Bug 103762

Summary: [swr] piglit ext_transform_feedback-immediate-reuse-uniform-buffer has a ~5% pass rate
Product: Mesa Reporter: Andrés Gómez García <agomez>
Component: Drivers/Gallium/swrAssignee: Bruce Cherniak <bruce.cherniak>
Status: RESOLVED MOVED QA Contact: mesa-dev
Severity: normal    
Priority: medium    
Version: 17.2   
Hardware: Other   
OS: All   
See Also: https://bugs.freedesktop.org/show_bug.cgi?id=90081
Whiteboard:
i915 platform: i915 features:

Description Andrés Gómez García 2017-11-15 14:07:40 UTC
When running the complete "all" profile in piglit against mesa's swr driver, ext_transform_feedback-immediate-reuse-uniform-buffer most of the time fails, but not always.

It seems its pass rate is ~5%.

AFAIK, this is not new for 17.2.x not a recent regression.

A typical piglit report is as follows, although varies from failed run to run:


Detail      |   Value
------------+---------------
Returncode  |   1
------------+---------------
Time        |   0:00:00.211612
------------+---------------
Stdout      | Probe color at (224,0)
            |   Expected: 223 31 223
            |   Observed: 0 0 0
            | Probe color at (240,0)
            |   Expected: 239 15 239
            |   Observed: 0 0 0
------------+---------------
Stderr      | WR detected AVX2 
            | vert shader  0x7f492c287000
            | frag shader  0x7f492c285000
            | so shader    0x7f492c283000
            | fetch shader 0x7f492c281000
            | fetch shader 0x7f492c27f000
            | SWR destroy screen!
------------+---------------
Environment | PIGLIT_PLATFORM="mixed_glx_egl" PIGLIT_SOURCE_DIR="/home/local/piglit"
------------+---------------
Command     | /home/local/piglit/bin/ext_transform_feedback-immediate-reuse-uniform-buffer -auto -fbo
------------+---------------
dmesg	    |
----------------------------

Environment is an Ubuntu Xenial with custom LLVM packages installed and locally compiled mesa and mesa dependencies. If needed, I can provide a docker image with which to test.
Comment 1 Andrés Gómez García 2017-11-15 14:09:18 UTC
bug 90081 could be related (?)
Comment 2 Bruce Cherniak 2017-11-30 17:16:42 UTC
Ilia had mentioned many moons ago that this fails when SWR is multithreaded, but with KNOB_SINGLE_THREADED=1 it passes.  I had completely forgotten about his sage advice, but this gives me some ideas.
Comment 3 GitLab Migration User 2019-09-18 18:24:17 UTC
-- GitLab Migration Automatic Message --

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