change system file

hc

2024-10-09 244b2c5ca8b14627e4a17755e5922221e121c771

 kernel/Documentation/core-api/boot-time-mm.rst
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@@ -5,54 +5,23 @@
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 Early system initialization cannot use "normal" memory management
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 simply because it is not set up yet. But there is still need to
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 allocate memory for various data structures, for instance for the
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-physical page allocator. To address this, a specialized allocator
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-called the :ref:`Boot Memory Allocator <bootmem>`, or bootmem, was
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-introduced. Several years later PowerPC developers added a "Logical
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-Memory Blocks" allocator, which was later adopted by other
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-architectures and renamed to :ref:`memblock <memblock>`. There is also
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-a compatibility layer called `nobootmem` that translates bootmem
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-allocation interfaces to memblock calls.
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+physical page allocator.
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-The selection of the early allocator is done using
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-``CONFIG_NO_BOOTMEM`` and ``CONFIG_HAVE_MEMBLOCK`` kernel
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-configuration options. These options are enabled or disabled
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-statically by the architectures' Kconfig files.
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-
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-* Architectures that rely only on bootmem select
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-  ``CONFIG_NO_BOOTMEM=n && CONFIG_HAVE_MEMBLOCK=n``.
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-* The users of memblock with the nobootmem compatibility layer set
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-  ``CONFIG_NO_BOOTMEM=y && CONFIG_HAVE_MEMBLOCK=y``.
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-* And for those that use both memblock and bootmem the configuration
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-  includes ``CONFIG_NO_BOOTMEM=n && CONFIG_HAVE_MEMBLOCK=y``.
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-
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-Whichever allocator is used, it is the responsibility of the
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-architecture specific initialization to set it up in
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-:c:func:`setup_arch` and tear it down in :c:func:`mem_init` functions.
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+A specialized allocator called ``memblock`` performs the
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+boot time memory management. The architecture specific initialization
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+must set it up in :c:func:`setup_arch` and tear it down in
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+:c:func:`mem_init` functions.
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 Once the early memory management is available it offers a variety of
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 functions and macros for memory allocations. The allocation request
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 may be directed to the first (and probably the only) node or to a
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 particular node in a NUMA system. There are API variants that panic
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-when an allocation fails and those that don't. And more recent and
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-advanced memblock even allows controlling its own behaviour.
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+when an allocation fails and those that don't.
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-.. _bootmem:
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+Memblock also offers a variety of APIs that control its own behaviour.
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-Bootmem
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-=======
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-
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-(mostly stolen from Mel Gorman's "Understanding the Linux Virtual
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-Memory Manager" `book`_)
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-
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-.. _book: https://www.kernel.org/doc/gorman/
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-
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-.. kernel-doc:: mm/bootmem.c
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-   :doc: bootmem overview
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-
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-.. _memblock:
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-
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-Memblock
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-========
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+Memblock Overview
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+=================
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 .. kernel-doc:: mm/memblock.c
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    :doc: memblock overview
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@@ -60,26 +29,6 @@
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 Functions and structures
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 ========================
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-
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-Common API
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-----------
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-
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-The functions that are described in this section are available
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-regardless of what early memory manager is enabled.
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-
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-.. kernel-doc:: mm/nobootmem.c
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-
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-Bootmem specific API
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---------------------
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-
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-These interfaces available only with bootmem, i.e when ``CONFIG_NO_BOOTMEM=n``
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-
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-.. kernel-doc:: include/linux/bootmem.h
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-.. kernel-doc:: mm/bootmem.c
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-   :nodocs:
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-
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-Memblock specific API
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----------------------
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 Here is the description of memblock data structures, functions and
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 macros. Some of them are actually internal, but since they are
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 .. kernel-doc:: include/linux/memblock.h
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 .. kernel-doc:: mm/memblock.c
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-   :nodocs:
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+   :functions: