From 1ab88b30379f20d6f583568e09e21248ca44db4d Mon Sep 17 00:00:00 2001
From: Carlos Galo <carlosgalo@google.com>
Date: Thu, 5 Oct 2023 21:15:57 +0000
Subject: ActivityManagerService: oom atom logging

Logging kernel out-of-memory (OOM) kills in statsd.

Bug: 244232958
Test: statsd_testdrive 754 to inspect statsd logged atoms data
Change-Id: Ibed9c431d4708be9c5eb2f79c79d7e6be1a5dcf9
Signed-off-by: Carlos Galo <carlosgalo@google.com>
---
 core/java/android/os/OomKillRecord.java               | 19 ++++++++++++++++++-
 .../core/java/com/android/server/am/ProcessList.java  |  2 ++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/core/java/android/os/OomKillRecord.java b/core/java/android/os/OomKillRecord.java
index 151a65fdfaf5..ca1d49a93def 100644
--- a/core/java/android/os/OomKillRecord.java
+++ b/core/java/android/os/OomKillRecord.java
@@ -15,10 +15,15 @@
  */
 package android.os;
 
+import com.android.internal.util.FrameworkStatsLog;
 
 /**
+ * Activity manager communication with kernel out-of-memory (OOM) data handling
+ * and statsd atom logging.
+ *
  * Expected data to get back from the OOM event's file.
- * Note that this should be equivalent to the struct <b>OomKill</b> inside
+ * Note that this class fields' should be equivalent to the struct
+ * <b>OomKill</b> inside
  * <pre>
  * system/memory/libmeminfo/libmemevents/include/memevents.h
  * </pre>
@@ -41,6 +46,18 @@ public final class OomKillRecord {
         this.mOomScoreAdj = oomScoreAdj;
     }
 
+    /**
+     * Logs the event when the kernel OOM killer claims a victims to reduce
+     * memory pressure.
+     * KernelOomKillOccurred = 754
+     */
+    public void logKillOccurred() {
+        FrameworkStatsLog.write(
+                FrameworkStatsLog.KERNEL_OOM_KILL_OCCURRED,
+                mUid, mPid, mOomScoreAdj, mTimeStampInMillis,
+                mProcessName);
+    }
+
     public long getTimestampMilli() {
         return mTimeStampInMillis;
     }
diff --git a/services/core/java/com/android/server/am/ProcessList.java b/services/core/java/com/android/server/am/ProcessList.java
index 4572766371ec..c13a3dac76ec 100644
--- a/services/core/java/com/android/server/am/ProcessList.java
+++ b/services/core/java/com/android/server/am/ProcessList.java
@@ -869,6 +869,8 @@ public final class ProcessList {
                                 ApplicationExitInfo.REASON_LOW_MEMORY,
                                 ApplicationExitInfo.SUBREASON_OOM_KILL,
                                 "oom");
+
+                            oomKill.logKillOccurred();
                         }
                     }
                 }
-- 
cgit v1.2.3-59-g8ed1b