gpuservice: prevent hang in destruction

When initialization of bpf programs fail, the threads
here hang for 30s, which is too long to fuzz.

We can stop them, so the fuzzer progresses (and sometimes
hits the 1s timeout), but at least this is better.

Without this patch, on CF, the error that is occurring is:
> Failed to attach bpf program to power/gpu_work_period tracepoint [2(No such file or directory)]

Fixes: 318008019
Test: gpu_service_fuzzer

Change-Id: I0f2dbf911970f3cd5c736a5cd1697accc1e95937

5 files changed, 15 insertions, 1 deletions

diff --git a/services/gpuservice/GpuService.cpp b/services/gpuservice/GpuService.cpp
index 48d793a4d4..080e62b164 100644
--- a/services/gpuservice/GpuService.cpp
+++ b/services/gpuservice/GpuService.cpp
@@ -70,6 +70,9 @@ GpuService::GpuService()
 };
 
 GpuService::~GpuService() {
+    mGpuMem->stop();
+    mGpuWork->stop();
+
     mGpuWorkAsyncInitThread->join();
     mGpuMemAsyncInitThread->join();
 }
diff --git a/services/gpuservice/gpumem/GpuMem.cpp b/services/gpuservice/gpumem/GpuMem.cpp
index 141fe021ee..d0783df109 100644
--- a/services/gpuservice/gpumem/GpuMem.cpp
+++ b/services/gpuservice/gpumem/GpuMem.cpp
@@ -61,6 +61,7 @@ void GpuMem::initialize() {
             return;
         }
         // Retry until GPU driver loaded or timeout.
+        if (mStop.load()) return;
         sleep(1);
     }
 
diff --git a/services/gpuservice/gpumem/include/gpumem/GpuMem.h b/services/gpuservice/gpumem/include/gpumem/GpuMem.h
index 9aa74d6863..16b201f516 100644
--- a/services/gpuservice/gpumem/include/gpumem/GpuMem.h
+++ b/services/gpuservice/gpumem/include/gpumem/GpuMem.h
@@ -34,6 +34,7 @@ public:
     // dumpsys interface
     void dump(const Vector<String16>& args, std::string* result);
     bool isInitialized() { return mInitialized.load(); }
+    void stop() { mStop.store(true); }
 
     // Traverse the gpu memory total map to feed the callback function.
     void traverseGpuMemTotals(const std::function<void(int64_t ts, uint32_t gpuId, uint32_t pid,
@@ -48,6 +49,10 @@ private:
 
     // indicate whether ebpf has been initialized
     std::atomic<bool> mInitialized = false;
+
+    // whether initialization should be stopped
+    std::atomic<bool> mStop = false;
+
     // bpf map for GPU memory total data
     android::bpf::BpfMapRO<uint64_t, uint64_t> mGpuMemTotalMap;
 
diff --git a/services/gpuservice/gpuwork/GpuWork.cpp b/services/gpuservice/gpuwork/GpuWork.cpp
index fd703239e9..1a744abc6d 100644
--- a/services/gpuservice/gpuwork/GpuWork.cpp
+++ b/services/gpuservice/gpuwork/GpuWork.cpp
@@ -243,6 +243,7 @@ bool GpuWork::attachTracepoint(const char* programPath, const char* tracepointGr
             return false;
         }
         // Retry until GPU driver loaded or timeout.
+        if (mStop.load()) return false;
         sleep(1);
         errno = 0;
     }
diff --git a/services/gpuservice/gpuwork/include/gpuwork/GpuWork.h b/services/gpuservice/gpuwork/include/gpuwork/GpuWork.h
index cece9999c6..e70da540b9 100644
--- a/services/gpuservice/gpuwork/include/gpuwork/GpuWork.h
+++ b/services/gpuservice/gpuwork/include/gpuwork/GpuWork.h
@@ -40,6 +40,7 @@ public:
     ~GpuWork();
 
     void initialize();
+    void stop() { mStop.store(true); }
 
     // Dumps the GPU work information.
     void dump(const Vector<String16>& args, std::string* result);
@@ -47,7 +48,7 @@ public:
 private:
     // Attaches tracepoint |tracepoint_group|/|tracepoint_name| to BPF program at path
     // |program_path|. The tracepoint is also enabled.
-    static bool attachTracepoint(const char* program_path, const char* tracepoint_group,
+    bool attachTracepoint(const char* program_path, const char* tracepoint_group,
                                  const char* tracepoint_name);
 
     // Native atom puller callback registered in statsd.
@@ -80,6 +81,9 @@ private:
     // Indicates whether our eBPF components have been initialized.
     std::atomic<bool> mInitialized = false;
 
+    // Indicates whether eBPF initialization should be stopped.
+    std::atomic<bool> mStop = false;
+
     // A thread that periodically checks whether |mGpuWorkMap| is nearly full
     // and, if so, clears it.
     std::thread mMapClearerThread;