| =========================== |
| Boot time memory management |
| =========================== |
| |
| Early system initialization cannot use "normal" memory management |
| simply because it is not set up yet. But there is still need to |
| allocate memory for various data structures, for instance for the |
| physical page allocator. |
| |
| A specialized allocator called ``memblock`` performs the |
| boot time memory management. The architecture specific initialization |
| must set it up in :c:func:`setup_arch` and tear it down in |
| :c:func:`mem_init` functions. |
| |
| Once the early memory management is available it offers a variety of |
| functions and macros for memory allocations. The allocation request |
| may be directed to the first (and probably the only) node or to a |
| particular node in a NUMA system. There are API variants that panic |
| when an allocation fails and those that don't. |
| |
| Memblock also offers a variety of APIs that control its own behaviour. |
| |
| Memblock Overview |
| ================= |
| |
| .. kernel-doc:: mm/memblock.c |
| :doc: memblock overview |
| |
| |
| Functions and structures |
| ======================== |
| |
| Here is the description of memblock data structures, functions and |
| macros. Some of them are actually internal, but since they are |
| documented it would be silly to omit them. Besides, reading the |
| descriptions for the internal functions can help to understand what |
| really happens under the hood. |
| |
| .. kernel-doc:: include/linux/memblock.h |
| .. kernel-doc:: mm/memblock.c |
| :functions: |
