From a6596c9925bdb7fead7ed31520bee7d05728c74d Mon Sep 17 00:00:00 2001
From: Josh Gao <jmgao@google.com>
Date: Wed, 17 Mar 2021 09:20:01 -0700
Subject: [PATCH] fdtrack: add stats logging.

Bug: http://b/183008833
Bug: http://b/183018597
Test: adb shell 'setprop persist.sys.debug.fdtrack_interval 10; stop; start' && statsd_testdrive 352
Change-Id: Ibc2293f8f1c7f0f29a166ac8dc93afc8dfd8b7de
Merged-In: Ibc2293f8f1c7f0f29a166ac8dc93afc8dfd8b7de
(cherry picked from commit 53731ea9ab0c131fb51e891946a17895571973d1)
---
 .../java/com/android/server/SystemServer.java | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/services/java/com/android/server/SystemServer.java b/services/java/com/android/server/SystemServer.java
index 7e718e52b7a04..ad89e96c74383 100644
--- a/services/java/com/android/server/SystemServer.java
+++ b/services/java/com/android/server/SystemServer.java
@@ -546,6 +546,8 @@ public final class SystemServer implements Dumpable {
 
         new Thread(() -> {
             boolean enabled = false;
+            long nextWrite = 0;
+
             while (true) {
                 int maxFd = getMaxFd();
                 if (maxFd > enableThreshold) {
@@ -556,12 +558,30 @@ public final class SystemServer implements Dumpable {
 
                 if (maxFd > enableThreshold && !enabled) {
                     Slog.i("System", "fdtrack enable threshold reached, enabling");
+                    FrameworkStatsLog.write(FrameworkStatsLog.FDTRACK_EVENT_OCCURRED,
+                            FrameworkStatsLog.FDTRACK_EVENT_OCCURRED__EVENT__ENABLED,
+                            maxFd);
+
                     System.loadLibrary("fdtrack");
                     enabled = true;
                 } else if (maxFd > abortThreshold) {
                     Slog.i("System", "fdtrack abort threshold reached, dumping and aborting");
+                    FrameworkStatsLog.write(FrameworkStatsLog.FDTRACK_EVENT_OCCURRED,
+                            FrameworkStatsLog.FDTRACK_EVENT_OCCURRED__EVENT__ABORTING,
+                            maxFd);
+
                     dumpHprof();
                     fdtrackAbort();
+                } else {
+                    // Limit this to once per hour.
+                    long now = SystemClock.elapsedRealtime();
+                    if (now > nextWrite) {
+                        nextWrite = now + 60 * 60 * 1000;
+                        FrameworkStatsLog.write(FrameworkStatsLog.FDTRACK_EVENT_OCCURRED,
+                                enabled ? FrameworkStatsLog.FDTRACK_EVENT_OCCURRED__EVENT__ENABLED
+                                        : FrameworkStatsLog.FDTRACK_EVENT_OCCURRED__EVENT__DISABLED,
+                                maxFd);
+                    }
                 }
 
                 try {