vue做单页面网站,网站开发的学习路线,对网站做数据分析,中医院网站源码说明
Linux启动log中会显示平台的内存信息#xff0c;公司SOC平台#xff0c;物理DRAM实际size是128M#xff0c;但是启动log中total size不足128MB#xff0c;并且预留内存#xff08;82272K reserved#xff09;过多#xff0c;启动log如下#xff1a;
Memory: 480…说明
Linux启动log中会显示平台的内存信息公司SOC平台物理DRAM实际size是128M但是启动log中total size不足128MB并且预留内存82272K reserved过多启动log如下
Memory: 48032K/130304K available (3478K kernel code, 500K rwdata, 1504K rodata, 124K init, 212K bss, 82272K reserved, 0K cma-reserved)total size130304K预留size 82272K相减得到剩余size48032K。
分析
平台使用memblock管理早期内存分配打开memblock debug重启后启动log如下
memblock_reserve: [0x0000000080200000-0x00000000807bdfff] setup_bootmem0x86/0x162
memblock_reserve: [0x0000000082dcd000-0x0000000082dd2fff] setup_bootmem0xde/0x162
memblock_reserve: [0x0000000080000000-0x000000008007ffff] setup_bootmem0x100/0x162
memblock_reserve: [0x0000000080000000-0x000000008007ffff] early_init_fdt_scan_reserved_mem0x46/0x76
memblock_reserve: [0x0000000080000000-0x000000008003ffff] __fdt_scan_reserved_mem0x20a/0x27a
memblock_reserve: [0x000000008377e000-0x000000008393ffff] fdt_init_reserved_mem0x306/0x42a
memblock_reserve: [0x0000000083940000-0x0000000087f3ffff] fdt_init_reserved_mem0x360/0x42a
Ion: Ion memory setup at 0x0000000083940000 size 70 MiB
OF: reserved mem: initialized node ion, compatible id ion-region
MEMBLOCK configuration:memory size 0x0000000007f40000 reserved size 0x0000000004e06000memory.cnt 0x1memory[0x0] [0x0000000080000000-0x0000000087f3ffff], 0x0000000007f40000 bytes flags: 0x0reserved.cnt 0x4reserved[0x0] [0x0000000080000000-0x000000008007ffff], 0x0000000000080000 bytes flags: 0x0reserved[0x1] [0x0000000080200000-0x00000000807bdfff], 0x00000000005be000 bytes flags: 0x0reserved[0x2] [0x0000000082dcd000-0x0000000082dd2fff], 0x0000000000006000 bytes flags: 0x0reserved[0x3] [0x000000008377e000-0x0000000087f3ffff], 0x00000000047c2000 bytes flags: 0x0
memblock_reserve: [0x000000008377d000-0x000000008377dfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008377c000-0x000000008377cfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008377b000-0x000000008377bfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008377a000-0x000000008377afff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083779000-0x0000000083779fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083778000-0x0000000083778fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083777000-0x0000000083777fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083776000-0x0000000083776fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083775000-0x0000000083775fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083774000-0x0000000083774fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083773000-0x0000000083773fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083772000-0x0000000083772fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083771000-0x0000000083771fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083770000-0x0000000083770fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008376f000-0x000000008376ffff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008376e000-0x000000008376efff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008376d000-0x000000008376dfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008376c000-0x000000008376cfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008376b000-0x000000008376bfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008376a000-0x000000008376afff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083769000-0x0000000083769fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083768000-0x0000000083768fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083767000-0x0000000083767fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083766000-0x0000000083766fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083765000-0x0000000083765fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083764000-0x0000000083764fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083763000-0x0000000083763fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083762000-0x0000000083762fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083761000-0x0000000083761fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083760000-0x0000000083760fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008375f000-0x000000008375ffff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008375e000-0x000000008375efff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008375d000-0x000000008375dfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008375c000-0x000000008375cfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