Fix the issue that makes GsiService::Cancel to block

The GsiService::Get shares the same mutex with other methods.
This makes the cancel method to block on the mutex.

Bug: 145891864
Test: open two terminals and execute commands below
  1st terminal gsi_tool install
  2nd terminal gsi_tool cancel

Change-Id: Ie458318013dfbbe11c831bf2eb0aa1132dceae30

1 files changed, 4 insertions, 2 deletions

diff --git a/gsi_service.cpp b/gsi_service.cpp
index 5ef4914..511b080 100644
--- a/gsi_service.cpp
+++ b/gsi_service.cpp
@@ -59,6 +59,8 @@ using android::base::WriteStringToFd;
 using android::base::WriteStringToFile;
 using android::dm::DeviceMapper;
 
+static std::mutex sInstanceLock;
+
 android::wp<GsiService> GsiService::sInstance;
 
 // Default userdata image size.
@@ -81,7 +83,7 @@ GsiService::GsiService(Gsid* parent) : parent_(parent) {
 }
 
 GsiService::~GsiService() {
-    std::lock_guard<std::mutex> guard(parent_->lock());
+    std::lock_guard<std::mutex> guard(sInstanceLock);
 
     if (sInstance == this) {
         // No more consumers, gracefully shut down gsid.
@@ -90,7 +92,7 @@ GsiService::~GsiService() {
 }
 
 android::sp<IGsiService> GsiService::Get(Gsid* parent) {
-    std::lock_guard<std::mutex> guard(parent->lock());
+    std::lock_guard<std::mutex> guard(sInstanceLock);
 
     android::sp<GsiService> service = sInstance.promote();
     if (!service) {