[compiler-rt] [NFC] Make RingBuffer an atomic pointer (PR #82547)

[via llvm-commits]

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@@ -688,14 +688,16 @@ class Allocator {
     Quarantine.disable();
     Primary.disable();
     Secondary.disable();
-    if (Depot)
-      Depot->disable();
+    AllocationRingBuffer *RB = getRingBuffer();
+    if (RB)
+      RB->disable();
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ChiaHungDuan wrote:

Ah, sorry my bad,

I want to say something like adding two functions, `DisableRingBuffer`/`EnableRingBuffer`

So that we don't lift the details of ring buffer to the user



https://github.com/llvm/llvm-project/pull/82547