008375b000-0x000000008375bfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008375a000-0x000000008375afff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083759000-0x0000000083759fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083758000-0x0000000083758fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083757000-0x0000000083757fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083756000-0x0000000083756fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083755000-0x0000000083755fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083754000-0x0000000083754fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083753000-0x0000000083753fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083752000-0x0000000083752fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083751000-0x0000000083751fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083750000-0x0000000083750fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008374f000-0x000000008374ffff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008374e000-0x000000008374efff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008374d000-0x000000008374dfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008374c000-0x000000008374cfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008374b000-0x000000008374bfff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008374a000-0x000000008374afff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083749000-0x0000000083749fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083748000-0x0000000083748fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083747000-0x0000000083747fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083746000-0x0000000083746fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083745000-0x0000000083745fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083744000-0x0000000083744fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083743000-0x0000000083743fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083742000-0x0000000083742fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083741000-0x0000000083741fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x0000000083740000-0x0000000083740fff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008373f000-0x000000008373ffff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008373e000-0x000000008373efff] memblock_alloc_range_nid0x96/0xc2
memblock_reserve: [0x000000008373d000-0x000000008373dfff] memblock_alloc_range_nid0x96/0xc2
Zone ranges:DMA32 [mem 0x0000000080000000-0x0000000087f3ffff]Normal empty
Movable zone start for each node
Early memory node rangesnode 0: [mem 0x0000000080000000-0x0000000087f3ffff]
Initmem setup node 0 [mem 0x0000000080000000-0x0000000087f3ffff]
On node 0 totalpages: 32576
memblock_alloc_try_nid: 1835008 bytes align0x40 nid0 from0x0000000000000000 max_addr0x0000000000000000 alloc_node_mem_map.constprop.00x4c/0xd0
memblock_reserve: [0x000000008357d000-0x000000008373cfff] memblock_alloc_range_nid0x96/0xc2DMA32 zone: 446 pages used for memmapDMA32 zone: 0 pages reservedDMA32 zone: 32576 pages, LIFO batch:7
memblock_alloc_try_nid: 32 bytes align0x40 nid0 from0x0000000000000000 max_addr0x0000000000000000 setup_usemap.constprop.00x48/0x6c
memblock_reserve: [0x000000008357cfc0-0x000000008357cfdf] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 64 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 paging_init0x228/0x2a2
memblock_reserve: [0x000000008357cf80-0x000000008357cfbf] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 96564 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565648-0x000000008357cf7b] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 44 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565618-0x0000000083565643] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 44 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x00000000835655e8-0x0000000083565613] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 44 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x00000000835655b8-0x00000000835655e3] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 44 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565588-0x00000000835655b3] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 44 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565558-0x0000000083565583] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 47 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565528-0x0000000083565556] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 47 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x00000000835654f8-0x0000000083565526] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 47 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x00000000835654c8-0x00000000835654f6] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 47 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565498-0x00000000835654c6] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 47 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565468-0x0000000083565496] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 49 bytes align0x8 nid-1 from0x0000000000000000 max_addr0x0000000000000000 early_init_dt_alloc_memory_arch0x16/0x3e
