[MemInit] Remove old API, introduce new MemInit API.
Introduces new heap-zero-init API. We've realised that it's better to be
able to individually control MTE and heap zero-init. Having
heap-zero-init not be controllable without affecting MTE affects our
ability to turn off heap-zero-init in zygote-forked applications.
Bug: 135772972
Test: On FVP: atest -s localhost:5555 malloc#zero_init \
Test: malloc#disable_mte heap_tagging_level
Change-Id: I8c6722502733259934c699f4f1269eaf1641a09f
diff --git a/libc/include/malloc.h b/libc/include/malloc.h
index 598a50b..bae1f68 100644
--- a/libc/include/malloc.h
+++ b/libc/include/malloc.h
@@ -204,18 +204,19 @@
#define M_TSDS_COUNT_MAX (-202)
/**
- * mallopt() option to disable heap initialization across the whole process.
- * If the hardware supports memory tagging, this also disables memory tagging.
- * May be called at any time, including when multiple threads are running. The
- * value is unused but must be set to 0.
+ * mallopt() option to decide whether heap memory is zero-initialized on
+ * allocation across the whole process. May be called at any time, including
+ * when multiple threads are running. An argument of zero indicates memory
+ * should not be zero-initialized, any other value indicates to initialize heap
+ * memory to zero.
*
- * Note that these memory mitigations are only implemented in scudo and
- * therefore this will have no effect when using another allocator (such as
- * jemalloc on Android Go devices).
+ * Note that this memory mitigations is only implemented in scudo and therefore
+ * this will have no effect when using another allocator (such as jemalloc on
+ * Android Go devices).
*
* Available since API level 31.
*/
-#define M_BIONIC_DISABLE_MEMORY_MITIGATIONS (-203)
+#define M_BIONIC_ZERO_INIT (-203)
/**
* mallopt() option to change the heap tagging state. May be called at any