Dear Greg,
Thank you for the quick reply.
Am 05.05.21 um 10:11 schrieb Greg Kroah-Hartman:
On Wed, May 05, 2021 at 09:57:44AM +0200, Paul Menzel wrote:
On an Asus F2A85-M PRO, BIOS 6601 11/25/2014, with an ASM1042 SuperSpeed USB
Host Controller [1b21:1042], and the xHCI drivers built as modules
CONFIG_USB_XHCI_PCI=m
CONFIG_USB_XHCI_HCD=m
`quirk_usb_handoff_xhci` takes 60 ms, which is 15 % of the time to reaching
`run_init_process()`. I addded some prints, showing the f
[ 0.308841] pci 0000:03:00.0: PCI->APIC IRQ transform: INT A -> IRQ 17
[ 0.369858] pci 0000:03:00.0: handshake done with timeout = 0
[ 0.369862] pci 0000:03:00.0: hc_init reached
[ 0.369865] pci 0000:03:00.0: second handshake done
[ 0.369869] pci 0000:03:00.0: third handshake done
[ 0.369909] pci 0000:03:00.0: quirk_usb_early_handoff+0x0/0x670 took 59661 usecs
[…]
[ 0.415223] Run /lib/systemd/systemd as init process
Is there a way to optimize this, or move it out “the hot path”?
That's the hardware taking so long, all that function does is make some
PCI calls to the device.
In your experience, do most devices take that long?
If the driver is built as a module, there should not be any "hot
path" here as the module is loaded async when the device is
discovered, right?
obj-$(CONFIG_USB_PCI) += pci-quirks.o
So all quirks are run independently of the USB “variant” (UHCI, OHCI,
EHCI, xHCI).
Indeed, this driver is built into the Linux kernel.
$ grep USB_PCI .config
CONFIG_USB_PCI=y
So, should `pci-quirks.c` be split up to have more fine grained control?
What is waiting for this module to load in order to cause your init to
stall? Perhaps fix your initramfs logic or build the driver into the
kernel itself to take it off of this "load all the modules and wait"
path?
Sorry, for causing some confusion. But as written above, this all
happens before the initrd is involved.
Kind regards,
Paul
