Claude review: drm/tests: Mark slow tests as slow

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

**Reviewed files:**
- `drivers/gpu/drm/scheduler/tests/tests_basic.c` — two changes
- `drivers/gpu/drm/tests/drm_buddy_test.c` — one change

All three changes are identical in nature: `KUNIT_CASE(...)` → `KUNIT_CASE_SLOW(...)`.

**scheduler/tests/tests_basic.c:**

```c
-	KUNIT_CASE(drm_sched_change_priority),
+	KUNIT_CASE_SLOW(drm_sched_change_priority),
```

```c
-	KUNIT_CASE(drm_sched_test_credits),
+	KUNIT_CASE_SLOW(drm_sched_test_credits),
```

Both are reasonable candidates. `drm_sched_change_priority` uses `usleep_range` polling loops and `drm_sched_test_credits` calls `drm_mock_sched_job_wait_finished(job, HZ)` which waits up to 1 second by design, so it can plausibly cross the threshold.

**tests/drm_buddy_test.c:**

```c
-	KUNIT_CASE(drm_test_buddy_fragmentation_performance),
+	KUNIT_CASE_SLOW(drm_test_buddy_fragmentation_performance),
```

A performance/stress test is a natural candidate for the slow annotation.

**Minor observation:** The commit message says tests "cross the 1s execution time threshold" but doesn't mention which specific tests or on what hardware. This is fine for a patch of this scope, but if reviewers want reproducibility context, it could be worth noting whether these were measured on a particular CI system. This is not a blocker.

**Verdict:** Patch looks good.

Reviewed-by: AI Review <ai@review>

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Generated by Claude Code Patch Reviewer