- 一、 /etc/init.cfg 系统默认cfg：启动lo回环网卡
- 1.1 init.Hi3516DV300.cfg：持载debugfs到/sys/kernel/debug
- 二、/system/etc/init 下的cfg
- 2.1 foundation.cfg 用户程序框架子系统 ：挂载cgroup到/dev/memcg
- 2.2 samgr_L2.cfg 用户程序框架子系统：启动samgr 服务
本系列文章汇总：
- 《【鸿蒙OS开发入门】01 - 搭建Ubuntu虚拟机开发环境》
- 《【鸿蒙OS开发入门】02 - 启动流程代码分析之Uboot 第一阶段：之解压并引导加载u-boot.bin》
- 《【鸿蒙OS开发入门】03 - 启动流程代码分析之Uboot 第二阶段：之board_init初始化》
- 《【鸿蒙OS开发入门】04 - 启动流程代码分析之Uboot 第二阶段：之U_BOOT_CMD原理》
- 《【鸿蒙OS开发入门】05 - 启动流程代码分析之Uboot 第二阶段：之bootm引导加载Kernel OS》
- 《【鸿蒙OS开发入门】06 - 启动流程代码分析之KernelOS：之启动Linux-4.19 Kernel内核》
- 《【鸿蒙OS开发入门】07 - 安装docker环境编译openharmony 2.0代码》
- 《【鸿蒙OS开发入门】08 - 启动流程代码分析之KernelOS：之启动 liteos_a 内核》
- 《【鸿蒙OS开发入门】09 - 启动流程代码分析之KernelOS：之启动Linux-4.19 Kernel内核 中do_basic_setup()所干的大事》
- 《【鸿蒙OS开发入门】10 - 启动流程代码分析之第一个用户态进程：init 进程》
- 《【鸿蒙OS开发入门】11 - 启动流程代码分析之第一个用户态进程：init 进程 之 Services简介》
- 《【鸿蒙OS开发入门】12 - 启动流程代码分析之第一个用户态进程：init 进程 之 pre-init 任务详解》
- 《【鸿蒙OS开发入门】13 - 启动流程代码分析之第一个用户态进程：init 进程 之 init 任务详解》
- 《【鸿蒙OS开发入门】14 - 启动流程代码分析之第一个用户态进程：init 进程 之 post-init 任务详解》
- 《【鸿蒙OS开发入门】15 - 启动流程代码分析之第一个用户态进程：init 进程 之 libuv 做了啥？》
- 《【鸿蒙OS开发入门】16 - 重头搭建Ubuntu新环境编译OpenHarmony 3.0 LTS》
在前面，我们分析到：pre-init 阶段，主要是做了启动ueventd服务，以及挂载vendor、userdata 这两个分区。
本文，我们来看下，init 阶段又做了什么呢?
注：本文先看正常开机的流程，有关recover模式，或updater情况下，我们后续再单独分析
# basestartupinit_liteservicessrcmain.c
int main(int argc, char **argv)
{
......
// 4. 分别执行pre-init、init、post-init 等相关的事情
InitReadCfg();
--------->
+ ParseInitCfg(INIT_CONFIGURATION_FILE); // "/etc/init.cfg"
+ DumpAllServices(); // 打印所有的服务信息，系统中所有现有的服务保存在 static Service* g_services 中，通过g_servicesCnt来进行索引计数。
+ DoJob("pre-init"); // 执行 `/etc/init.cfg` 中 `pre-init`的内容
+ DoJob("init"); // 执行 `/etc/init.cfg` 中 `init`的内容
+ DoJob("post-init"); // 执行 `/etc/init.cfg` 中 `post-init`的内容
+ ReleaseAllJobs(); // 释放init.cfg中所有的jobs 命令所占用的空间
<---------
......