memblock_reserve: [0x0000000083565430-0x0000000083565460] memblock_alloc_range_nid0x96/0xc2
SBI specification v0.3 detected
SBI implementation ID0x1 Version0x9
SBI v0.2 TIME extension detected
SBI v0.2 IPI extension detected
SBI v0.2 RFENCE extension detected
riscv: ISA extensions acdfimsuv
riscv: ELF capabilities acdfimv
memblock_alloc_try_nid: 229 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 start_kernel0x82/0x346
memblock_reserve: [0x0000000083565340-0x0000000083565424] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 229 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 start_kernel0xb2/0x346
memblock_reserve: [0x0000000083565240-0x0000000083565324] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 4096 bytes align0x1000 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_alloc_alloc_info0x44/0x78
memblock_reserve: [0x0000000083564000-0x0000000083564fff] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 32768 bytes align0x1000 nid-1 from0x0000000080000000 max_addr0x0000000000000000 setup_per_cpu_areas0x2c/0x66
memblock_reserve: [0x000000008355c000-0x0000000083563fff] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 8 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_setup_first_chunk0x13a/0x36e
memblock_reserve: [0x0000000083565200-0x0000000083565207] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 8 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_setup_first_chunk0x168/0x36e
memblock_reserve: [0x00000000835651c0-0x00000000835651c7] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 4 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_setup_first_chunk0x178/0x36e
memblock_reserve: [0x0000000083565180-0x0000000083565183] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 8 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_setup_first_chunk0x188/0x36e
memblock_reserve: [0x0000000083565140-0x0000000083565147] memblock_alloc_range_nid0x96/0xc2
pcpu-alloc: s0 r0 d32768 u32768 alloc1*32768
pcpu-alloc: [0] 0
memblock_alloc_try_nid: 240 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_setup_first_chunk0x224/0x36e
memblock_reserve: [0x0000000083565040-0x000000008356512f] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 128 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_alloc_first_chunk0x5c/0x19a
memblock_reserve: [0x000000008355bf80-0x000000008355bfff] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 1024 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_alloc_first_chunk0xa4/0x19a
memblock_reserve: [0x000000008355bb80-0x000000008355bf7f] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 1032 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_alloc_first_chunk0xc2/0x19a
memblock_reserve: [0x000000008355b740-0x000000008355bb47] memblock_alloc_range_nid0x96/0xc2
memblock_alloc_try_nid: 256 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 pcpu_alloc_first_chunk0xd8/0x19a
memblock_reserve: [0x000000008355b640-0x000000008355b73f] memblock_alloc_range_nid0x96/0xc2
memblock_free: [0x0000000083564000-0x0000000083564fff] start_kernel0xe0/0x346
Built 1 zonelists, mobility grouping on. Total pages: 32130
Kernel command line: rootfstypesquashfs rootwait ro root/dev/mtdblock4 mtdparts10000000.cvi-spif:1024K(fip),3072K(BOOT),64K(ENV),64K(ENV_BAK),10240K(ROOTFS),512K(DATA) consolettyS0,115200 earlyconsbi loglevel9 riscv.fwsz0x80000 memblockdebug
memblock_alloc_try_nid: 131072 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 alloc_large_system_hash0x108/0x1d0
memblock_reserve: [0x000000008353b640-0x000000008355b63f] memblock_alloc_range_nid0x96/0xc2
Dentry cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
memblock_alloc_try_nid: 65536 bytes align0x40 nid-1 from0x0000000000000000 max_addr0x0000000000000000 alloc_large_system_hash0x108/0x1d0
memblock_reserve: [0x000000008352b640-0x000000008353b63f] memblock_alloc_range_nid0x96/0xc2
Inode-cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
