Changes in tests_scheduler.c

f412fe573b3c78fdcf351e282a3c488bb073846b - drm/sched: Fix clang build warning in kunit tests

Fri, 22 May 2026 11:01:29 +0200

drm/sched: Fix clang build warning in kunit testsInitializing compile time constant struct or arrays from another suchvariable is a gcc extension, while clang strictly requires a compile timeconstant literal.As reported by LKP:>> drivers/gpu/drm/scheduler/tests/tests_scheduler.c:675:10: error: initializer element is not a compile-time constant drm_sched_scheduler_two_clients_attr), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/kunit/test.h:224:13: note: expanded from macro 'KUNIT_CASE_PARAM_ATTR' .attr = attributes, .module_name = KBUILD_MODNAME} ^~~~~~~~~~ 1 error generated.vim +675 drivers/gpu/drm/scheduler/tests/tests_scheduler.c 671 672 static struct kunit_case drm_sched_scheduler_two_clients_tests[] = { 673 KUNIT_CASE_PARAM_ATTR(drm_sched_scheduler_two_clients_test, 674 drm_sched_scheduler_two_clients_gen_params, > 675 drm_sched_scheduler_two_clients_attr), 676 {} 677 }; 678Fix it by using a compound literal as other tests do.Signed-off-by: Tvrtko Ursulin Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202605220312.Pu7UO05u-lkp@intel.com/Fixes: 97ef806a5314 ("drm/sched: Add some scheduling quality unit tests")Cc: Philipp Stanner Acked-by: Philipp Stanner Signed-off-by: Tvrtko Ursulin Link: https://lore.kernel.org/r/20260522090129.9385-1-tvrtko.ursulin@igalia.com List of files: /linux/drivers/gpu/drm/scheduler/tests/tests_scheduler.c

df5ff8b62a47bb6a378c81ce8aff267f6e5c9e3f - drm/sched: Add some more scheduling quality unit tests

Fri, 17 Apr 2026 12:37:20 +0200

drm/sched: Add some more scheduling quality unit testsThis time round we explore the rate of submitted job queue processingwith multiple identical parallel clients.Example test output:3 clients: t cycle: min avg max : ... + 0ms 0 0 0 : 0 0 0 + 102ms 2 2 2 : 2 2 2 + 208ms 5 6 6 : 6 5 5 + 310ms 8 9 9 : 9 9 8... + 2616ms 82 83 83 : 83 83 82 + 2717ms 83 83 83 : 83 83 83 avg_max_min_delta(x100)=60Every 100ms for the duration of the test it logs how many jobs eachclient had completed, prefixed by minimum, average and maximum numbers.When finished overall average delta between max and min is output as arough indicator to scheduling fairness.Signed-off-by: Tvrtko Ursulin Cc: Christian König Cc: Danilo Krummrich Cc: Matthew Brost Cc: Philipp Stanner Cc: Pierre-Eric Pelloux-Prayer Acked-by: Christian König Acked-by: Danilo Krummrich Tested-by: Vitaly Prosyak Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20260417103744.76020-6-tvrtko.ursulin@igalia.com List of files: /linux/drivers/gpu/drm/scheduler/tests/tests_scheduler.c

97ef806a53146837f6ca84a1b36763fb3bb67eaa - drm/sched: Add some scheduling quality unit tests

