Some comments

src/arena.h

@@ -14,18 +14,19 @@ struct ArenaParams {
 typedef struct MemoryBlock MemoryBlock;
 struct MemoryBlock {
     U8 *base;
-    U32 size;
-    U32 pos;          // start of next allocation
-    U32 base_pos;     // absolute position of base relative to the first linked arena
-    U32 committed_pos;
+    U32 size;           // Block size, page aligned
+    U32 pos;            // start of next allocation
+    U32 base_pos;       // absolute position of base relative to the first linked arena
+    U32 committed_pos;  // end of committed region. Will be page aligned
     MemoryBlock *prev;
 };
 
 typedef struct Arena Arena;
 struct Arena {
     MemoryBlock *current;
-    U32 block_size;
-    U32 commit_size;
+    U32 block_size;     // requested block size
+    U32 commit_size;    // requested commit size
+    U32 page_size;      // cached page size
     ArenaFlags flags;
     S32 checkpoint_level;
 };
@@ -39,10 +40,7 @@ struct ArenaCheckPoint {
 StaticAssert(sizeof(MemoryBlock) <= 64);
 #define MemoryBlock_Header_Size 64u
 
-
-
 void arena_init(Arena *arena, const ArenaParams *params);
-
 void arena_free(Arena *arena);
 void *arena_push(Arena *arena, U32 size, U32 align);