testing drm-next 4.6 on i915 broadwell

[inti.glez.herrera]

Hello,

My current laptop features the i915 Broadwell microarchitecture. I was
trying to use FreeBSD when I realized that the graphic support is
limited. I am interested on actively contributing to the development
(although unfortunately, so far my knowledge is limited). After
cloning freebsd-base-graphcis  (branch drm-next-4.6), I can finally
load the device driver and run Xorg. However, there are some problems:

- The response time becomes really slow.
- Typing a simple command in the console can take 20 seconds.
- The mouse is also moving slow
- Executing a simple startx implies a reset because it slowdown the system
- Even a simple xclock is a problem

I was trying to identify where is the issue and my plan was using
dtrace. Right now I can use it to collect kernel stack traces, but
instead of the name of function, the output is only showing the
addresses.

My question is: do  I need to compile the kernel with some special
flags to support symbols in dtrace ?

A secondary question : do you recommend another profiler (or tool) to
debug this kind of problem ?

Some basic information: I am using the generic configuration and I
updated a bunch of ports using freebsd-ports-graphics.

- Inti