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debian内核代码执行流程(三)

接续《debian内核代码执行流程(二)》未完成部分

 

下面这行输出信息是启动udevd进程产生的输出信息:

[    3.306217] udevd[49]: starting version 175

175是udevd的版本号。

 

根据《essential linux device drivers》中关于udev的说明(英文书140页),设备可以分成热插拔和冷插拔。

热插拔是在已经运行的系统中连接的设备,冷插拔是系统启动前插入的设备。

当系统检测到热插拔设备时,系统使用netlink socket向用户空间发送uevents。

在用户端,udev管理设备的创建和删除、接收uevent,管理热插拔设备。udev也可以处理冷插拔。因为udev是用户程序,只能在内核驱动后才开始执行,需要特殊的机制来模拟热插拔时间。

在启动时,内核在sysfs下为所有设备创建名为uevent的文件,然后向这些文件发送冷插拔时间。

当udev启动后,它会从sysfs中读取uevent,为每个冷插拔设备产生热插拔时间。

 

此时加载r8169.ko模块,执行r8169.ko模块的初始化函数,即rtl8169_init_module(drivers/net/ethernet/realtek/r8169.c).

之后调用rtl8169_pci_driver.probe函数,即rtl8169_init_one,rtl8169_init_one中输出下面信息:

[    3.346446] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded

rtl8169_init_one中调用pci_set_master,pci_set_master调用pcibios_set_master,输出下面信息:

[    2.854355] pcieport 0000:00:1c.0: setting latency timer to 64

下面信息是由setup_msi_irq输出的(但不知道是从哪个函数调用过去的):

[    2.854395] pcieport 0000:00:1c.0: irq 40 for MSI/MSI-X

rtl8169_init_one中继续输出下面信息:

[    3.346995] r8169 0000:04:00.0: eth0: RTL8102e at 0xf821a000, 00:e0:4c:26:51:75, XID 14c00000 IRQ 44

 

接着加载scsi模块,执行init_scsi,输出下面信息:

[    3.372657] SCSI subsystem initialized

 

接着加载usbcore模块,执行usb_init(drivers/usb/core/usb.c),usb_init调用usb_register(&usbfs_driver),输出下面信息:

[    3.384633] usbcore: registered new interface driver usbfs

usb_init调用usb_hub_init,usb_hub_init调用usb_register(&hub_driver),输出下面信息:

[    3.384665] usbcore: registered new interface driver hub

usb_hub_init中还创建了khubd线程,线程执行函数是hub_thread,用于监控hub状态变更。

usb_init中接着调用usb_register_device_driver(&usb_generic_driver,THIS_MODULE),输出下面信息:

[    3.384694] usbcore: registered new device driver usb

 

接着加载ehci-hcd模块,执行ehci_hcd_init(drivers/usb/host/ehci-hcd.c),输出下面信息:

[    3.385735] ehci_hcd: USB 2.0 Enhanced Host Controller (EHCI) Driver

ehci_hcd_init调用pci_register_driver(&PCI_DRIVER),而PCI_DRIVER即ehci_pci_driver.

之后会调用ehci_pci_driver.probe,即usb_hcd_pci_probe函数。

usb_hcd_pci_probe调用pci_set_master, pci_set_master调用pcibios_set_master,输出下面信息:

[    3.385794] ehci_hcd 0000:00:1d.7: setting latency timer to 64

usb_hcd_pci_probe接着调用usb_add_hcd,输出下面信息:

[    3.385798] ehci_hcd 0000:00:1d.7: EHCI Host Controller

usb_add_hcd调用usb_register_bus,输出下面信息:

[    3.385826] ehci_hcd 0000:00:1d.7: new USB bus registered, assigned bus number 1

usb_add_hcd调用hcd->driver->reset,即ehci_pci_hc_driver->reset,也即ehci_pci_setup,echi_pci_setup中输出下面信息:

[    3.385849] ehci_hcd 0000:00:1d.7: using broken periodic workaround[    3.385859] ehci_hcd 0000:00:1d.7: debug port 1

ehci_pci_setup调用echi_pci_reinit,ehci_pci_reinit调用pci_set_mwi,pci_set_mwi调用pci_set_cacheline_size, 输出下面信息:

[    3.389747] ehci_hcd 0000:00:1d.7: cache line size of 32 is not supported

usb_add_hcd调用usb_hcd_request_irqs,输出下面信息:

[    3.408370] ehci_hcd 0000:00:1d.7: irq 23, io mem 0xfdfff000

 

接着加载libata.ko模块,调用ata_init,输出下面信息:

[    3.412309] libata version 3.00 loaded.

