Android的Systrace跟踪文件格式(Android Systrace Trace File

Android的systrace工具，通过ADB称atrace工具。不过，我不很了解的痕迹文件的格式。显然，这是非常相似，但存在一些不同的Linux ftrace工具。主要的区别是不使用System.Map文件，但它包含了所有的信息到跟踪文件。另外，还有一些新的C |是机器人将特定的E项。

有关于这格式Android源代码的一些信息： http://androidxref.com/4.1.1/xref/external/chromium-trace/src/tracing/linux_perf_importer.js

然而，该文档中，我们可以读取的格式属于Linux的逆足工具。我不这么认为，Linux的PERF给作为输出一个非常不同的格式...（除非一些特殊的配置是活跃...）

我的问题是：是否有人知道我在哪里可以找到有关与亚行atrace工具生成的Android跟踪文件的正式文件？

这是格式熟悉吗？

# tracer: nop
#
# entries-in-buffer/entries-written: 66427/66427   #P:2
#
#                              _-----=> irqs-off
#                             / _----=> need-resched
#                            | / _---=> hardirq/softirq
#                            || / _--=> preempt-depth
#                            ||| /     delay
#           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
#              | |       |   ||||       |         |
          atrace-1724  [000] d..3 14186.680000: sched_switch: prev_comm=atrace prev_pid=1724 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120
          <idle>-0     [000] d.h7 14186.690000: sched_wakeup: comm=tfm_b6bcf800 pid=1714 prio=35 success=1 target_cpu=000
          <idle>-0     [000] d..3 14186.690000: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=tfm_b6bcf800 next_pid=1714 next_prio=35
    tfm_b6bcf800-1714  [000] d..3 14186.690000: sched_switch: prev_comm=tfm_b6bcf800 prev_pid=1714 prev_prio=35 prev_state=D|W ==> next_comm=swapper/0 next_pid=0 next_prio=120
          <idle>-0     [001] d.h3 14186.690000: sched_wakeup: comm=Player Aud Mixe pid=146 prio=35 success=1 target_cpu=001
          <idle>-0     [001] d..3 14186.690000: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=Player Aud Mixe next_pid=146 next_prio=35
 Player Aud Mixe-146   [001] d..3 14186.690000: sched_switch: prev_comm=Player Aud Mixe prev_pid=146 prev_prio=35 prev_state=D ==> next_comm=swapper/1 next_pid=0 next_prio=120
          <idle>-0     [001] d.h3 14186.690000: sched_wakeup: comm=Player Aud Mixe pid=146 prio=35 success=1 target_cpu=001
          <idle>-0     [001] d..3 14186.690000: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=Player Aud Mixe next_pid=146 next_prio=35
 Player Aud Mixe-146   [001] d..3 14186.690000: sched_switch: prev_comm=Player Aud Mixe prev_pid=146 prev_prio=35 prev_state=S ==> next_comm=swapper/1 next_pid=0 next_prio=120
          <idle>-0     [001] d.h3 14186.700000: sched_wakeup: comm=Player Aud Mixe pid=146 prio=35 success=1 target_cpu=001
          <idle>-0     [001] d..3 14186.700000: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=Player Aud Mixe next_pid=146 next_prio=35
  EventThread-110   [001] d..5 14190.100000: sched_wakeup: comm=SurfaceFlinger pid=103 prio=112 success=1 target_cpu=001
     EventThread-110   [001] d..3 14190.100000: sched_switch: prev_comm=EventThread prev_pid=110 prev_prio=111 prev_state=S ==> next_comm=SurfaceFlinger next_pid=103 next_prio=112
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|onMessageReceived
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|handleTransaction
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|doTransaction
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: E
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: E
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|handleMessageInvalidate
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: E
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: E
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|onMessageReceived
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|handleMessageRefresh
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|rebuildLayerStacks
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|computeVisibleRegions
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: E
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: E
  SurfaceFlinger-103   [001] ...1 14190.100000: tracing_mark_write: B|96|doComposition
  SurfaceFlinger-103   [001] d.h4 14190.100000: sched_wakeup: comm=surfaceflinger pid=96 prio=120 success=1 target_cpu=001
  SurfaceFlinger-103   [001] d..3 14190.100000: sched_switch: prev_comm=SurfaceFlinger prev_pid=103 prev_prio=112 prev_state=R ==> next_comm=surfaceflinger next_pid=96 next_prio=120

提前致谢！

Answer 1:

好了，现在是肯定的：格式属于ftrace工具。 Android的atrace是ftrace构建的扩展，以方便配置。

从ftrace正式文件，显示该输出格式可以直接通过它以如下方式制备：

root@adroid:# echo 1 > /sys/kernel/debug/tracing/events/sched/sched_switch/enable
root@adroid:# echo 1 > /sys/kernel/debug/tracing/tracing_on
root@adroid:# cat /sys/kernel/debug/tracing/trace > mytracefile.txt
root@adroid:# echo 0 > /sys/kernel/debug/tracing/tracing_on
root@adroid:# echo 0 > /sys/kernel/debug/tracing/events/sched/sched_switch/enable

：在官方文档http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/trace/ftrace.txt

# cat trace
# tracer: nop
#
# entries-in-buffer/entries-written: 77/77   #P:8
#
#                              _-----=> irqs-off
#                             / _----=> need-resched
#                            | / _---=> hardirq/softirq
#                            || / _--=> preempt-depth
#                            ||| /     delay
#           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
#              | |       |   ||||       |         |
          <idle>-0     [007] d...  2440.707395: sched_switch: prev_comm=swapper/7 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=snapshot-test-2 next_pid=2243 next_prio=120
 snapshot-test-2-2229  [002] d...  2440.707438: sched_switch: prev_comm=snapshot-test-2 prev_pid=2229 prev_prio=120 prev_state=S ==> next_comm=swapper/2 next_pid=0 next_prio=120
[...]

问候，

Answer 2:

伟大的职位不过不要忘了安装调试的文件系统，

"mount -t debugfs none /sys/kernel/debug" or 
"mount -o rw,remount -t debugfs none /sys/kernel/debug"

否则你不会得到像

“错误打开/ SYS /内核/调试/跟踪/选项/覆盖：没有这样的文件或目录”

运行atrace时

一些更多的有用的信息在这里http://rahulonblog.blogspot.se/2013/06/how-to-enable-debugfs-in-kernel.html