commit 1afd6988928f22aeeb417e21b84a7fcd827e9186
author ChiaHungDuan <chiahungduan@google.com> Mon Oct 14 10:46:12 2024 -0700
committer Copybara-Service <copybara-worker@google.com> Mon Oct 14 10:48:06 2024 -0700
tree 10cfcdcec1c3edea0338b02ac5c023d1c2ef4812
parent 02411df172c6b33b2aa93d9fe1428baa947ca705

[scudo] Apply the min release threshold to the group (#112014)

For the block smaller than a page size, one block is unlikely to
introduce more unused pages (at most 2 if it acrosses the page boundary
and both touched pages are unused). So it's better to apply the
threshold to reduce the time of scanning groups that can't release any
new pages.

GitOrigin-RevId: 53c9553562c778338a82574123fb7cfb943c4042

primary64.h

diff --git a/primary64.h b/primary64.h
index 97188a5..1865ed4 100644
--- a/primary64.h
+++ b/primary64.h
@@ -1492,6 +1492,8 @@
       }
 
       const uptr PushedBytesDelta = BytesInBG - BG->BytesInBGAtLastCheckpoint;
+      if (PushedBytesDelta < getMinReleaseAttemptSize(BlockSize))
+        continue;
 
       // Given the randomness property, we try to release the pages only if the
       // bytes used by free blocks exceed certain proportion of group size. Note