1.. SPDX-License-Identifier: GPL-2.0+ 2 3========================================= 4Automated testing of the DRM subsystem 5========================================= 6 7Introduction 8============ 9 10Making sure that changes to the core or drivers don't introduce regressions can 11be very time-consuming when lots of different hardware configurations need to 12be tested. Moreover, it isn't practical for each person interested in this 13testing to have to acquire and maintain what can be a considerable amount of 14hardware. 15 16Also, it is desirable for developers to check for regressions in their code by 17themselves, instead of relying on the maintainers to find them and then 18reporting back. 19 20There are facilities in gitlab.freedesktop.org to automatically test Mesa that 21can be used as well for testing the DRM subsystem. This document explains how 22people interested in testing it can use this shared infrastructure to save 23quite some time and effort. 24 25 26Relevant files 27============== 28 29drivers/gpu/drm/ci/gitlab-ci.yml 30-------------------------------- 31 32This is the root configuration file for GitLab CI. Among other less interesting 33bits, it specifies the specific version of the scripts to be used. There are 34some variables that can be modified to change the behavior of the pipeline: 35 36DRM_CI_PROJECT_PATH 37 Repository that contains the Mesa software infrastructure for CI 38 39DRM_CI_COMMIT_SHA 40 A particular revision to use from that repository 41 42UPSTREAM_REPO 43 URL to git repository containing the target branch 44 45TARGET_BRANCH 46 Branch to which this branch is to be merged into 47 48IGT_VERSION 49 Revision of igt-gpu-tools being used, from 50 https://gitlab.freedesktop.org/drm/igt-gpu-tools 51 52drivers/gpu/drm/ci/testlist.txt 53------------------------------- 54 55IGT tests to be run on all drivers (unless mentioned in a driver's \*-skips.txt 56file, see below). 57 58drivers/gpu/drm/ci/${DRIVER_NAME}-${HW_REVISION}-fails.txt 59---------------------------------------------------------- 60 61Lists the known failures for a given driver on a specific hardware revision. 62 63drivers/gpu/drm/ci/${DRIVER_NAME}-${HW_REVISION}-flakes.txt 64----------------------------------------------------------- 65 66Lists the tests that for a given driver on a specific hardware revision are 67known to behave unreliably. These tests won't cause a job to fail regardless of 68the result. They will still be run. 69 70Each new flake entry must be associated with a link to the email reporting the 71bug to the author of the affected driver, the board name or Device Tree name of 72the board, the first kernel version affected, and an approximation of the 73failure rate. 74 75They should be provided under the following format:: 76 77 # Bug Report: $LORE_OR_PATCHWORK_URL 78 # Board Name: broken-board.dtb 79 # Version: 6.6-rc1 80 # Failure Rate: 100 81 flaky-test 82 83drivers/gpu/drm/ci/${DRIVER_NAME}-${HW_REVISION}-skips.txt 84----------------------------------------------------------- 85 86Lists the tests that won't be run for a given driver on a specific hardware 87revision. These are usually tests that interfere with the running of the test 88list due to hanging the machine, causing OOM, taking too long, etc. 89 90 91How to enable automated testing on your tree 92============================================ 93 941. Create a Linux tree in https://gitlab.freedesktop.org/ if you don't have one 95yet 96 972. In your kernel repo's configuration (eg. 98https://gitlab.freedesktop.org/janedoe/linux/-/settings/ci_cd), change the 99CI/CD configuration file from .gitlab-ci.yml to 100drivers/gpu/drm/ci/gitlab-ci.yml. 101 1023. Request to be added to the drm/ci-ok group so that your user has the 103necessary privileges to run the CI on https://gitlab.freedesktop.org/drm/ci-ok 104 1054. Next time you push to this repository, you will see a CI pipeline being 106created (eg. https://gitlab.freedesktop.org/janedoe/linux/-/pipelines) 107 1085. The various jobs will be run and when the pipeline is finished, all jobs 109should be green unless a regression has been found. 110 111 112How to update test expectations 113=============================== 114 115If your changes to the code fix any tests, you will have to remove one or more 116lines from one or more of the files in 117drivers/gpu/drm/ci/${DRIVER_NAME}_*_fails.txt, for each of the test platforms 118affected by the change. 119 120 121How to expand coverage 122====================== 123 124If your code changes make it possible to run more tests (by solving reliability 125issues, for example), you can remove tests from the flakes and/or skips lists, 126and then the expected results if there are any known failures. 127 128If there is a need for updating the version of IGT being used (maybe you have 129added more tests to it), update the IGT_VERSION variable at the top of the 130gitlab-ci.yml file. 131 132 133How to test your changes to the scripts 134======================================= 135 136For testing changes to the scripts in the drm-ci repo, change the 137DRM_CI_PROJECT_PATH and DRM_CI_COMMIT_SHA variables in 138drivers/gpu/drm/ci/gitlab-ci.yml to match your fork of the project (eg. 139janedoe/drm-ci). This fork needs to be in https://gitlab.freedesktop.org/. 140 141 142How to incorporate external fixes in your testing 143================================================= 144 145Often, regressions in other trees will prevent testing changes local to the 146tree under test. These fixes will be automatically merged in during the build 147jobs from a branch in the target tree that is named as 148${TARGET_BRANCH}-external-fixes. 149 150If the pipeline is not in a merge request and a branch with the same name 151exists in the local tree, commits from that branch will be merged in as well. 152 153 154How to deal with automated testing labs that may be down 155======================================================== 156 157If a hardware farm is down and thus causing pipelines to fail that would 158otherwise pass, one can disable all jobs that would be submitted to that farm 159by editing the file at 160https://gitlab.freedesktop.org/gfx-ci/lab-status/-/blob/main/lab-status.yml. 161