}
DoJob("init");的作用是，触发启动 json cfg文件中所有init 字段的命令，我们分别来看看这些命令的功能吧。
在init.cfg加载了"/etc/init.usb.cfg", "/etc/init.usb.configfs.cfg", "/etc/init.Hi3516DV300.usb.cfg", "/etc/init.Hi3516DV300.cfg"这几个config，会把它们的信息全部整合进来。
可以看出，在 init.cfg 中，主要是做了如下事情：
- 创建相关的目录，修改各设备节点的权限，配置一些参数。
- 启动 lo 回环网卡，配置hostname为localhost， domainname为localdomain。
# base/startup/init_lite/services/etc/init.cfg
{
"import" : [
"/etc/init.usb.cfg",
"/etc/init.usb.configfs.cfg",
"/etc/init.usb.cfg",
"/etc/init.Hi3516DV300.usb.cfg",
"/etc/init.Hi3516DV300.cfg"
],
],
"jobs" : [ {
"name" : "init",
"cmds" : [
"copy /proc/cmdline /dev/urandom",
"copy /system/etc/prop.default /dev/urandom",
"symlink /proc/self/fd/0 /dev/stdin",
"symlink /proc/self/fd/1 /dev/stdout",
"symlink /proc/self/fd/2 /dev/stderr",
"symlink /system/bin /bin",
"symlink /system/etc /etc",
"symlink /sys/kernel/debug /d",
"symlink /system/vendor /vendor",
"mkdir /dev/stune/foreground",
"mkdir /dev/stune/background",
"mkdir /dev/stune/top-app",
"mkdir /dev/stune/rt",
"chown system system /dev/stune",
"chown system system /dev/stune/foreground",
"chown system system /dev/stune/background",
"chown system system /dev/stune/top-app",
"chown system system /dev/stune/rt",
"chown system system /dev/stune/tasks",
"chown system system /dev/stune/foreground/tasks",
"chown system system /dev/stune/background/tasks",
"chown system system /dev/stune/top-app/tasks",
"chown system system /dev/stune/rt/tasks",
"chmod 0664 /dev/stune/tasks",
"chmod 0664 /dev/stune/foreground/tasks",
"chmod 0664 /dev/stune/background/tasks",
"chmod 0664 /dev/stune/top-app/tasks",
"chmod 0664 /dev/stune/rt/tasks",
"mkdir /dev/blkio/background",
"chown system system /dev/blkio",
"chown system system /dev/blkio/background",
"chown system system /dev/blkio/tasks",
"chown system system /dev/blkio/background/tasks",
"chmod 0664 /dev/blkio/tasks",
"chmod 0664 /dev/blkio/background/tasks",
"write /dev/blkio/blkio.weight 1000",
"write /dev/blkio/background/blkio.weight 500",
"write /dev/blkio/blkio.group_idle 0",
"write /dev/blkio/background/blkio.group_idle 0",
"mount configfs none /config nodev noexec nosuid",
"chmod 0770 /config/sdcardfs",
"chown system package_info /config/sdcardfs",
"mkdir /mnt/secure 0700 root root",
"mkdir /mnt/secure/asec 0700 root root",
"mkdir /mnt/asec 0755 root system",
"mkdir /mnt/obb 0755 root system",
"mkdir /mnt/media_rw 0750 root media_rw",
"mkdir /mnt/user 0755 root root",
"mkdir /mnt/user/0 0755 root root",
"mkdir /mnt/expand 0771 system system",
"mkdir /mnt/appfuse 0711 root root",
"mkdir /mnt/runtime 0700 root root",
"mkdir /mnt/runtime/default 0755 root root",
"mkdir /mnt/runtime/default/self 0755 root root",
"mkdir /mnt/runtime/read 0755 root root",
"mkdir /mnt/runtime/read/self 0755 root root",
"mkdir /mnt/runtime/write 0755 root root",
"mkdir /mnt/runtime/write/self 0755 root root",
"mkdir /mnt/runtime/full 0755 root root",