 

接着加载uhci-hcd.ko模块,调用uhci_hcd_init,输出下面信息:

[    3.412721] uhci_hcd: USB Universal Host Controller Interface driver

 

接着加载floppy.ko模块,调用floppy_module_init, floppy_module_init调用floppy_init,floppy_init调用get_fdc_version,输出下面信息:

[    3.423746] FDC 0 is a post-1991 82077

 

上面ehci-hcd模块中usb_add_hcd调用hcd->driver->start,即ehci_pci_hc_driver->start,即ehci_run函数,输出下面信息:

[    3.424024] ehci_hcd 0000:00:1d.7: USB 2.0 started, EHCI 1.00

由此可见,模块加载可能是并发执行的。

usb_add_hcd中接着调用register_root_hub,register_root_hub调用usb_new_device,usb_new_device调用annouce_device,输出下面信息:

[    3.424090] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002[    3.424095] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1[    3.424100] usb usb1: Product: EHCI Host Controller[    3.424104] usb usb1: Manufacturer: Linux 3.2.57 ehci_hcd[    3.424107] usb usb1: SerialNumber: 0000:00:1d.7

 

调用hub_probe(不知道从哪儿开始调用的),输出下面信息:

[    3.424288] hub 1-0:1.0: USB hub found

hub_probe调用hub_configure,输出下面信息:

[    3.424294] hub 1-0:1.0: 8 ports detected

 

上面uhci_hcd_init调用pci_register_driver(&PCI_DRIVER),而PCI_DRIVER即uhci_pci_driver,

之后调用uhci_pci_driver.probe,即usb_hcd_pci_probe函数,跟前面ehci的例子类似输出下面信息:

[    3.425261] uhci_hcd 0000:00:1d.0: setting latency timer to 64[    3.425267] uhci_hcd 0000:00:1d.0: UHCI Host Controller[    3.425283] uhci_hcd 0000:00:1d.0: new USB bus registered, assigned bus number 2[    3.425315] uhci_hcd 0000:00:1d.0: irq 23, io base 0x0000fe00[    3.425351] usb usb2: New USB device found, idVendor=1d6b, idProduct=0001[    3.425353] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1[    3.425355] usb usb2: Product: UHCI Host Controller[    3.425357] usb usb2: Manufacturer: Linux 3.2.57 uhci_hcd[    3.425359] usb usb2: SerialNumber: 0000:00:1d.0[    3.425647] hub 2-0:1.0: USB hub found[    3.425653] hub 2-0:1.0: 2 ports detected[    3.425743] uhci_hcd 0000:00:1d.1: setting latency timer to 64[    3.425746] uhci_hcd 0000:00:1d.1: UHCI Host Controller[    3.425753] uhci_hcd 0000:00:1d.1: new USB bus registered, assigned bus number 3[    3.425790] uhci_hcd 0000:00:1d.1: irq 19, io base 0x0000fd00[    3.425824] usb usb3: New USB device found, idVendor=1d6b, idProduct=0001[    3.425826] usb usb3: New USB device strings: Mfr=3, Product=2, SerialNumber=1[    3.425828] usb usb3: Product: UHCI Host Controller[    3.425830] usb usb3: Manufacturer: Linux 3.2.57 uhci_hcd[    3.425832] usb usb3: SerialNumber: 0000:00:1d.1[    3.425938] hub 3-0:1.0: USB hub found[    3.425942] hub 3-0:1.0: 2 ports detected[    3.426010] uhci_hcd 0000:00:1d.2: setting latency timer to 64[    3.426014] uhci_hcd 0000:00:1d.2: UHCI Host Controller[    3.426020] uhci_hcd 0000:00:1d.2: new USB bus registered, assigned bus number 4[    3.426051] uhci_hcd 0000:00:1d.2: irq 18, io base 0x0000fc00[    3.426082] usb usb4: New USB device found, idVendor=1d6b, idProduct=0001[    3.426085] usb usb4: New USB device strings: Mfr=3, Product=2, SerialNumber=1[    3.426087] usb usb4: Product: UHCI Host Controller[    3.426089] usb usb4: Manufacturer: Linux 3.2.57 uhci_hcd[    3.426091] usb usb4: SerialNumber: 0000:00:1d.2[    3.426198] hub 4-0:1.0: USB hub found[    3.426202] hub 4-0:1.0: 2 ports detected[    3.426273] uhci_hcd 0000:00:1d.3: setting latency timer to 64[    3.426276] uhci_hcd 0000:00:1d.3: UHCI Host Controller[    3.426283] uhci_hcd 0000:00:1d.3: new USB bus registered, assigned bus number 5[    3.426314] uhci_hcd 0000:00:1d.3: irq 16, io base 0x0000fb00[    3.426344] usb usb5: New USB device found, idVendor=1d6b, idProduct=0001[    3.426347] usb usb5: New USB device strings: Mfr=3, Product=2, SerialNumber=1[    3.426349] usb usb5: Product: UHCI Host Controller[    3.426351] usb usb5: Manufacturer: Linux 3.2.57 uhci_hcd[    3.426353] usb usb5: SerialNumber: 0000:00:1d.3[    3.426454] hub 5-0:1.0: USB hub found[    3.426457] hub 5-0:1.0: 2 ports detected

