yet more atomics & cache-line fixes on work-stealing queue

JuliaLang · Feb 22, 2024 · cfa3be2 · cfa3be2
1 parent 8425b0e
commit cfa3be2
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/src/work-stealing-queue.h b/src/work-stealing-queue.h
@@ -3,6 +3,8 @@
 #ifndef WORK_STEALING_QUEUE_H
 #define WORK_STEALING_QUEUE_H
 
+#include <stdalign.h>
+
 #include "julia_atomics.h"
 #include "assert.h"
 
@@ -35,10 +37,10 @@ static inline ws_array_t *create_ws_array(size_t capacity, int32_t eltsz) JL_NOT
 }
 
 typedef struct {
-    _Atomic(int64_t) top;
-    char _padding[JL_CACHE_BYTE_ALIGNMENT - sizeof(_Atomic(int64_t))];
-    _Atomic(int64_t) bottom; // put on a separate cache line. conservatively estimate cache line size as 128 bytes
-    _Atomic(ws_array_t *) array;
+    // align to JL_CACHE_BYTE_ALIGNMENT
+    alignas(JL_CACHE_BYTE_ALIGNMENT) _Atomic(int64_t) top;
+    alignas(JL_CACHE_BYTE_ALIGNMENT) _Atomic(int64_t) bottom;
+    alignas(JL_CACHE_BYTE_ALIGNMENT) _Atomic(ws_array_t *) array;
 } ws_queue_t;
 
 static inline ws_array_t *ws_queue_push(ws_queue_t *q, void *elt, int32_t eltsz) JL_NOTSAFEPOINT