[Intel-gfx] [PATCH 6/9] drm: kselftest for drm_mm and eviction

[Chris Wilson]

Check that we add arbitrary blocks to the eviction scanner in order to
find the first minimal hole that matches our request.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/drm_mm_selftests.h |   1 +
 drivers/gpu/drm/test-drm_mm.c      | 167 +++++++++++++++++++++++++++++++++++++
 2 files changed, 168 insertions(+)

diff --git a/drivers/gpu/drm/drm_mm_selftests.h b/drivers/gpu/drm/drm_mm_selftests.h
index 591d34aa233a..a3ee623b5f59 100644
--- a/drivers/gpu/drm/drm_mm_selftests.h
+++ b/drivers/gpu/drm/drm_mm_selftests.h
@@ -5,6 +5,7 @@
  *
  * Tests are executed in reverse order by igt/drm_mm
  */
+selftest(evict, igt_evict)
 selftest(align64, igt_align64)
 selftest(align32, igt_align32)
 selftest(align, igt_align)
diff --git a/drivers/gpu/drm/test-drm_mm.c b/drivers/gpu/drm/test-drm_mm.c
index 8cdcde580da3..ab9ddfba5cf5 100644
--- a/drivers/gpu/drm/test-drm_mm.c
+++ b/drivers/gpu/drm/test-drm_mm.c
@@ -775,6 +775,173 @@ static int igt_align64(void *ignored)
 	return igt_align_pot(64);
 }
 
+static int igt_evict(void *ignored)
+{
+	const int size = 8192;
+	struct drm_mm mm;
+	struct evict_node {
+		struct drm_mm_node node;
+		struct list_head link;
+	} *nodes;
+	struct drm_mm_node *node, *next;
+	int *order, n, m;
+	int ret;
+
+	ret = -ENOMEM;
+	nodes = vzalloc(size * sizeof(*nodes));
+	if (!nodes)
+		goto err;
+
+	order = random_order(size);
+	if (!order)
+		goto err_nodes;
+
+	ret = -EINVAL;
+	drm_mm_init(&mm, 0, size);
+	for (n = 0; n < size; n++) {
+		int err;
+
+		err = drm_mm_insert_node(&mm, &nodes[n].node, 1, 0,
+					 DRM_MM_SEARCH_DEFAULT);
+		if (err) {
+			pr_err("insert failed, step %d\n", n);
+			ret = err;
+			goto out;
+		}
+	}
+
+	for (n = 1; n < size; n <<= 1) {
+		const int nsize = size / 2;
+		LIST_HEAD(evict_list);
+		struct evict_node *e, *en;
+		struct drm_mm_node tmp;
+		bool found = false;
+		int err;
+
+		drm_mm_init_scan(&mm, nsize, n, 0);
+		for (m = 0; m < size; m++) {
+			e = &nodes[order[m]];
+			list_add(&e->link, &evict_list);
+			if (drm_mm_scan_add_block(&e->node)) {
+				found = true;
+				break;
+			}
+		}
+		if (!found) {
+			pr_err("Failed to fail eviction: size=%d, align=%d\n",
+			       nsize, n);
+			goto out;
+		}
+
+		list_for_each_entry_safe(e, en, &evict_list, link) {
+			if (!drm_mm_scan_remove_block(&e->node))
+				list_del(&e->link);
+		}
+
+		list_for_each_entry(e, &evict_list, link)
+			drm_mm_remove_node(&e->node);
+
+		memset(&tmp, 0, sizeof(tmp));
+		err = drm_mm_insert_node(&mm, &tmp, nsize, n,
+					 DRM_MM_SEARCH_DEFAULT);
+		if (err) {
+			pr_err("Failed to insert into eviction hole: size=%d, align=%d\n",
+			       nsize, n);
+			goto out;
+		}
+
+		if (tmp.start % n || tmp.size != nsize || tmp.hole_follows) {
+			pr_err("Inserted did not fill the eviction hole: size=%lld [%d], align=%d, start=%llx, hole-follows?=%d\n",
+			       tmp.size, nsize, n, tmp.start, tmp.hole_follows);
+
+			drm_mm_remove_node(&tmp);
+			goto out;
+		}
+
+		drm_mm_remove_node(&tmp);
+		list_for_each_entry(e, &evict_list, link) {
+			err = drm_mm_reserve_node(&mm, &e->node);
+			if (err) {
+				pr_err("Failed to reinsert node after eviction: start=%llx\n",
+				       e->node.start);
+				ret = err;
+				goto out;
+			}
+		}
+	}
+
+	for_each_prime(n, size) {
+		LIST_HEAD(evict_list);
+		struct evict_node *e, *en;
+		struct drm_mm_node tmp;
+		int nsize = (size - n + 1) / 2;
+		bool found = false;
+		int err;
+
+		drm_mm_init_scan(&mm, nsize, n, 0);
+		for (m = 0; m < size; m++) {
+			e = &nodes[order[m]];
+			list_add(&e->link, &evict_list);
+			if (drm_mm_scan_add_block(&e->node)) {
+				found = true;
+				break;
+			}
+		}
+		if (!found) {
+			pr_err("Failed to fail eviction: size=%d, align=%d\n",
+			       nsize, n);
+			goto out;
+		}
+
+		list_for_each_entry_safe(e, en, &evict_list, link) {
+			if (!drm_mm_scan_remove_block(&e->node))
+				list_del(&e->link);
+		}
+
+		list_for_each_entry(e, &evict_list, link)
+			drm_mm_remove_node(&e->node);
+
+		memset(&tmp, 0, sizeof(tmp));
+		err = drm_mm_insert_node(&mm, &tmp, nsize, n,
+					 DRM_MM_SEARCH_DEFAULT);
+		if (err) {
+			pr_err("Failed to insert into eviction hole: size=%d, align=%d\n",
+			       nsize, n);
+			goto out;
+		}
+
+		if (tmp.start % n || tmp.size != nsize || tmp.hole_follows) {
+			pr_err("Inserted did not fill the eviction hole: size=%lld [%d], align=%d, start=%llx, hole-follows?=%d\n",
+			       tmp.size, nsize, n, tmp.start, tmp.hole_follows);
+
+			drm_mm_remove_node(&tmp);
+			goto out;
+		}
+
+		drm_mm_remove_node(&tmp);
+		list_for_each_entry(e, &evict_list, link) {
+			err = drm_mm_reserve_node(&mm, &e->node);
+			if (err) {
+				pr_err("Failed to reinsert node after eviction: start=%llx\n",
+				       e->node.start);
+				ret = err;
+				goto out;
+			}
+		}
+	}
+
+	ret = 0;
+out:
+	list_for_each_entry_safe(node, next, &mm.head_node.node_list, node_list)
+		drm_mm_remove_node(node);
+	drm_mm_takedown(&mm);
+	kfree(order);
+err_nodes:
+	vfree(nodes);
+err:
+	return ret;
+}
+
 #include "drm_selftest.c"
 
 static int __init test_drm_mm_init(void)
-- 
2.11.0