因为当前系统上有多个uhci hcd controller,对每个uhci hcd controller都有相应的输出信息。

在当前系统上可以列出所有的hcd controller信息:

$ tree /sys/bus/usb/devices/sys/bus/usb/devices├── 1-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-0:1.0├── 1-1 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-1├── 1-1:1.0 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0├── 1-1.2 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1.2├── 1-1.2:1.0 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1.2/1-1.2:1.0├── 1-1.2:1.1 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1.2/1-1.2:1.1├── 1-4 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-4├── 1-4:1.0 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1/1-4/1-4:1.0├── 2-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb2/2-0:1.0├── 2-2 -> ../../../devices/pci0000:00/0000:00:1d.0/usb2/2-2├── 2-2:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0├── 3-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.1/usb3/3-0:1.0├── 3-1 -> ../../../devices/pci0000:00/0000:00:1d.1/usb3/3-1├── 3-1:1.0 -> ../../../devices/pci0000:00/0000:00:1d.1/usb3/3-1/3-1:1.0├── 4-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.2/usb4/4-0:1.0├── 5-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.3/usb5/5-0:1.0├── usb1 -> ../../../devices/pci0000:00/0000:00:1d.7/usb1├── usb2 -> ../../../devices/pci0000:00/0000:00:1d.0/usb2├── usb3 -> ../../../devices/pci0000:00/0000:00:1d.1/usb3├── usb4 -> ../../../devices/pci0000:00/0000:00:1d.2/usb4└── usb5 -> ../../../devices/pci0000:00/0000:00:1d.3/usb5

 

加载ata-piix.ko模块,调用piix_init,piix_init调用pci_register_driver(&piix_pci_driver),之后调用piix_pci_driver.probe,即piix_init_one。

输出下面信息:

[    3.426522] ata_piix 0000:00:1f.1: version 2.13

piix_init_one调用pci_set_master,pci_set_master调用pcibios_set_master,pcibios_set_master调用, 输出下面信息:

[    3.426578] ata_piix 0000:00:1f.1: setting latency timer to 64

piix_init_one调用ata_pci_sff_activate_host,ata_pci_sff_activate_host调用ata_host_register,ata_host_register调用ata_scsi_add_hosts,

ata_scsi_add_hosts对每个port调用scsi_add_host,scsi_add_host调用scsi_add_host_with_dma,输出下面信息(因为多次调用,所以多行输出):

[    3.427370] scsi0 : ata_piix[    3.427473] scsi1 : ata_piix

ata_host_register中对每个port输出信息,得到如下内容:

[    3.427936] ata1: PATA max UDMA/100 cmd 0x1f0 ctl 0x3f6 bmdma 0xfa00 irq 14[    3.427939] ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0xfa08 irq 15

 

接着对于新的IDE controller,调用piix_pci_driver.probe,即piix_init_one。

piinx_init_one调用piix_init_sata_map,输出下面信息:

[    3.427974] ata_piix 0000:00:1f.2: MAP [ P0 P2 P1 P3 ]

piix_init_one调用pci_set_master,pci_set_master调用pcibios_set_master,pcibios_set_master调用, 输出下面信息:

[    3.426578] ata_piix 0000:00:1f.1: setting latency timer to 64

下面一行输出是ata2的错误信息(懒得分析是从哪儿产生的):

[    3.428496] ata2: port disabled--ignoring

与前面类似,还有下面的输出:

[    3.428513] scsi2 : ata_piix[    3.428907] scsi3 : ata_piix[    3.429356] ata3: SATA max UDMA/133 cmd 0xf900 ctl 0xf800 bmdma 0xf500 irq 19[    3.429359] ata4: SATA max UDMA/133 cmd 0xf700 ctl 0xf600 bmdma 0xf508 irq 19

 

ata_host_register对每个port调用async_schedule异步执行async_port_probe.

async_port_probe调用ata_port_probe,ata_port_probe调用ata_bus_probe,ata_bus_probe对总线上设备调用ata_dev_configure.

