[LibOS] Fix memmgr free list performance bug

The `CHECK_LIST_HEAD` macro in `common/include/list.h` is used in memmgr to traverse the free list and perform assertion checks. However, the loop is not removed by the compiler even in release mode, leading to unnecessary overhead. This commit fixes this by changing the macro to `(void)0` in release mode. Signed-off-by: Adrian Lutsch <[email protected]>
gramineproject · Nov 12, 2024 · 0997103 · 0997103
1 parent 87c752f
commit 0997103
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/common/include/list.h b/common/include/list.h
@@ -280,6 +280,7 @@
          (CURSOR) != (HEAD)->first && (HEAD)->first; (CURSOR) = (TMP), (TMP) = (TMP)->FIELD.next)
 
 /* Assertion code written in Gramine project */
+#ifdef DEBUG
 #define CHECK_LIST_HEAD(TYPE, HEAD, FIELD)                               \
     do {                                                                 \
         TYPE pos;                                                        \
@@ -290,6 +291,9 @@
             assert(pos->FIELD.next->FIELD.prev == pos);                  \
         }                                                                \
     } while (0)
+#else
+#define CHECK_LIST_HEAD(TYPE, HEAD, FIELD) ((void)0)
+#endif
 
 // Add NEW to OLD at position first (assuming first is all we need for now)
 // Can probably drop TYPE with some preprocessor smarts