Don't place large objects on the stack

Bug: 25020816
Change-Id: Ife4da9fc3000e645f654f2eb28b37ad3a89d61f9

1 files changed, 13 insertions, 5 deletions

diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index e1e4980..ecdbf43 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -4470,8 +4470,12 @@ void AudioFlinger::MixerThread::dumpInternals(int fd, const Vector<String16>& ar
     dprintf(fd, "  AudioMixer tracks: 0x%08x\n", mAudioMixer->trackNames());
 
     // Make a non-atomic copy of fast mixer dump state so it won't change underneath us
-    const FastMixerDumpState copy(mFastMixerDumpState);
-    copy.dump(fd);
+    // while we are dumping it.  It may be inconsistent, but it won't mutate!
+    // This is a large object so we place it on the heap.
+    // FIXME 25972958: Need an intelligent copy constructor that does not touch unused pages.
+    const FastMixerDumpState *copy = new FastMixerDumpState(mFastMixerDumpState);
+    copy->dump(fd);
+    delete copy;
 
 #ifdef STATE_QUEUE_DUMP
     // Similar for state queue
@@ -6460,9 +6464,13 @@ void AudioFlinger::RecordThread::dumpInternals(int fd, const Vector<String16>& a
     dprintf(fd, "  Fast capture thread: %s\n", hasFastCapture() ? "yes" : "no");
     dprintf(fd, "  Fast track available: %s\n", mFastTrackAvail ? "yes" : "no");
 
-    //  Make a non-atomic copy of fast capture dump state so it won't change underneath us
-    const FastCaptureDumpState copy(mFastCaptureDumpState);
-    copy.dump(fd);
+    // Make a non-atomic copy of fast capture dump state so it won't change underneath us
+    // while we are dumping it.  It may be inconsistent, but it won't mutate!
+    // This is a large object so we place it on the heap.
+    // FIXME 25972958: Need an intelligent copy constructor that does not touch unused pages.
+    const FastCaptureDumpState *copy = new FastCaptureDumpState(mFastCaptureDumpState);
+    copy->dump(fd);
+    delete copy;
 }
 
 void AudioFlinger::RecordThread::dumpTracks(int fd, const Vector<String16>& args __unused)