"mkdir /mnt/runtime/full/self 0755 root root",
"symlink /storage/self/primary /sdcard",
"symlink /storage/self/primary /mnt/sdcard",
"symlink /mnt/user/0/primary /mnt/runtime/default/self/primary",
"write /proc/sys/kernel/panic_on_oops 1",
"write /proc/sys/kernel/hung_task_timeout_secs 0",
"write /proc/cpu/alignment 4",
"write /proc/sys/kernel/sched_tunable_scaling 0",
"write /proc/sys/kernel/sched_latency_ns 10000000",
"write /proc/sys/kernel/sched_wakeup_granularity_ns 2000000",
"write /proc/sys/kernel/sched_child_runs_first 0",
"write /proc/sys/kernel/randomize_va_space 2",
"write /proc/sys/vm/mmap_min_addr 32768",
"write /proc/sys/net/ipv4/ping_group_range 0 2147483647",
"write /proc/sys/net/unix/max_dgram_qlen 600",
"write /proc/sys/kernel/sched_rt_runtime_us 950000",
"write /proc/sys/kernel/sched_rt_period_us 1000000",
"write /proc/sys/net/core/rmem_max 262144",
"write /proc/sys/net/core/wmem_max 262144",
"write /proc/sys/net/ipv4/fwmark_reflect 1",
"write /proc/sys/net/ipv6/fwmark_reflect 1",
"write /proc/sys/net/ipv4/tcp_fwmark_accept 1",
"write /proc/sys/net/ipv4/conf/all/accept_redirects 0",
"write /proc/sys/net/ipv6/conf/all/accept_redirects 0",
"chmod 0400 /proc/net/fib_trie",
"chown system system /dev/cpuctl",
"chown system system /dev/cpuctl/tasks",
"chmod 0666 /dev/cpuctl/tasks",
"write /dev/cpuctl/cpu.rt_period_us 1000000",
"write /dev/cpuctl/cpu.rt_runtime_us 950000",
"mkdir /dev/cpuset/foreground",
"copy /dev/cpuset/cpus /dev/cpuset/foreground/cpus",
"copy /dev/cpuset/mems /dev/cpuset/foreground/mems",
"mkdir /dev/cpuset/background",
"copy /dev/cpuset/cpus /dev/cpuset/background/cpus",
"copy /dev/cpuset/mems /dev/cpuset/background/mems",
"mkdir /dev/cpuset/system-background",
"copy /dev/cpuset/cpus /dev/cpuset/system-background/cpus",
"copy /dev/cpuset/mems /dev/cpuset/system-background/mems",
"mkdir /dev/cpuset/restricted",
"copy /dev/cpuset/cpus /dev/cpuset/restricted/cpus",
"copy /dev/cpuset/mems /dev/cpuset/restricted/mems",
"mkdir /dev/cpuset/top-app",
"copy /dev/cpuset/cpus /dev/cpuset/top-app/cpus",
"copy /dev/cpuset/mems /dev/cpuset/top-app/mems",
"chown system system /dev/cpuset",
"chown system system /dev/cpuset/foreground",
"chown system system /dev/cpuset/background",
"chown system system /dev/cpuset/system-background",
"chown system system /dev/cpuset/top-app",
"chown system system /dev/cpuset/restricted",
"chown system system /dev/cpuset/tasks",
"chown system system /dev/cpuset/foreground/tasks",
"chown system system /dev/cpuset/background/tasks",
"chown system system /dev/cpuset/system-background/tasks",
"chown system system /dev/cpuset/top-app/tasks",
"chown system system /dev/cpuset/restricted/tasks",
"chmod 0775 /dev/cpuset/system-background",
"chmod 0664 /dev/cpuset/foreground/tasks",
"chmod 0664 /dev/cpuset/background/tasks",
"chmod 0664 /dev/cpuset/system-background/tasks",
"chmod 0664 /dev/cpuset/top-app/tasks",
"chmod 0664 /dev/cpuset/restricted/tasks",