Fri, 17 Apr 2026 12:37:19 +0200

drm/sched: Add some scheduling quality unit testsTo make evaluating different scheduling policies easier (no need forexternal benchmarks) and perfectly repeatable, lets add some syntheticworkloads built upon mock scheduler unit test infrastructure.Focus is on two parallel clients (two threads) submitting different jobpatterns and logging their progress and some overall metrics. This isrepeated for both scheduler credit limit 1 and 2.Example test output: Normal and low: pct1 cps1 qd1; pct2 cps2 qd2 + 0ms: 0 0 0; 0 0 0 + 104ms: 100 1240 112; 100 1240 125 + 209ms: 100 0 99; 100 0 125 + 313ms: 100 0 86; 100 0 125 + 419ms: 100 0 73; 100 0 125 + 524ms: 100 0 60; 100 0 125 + 628ms: 100 0 47; 100 0 125 + 731ms: 100 0 34; 100 0 125 + 836ms: 100 0 21; 100 0 125 + 939ms: 100 0 8; 100 0 125 + 1043ms: ; 100 0 120 + 1147ms: ; 100 0 107 + 1252ms: ; 100 0 94 + 1355ms: ; 100 0 81 + 1459ms: ; 100 0 68 + 1563ms: ; 100 0 55 + 1667ms: ; 100 0 42 + 1771ms: ; 100 0 29 + 1875ms: ; 100 0 16 + 1979ms: ; 100 0 3 0: prio=normal sync=0 elapsed_ms=1015ms (ideal_ms=1000ms) cycle_time(min,avg,max)=134,222,978 us latency_time(min,avg,max)=134,222,978us 1: prio=low sync=0 elapsed_ms=2009ms (ideal_ms=1000ms) cycle_time(min,avg,max)=134,215,806 us latency_time(min,avg,max)=134,215,806 usThere we have two clients represented in the two respective columns, withtheir progress logged roughly every 100 milliseconds. The metrics are: - pct - Percentage progress of the job submit part - cps - Cycles per second - qd - Queue depth - number of submitted unfinished jobsThe cycles per second metric is inherent to the fact that workloadpatterns are a data driven cycling sequence of: - Submit 1..N jobs - Wait for Nth job to finish (optional) - Sleep (optional) - Repeat from startIn this particular example we have a normal priority and a low priorityclient both spamming the scheduler with 8ms jobs with no sync and nosleeping. Hence they build very deep queues and we can see how the lowpriority client is completely starved until the normal finishes.Note that the PCT and CPS metrics are irrelevant for "unsync" clientssince they manage to complete all of their cycles instantaneously.A different example would be: Heavy and interactive: pct1 cps1 qd1; pct2 cps2 qd2 + 0ms: 0 0 0; 0 0 0 + 106ms: 5 40 3; 5 40 0 + 209ms: 9 40 0; 9 40 0 + 314ms: 14 50 3; 14 50 0 + 417ms: 18 40 0; 18 40 0 + 522ms: 23 50 3; 23 50 0 + 625ms: 27 40 0; 27 40 1 + 729ms: 32 50 0; 32 50 0 + 833ms: 36 40 1; 36 40 0 + 937ms: 40 40 0; 40 40 0 + 1041ms: 45 50 0; 45 50 0 + 1146ms: 49 40 1; 49 40 1 + 1249ms: 54 50 0; 54 50 0 + 1353ms: 58 40 1; 58 40 0 + 1457ms: 62 40 0; 62 40 1 + 1561ms: 67 50 0; 67 50 0 + 1665ms: 71 40 1; 71 40 0 + 1772ms: 76 50 0; 76 50 0 + 1877ms: 80 40 1; 80 40 0 + 1981ms: 84 40 0; 84 40 0 + 2085ms: 89 50 0; 89 50 0 + 2189ms: 93 40 1; 93 40 0 + 2293ms: 97 40 0; 97 40 1In this case client one is submitting 3x 2.5ms jobs, waiting for the 3rdand then sleeping for 2.5ms (in effect causing 75% GPU load, minus theoverheads). Second client is submitting 1ms jobs, waiting for each tofinish and sleeping for 9ms (effective 10% GPU load). Here we can seethe PCT and CPS reflecting real progress.Signed-off-by: Tvrtko Ursulin Cc: Christian König Cc: Danilo Krummrich Cc: Matthew Brost Cc: Philipp Stanner Cc: Pierre-Eric Pelloux-Prayer Acked-by: Christian König Acked-by: Danilo Krummrich Tested-by: Vitaly Prosyak Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20260417103744.76020-5-tvrtko.ursulin@igalia.com List of files: /linux/drivers/gpu/drm/scheduler/tests/tests_scheduler.c