drm: kselftest for drm_mm and top-down allocation

Check that if we request top-down allocation from drm_mm_insert_node()
we receive the next available hole from the top.

v2: Flip sign on conditional assert.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-17-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/selftests/drm_mm_selftests.h b/drivers/gpu/drm/selftests/drm_mm_selftests.h
index 965aca65c1608116da5f9e0f51eae889d8cbc0f6..cd508e3d65380adfcaa063ca2adf4b0f93b71ab5 100644 (file)
--- a/drivers/gpu/drm/selftests/drm_mm_selftests.h
+++ b/drivers/gpu/drm/selftests/drm_mm_selftests.h
@@ -17,3 +17,4 @@ selftest(align32, igt_align32)
 selftest(align64, igt_align64)
 selftest(evict, igt_evict)
 selftest(evict_range, igt_evict_range)
+selftest(topdown, igt_topdown)

diff --git a/drivers/gpu/drm/selftests/test-drm_mm.c b/drivers/gpu/drm/selftests/test-drm_mm.c
index d49115186967a1260ac1db48645ac7f2832c72e2..d3d4e4f390420dfa603819f9ea5488750433e0c8 100644 (file)
--- a/drivers/gpu/drm/selftests/test-drm_mm.c
+++ b/drivers/gpu/drm/selftests/test-drm_mm.c
@@ -1552,6 +1552,125 @@ err:
        return ret;
 }
 
+static unsigned int node_index(const struct drm_mm_node *node)
+{
+       return div64_u64(node->start, node->size);
+}
+
+static int igt_topdown(void *ignored)
+{
+       const struct insert_mode *topdown = &insert_modes[TOPDOWN];
+       DRM_RND_STATE(prng, random_seed);
+       const unsigned int count = 8192;
+       unsigned int size;
+       unsigned long *bitmap = NULL;
+       struct drm_mm mm;
+       struct drm_mm_node *nodes, *node, *next;
+       unsigned int *order, n, m, o = 0;
+       int ret;
+
+       /* When allocating top-down, we expect to be returned a node
+        * from a suitable hole at the top of the drm_mm. We check that
+        * the returned node does match the highest available slot.
+        */
+
+       ret = -ENOMEM;
+       nodes = vzalloc(count * sizeof(*nodes));
+       if (!nodes)
+               goto err;
+
+       bitmap = kzalloc(count / BITS_PER_LONG * sizeof(unsigned long),
+                        GFP_TEMPORARY);
+       if (!bitmap)
+               goto err_nodes;
+
+       order = drm_random_order(count, &prng);
+       if (!order)
+               goto err_bitmap;
+
+       ret = -EINVAL;
+       for (size = 1; size <= 64; size <<= 1) {
+               drm_mm_init(&mm, 0, size*count);
+               for (n = 0; n < count; n++) {
+                       if (!expect_insert(&mm, &nodes[n],
+                                          size, 0, n,
+                                          topdown)) {
+                               pr_err("insert failed, size %u step %d\n", size, n);
+                               goto out;
+                       }
+
+                       if (nodes[n].hole_follows) {
+                               pr_err("hole after topdown insert %d, start=%llx\n, size=%u",
+                                      n, nodes[n].start, size);
+                               goto out;
+                       }
+
+                       if (!assert_one_hole(&mm, 0, size*(count - n - 1)))
+                               goto out;
+               }
+
+               if (!assert_continuous(&mm, size))
+                       goto out;
+
+               drm_random_reorder(order, count, &prng);
+               for_each_prime_number_from(n, 1, min(count, max_prime)) {
+                       for (m = 0; m < n; m++) {
+                               node = &nodes[order[(o + m) % count]];
+                               drm_mm_remove_node(node);
+                               __set_bit(node_index(node), bitmap);
+                       }
+
+                       for (m = 0; m < n; m++) {
+                               unsigned int last;
+
+                               node = &nodes[order[(o + m) % count]];
+                               if (!expect_insert(&mm, node,
+                                                  size, 0, 0,
+                                                  topdown)) {
+                                       pr_err("insert failed, step %d/%d\n", m, n);
+                                       goto out;
+                               }
+
+                               if (node->hole_follows) {
+                                       pr_err("hole after topdown insert %d/%d, start=%llx\n",
+                                              m, n, node->start);
+                                       goto out;
+                               }
+
+                               last = find_last_bit(bitmap, count);
+                               if (node_index(node) != last) {
+                                       pr_err("node %d/%d, size %d, not inserted into upmost hole, expected %d, found %d\n",
+                                              m, n, size, last, node_index(node));
+                                       goto out;
+                               }
+
+                               __clear_bit(last, bitmap);
+                       }
+
+                       DRM_MM_BUG_ON(find_first_bit(bitmap, count) != count);
+
+                       o += n;
+               }
+
+               drm_mm_for_each_node_safe(node, next, &mm)
+                       drm_mm_remove_node(node);
+               DRM_MM_BUG_ON(!drm_mm_clean(&mm));
+       }
+
+       ret = 0;
+out:
+       drm_mm_for_each_node_safe(node, next, &mm)
+               drm_mm_remove_node(node);
+       drm_mm_takedown(&mm);
+       kfree(order);
+err_bitmap:
+       kfree(bitmap);
+err_nodes:
+       vfree(nodes);
+err:
+       return ret;
+}
+
 #include "drm_selftest.c"
 
 static int __init test_drm_mm_init(void)