commit 5a261a940a9ca6ae2413b3fc2ead25376ae2bf14
author Suren Baghdasaryan <surenb@google.com> Tue Oct 01 10:03:54 2019 -0700
committer android-build-merger <android-build-merger@google.com> Tue Oct 01 10:03:54 2019 -0700
tree dac5b85eac81d43fce7ad914f0e7bc7497026210
parent e51d7cf2c2abba9015bc9f1e28092c6032d8f1e5
parent 8a5742034c9e8e145f1fd2fd5c6a96553c9f87b4

Merge changes from topic "default_psi_kill_mode" am: c67350bc68 am: 8c1d025db4 am: c8ad8b4a0e
am: 0dfa191e7b

Change-Id: I623717567222a48276162a0ffcfad0ed77c973ae

lmkd/lmkd.c

diff --git a/lmkd/lmkd.c b/lmkd/lmkd.c
index b9a7366..2ba3f44 100644
--- a/lmkd/lmkd.c
+++ b/lmkd/lmkd.c
@@ -83,6 +83,8 @@
 #define PROC_STATUS_TGID_FIELD "Tgid:"
 #define LINE_MAX 128
 
+#define PERCEPTIBLE_APP_ADJ 200
+
 /* Android Logger event logtags (see event.logtags) */
 #define MEMINFO_LOG_TAG 10195355
 
@@ -2046,6 +2048,8 @@
     enum reclaim_state reclaim = NO_RECLAIM;
     enum zone_watermark wmark = WMARK_NONE;
     char kill_desc[LINE_MAX];
+    bool cut_thrashing_limit = false;
+    int min_score_adj = 0;
 
     /* Skip while still killing a process */
     if (is_kill_pending()) {
@@ -2164,22 +2168,35 @@
             mi.field.free_swap * page_k, swap_low_threshold * page_k);
     } else if (wmark < WMARK_HIGH && thrashing > thrashing_limit) {
         /* Page cache is thrashing while memory is low */
-        thrashing_limit = (thrashing_limit * (100 - thrashing_limit_decay_pct)) / 100;
         kill_reason = LOW_MEM_AND_THRASHING;
         snprintf(kill_desc, sizeof(kill_desc), "%s watermark is breached and thrashing (%"
             PRId64 "%%)", wmark > WMARK_LOW ? "min" : "low", thrashing);
+        cut_thrashing_limit = true;
+        /* Do not kill perceptible apps because of thrashing */
+        min_score_adj = PERCEPTIBLE_APP_ADJ;
     } else if (reclaim == DIRECT_RECLAIM && thrashing > thrashing_limit) {
         /* Page cache is thrashing while in direct reclaim (mostly happens on lowram devices) */
-        thrashing_limit = (thrashing_limit * (100 - thrashing_limit_decay_pct)) / 100;
         kill_reason = DIRECT_RECL_AND_THRASHING;
         snprintf(kill_desc, sizeof(kill_desc), "device is in direct reclaim and thrashing (%"
             PRId64 "%%)", thrashing);
+        cut_thrashing_limit = true;
+        /* Do not kill perceptible apps because of thrashing */
+        min_score_adj = PERCEPTIBLE_APP_ADJ;
     }
 
     /* Kill a process if necessary */
     if (kill_reason != NONE) {
-        int pages_freed = find_and_kill_process(0, kill_desc);
-        killing = (pages_freed > 0);
+        int pages_freed = find_and_kill_process(min_score_adj, kill_desc);
+        if (pages_freed > 0) {
+            killing = true;
+            if (cut_thrashing_limit) {
+                /*
+                 * Cut thrasing limit by thrashing_limit_decay_pct percentage of the current
+                 * thrashing limit until the system stops thrashing.
+                 */
+                thrashing_limit = (thrashing_limit * (100 - thrashing_limit_decay_pct)) / 100;
+            }
+        }
         meminfo_log(&mi);
     }