On 05/01/2022 13:18, Jani Nikula wrote:
On Wed, 05 Jan 2022, Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote:
On 05/01/2022 10:32, Jani Nikula wrote:
On Wed, 05 Jan 2022, Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote:
On 05/01/2022 10:05, Jani Nikula wrote:
Follow the usual naming convention.
But intel_uncore_ prefix usually means functions takes intel_uncore as
the first argument.
Maybe solution here is that i915_reg_read_ioctl does not belong in
intel_uncore.c, it being the UAPI layer thing? I guess arguments could
be made for either way.
My position is that the function and file prefixes go hand in
hand. You'll always know where to place a function, and you'll always
know where the function is to be found.
If you can *also* make the context argument follow the pattern, it's
obviously better, and indicates the division to files is working out
nicely. However, in a lot of cases you'll need to pass struct
drm_i915_private or similar as the first parameter to e.g. init
functions. It can't be the rigid rule.
I'm fine with moving the entire function somewhere else, as long as the
declaration is not in i915_drv.h. There's no longer a i915_drv.c, and
i915_drv.h should not have function declarations at all.
Yes I agree it cannot be a rigid rule. I just that it feels
intel_uncore.[hc] is too low level to me to hold an ioctl
implementation, and header actually feels wrong to have the declaration.
Not least it is about _one_ of the uncores, while the ioctl is not
operating on that level, albeit undefined at the moment how exactly it
would work for multi-tile.
Would it be too early, or unwarranted at this point, to maybe consider
adding i915_ioctls.[hc]?
Then the conversation would be about putting together a ton of unrelated
functions where the only thing in common is that they're an ioctl
implementation. Arguably many of them would have less in common than the
reg read ioctl has with uncore!
I imagined it as a place for ioctls which don't fit anywhere else, like
it this case it is not a family of ioctls but and odd one out. So yes,
first "problem" would be there is only one to put there and no line of
sight for others.
And when is it okay to put an ioctl in the i915_ioctls.c file and when
is it warranted to put it somewhere else? It's just a different set of
problems.
When it does not fit anywhere else?
I like the i915_ prefix of ioctls for consistency.. i915_getparam_ioctl,
i915_query_ioctl, i915_perf_..., i915_gem_....
The display ioctls have intel_ prefix anyway. It's the _ioctl suffix
that we use.
Again, my main driver here is cleaning up i915_drv.h. I can shove the
reg read ioctl somewhere other than intel_uncore.[ch] too. But as it
stands, the only alternative that seems better than intel_uncore.[ch] at
the moment is adding a dedicated file for a 60-line function.
I understand your motivation and I wouldn't nack your efforts, but I
also cannot yet make myself ack it. Is 60 lines so bad? Lets see..
$ find . -name "*.c" -print0 | xargs -0 wc -l | sort -nr
...
59 ./selftests/mock_request.c
59 ./gt/uc/intel_uc_debugfs.c
59 ./gem/i915_gemfs.c
52 ./selftests/igt_mmap.c
51 ./selftests/igt_reset.c
49 ./selftests/mock_uncore.c
47 ./selftests/igt_atomic.c
36 ./gt/uc/intel_huc_debugfs.c
36 ./gt/intel_gt_engines_debugfs.c
35 ./selftests/igt_flush_test.c
34 ./selftests/librapl.c
34 ./gvt/trace_points.c
29 ./gt/selftests/mock_timeline.c
27 ./gt/selftest_engine.c
26 ./gt/uc/intel_huc_fw.c
15 ./i915_config.c
14 ./i915_trace_points.c
9 ./display/intel_display_trace.c
So kind of meh, wouldn't be first. I'd add a dedicated file just for the
benefit of being able to legitimately keep the i915_reg_read_ioctl name.
Come multi-tile it may get company. Even though at the moment I am not
aware anyone is trying to add multi-tile aware reg read, but I expect
there will be need as long as need for the existing one exists.
Regards,
Tvrtko
