[igt-dev] [PATCH i-g-t] meson: Disable testplan build by default

[Mauro Carvalho Chehab]

On Wed, 12 Apr 2023 17:18:32 +0300
Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:

> On Wed, Apr 12, 2023 at 02:54:26PM +0200, Mauro Carvalho Chehab wrote:
> > On Wed, 12 Apr 2023 10:33:39 +0300
> > Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:
> >   
> > > On Wed, Apr 12, 2023 at 09:26:29AM +0200, Mauro Carvalho Chehab wrote:  
> > > > On Tue, 11 Apr 2023 14:02:05 +0300
> > > > Ville Syrjala <ville.syrjala at linux.intel.com> wrote:
> > > >   
> > > > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>  
> > > >   
> > > > > No real idea what this "testplan" is and why it lives
> > > > > in igt. Seems to be build some xe documentation, and based
> > > > > on the name is maybe some manager level stuff? Surely
> > > > > this is nothing that matters for normal people (esp. those
> > > > > outside Intel).  
> > > > 
> > > > No. Basically, testplan contains documentation for the tests.
> > > > Currently, it contains 100% of the documentation from Xe tests.
> > > > We may end implementing it for i915 as well.
> > > > 
> > > > There is even a plan to generate testlists like xe-fast-feedback.testlist
> > > > directly from documentation. So, it is important to have the tests properly
> > > > documented, as otherwise they won't be executed by CI in the future.
> > > >   
> > > > > 
> > > > > The main problem here being that it is hideously slow to
> > > > > build, making life miserable for everyone. Flip the
> > > > > default to disabled and let those that need this enable
> > > > > it themselves.  
> > > > 
> > > > Generating documents takes ~150ms. What makes it slow is not the doc
> > > > generation itself, but a validation logic that checks if the test 
> > > > documentation was updated as tests got added/renamed/removed. 
> > > > It currently uses igt_runner, pointing to the documented tests. 
> > > > As right now just Xe tests uses it, it will call the runner with:
> > > > 
> > > > 	$ igt_runner -L -t igt at xe ${builddir}/tests  
> > > 
> > > That is not the slow thing. The slow thing is some python stuff.  
> > 
> > This was part of the slow logic. The other part is to run regular
> > expressions to check test names. This also needed some optimization. 
> > 
> > Just sent a patch series using re.compile() to speed regexes, with
> > a replacement patch for igt_runner.
> > 
> > It could be possible to optimize it even further with multithreading
> > but as it is now taking 500ms to run (against 12 seconds before that on
> > a i7 notebook using python 3.11), it seems good enough to me after the
> > changes.
> > 
> > Patch series sent: https://patchwork.freedesktop.org/series/116379/  
> 
> That is definitely much improved. Thanks.
> 
> Still feels a bit too slow to keep enabled
> during normal developement work though.
> 
> $ time git rebase -x 'ninja -Cbuild' HEAD~10
> 
> -Dtestplan=disabled
> real    0m9,699s
> user    0m26,422s
> sys     0m2,518s
> 
> -Dtestplan=auto
> real    0m46,020s
> user    1m5,102s
> sys     0m4,191s
> 
> At least for me that that would still exceed
> my attention span.
> 
> But seems fast enough for a one off test build 
> before sending out patches/pushing.

I guess we can set sphinx to disable by default. Still, the time to build
from scratch is ~1.30 mins here:

	$ rm -rf build && meson setup build
	$ time ninja -C build
	ninja: Entering directory `build'
	[1330/1330] Generating docs/testplan/xe_tests.html with a custom command
	
	real	1m33.598s
	user	9m5.730s
	sys	1m10.462s

Re-running it with Sphinx disabled after a single file change is fast:

	$ touch tests/xe/xe_compute.c 
	$ time ninja -C build
	ninja: Entering directory `build'
	[5/5] Generating docs/testplan/xe_tests.html with a custom command
	
	real	0m1.746s
	user	0m1.574s
	sys	0m0.171s

Re-running it with Sphinx enabled (and with rst2pdf installed) after a single
file change takes 9 extra seconds here:

	$ touch tests/xe/xe_compute.c 
	$ time ninja -C build
	...
	[9/9] Generating docs/testplan/xe_tests.pdf with a custom command


	real	0m10.545s
	user	0m13.778s
	sys	0m0.724s

So, I'll add this patch at the end of the series:

diff --git a/meson_options.txt b/meson_options.txt
index d4e373d6cfc4..2cb44f20169b 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -26,6 +26,7 @@ option('testplan',
 
 option('sphinx',
        type : 'feature',
+       value : 'disabled',
        description : 'Build testplan documentation using Sphinx')
 
 option('docs',

Please reply with your R-B and/or A-B for me to apply it at the
revision 3 (I'm about to send it).

Regards,
Mauro