"chmod 0664 /dev/cpuset/tasks",
"chown system system /proc/pressure/memory",
"chmod 0664 /proc/pressure/memory",
"chown root net_bw_acct /proc/net/xt_qtaguid/ctrl",
"chown root net_bw_stats /proc/net/xt_qtaguid/stats",
"chmod 0644 /dev/xt_qtaguid",
"chown root root /dev/cg2_bpf",
"chmod 0600 /dev/cg2_bpf",
"mount bpf bpf /sys/fs/bpf nodev noexec nosuid",
"mkdir /dev/fscklogs 0770 root system",
"mount pstore pstore /sys/fs/pstore nodev noexec nosuid",
"chown system log /sys/fs/pstore",
"chmod 0550 /sys/fs/pstore",
"chown system log /sys/fs/pstore/console-ramoops",
"chmod 0440 /sys/fs/pstore/console-ramoops",
"chown system log /sys/fs/pstore/console-ramoops-0",
"chmod 0440 /sys/fs/pstore/console-ramoops-0",
"chown system log /sys/fs/pstore/pmsg-ramoops-0",
"chmod 0440 /sys/fs/pstore/pmsg-ramoops-0",
"write /proc/sys/abi/swp 1",
"symlink /proc/self/fd /dev/fd",
"export DOWNLOAD_CACHE /data/cache",
"setrlimit RLIMIT_NICE 40 40",
"setrlimit RLIMIT_NOFILE 32768 32768",
"write /sys/class/leds/vibrator/trigger transient",
"write /dev/cpu_variant:${ro.bionic.arch} ${ro.bionic.cpu_variant}",
"chmod 0444 /dev/cpu_variant:${ro.bionic.arch}",
"write /dev/cpu_variant:${ro.bionic.2nd_arch} ${ro.bionic.2nd_cpu_variant}",
"chmod 0444 /dev/cpu_variant:${ro.bionic.2nd_arch}",
"chown system system /sys/power/state",
"chown system system /sys/power/wakeup_count",
"chmod 0660 /sys/power/state",
"ifup lo",
"hostname localhost",
"domainname localdomain"
]
},
1.1 init.Hi3516DV300.cfg：持载debugfs到/sys/kernel/debug
- 挂载 debugfs 到/sys/kernel/debug中。
- 修改设备角色为 peripheral，即设备。
# device/hisilicon/hi3516dv300/build/rootfs/init.Hi3516DV300.cfg
{
"import" : [
"init.${ro.hardware}.usb.cfg"
],
"jobs" : [ {
"name" : "init",
"cmds" : [
"mount debugfs /sys/kernel/debug /sys/kernel/debug mode=755",
"write /sys/kernel/debug/hisi_inno_phy/role peripheral"
]
}
存在 init 的cfg 总共有这些文件:
./foundation/appexecfwk/standard/sa_profile/foundation.cfg:3: "name" : "init", ./foundation/distributedschedule/samgr/services/samgr/native/samgr_L2.cfg:3: "name" : "init",
2.1 foundation.cfg 用户程序框架子系统 ：挂载cgroup到/dev/memcg
用户程序框架子系统 初始化过程中，主要做了如下事情：
-
挂载 cgroup 的memory、cpuset、cpu、freezer这几个到 /dev/memcg 目录下
cgroups子系统： Linux CGroup全称Linux Control Group， 是Linux内核的一个功能，用来限制，控制与分离一个进程组群的资源（如CPU、内存、磁盘输入输出等），其最早的名称为进程容器（process containers）。详细可参考：《LINUX CGROUP总结》cgroups可控制的子系统主要如下：
cpu 子系统，主要限制进程的 cpu 使用率。
cpuacct 子系统，可以统计 cgroups 中的进程的 cpu 使用报告。
cpuset 子系统，可以为 cgroups 中的进程分配单独的 cpu 节点或者内存节点。
memory 子系统，可以限制进程的 memory 使用量。
blkio 子系统，可以限制进程的块设备 io。
devices 子系统，可以控制进程能够访问某些设备。
net_cls 子系统，可以标记 cgroups 中进程的网络数据包，然后可以使用 tc 模块（traffic control）对数据包进行控制。
net_prio — 这个子系统用来设计网络流量的优先级
freezer 子系统，可以挂起或者恢复 cgroups 中的进程。
ns 子系统，可以使不同 cgroups 下面的进程使用不同的 namespace
hugetlb — 这个子系统主要针对于HugeTLB系统进行限制，这是一个大页文件系统。
# foundation/appexecfwk/standard/sa_profile/foundation.cfg
{
"jobs" : [{
"name" : "init",
"cmds" : [
"mkdir /dev/memcg",
"mount cgroup none /dev/memcg memory",
