From 48ec09ca1036fa66e2a197987946dfdb04128ee9 Mon Sep 17 00:00:00 2001
From: d-netto <diogonetto.dcn@gmail.com>
Date: Sun, 21 Jan 2024 10:14:12 -0300
Subject: [PATCH] place work-stealing queue indices on different cache lines to
 avoid false-sharing

---
 src/work-stealing-queue.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/work-stealing-queue.h b/src/work-stealing-queue.h
index 38429e02886e9..070a42b98ef85 100644
--- a/src/work-stealing-queue.h
+++ b/src/work-stealing-queue.h
@@ -36,6 +36,13 @@ static inline ws_array_t *create_ws_array(size_t capacity, int32_t eltsz) JL_NOT
 
 typedef struct {
     _Atomic(int64_t) top;
+    // put `top` and `bottom` on different cache lines
+    // to avoid false sharing
+#ifdef _P64
+    void *_ignore[7];
+#else
+    void *_ignore[15];
+#endif
     _Atomic(int64_t) bottom;
     _Atomic(ws_array_t *) array;
 } ws_queue_t;