commit 07d6617b1bf0357876f7a3a3600494cc02ef07e7
author Dmitriy Filchenko <dmitriyf@google.com> Mon Jun 05 18:28:09 2023 +0000
committer Copybara-Service <copybara-worker@google.com> Mon Jun 05 11:30:32 2023 -0700
tree 150ac1db58d7bf0afd5e09f816617356a44a3baf
parent 65a9245b62050ec9e53d6cd8826b43988840caa2

[scudo] Change configuration for Trusty, use mmap()

Trusty runs in memory constrained environments, with many apps
having only one page (4KB) of heap memory available. However, we
still want to mmap() multiples of PAGE_SIZE at a time.

Additionally, switch Scudo from using sbrk() to mmap().

Reviewed By: cferris

Differential Revision: https://reviews.llvm.org/D151968

GitOrigin-RevId: 94407e1bba9807193afde61c56b6125c0fc0b1d1

size_class_map.h

diff --git a/size_class_map.h b/size_class_map.h
index 7665624..2a6e298 100644
--- a/size_class_map.h
+++ b/size_class_map.h
@@ -311,13 +311,11 @@
 
 typedef FixedSizeClassMap<SvelteSizeClassConfig> SvelteSizeClassMap;
 
-// Trusty is configured to only have one region containing blocks of size
-// 2^7 bytes.
 struct TrustySizeClassConfig {
   static const uptr NumBits = 1;
-  static const uptr MinSizeLog = 7;
-  static const uptr MidSizeLog = 7;
-  static const uptr MaxSizeLog = 7;
+  static const uptr MinSizeLog = 5;
+  static const uptr MidSizeLog = 5;
+  static const uptr MaxSizeLog = 15;
   static const u16 MaxNumCachedHint = 12;
   static const uptr MaxBytesCachedLog = 10;
   static const uptr SizeDelta = 0;