"chown system system /dev/memcg",
"chown system system /dev/memcg/tasks",
"chown system system /dev/memcg/memory.oom_control",
"chown system system /dev/memcg/cgroup.event_control",
"chown system system /dev/memcg/memory.pressure_level",
"chmod 0755 /dev/memcg",
"chmod 0755 /dev/memcg/tasks",
"chmod 0755 /dev/memcg/memory.oom_control",
"chmod 0755 /dev/memcg/cgroup.event_control",
"chmod 0755 /dev/memcg/memory.pressure_level",
"mkdir /dev/cpuset",
"mount cgroup none /dev/cpuset cpuset",
"mkdir /dev/cpuset/background",
"chown system system /dev/cpuset",
"chown system system /dev/cpuset/tasks",
"chown system system /dev/cpuset/background",
"chown system system /dev/cpuset/background/tasks",
"chmod 0755 /dev/cpuset",
"chmod 0755 /dev/cpuset/tasks",
"chmod 0755 /dev/cpuset/background",
"chmod 0755 /dev/cpuset/background/tasks",
"write /dev/cpuset/background/cpuset.cpus 0",
"mkdir /dev/cpuctl",
"mount cgroup none /dev/cpuctl cpu",
"mkdir /dev/cpuctl/background",
"chown system system /dev/cpuctl",
"chown system system /dev/cpuctl/tasks",
"chown system system /dev/cpuctl/background",
"chown system system /dev/cpuctl/background/tasks",
"chmod 0755 /dev/cpuctl",
"chmod 0755 /dev/cpuctl/tasks",
"chmod 0755 /dev/cpuctl/background",
"chmod 0755 /dev/cpuctl/background/tasks",
"write /dev/cpuctl/background/cpu.shares 512",
"mkdir /dev/freezer",
"mount cgroup none /dev/freezer freezer",
"mkdir /dev/freezer/frozen",
"mkdir /dev/freezer/thawed",
"chown system system /dev/freezer",
"chown system system /dev/freezer/frozen",
"chown system system /dev/freezer/frozen/tasks",
"chown system system /dev/freezer/thawed",
"chown system system /dev/freezer/thawed/tasks",
"chmod 0755 /dev/freezer",
"chmod 0755 /dev/freezer/frozen",
"chmod 0755 /dev/freezer/frozen/tasks",
"chmod 0755 /dev/freezer/thawed",
"chmod 0755 /dev/freezer/thawed/tasks",
"write /dev/freezer/frozen/freezer.state FROZEN",
"write /dev/freezer/thawed/freezer.state THAWED"
]
}, {
"name" : "boot",
"cmds" : [
"chown radio system /sys/power/wake_lock",
"chown radio system /sys/power/wake_unlock",
"chmod 0664 /sys/power/wakeup_count",
"start foundation"
]
}
],
"services" : [{
"name" : "foundation",
"path" : ["/system/bin/sa_main", "/system/profile/foundation.xml"],
"importance" : -20,
"uid" : "system",
"gid" : ["system"],
"caps" : ["SYS_PTRACE", "KILL"]
}
]
}
2.2 samgr_L2.cfg 用户程序框架子系统：启动samgr 服务
# foundation/distributedschedule/samgr/services/samgr/native/samgr_L2.cfg
{
"jobs" : [{
"name" : "init",
"cmds" : [
"mkdir /data/sadata_de",
"chmod 755 /data/sadata_de",
"chown system system /data/sadata_de",
"mkdir /data/sadata_de/samgr",
"chmod 755 /data/sadata_de/samgr",
"chown system system /data/sadata_de/samgr",
"start samgr"
]
}
],
"services" : [{
"name" : "samgr",
"path" : ["/system/bin/samgr"],
"uid" : "system",
"gid" : ["system"]
}
]
}
init阶段的任务也不多，主要是挂载调试子系统，启动用户程序框架子系统samgr，
看起来启动过程中，大头应该在post-init中，下篇文章我们来看下吧。
