Re: [PATCH v4 0/9] add xenalyze to staging

[George Dunlap <george.dunlap@eu.citrix.com>]

On 06/09/2015 12:31 PM, Julien Grall wrote:
> Hi Olaf,
> 
> On 09/06/2015 06:18, Olaf Hering wrote:
>> On Wed, Jun 03, Julien Grall wrote:
>>
>>> xentrace is not working as we don't have the infrastructure for ARM
>>> in Xen.
>>
>> Why is that? After a very quick look __trace_var is available
>> unconditionally.
> 
> Multiple reasons, the shared page for trace is not correctly exposed,
> __trace_var/__trace_hypercall is not even used on ARM. I may miss some
> other bugs that I didn't spot while looking to the code.

Code in xen/common will generate traces (e.g., the scheduling code), so
useful traces are already in place for ARM, even if no arm-specific code
has trace points yet.

> So I don't think we should build a non-working binary until someone
> fixes the various problem of the trace system on ARM.

If the shared page really doesn't work, then yes, we should probably not
build it on ARM for the release.

Would it be very difficult to get working?

 -George