Sorting __ex_table...
mem auto-init: stack:off, heap alloc:off, heap free:off
Memory: 48032K/130304K available (3478K kernel code, 500K rwdata, 1504K rodata, 124K init, 212K bss, 82272K reserved, 0K cma-reserved)
...total size由来
Linux感知的内存total size可以通过uboot bootargs传递也可以通过dts配置公司SOC使用dts配置如下
//file: xxx.dtsi #include xxx.h/ {memory80000000 {device_type memory;reg 0x00 XXXMMAP_KERNEL_MEMORY_ADDR 0x00 XXXMMAP_KERNEL_MEMORY_SIZE;};....
};为兼容多个平台dts中使用头文件中的宏定义来定义物理内存地址和大小头文件由脚本生成如下
//file: memmap.pyDRAM_BASE 0x80000000DRAM_SIZE 128 * SIZE_1M# 小核预留FREERTOS_SIZE 768 * SIZE_1K....# # memoryDRAM_BASE in .dts.# # Ignore the area of FreeRTOS in u-boot and kernelKERNEL_MEMORY_ADDR DRAM_BASEKERNEL_MEMORY_SIZE DRAM_SIZE - FREERTOS_SIZE因此kernel感知的实际total size128MB * 1024 - 768 130304K与启动log匹配。
memblock分配器初始化前的预留内存占用
memblock初始化成功的配置
MEMBLOCK configuration:memory size 0x0000000007f40000 reserved size 0x0000000004e06000 //总size(130304K)和初始化前的预留内存占用sizememory.cnt 0x1memory[0x0] [0x0000000080000000-0x0000000087f3ffff], 0x0000000007f40000 bytes flags: 0x0 //总size(130304K)reserved.cnt 0x4 // 初始化前的预留内存占用reserved[0x0] [0x0000000080000000-0x000000008007ffff], 0x0000000000080000 bytes flags: 0x0reserved[0x1] [0x0000000080200000-0x00000000807bdfff], 0x00000000005be000 bytes flags: 0x0reserved[0x2] [0x0000000082dcd000-0x0000000082dd2fff], 0x0000000000006000 bytes flags: 0x0reserved[0x3] [0x000000008377e000-0x0000000087f3ffff], 0x00000000047c2000 bytes flags: 0x04块预留内存的详细分配记录内存段相邻时会合并成一块
memblock_reserve: [0x0000000080200000-0x00000000807bdfff] setup_bootmem0x86/0x162
memblock_reserve: [0x0000000082dcd000-0x0000000082dd2fff] setup_bootmem0xde/0x162
memblock_reserve: [0x0000000080000000-0x000000008007ffff] setup_bootmem0x100/0x162
memblock_reserve: [0x0000000080000000-0x000000008007ffff] early_init_fdt_scan_reserved_mem0x46/0x76
memblock_reserve: [0x0000000080000000-0x000000008003ffff] __fdt_scan_reserved_mem0x20a/0x27a
memblock_reserve: [0x000000008377e000-0x000000008393ffff] fdt_init_reserved_mem0x306/0x42a
memblock_reserve: [0x0000000083940000-0x0000000087f3ffff] fdt_init_reserved_mem0x360/0x42a分配代码
//file: arch/riscv/mm/init.c
void __init setup_bootmem(void)
{phys_addr_t mem_start 0;phys_addr_t start, end 0;phys_addr_t vmlinux_end __pa_symbol(_end);phys_addr_t vmlinux_start __pa_symbol(_start);u64 i;/* Find the memory region containing the kernel */for_each_mem_range(i, start, end) {phys_addr_t size end - start;if (!mem_start)mem_start start;if (start vmlinux_start vmlinux_end end)BUG_ON(size 0);}/** The maximal physical memory size is -PAGE_OFFSET.* Make sure that any memory beyond mem_start (-PAGE_OFFSET) is removed* as it is unusable by kernel.*/memblock_enforce_memory_limit(-PAGE_OFFSET);/* Reserve from the start of the kernel to the end of the kernel */memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);max_pfn PFN_DOWN(memblock_end_of_DRAM());max_low_pfn max_pfn;set_max_mapnr(max_low_pfn);#ifdef CONFIG_BLK_DEV_INITRDsetup_initrd();
#endif /* CONFIG_BLK_DEV_INITRD *//** Avoid using early_init_fdt_reserve_self() since __pa() does* not work for DTB pointers that are fixmap addresses*/memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));if (firmware_size PAGE_SIZE firmware_size LOAD_OFFSET)memblock_reserve(__pa(PAGE_OFFSET), firmware_size);elsememblock_reserve(__pa(PAGE_OFFSET), LOAD_OFFSET);...
} 根据代码可知预留内存占用如下
kernel code等大约6MB大小是通过链接脚本ld.s中的符号vmlinux_endvmlinux_start相减所得。opensbi512KB大小是通过uboot传递过来的bootargsriscv.fwsz0x80000所得。dtb32KB大小fdt_totalsize(dtb_early_va)dts中定义的ion(70MB)。dts中定义的其它reserved_mem大约2MB根据分配记录memblock_reserve可以获取分配的具体信息。
memblock分配器初始化后的预留内存占用
启动logMEMBLOCK configuration后的分配打印就是memblock初始化成功后的预留内存占用。根据代码和分配记录可知预留内存占用主要是内核机制大约2.3MB有一些大头如下
memmapsetup_per_cpu_areasDentry cache hash table entriesInode-cache hash table entries
不同内核机制的分配待分析。
预留内存占用统计
将预留内存占用memblock_reserve累加再减去预留内存释放memblock_free计算出总的预留内存占用为82269K。
问题
统计出的总预留内存size和打印不匹配
启动log中的预留内存总size82272K reserved和实际计算出的总size82269K不一致是因为打印启动log时会做页对齐对齐后就一样了如下
// file: linux_5.10/mm/page_alloc.c
void __init mem_init_print_info(const char *str)
{...pr_info(Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved
#ifdef CONFIG_HIGHMEM, %luK highmem
#endif%s%s)\n,nr_free_pages() (PAGE_SHIFT - 10),physpages (PAGE_SHIFT - 10),codesize 10, datasize 10, rosize 10,(init_data_size init_code_size) 10, bss_size 10,(physpages - totalram_pages() - totalcma_pages) (PAGE_SHIFT - 10), // 根据内存页size 对齐totalcma_pages (PAGE_SHIFT - 10),
#ifdef CONFIG_HIGHMEMtotalhigh_pages() (PAGE_SHIFT - 10),
#endifstr ? , : , str ? str : );
}
