SurfaceFlinger: Add support for continuous dumpsys to file.

- Collect dumpsys to an outfile file when triggered.
- Collect dumpsys before calling Prepare on hwc module in
  each draw cycle. Recollect dumpsys if Commit goes through
  successfully and replace former dumpsys with this.
- Wrap around if file size reaches appx 20 MB.
- Generate output file at /data/misc/display/dumpsys.txt
- Syntax:
      adb shell dumpsys SurfaceFlinger --file [--no-limit]
          --file : Ouput dumpsys to file
          --no-limit : Do not wrap around, keep appending

      Use same command to trigger start and end of dumping.
- Output format:
      | start code | after commit? | time stamp | dump size | dump data |

CRs-Fixed: 947084

Change-Id: Ie520f51c69757aeec88b9400688a7f3271472349

1 files changed, 4 insertions, 0 deletions

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 43a0bd8..a457019 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -1081,6 +1081,8 @@ void SurfaceFlinger::postComposition()
         mAnimFrameTracker.advanceFrame();
     }
 
+    dumpDrawCycle(false);
+
     if (hw->getPowerMode() == HWC_POWER_MODE_OFF) {
         return;
     }
@@ -1248,6 +1250,8 @@ void SurfaceFlinger::setUpHWComposer() {
             }
         }
 
+        dumpDrawCycle(true);
+
         status_t err = hwc.prepare();
         ALOGE_IF(err, "HWComposer::prepare failed (%s)", strerror(-err));