Merge "Fix dumpDebugInfo blocked and phone hanging" am: 7cde9f29b4 am: 95873b656c am: 0b186a3b43

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/2229637

Change-Id: I185a2c187b44bb6cd5629320ec10a995ec0d11b2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/services/surfaceflinger/DisplayHardware/AidlComposerHal.cpp b/services/surfaceflinger/DisplayHardware/AidlComposerHal.cpp
index 79dcd159d3..36512311d1 100644
--- a/services/surfaceflinger/DisplayHardware/AidlComposerHal.cpp
+++ b/services/surfaceflinger/DisplayHardware/AidlComposerHal.cpp
@@ -264,17 +264,21 @@ std::string AidlComposer::dumpDebugInfo() {
     }
 
     std::string str;
+    // Use other thread to read pipe to prevent
+    // pipe is full, making HWC be blocked in writing.
+    std::thread t([&]() {
+        base::ReadFdToString(pipefds[0], &str);
+    });
     const auto status = mAidlComposer->dump(pipefds[1], /*args*/ nullptr, /*numArgs*/ 0);
     // Close the write-end of the pipe to make sure that when reading from the
     // read-end we will get eof instead of blocking forever
     close(pipefds[1]);
 
-    if (status == STATUS_OK) {
-        base::ReadFdToString(pipefds[0], &str);
-    } else {
+    if (status != STATUS_OK) {
         ALOGE("dumpDebugInfo: dump failed: %d", status);
     }
 
+    t.join();
     close(pipefds[0]);
     return str;
 }