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内存管理之内存初始化内存管理...
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在NUMA系统上, 基本的API是相同的, 但是函数增加了_node后缀, 与UMA系统的函数相比, 还需要一些额外的参数, 用于指定内存分配的结点.
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| 函数 | 定义 |
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|:---:|:---:|
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| alloc_bootmem(size) | 按照指定大小在ZONE_NORMAL内存域分配函数. 数据是对齐的, 这使得内存或者从可适用于L1高速缓存的理想位置开始| [alloc_bootmem](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L122)<br>[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L700)<br>[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?=4.7#L672) |
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| alloc_bootmem_align(x, align) | 同alloc_bootmem函数, 按照指定大小在ZONE_NORMAL内存域分配函数, 并按照align进行数据对齐 | [alloc_bootmem_align](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L124)<br>基于__alloc_bootmem实现 |
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| alloc_bootmem_pages(size)) | 同alloc_bootmem函数, 按照指定大小在ZONE_NORMAL内存域分配函数, 其中_page只是指定数据的对其方式从页边界(__pages)开始 | [alloc_bootmem_pages](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L128)<br>基于__alloc_bootmem实现 |
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| alloc_bootmem_nopanic(size) | alloc_bootmem_nopanic是最基础的通用的，一个用来尽力而为分配内存的函数，它通过list_for_each_entry在全局链表bdata_list中分配内存. alloc_bootmem和alloc_bootmem_nopanic类似，它的底层实现首先通过alloc_bootmem_nopanic函数分配内存，但是一旦内存分配失败，系统将通过panic("Out of memory")抛出信息，并停止运行 | [alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L126)<br>[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) |
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| alloc_bootmem_low(size) | 按照指定大小在ZONE_DMA内存域分配函数. 类似于alloc_bootmem, 数据是对齐的 | [alloc_bootmem_low_pages_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L141)<br>底层基于___alloc_bootmem |
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| alloc_bootmem_low_pages_nopanic(size) | 按照指定大小在ZONE_DMA内存域分配函数. 类似于alloc_bootmem_pages, 数据在页边界对齐, 并且错误后不输出panic | [alloc_bootmem_low_pages_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L143)<br>底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L838)
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| alloc_bootmem_low_pages(size) | 按照指定大小在ZONE_DMA内存域分配函数. 类似于alloc_bootmem_pages, 数据在页边界对齐 | [alloc_bootmem_low_pages](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L832)<br>底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L838) |
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| alloc_bootmem_node(pgdat, size) | [alloc_bootmem_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L132)<br>[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L777)<br>[ ___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708)|
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| alloc_bootmem_node_nopanic(pgdat, size) | [alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L134)<br>[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L738)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) |
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| alloc_bootmem_pages_node(pgdat, size) | [alloc_bootmem_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L136)<br>[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) |
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| alloc_bootmem_pages_node_nopanic(pgdat, size) | [alloc_bootmem_pages_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L138)<br>[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L738)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) |
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| alloc_bootmem_low_pages_node(pgdat, size) | [alloc_bootmem_low_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L14)<br>[__alloc_bootmem_low_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L861)<be>[___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L707) |
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@@ -341,7 +341,7 @@ bootmem提供了各种函数用于在初始化期间分配内存.
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| alloc_bootmem(size) | 按照指定大小在ZONE_NORMAL内存域分配函数. 数据是对齐的, 这使得内存或者从可适用于L1高速缓存的理想位置开始| [alloc_bootmem](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L122)<br>[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L700)<br>[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?=4.7#L672) |
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| alloc_bootmem_align(x, align) | 同alloc_bootmem函数, 按照指定大小在ZONE_NORMAL内存域分配函数, 并按照align进行数据对齐 | [alloc_bootmem_align](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L124)<br>基于__alloc_bootmem实现 |
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| alloc_bootmem_pages(size)) | 同alloc_bootmem函数, 按照指定大小在ZONE_NORMAL内存域分配函数, 其中_page只是指定数据的对其方式从页边界(__pages)开始 | [alloc_bootmem_pages](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L128)<br>基于__alloc_bootmem实现 |
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| alloc_bootmem_nopanic(size) | alloc_bootmem_nopanic是最基础的通用的，一个用来尽力而为分配内存的函数，它通过list_for_each_entry在全局链表bdata_list中分配内存. alloc_bootmem和alloc_bootmem_nopanic类似，它的底层实现首先通过alloc_bootmem_nopanic函数分配内存，但是一旦内存分配失败，系统将通过panic("Out of memory")抛出信息，并停止运行 | [alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L126)<br>[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632)
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| alloc_bootmem_nopanic(size) | alloc_bootmem_nopanic是最基础的通用的，一个用来尽力而为分配内存的函数，它通过list_for_each_entry在全局链表bdata_list中分配内存. alloc_bootmem和alloc_bootmem_nopanic类似，它的底层实现首先通过alloc_bootmem_nopanic函数分配内存，但是一旦内存分配失败，系统将通过panic("Out of memory")抛出信息，并停止运行 | [alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L126)<br>[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) |
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+71
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@@ -1,4 +1,4 @@
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启动过程期间的内存管理--bootmem分配器
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启动过程期间的内存管理--memblock分配器
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=======
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@@ -267,12 +267,12 @@ enum {
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| memblock | | |
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| _______________________ | | |
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| | memory | | | Array of the |
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| | memblock_type |-|-->| membock_region |
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| | memblock_type |-|-->| membock_region |
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| |_______________________| | | |
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| | +---------------------------+
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| _______________________ | +---------------------------+
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| | reserved | | | |
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| | memblock_type |-|-->| Array of the |
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| | memblock_type |-|-->| Array of the |
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| |_______________________| | | memblock_region |
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| | | |
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+---------------------------+ +---------------------------+
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@@ -472,7 +472,7 @@ memblock_add_range函数添加新的内存区域到内存块中, 定义在[mm/me
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* 首先，该函数检查给定的内存区域大小, 如果是0就返回.
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* 首先，该函数检查给定的内存区域大小, 如果是0就返回.
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* 在这之后, memblock_add_range用给定的memblock_type检查memblock结构体中是否存在内存区域
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@@ -504,9 +504,7 @@ int __init_memblock memblock_add_range(struct memblock_type *type,
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bool insert = false;
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phys_addr_t obase = base;
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／* 获取内存区域的结束位置,
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* memblock_cap_size函数会设置size大小确保base + size不会溢出
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*/
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* memblock_cap_size函数会设置size大小确保base + size不会溢出 */
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phys_addr_t end = base + memblock_cap_size(base, &size);
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int idx, nr_new;
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struct memblock_region *rgn;
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@@ -1019,6 +1017,70 @@ int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
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return memblock_remove_range(&memblock.reserved, base, size);
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}
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```
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#3 兼容bootmem的接口API
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-------
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我们了解到memblock是作为bootmem的替代品而引入内核的
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在编译Kernel的时候可以选择nobootmem或者bootmem 来在buddy system起来之前管理memory.
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这两种机制对提供的API是一致的，因此对用户是透明的
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参见[mm/Makefile](http://lxr.free-electrons.com/source/mm/Makefile#L44)
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```cpp
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ifdef CONFIG_NO_BOOTMEM
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obj-y += nobootmem.o
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else
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obj-y += bootmem.o
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endif
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```
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为了保证系统的兼容性, 内核为bootmem和memblock提供了相同的API接口.
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由于接口是一致的, 那么他们共同使用一份
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| 头文件 | bootmem接口 | nobootmem接口 |
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|:-------:|:----------------:|:-------------------:|
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| [include/linux/bootmem.h](http://lxr.free-electrons.com/source/include/linux/bootmem.h) | [mm/bootmem.c](http://lxr.free-electrons.com/source/mm/bootmem.c) | [mm/nobootmem.c](http://lxr.free-electrons.com/source/mm/nobootmem.c) |
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<br>
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我们知道memblock自己的接口都在自己的头文件和源文件中
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| memblock 头文件 | memblock接口 |
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|:--------------:|:------------:|
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| [include/linux/memblock.h](http://lxr.free-electrons.com/source/include/linux/memblock.h?v=4.7) | [mm/memblock.c](http://lxr.free-electrons.com/source/mm/memblock.c?v=4.7)
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为了实现接口兼容, 内核用[mm/memblock.c](http://lxr.free-electrons.com/source/mm/memblock.c?v=4.7)定义的memblock接口, 实现了一套bootmem的接口机制, 而bootmem的接口我们在上一篇引导内存管理bootmem机制中已经讲过了, 这些实现的bootmem函数接口API, 就定义在[mm/nobootmem.c](http://lxr.free-electrons.com/source/mm/nobootmem.c)文件中, 然后内核把他们进行了封装, 然后提供了与bootmem相同功能和函数的接口, 这些接口都在[include/linux/memblock.h](http://lxr.free-electrons.com/source/include/linux/memblock.h?v=4.7).
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在NUMA系统上, 基本的API是相同的, 但是函数增加了_node后缀, 与UMA系统的函数相比, 还需要一些额外的参数, 用于指定内存分配的结点.
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| 函数 | bootmem定义 | nobootmem定义 |
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|:-----:|:------------------:|:----------------------:|
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| ZONE_NORMAL的分配函数 | 按照指定大小在ZONE_NORMAL内存域分配函数. 数据是对齐的, 这使得内存或者从可适用于L1高速缓存的理想位置开始| |
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| alloc_bootmem(size) | [alloc_bootmem](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L122)<br>[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L700)<br>[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?=4.7#L672) | [alloc_bootmem](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L122)<br>[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L309)<br>[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L281) |
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| alloc_bootmem_align(size) | [alloc_bootmem_align](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L124)<br>基于__alloc_bootmem实现 | [alloc_bootmem_align](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L124)<br>[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L309)<br>[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L281) |
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| alloc_bootmem_pages(size)) | [alloc_bootmem_pages](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L128)<br>基于__alloc_bootmem实现 | [alloc_bootmem_pages](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L128)<br>基于__alloc_bootmem实现 |
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| alloc_bootmem_nopanic(size) | [alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L126)<br>[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) | [alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L126)<br>[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L261)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L235) |
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| ZONE_DMA区域的分配函数 | |
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| alloc_bootmem_low(size) | [alloc_bootmem_low](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L141)<br>[__alloc_bootmem_low](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L415)底层基于___alloc_bootmem | [alloc_bootmem_low](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L141)<br>底层基于___alloc_bootmem |
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| alloc_bootmem_low_pages_nopanic(size) | [alloc_bootmem_low_pages_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L143)<br>底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L838)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) | [alloc_bootmem_low_pages_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L143)<br>底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L421)<br>[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L235) |
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| alloc_bootmem_low_pages(size) | [alloc_bootmem_low_pages](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L832)<br>底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L838) | [alloc_bootmem_low_pages](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L832)<br>底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L421) |
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| NUMA结构的分配函数 | | |
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| alloc_bootmem_node(pgdat, size) | [alloc_bootmem_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L132)<br>[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L777)<br>[ ___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) | [alloc_bootmem_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L132)<br>[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L383)<br>[ ___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) |
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| alloc_bootmem_node_nopanic(pgdat, size) | [alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L134)<br>[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L738)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) | [alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L134)<br>[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L344)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) |
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| alloc_bootmem_pages_node(pgdat, size) | [alloc_bootmem_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L136)<br>[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) | [alloc_bootmem_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L136)<br>[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L344)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) |
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| alloc_bootmem_pages_node_nopanic(pgdat, size) | [alloc_bootmem_pages_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L138)<br>[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L344)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) |
|
||||
| alloc_bootmem_low_pages_node(pgdat, size) | [alloc_bootmem_low_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L14)<br>[__alloc_bootmem_low_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L861)<be>[___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L707) | [alloc_bootmem_low_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L14)<br>[__alloc_bootmem_low_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L444)<be>[___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L353)<br>[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) |
|
||||
|
||||
|
||||
我们可以看到最基本的
|
||||
|
||||
|
||||
#3 memblock初始化
|
||||
@@ -1111,6 +1173,8 @@ void __init memblock_x86_fill(void)
|
||||
|
||||
至此, 我们的memblock就初始化好了, 简单而且粗暴
|
||||
|
||||
|
||||
|
||||
##3.2 arm架构下的memblock初始化
|
||||
-------
|
||||
|
||||
@@ -1,12 +0,0 @@
|
||||
```cpp
|
||||
/*
|
||||
* If this was the first round, resize array and repeat for actual
|
||||
* insertions; otherwise, merge and return.
|
||||
*/
|
||||
if (!insert) {
|
||||
/* ...... */
|
||||
} else {
|
||||
memblock_merge_regions(type);
|
||||
return 0;
|
||||
}
|
||||
```
|
||||
Reference in new issue
Block a user