rename binder services main thread to Binder_*

When a binder service's main thread joins the thread pool
it retains its name (whatever the exec name was), which is
very confusing in systrace.

we now rename that thread just like its friends in the
thread pool.

Change-Id: Ibb3b6ff07304b247cfc6fb1694e72350c579513e

include/binder/BinderService.h

@@ -36,13 +36,18 @@ class BinderService
 public:
     static status_t publish(bool allowIsolated = false) {
         sp<IServiceManager> sm(defaultServiceManager());
-        return sm->addService(String16(SERVICE::getServiceName()), new SERVICE(), allowIsolated);
+        return sm->addService(
+                String16(SERVICE::getServiceName()),
+                new SERVICE(), allowIsolated);
     }
 
     static void publishAndJoinThreadPool(bool allowIsolated = false) {
         sp<IServiceManager> sm(defaultServiceManager());
-        sm->addService(String16(SERVICE::getServiceName()), new SERVICE(), allowIsolated);
+        sm->addService(
+                String16(SERVICE::getServiceName()),
+                new SERVICE(), allowIsolated);
         ProcessState::self()->startThreadPool();
+        ProcessState::self()->giveThreadPoolName();
         IPCThreadState::self()->joinThreadPool();
     }
 

include/binder/ProcessState.h

@@ -71,6 +71,7 @@ public:
             void                spawnPooledThread(bool isMain);
             
             status_t            setThreadPoolMaxThreadCount(size_t maxThreads);
+            void                giveThreadPoolName();
 
 private:
     friend class IPCThreadState;
@@ -80,6 +81,7 @@ private:
 
                                 ProcessState(const ProcessState& o);
             ProcessState&       operator=(const ProcessState& o);
+            String8             makeBinderThreadName();
             
             struct handle_entry {
                 IBinder* binder;

include/utils/AndroidThreads.h

@@ -56,6 +56,9 @@ extern int androidCreateRawThreadEtc(android_thread_func_t entryFunction,
                                      size_t threadStackSize,
                                      android_thread_id_t *threadId);
 
+// set the same of the running thread
+extern void androidSetThreadName(const char* name);
+
 // Used by the Java Runtime to control how threads are created, so that
 // they can be proper and lovely Java threads.
 typedef int (*android_create_thread_fn)(android_thread_func_t entryFunction,

libs/binder/ProcessState.cpp

@@ -283,15 +283,20 @@ void ProcessState::setArgV0(const char* txt)
     }
 }
 
+String8 ProcessState::makeBinderThreadName() {
+    int32_t s = android_atomic_add(1, &mThreadPoolSeq);
+    String8 name;
+    name.appendFormat("Binder_%X", s);
+    return name;
+}
+
 void ProcessState::spawnPooledThread(bool isMain)
 {
     if (mThreadPoolStarted) {
-        int32_t s = android_atomic_add(1, &mThreadPoolSeq);
-        char buf[16];
-        snprintf(buf, sizeof(buf), "Binder_%X", s);
-        ALOGV("Spawning new pooled thread, name=%s\n", buf);
+        String8 name = makeBinderThreadName();
+        ALOGV("Spawning new pooled thread, name=%s\n", name.string());
         sp<Thread> t = new PoolThread(isMain);
-        t->run(buf);
+        t->run(name.string());
     }
 }
 
@@ -304,6 +309,10 @@ status_t ProcessState::setThreadPoolMaxThreadCount(size_t maxThreads) {
     return result;
 }
 
+void ProcessState::giveThreadPoolName() {
+    androidSetThreadName( makeBinderThreadName().string() );
+}
+
 static int open_driver()
 {
     int fd = open("/dev/binder", O_RDWR);

libs/utils/Threads.cpp

@@ -109,30 +109,34 @@ struct thread_data_t {
         }
         
         if (name) {
-#if defined(HAVE_PRCTL)
-            // Mac OS doesn't have this, and we build libutil for the host too
-            int hasAt = 0;
-            int hasDot = 0;
-            char *s = name;
-            while (*s) {
-                if (*s == '.') hasDot = 1;
-                else if (*s == '@') hasAt = 1;
-                s++;
-            }
-            int len = s - name;
-            if (len < 15 || hasAt || !hasDot) {
-                s = name;
-            } else {
-                s = name + len - 15;
-            }
-            prctl(PR_SET_NAME, (unsigned long) s, 0, 0, 0);
-#endif
+            androidSetThreadName(name);
             free(name);
         }
         return f(u);
     }
 };
 
+void androidSetThreadName(const char* name) {
+#if defined(HAVE_PRCTL)
+    // Mac OS doesn't have this, and we build libutil for the host too
+    int hasAt = 0;
+    int hasDot = 0;
+    const char *s = name;
+    while (*s) {
+        if (*s == '.') hasDot = 1;
+        else if (*s == '@') hasAt = 1;
+        s++;
+    }
+    int len = s - name;
+    if (len < 15 || hasAt || !hasDot) {
+        s = name;
+    } else {
+        s = name + len - 15;
+    }
+    prctl(PR_SET_NAME, (unsigned long) s, 0, 0, 0);
+#endif
+}
+
 int androidCreateRawThreadEtc(android_thread_func_t entryFunction,
                                void *userData,
                                const char* threadName,