[Intel-gfx] [RFC PATCH 00/12] AubCrash

[Oscar Mateo]

On 10/27/2017 11:30 AM, Chris Wilson wrote:
> Quoting Oscar Mateo (2017-10-27 19:01:03)
>> AubCrash is a companion to i915_gpu_error. It gives us the possibility to
>> dump an AUB file that describes the state of the system at the point of
>> the crash (GTTs, contexts, BBs, BOs, etc...). Being an AUB file, it can be
>> used by a number of already existing tools (graphical AUB file browsers,
>> simulators, emulators, etc...) that facilitate debugging (an improvement
>> over the current text-based crash dump).
> Since it is capture everything in progress, but only the kernel side of
> it, why put it in the kernel? Is this absolutely required for
> post-mortem debugging, or should we focus on capturing the death throes
> of userspace much better (an aubcapture flight-data-recorder, plus
> client annotations more akin to apitrace)?
>
> Sell me with the bugzilla references.
> -Chris

An aubcapture flight-data-recorder is the next logical step. Like 
i-g-t's intel_aubdump tool, but at the kernel level, so that it includes 
everything: contexts, WA BBs, virtual GPU addresses, pagetables, etc... 
The trojan horse for that is "drm/i915: Add an AUB file format writer". 
Now you only have to add a couple of debugfs entries (one for start/stop 
the capture, one to retrieve the AUB file as it gets created via 'relay 
channel') and a number of hooks around i915 to capture everything that 
can be interesting.