Android Systrace跟踪文件格式

Question

Android Systrace跟踪文件格式

7

Android的systrace工具，通过ADB调用atrace工具。然而，我并不是很理解跟踪文件的格式。显然，它非常类似于Linux ftrace工具，但也有一些不同之处。主要区别在于它没有使用System.Map文件，而是将所有信息都包含在跟踪文件中。此外，还有一些新的B|E条目是针对Android特定的。

在Android源代码中，有关这种格式的一些信息可以在以下网址找到：http://androidxref.com/4.1.1/xref/external/chromium-trace/src/tracing/linux_perf_importer.js

然而，在该文档中，我们可以读到这种格式属于Linux Perf 工具。我认为不是这样的，因为Linux Perf输出的格式非常不同（除非启用了某些特殊配置...）

我的问题是：是否有人知道在通过ADB生成的atrace跟踪文件中可以找到官方文档？

您是否熟悉这种格式？

# 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

Thanks in advance !

- Rodmar Conde

也许不完全符合您的需求，但这个链接可能会有所帮助：http://developer.android.com/tools/help/systrace.html - Peter L.

1

你用了哪个命令生成上面的日志？我找不到生成包含“tracing_mark_write: B|”和“tracing_mark_write: E”的行的命令。 - Duke

“atrace” 命令是 Android shell 控制台（adb）中的“隐藏”命令。通常由 “systrace” Python 脚本调用。我通过手动执行 “atrace” 获取了此日志。 - Rodmar Conde

2个回答

0

很棒的文章，但不要忘记挂载调试文件系统。

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

否则你将得不到类似于

“打开/sys/kernel/debug/tracing/options/overwrite时出错：没有这个文件或目录”

当运行atrace时。

这里有一些更有用的信息http://rahulonblog.blogspot.se/2013/06/how-to-enable-debugfs-in-kernel.html。

- janCoffee

网页内容由stack overflow 提供, 点击上面的

可以查看英文原文，
原文链接

- Rodmar Conde · Accepted Answer

现在可以确定：这种格式属于ftrace工具。 Android的atrace是ftrace构建的扩展，旨在简化配置。

ftrace的官方文档显示，可以通过以下方式直接生成此输出格式：

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

官方文档位于： 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
[...]

敬礼，