[compiler-rt] 0f1a92b - [scudo] Deallocate the AllocatorRingBuffer too in unmapTestOnly

[Caslyn Tonelli via llvm-commits]

Author: Fabio D'Urso
Date: 2023-05-16T20:09:08Z
New Revision: 0f1a92ba308a20dd4c790843191e3b642e90a9f3

URL: https://github.com/llvm/llvm-project/commit/0f1a92ba308a20dd4c790843191e3b642e90a9f3
DIFF: https://github.com/llvm/llvm-project/commit/0f1a92ba308a20dd4c790843191e3b642e90a9f3.diff

LOG: [scudo] Deallocate the AllocatorRingBuffer too in unmapTestOnly

The AllocatorRingBuffer is allocated dynamically when Allocator is
initialized. This patch adds a corresponding deinitialization call in
unmapTestOnly, to avoid running out of virtual memory if the tests are run
a large number of times on memory-constrained platforms.

Reviewed By: Chia-hungDuan

Differential Revision: https://reviews.llvm.org/D149266

Added: 
    

Modified: 
    compiler-rt/lib/scudo/standalone/combined.h

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/scudo/standalone/combined.h b/compiler-rt/lib/scudo/standalone/combined.h
index 006605659bfd9..52e2674400fb7 100644
--- a/compiler-rt/lib/scudo/standalone/combined.h
+++ b/compiler-rt/lib/scudo/standalone/combined.h
@@ -178,7 +178,7 @@ class Allocator {
         static_cast<uptr>(getFlags()->quarantine_size_kb << 10),
         static_cast<uptr>(getFlags()->thread_local_quarantine_size_kb << 10));
 
-    initRingBuffer();
+    mapAndInitializeRingBuffer();
   }
 
   // Initialize the embedded GWP-ASan instance. Requires the main allocator to
@@ -228,6 +228,7 @@ class Allocator {
   }
 
   void unmapTestOnly() {
+    unmapRingBuffer();
     TSDRegistry.unmapTestOnly(this);
     Primary.unmapTestOnly();
     Secondary.unmapTestOnly();
@@ -1508,17 +1509,16 @@ class Allocator {
         &RawRingBuffer[sizeof(AllocationRingBuffer)])[N];
   }
 
-  void initRingBuffer() {
+  void mapAndInitializeRingBuffer() {
     u32 AllocationRingBufferSize =
         static_cast<u32>(getFlags()->allocation_ring_buffer_size);
     if (AllocationRingBufferSize < 1)
       return;
-    MapPlatformData Data = {};
     RawRingBuffer = static_cast<char *>(
         map(/*Addr=*/nullptr,
             roundUp(ringBufferSizeInBytes(AllocationRingBufferSize),
                     getPageSizeCached()),
-            "AllocatorRingBuffer", /*Flags=*/0, &Data));
+            "AllocatorRingBuffer"));
     auto *RingBuffer = reinterpret_cast<AllocationRingBuffer *>(RawRingBuffer);
     RingBuffer->Size = AllocationRingBufferSize;
     static_assert(sizeof(AllocationRingBuffer) %
@@ -1527,6 +1527,11 @@ class Allocator {
                   "invalid alignment");
   }
 
+  void unmapRingBuffer() {
+    unmap(RawRingBuffer, roundUp(getRingBufferSize(), getPageSizeCached()));
+    RawRingBuffer = nullptr;
+  }
+
   static constexpr size_t ringBufferSizeInBytes(u32 AllocationRingBufferSize) {
     return sizeof(AllocationRingBuffer) +
            AllocationRingBufferSize *