[    3.600351] ata3.00: ATA-8: ST3250318AS, CC38, max UDMA/133[    3.600358] ata3.00: 488397168 sectors, multi 16: LBA48 NCQ (depth 0/32)

ata_bus_probe调用ata_set_mode,ata_set_mode 调用ata_do_set_mode,ata_do_set_mode调用ata_dev_set_mode,输出下面信息:

[    3.616337] ata3.00: configured for UDMA/133

 

前面提到过,在usbcore刚挂载时,创建了一个khubd内核线程,用于检查hub的状态并执行相应的功能,线程执行函数是hub_thread.

hub_thread中调用hub_events, hub_events调用hub_port_init,输出下面信息:

[    3.736020] usb 1-1: new high-speed USB device number 2 using ehci_hcd

 对ata1仍然也有调用async_schedule,虽然它先被调用,但是却执行比ata3还晚,输出下面信息:

[    3.760302] ata1.01: ATAPI: ATAPI   iHDP118   4, GL05, max UDMA/33[    3.776191] ata1.01: configured for UDMA/33

下面两行不知道是哪个函数调用scsi_add_lun产生的:

[    3.778163] scsi 0:0:1:0: CD-ROM            ATAPI    iHDP118   4      GL05 PQ: 0 ANSI: 5[    3.778453] scsi 2:0:0:0: Direct-Access     ATA      ST3250318AS      CC38 PQ: 0 ANSI: 5

 

此时检测到硬盘,会调用sd_probe.sd_probe调用async_schedule异步调用sd_probe_async,sd_probe_async调用sd_revalidate_disk,

sd_revalidate_disk调用sd_read_capacity,输出下面信息:

[    3.783064] sd 2:0:0:0: [sda] 488397168 512-byte logical blocks: (250 GB/232 GiB)

sd_revalidate_disk调用sd_read_write_protect_flag,输出下面信息:

[    3.783126] sd 2:0:0:0: [sda] Write Protect is off
[ 3.783128] sd 2:0:0:0: [sda] Mode Sense: 00 3a 00 00

sd_revalidate_disk调用sd_read_cache_type,输出下面信息:

[    3.783148] sd 2:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesnt support DPO or FUA

 

此时检测到光驱,调用sr_probe,sr_probe调用get_capabilites,输出下面信息:

[    3.785910] sr0: scsi3-mmc drive: 48x/48x cd/rw xa/form2 cdda tray

sr_probe调用register_cdrom,输出下面信息:

[    3.785915] cdrom: Uniform CD-ROM driver Revision: 3.20

sr_probe中输出下面信息:

[    3.786106] sr 0:0:1:0: Attached scsi CD-ROM sr0

 

下面两行输出不知道是从哪个地方调用过去的。

tsc_refine_calibration_work中产生下面输出:

[    3.836020] Refined TSC clocksource calibration: 2510.403 MHz.

clocksource_select中产生下面输出:

[    3.836028] Switching to clocksource tsc

 

下面一行输出信息不知道是如何产生的(应该是在sd_probe_async中产生的?):

[    3.842587]  sda: sda1 sda2 < sda5 sda6 sda7 sda8 > sda3

sd_probe_async中输出下面信息:

[    3.843109] sd 2:0:0:0: [sda] Attached SCSI disk

 

下面两行信息是从sg_add函数产生的(但不知道是从哪个地方调用过去的):

[    3.845469] sr 0:0:1:0: Attached scsi generic sg0 type 5[    3.845545] sd 2:0:0:0: Attached scsi generic sg1 type 0

下面的输出信息和前面类似(khubd检测并输出信息):

[    3.868682] usb 1-1: New USB device found, idVendor=1a40, idProduct=0101[    3.868685] usb 1-1: New USB device strings: Mfr=0, Product=1, SerialNumber=0[    3.868687] usb 1-1: Product: USB 2.0 Hub[    3.868967] hub 1-1:1.0: USB hub found[    3.869062] hub 1-1:1.0: 4 ports detected[    4.092020] usb 1-4: new high-speed USB device number 5 using ehci_hcd[    4.224322] usb 1-4: New USB device found, idVendor=0b1e, idProduct=0006[    4.224328] usb 1-4: New USB device strings: Mfr=0, Product=0, SerialNumber=0[    4.464020] usb 2-2: new low-speed USB device number 2 using uhci_hcd

接着三行信息是电源管理模块相关:

[    4.633397] PM: Starting manual resume from disk[    4.633400] PM: Hibernation image partition 8:8 present[    4.633401] PM: Looking for hibernation image.

检测到罗技光电鼠标:

[    4.639360] usb 2-2: New USB device found, idVendor=046d, idProduct=c05a[    4.639365] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0[    4.639370] usb 2-2: Product: USB Optical Mouse[    4.639373] usb 2-2: Manufacturer: Logitech

 

后面还有一些输出信息,以后有时间在分析具体模块的驱动时再来详细说明。