[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH V2 07/33] xen/arm: Create a hierarchical device tree



On 05/08/2013 02:41 PM, Ian Campbell wrote:

> On Wed, 2013-05-08 at 14:34 +0100, Julien Grall wrote:
>>> Which only leaves ones which are both? How many are these? I'm inclined
>>> towards suggesting that if they are debug prints which are disabled by
>>> default and require a recompile to enable then the person doing the
>>> debugging can select whether they care about early or late messages by 
>>> #define-ing DEBUG or EARLY_DEBUG or both as required.
>>
>> We can't choose at compile time. Early printk function is in init code
>> section. So at the end of boot the function will disappear.
> 
> Oh, right.
> 
> Perhaps something could be conditional on system_state =
> SYS_STATE_active, this happens not long before we discard the initial
> sections.


I think it's too late. If we use early_printk until this stage, we will
lose some usefull debug when early printk is disabled (ie most of the time).

How about adding the missing system_state = SYS_STATE_boot just after
console_init_preirq? Early printk will only be used when system_state ==
SYS_STATE_early_boot.

>> Device tree function could be called after the end of the boot. For the
>> moment it's not the case.
>>
>> The best solution would be: early_printk is directly handled in console
>> as linux does.
> 
> That does sound best.


I will send a patch later for this.

-- 
Julien


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.