastMixer prev_pid=330 prev_prio=96 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
          <idle>-0     [000] d.h6 17184.521117: sched_wakeup: comm=kworker/0:3 pid=27267 prio=120 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.521122: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/0:3 next_pid=27267 next_prio=120\n\
     kworker/0:3-27267 [000] d..4 17184.521130: sched_wakeup: comm=hwc_eventmon pid=246 prio=100 success=1 target_cpu=000\n\
     kworker/0:3-27267 [000] ...2 17184.521135: sched_switch: prev_comm=kworker/0:3 prev_pid=27267 prev_prio=120 prev_state=S ==> next_comm=hwc_eventmon next_pid=246 next_prio=100\n\
    hwc_eventmon-246   [000] ...2 17184.521155: sched_switch: prev_comm=hwc_eventmon prev_pid=246 prev_prio=100 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
          <idle>-0     [000] d.s5 17184.521414: sched_wakeup: comm=cfinteractive pid=88 prio=0 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.521420: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=cfinteractive next_pid=88 next_prio=0\n\
   cfinteractive-88    [000] ...2 17184.521440: sched_switch: prev_comm=cfinteractive prev_pid=88 prev_prio=0 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\
          <idle>-0     [001] d.h4 17184.525814: sched_wakeup: comm=DispSync pid=186 prio=111 success=1 target_cpu=001\n\
          <idle>-0     [001] ...2 17184.525821: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=DispSync next_pid=186 next_prio=111\n\
        DispSync-186   [001] d..4 17184.525842: sched_wakeup: comm=EventThread pid=255 prio=111 success=1 target_cpu=001\n\
        DispSync-186   [001] ...2 17184.525851: sched_switch: prev_comm=DispSync prev_pid=186 prev_prio=111 prev_state=S ==> next_comm=EventThread next_pid=255 next_prio=111\n\
          <idle>-0     [000] d.h3 17184.525884: sched_wakeup: comm=surfaceflinger pid=147 prio=112 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.525890: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=surfaceflinger next_pid=147 next_prio=112\n\
     EventThread-255   [001] ...2 17184.525892: sched_switch: prev_comm=EventThread prev_pid=255 prev_prio=111 prev_state=S ==> next_comm=swapper/1 next_pid=0 next_prio=120\n\

Q1：为什么＆＃34;线程＆＃34;带有不同的PID，有时可以安排在不同的CPU上运行，例如螺纹117？什么＆＃34;线程＆＃34;真的是这里的意思吗？

        Binder_1-185   [001] ...2 17184.511131: sched_switch: prev_comm=Binder_1 prev_pid=185 prev_prio=120 prev_state=S ==> next_comm=Thread-117 next_pid=16753 next_prio=120\n\
      Thread-117-16753 [001] ...1 17184.511143: tracing_mark_write: E\n\
          <idle>-0     [000] d.h4 17184.512011: sched_wakeup: comm=Thread-117 pid=16780 prio=120 success=1 target_cpu=000\n\
          <idle>-0     [000] ...2 17184.512021: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=Thread-117 next_pid=16780 next_prio=120\n\
      Thread-117-16780 [000] ...2 17184.512047: sched_switch: prev_comm=Thread-117 prev_pid=16780 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120\n\

Q2：什么＆＃34; prev_state＆＃34; in＆＃34; sched_switch＆＃34;意思？什么＆＃34; S，D，R，R +＆＃34;分别参考这个变量？

Q3：＆＃34; tracing_mark_write＆＃34;使用B表示开头，C表示更改，E表示结束。但是E标签没有跟踪名称。如何确定它对应哪个B标签？它是否在调用堆栈样式LIFO中工作？如果是这样，那只有在＆＃34;线程＆＃34;是一个真正的线程，无法拆分为在两个CPU上连贯运行。这导致我们回到Q1。

感谢任何帮助！

Answer 1

A1：它显示了您在设备上ps -t看到的线程名称，该名称由进程设置。未命名的Dalvik线程命名为＆＃34; Thread-N＆＃34;，其中N是由Thread类跟踪的序列号（与Binder线程池创建的相同方式＆＃34; Binder_1＆＃34;）。所以＆＃34; 117＆＃34; in＆＃34; Thread-117＆＃34;与系统pid或tid没有任何关系;它正是调用线程的内容。它不能保证是唯一的 - 您可以在一个进程中或在单独的进程中拥有多个实例。

A2：状态与您在ps输出中看到的状态相同。请参阅Linux手册页＆＃34; PROCESS STATE CODES＆＃34;部分：

   D    uninterruptible sleep (usually IO)
   R    running or runnable (on run queue)
   S    interruptible sleep (waiting for an event to complete)
   ...

A3：是的，LIFO，单线程。这与公共android.os.Trace API相匹配。（是"asynchronous" traces的另一个（非公开）API，您提供相同的标记和＃34; Cookie＆＃34;用于开始和结束，但它是没有广泛使用。）

阅读systrace日志

1 个答案: