From 7f31cbcc5a97169e5a19ab29c080f87f78a31403 Mon Sep 17 00:00:00 2001 From: gatieme Date: Thu, 11 Aug 2016 00:29:12 +0800 Subject: [PATCH] =?UTF-8?q?=E5=86=85=E5=AD=98=E7=AE=A1=E7=90=86=E4=B9=8B?= =?UTF-8?q?=E5=86=85=E5=AD=98=E5=88=9D=E5=A7=8B=E5=8C=96=E5=86=85=E5=AD=98?= =?UTF-8?q?=E7=AE=A1=E7=90=86...?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- 1.c | 26 +++++++ .../03-initialize/02-bootmem/README.md | 2 +- .../{03-nobootmem => 03-memblock}/README.md | 78 +++++++++++++++++-- study/kernel/02-memory/03-initialize/1.c | 12 --- 4 files changed, 98 insertions(+), 20 deletions(-) create mode 100644 1.c rename study/kernel/02-memory/03-initialize/{03-nobootmem => 03-memblock}/README.md (82%) delete mode 100644 study/kernel/02-memory/03-initialize/1.c diff --git a/1.c b/1.c new file mode 100644 index 0000000..3e32bc3 --- /dev/null +++ b/1.c @@ -0,0 +1,26 @@ +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. + + +| 函数 | 定义 | +|:---:|:---:| + +| 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)
[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L700)
[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?=4.7#L672) | +| 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)
基于__alloc_bootmem实现 | +| 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)
基于__alloc_bootmem实现 | +| 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)
[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)
[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) | + +| 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)
底层基于___alloc_bootmem | +| 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)
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(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)
底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L838) | + + +| alloc_bootmem_node(pgdat, size) | [alloc_bootmem_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L132)
[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L777)
[ ___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708)| +| alloc_bootmem_node_nopanic(pgdat, size) | [alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L134)
[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L738)
[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) | +| alloc_bootmem_pages_node(pgdat, size) | [alloc_bootmem_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L136)
[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)
[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) | +| 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)
[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L738)
[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L708) | +| 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)
[__alloc_bootmem_low_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L861)[___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)
[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L707) | + + + + + \ No newline at end of file diff --git a/study/kernel/02-memory/03-initialize/02-bootmem/README.md b/study/kernel/02-memory/03-initialize/02-bootmem/README.md index 7a4ad13..42fa007 100644 --- a/study/kernel/02-memory/03-initialize/02-bootmem/README.md +++ b/study/kernel/02-memory/03-initialize/02-bootmem/README.md @@ -341,7 +341,7 @@ bootmem提供了各种函数用于在初始化期间分配内存. | 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)
[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L700)
[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?=4.7#L672) | | 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)
基于__alloc_bootmem实现 | | 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)
基于__alloc_bootmem实现 | -| 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)
[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)
[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) +| 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)
[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)
[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L632) | diff --git a/study/kernel/02-memory/03-initialize/03-nobootmem/README.md b/study/kernel/02-memory/03-initialize/03-memblock/README.md similarity index 82% rename from study/kernel/02-memory/03-initialize/03-nobootmem/README.md rename to study/kernel/02-memory/03-initialize/03-memblock/README.md index f64dc41..7de643e 100644 --- a/study/kernel/02-memory/03-initialize/03-nobootmem/README.md +++ b/study/kernel/02-memory/03-initialize/03-memblock/README.md @@ -1,4 +1,4 @@ -启动过程期间的内存管理--bootmem分配器 +启动过程期间的内存管理--memblock分配器 ======= @@ -267,12 +267,12 @@ enum { | memblock | | | | _______________________ | | | | | memory | | | Array of the | -| | memblock_type |-|-->| membock_region | +| | memblock_type |-|-->| membock_region | | |_______________________| | | | | | +---------------------------+ | _______________________ | +---------------------------+ | | reserved | | | | -| | memblock_type |-|-->| Array of the | +| | memblock_type |-|-->| Array of the | | |_______________________| | | memblock_region | | | | | +---------------------------+ +---------------------------+ @@ -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 -* 首先，该函数检查给定的内存区域大小, 如果是0就返回. +* 首先，该函数检查给定的内存区域大小, 如果是0就返回. * 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 @@ -504,9 +504,7 @@ int __init_memblock memblock_add_range(struct memblock_type *type, bool insert = false; phys_addr_t obase = base; ／* 获取内存区域的结束位置, - * memblock_cap_size函数会设置size大小确保base + size不会溢出 - - */ + * memblock_cap_size函数会设置size大小确保base + size不会溢出 */ phys_addr_t end = base + memblock_cap_size(base, &size); int idx, nr_new; struct memblock_region *rgn; @@ -1019,6 +1017,70 @@ int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size) return memblock_remove_range(&memblock.reserved, base, size); } ``` +#3 兼容bootmem的接口API +------- + +我们了解到memblock是作为bootmem的替代品而引入内核的 + +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. +这两种机制对提供的API是一致的，因此对用户是透明的 + +参见[mm/Makefile](http://lxr.free-electrons.com/source/mm/Makefile#L44) + + +```cpp +ifdef CONFIG_NO_BOOTMEM + obj-y += nobootmem.o +else + obj-y += bootmem.o +endif +``` + + +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. + + +由于接口是一致的, 那么他们共同使用一份 + +| 头文件 | bootmem接口 | nobootmem接口 | +|:-------:|:----------------:|:-------------------:| +| [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) | + +
+我们知道memblock自己的接口都在自己的头文件和源文件中 + +| memblock 头文件 | memblock接口 | +|:--------------:|:------------:| +| [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) + + +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). + + + +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. + + +| 函数 | bootmem定义 | nobootmem定义 | +|:-----:|:------------------:|:----------------------:| +| 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| | +| alloc_bootmem(size) | [alloc_bootmem](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L122)
[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L700)
[___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)
[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L309)
[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L281) | +| alloc_bootmem_align(size) | [alloc_bootmem_align](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L124)
基于__alloc_bootmem实现 | [alloc_bootmem_align](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L124)
[__alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L309)
[___alloc_bootmem](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L281) | +| alloc_bootmem_pages(size)) | [alloc_bootmem_pages](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L128)
基于__alloc_bootmem实现 | [alloc_bootmem_pages](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L128)
基于__alloc_bootmem实现 | +| alloc_bootmem_nopanic(size) | [alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L126)
[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L664)
[___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)
[__alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L261)
[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L235) | +| ZONE_DMA区域的分配函数 | | +| alloc_bootmem_low(size) | [alloc_bootmem_low](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L141)
[__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)
底层基于___alloc_bootmem | +| 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)
底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L838)
[___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)
底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L421)
[___alloc_bootmem_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L235) | +| alloc_bootmem_low_pages(size) | [alloc_bootmem_low_pages](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L832)
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)
底层基于[__alloc_bootmem_low_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L421) | +| NUMA结构的分配函数 | | | +| alloc_bootmem_node(pgdat, size) | [alloc_bootmem_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L132)
[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L777)
[ ___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)
[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L383)
[ ___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) | +| alloc_bootmem_node_nopanic(pgdat, size) | [alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L134)
[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L738)
[___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)
[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L344)
[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) | +| alloc_bootmem_pages_node(pgdat, size) | [alloc_bootmem_pages_node](http://lxr.free-electrons.com/source/include/linux/bootmem.h?v=4.7#L136)
[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)
[___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)
[__alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L344)
[___alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L317) | +| 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)
[__alloc_bootmem_node_nopanic](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L344)
[___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)
[__alloc_bootmem_low_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L861)[___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L747)
[___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)
[__alloc_bootmem_low_node](http://lxr.free-electrons.com/source/mm/bootmem.c?v=4.7#L444)[___alloc_bootmem_node](http://lxr.free-electrons.com/source/mm/nobootmem.c?v=4.7#L353)
[___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 ------- diff --git a/study/kernel/02-memory/03-initialize/1.c b/study/kernel/02-memory/03-initialize/1.c deleted file mode 100644 index 1fa9fc7..0000000 --- a/study/kernel/02-memory/03-initialize/1.c +++ /dev/null @@ -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; -} -``` \ No newline at end of file