[Intel-gfx] [PATCH v5 06/10] drm/i915/guc: Update GuC's log-buffer-state access for error capture.

[Teres Alexis, Alan Previn]

As per the rev 5 CI results between this patch and patch7, i have introduced a lockdep splat bug, i shall fix that in
the next rev.

...alan

On Wed, 2022-01-26 at 02:48 -0800, Alan Previn wrote:
> GuC log buffer regions for debug-log-events, crash-dumps and
> error-state-capture are all a single bo allocation that includes
> the guc_log_buffer_state structures.
> 
> Since the error-capture region is accessed with high priority at non-
> deterministic times (as part of gpu coredump) while the debug-log-event
> region is populated and accessed with different priorities, timings and
> consumers, let's split out separate locks for buffer-state accesses
> of each region.
> 
> Also, ensure a global mapping is made up front for the entire bo
> throughout GuC operation so that dynamic mapping and unmapping isn't
> required for error capture log access if relay-logging isn't running.
> 
> Additionally, while here, make some readibility improvements:
> 1. change previous function names with "capture_logs" to
>    "copy_debug_logs" to help make the distinction clearer.
> 2. Update the guc log region mapping comments to order them
>    according to the enum definition as per the GuC interface.
>