Include short name in systrace block name

Summary:
We log the soname in the systrace blocks, which in prod resolves to the name of the merged library. This leads to traces like https://fburl.com/tracery/5sr15q1q, where we know which merged lib we are loading, but we don't have a way to identify the JNI entry point which triggered the load.

There are many cases (like the one described above) where we see a library getting loaded, but can't reproduce locally.
If we log the short name in addition to so name, debugging these issues will become trivial.

Reviewed By: adicatana

Differential Revision: D53679442

fbshipit-source-id: fa92e00d7139def5e33b7707c2b0626c1bef7ead

java/com/facebook/soloader/SoLoader.java

@@ -986,7 +986,7 @@ private static boolean loadLibraryBySoNameImpl(
           if (!loaded) {
             try {
               LogUtil.d(TAG, "About to load: " + soName);
-              doLoadLibraryBySoName(soName, loadFlags, oldPolicy);
+              doLoadLibraryBySoName(soName, shortName, loadFlags, oldPolicy);
             } catch (UnsatisfiedLinkError ex) {
               String message = ex.getMessage();
               if (message != null && message.contains("unexpected e_machine:")) {
@@ -1074,7 +1074,10 @@ public static File unpackLibraryAndDependencies(String shortName) throws Unsatis
   }
 
   private static void doLoadLibraryBySoName(
-      String soName, int loadFlags, @Nullable StrictMode.ThreadPolicy oldPolicy)
+      String soName,
+      @Nullable String shortName,
+      int loadFlags,
+      @Nullable StrictMode.ThreadPolicy oldPolicy)
       throws UnsatisfiedLinkError {
     sSoSourcesLock.readLock().lock();
     try {
@@ -1096,6 +1099,9 @@ private static void doLoadLibraryBySoName(
     }
 
     if (SYSTRACE_LIBRARY_LOADING) {
+      if (shortName != null) {
+        Api18TraceUtils.beginTraceSection("SoLoader.loadLibrary[", shortName, "]");
+      }
       Api18TraceUtils.beginTraceSection("SoLoader.loadLibrary[", soName, "]");
     }
 
@@ -1120,6 +1126,9 @@ private static void doLoadLibraryBySoName(
       }
     } finally {
       if (SYSTRACE_LIBRARY_LOADING) {
+        if (shortName != null) {
+          Api18TraceUtils.endSection();
+        }
         Api18TraceUtils.endSection();
       }