Re: [PATCH] common: remove USE_EXTERNAL

[Dave Chinner <david@fromorbit.com>]

On Mon, Apr 14, 2025 at 07:42:05AM +0200, Christoph Hellwig wrote:
> The USE_EXTERNAL variable indicates that dedicated log or RT devices are
> in use for the scratch and possibly test device.  It gets automatically
> set when needed

No it isn't - it's explicitly controlled by config file parsing
and/or config env variable setup.

> and generally does not provide any benefit over simply
> testing the SCRATCH_LOGDEV and SCRATCH_RTDEV variables.
> 
> Remove it and replace that test with test for SCRATCH_LOGDEV and
> SCRATCH_RTDEV, using the more readable if-based syntaxt for all tests
> touched by this change.

This breaks the way I've set up check-parallel devices. I always
create the external devices, and then trigger where they are in use
by config sections that define USE_EXTERNAL.

Hence changing all this code to check if SCRATCH_LOGDEV and/or
SCRATCH_RTDEV are defined instead of gating them on USE_EXTERNAL
breaks any test environment that has those devices defined but does
not set USE_EXTERNAL....

-Dave.
-- 
Dave Chinner
david@fromorbit.com