drm: kselftest for drm_mm_reserve_node()

Exercise drm_mm_reserve_node(), check that we can't reserve an already
occupied range and that the lists are correct after reserving/removing.

v2: Check for invalid node reservation.

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/20161222083641.2691-10-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 0265f09e92fa60227c262819d6ca4a3d403f3718..693d85677e7f76f534fea6225eea88a93f5b4d80 100644 (file)
--- a/drivers/gpu/drm/selftests/drm_mm_selftests.h
+++ b/drivers/gpu/drm/selftests/drm_mm_selftests.h
@@ -8,3 +8,4 @@
 selftest(sanitycheck, igt_sanitycheck) /* keep first (selfcheck for igt) */
 selftest(init, igt_init)
 selftest(debug, igt_debug)
+selftest(reserve, igt_reserve)

diff --git a/drivers/gpu/drm/selftests/test-drm_mm.c b/drivers/gpu/drm/selftests/test-drm_mm.c
index 434320061d9e284a27b007827267de123977f940..789a810d66aa20363141364b2bb25cc0686f08c1 100644 (file)
--- a/drivers/gpu/drm/selftests/test-drm_mm.c
+++ b/drivers/gpu/drm/selftests/test-drm_mm.c
@@ -80,6 +80,57 @@ static bool assert_one_hole(const struct drm_mm *mm, u64 start, u64 end)
        return ok;
 }
 
+static bool assert_continuous(const struct drm_mm *mm, u64 size)
+{
+       struct drm_mm_node *node, *check, *found;
+       unsigned long n;
+       u64 addr;
+
+       if (!assert_no_holes(mm))
+               return false;
+
+       n = 0;
+       addr = 0;
+       drm_mm_for_each_node(node, mm) {
+               if (node->start != addr) {
+                       pr_err("node[%ld] list out of order, expected %llx found %llx\n",
+                              n, addr, node->start);
+                       return false;
+               }
+
+               if (node->size != size) {
+                       pr_err("node[%ld].size incorrect, expected %llx, found %llx\n",
+                              n, size, node->size);
+                       return false;
+               }
+
+               if (node->hole_follows) {
+                       pr_err("node[%ld] is followed by a hole!\n", n);
+                       return false;
+               }
+
+               found = NULL;
+               drm_mm_for_each_node_in_range(check, mm, addr, addr + size) {
+                       if (node != check) {
+                               pr_err("lookup return wrong node, expected start %llx, found %llx\n",
+                                      node->start, check->start);
+                               return false;
+                       }
+                       found = check;
+               }
+               if (!found) {
+                       pr_err("lookup failed for node %llx + %llx\n",
+                              addr, size);
+                       return false;
+               }
+
+               addr += size;
+               n++;
+       }
+
+       return true;
+}
+
 static int igt_init(void *ignored)
 {
        const unsigned int size = 4096;
@@ -176,6 +227,230 @@ static int igt_debug(void *ignored)
        return 0;
 }
 
+static struct drm_mm_node *set_node(struct drm_mm_node *node,
+                                   u64 start, u64 size)
+{
+       node->start = start;
+       node->size = size;
+       return node;
+}
+
+static bool expect_reserve_fail(struct drm_mm *mm, struct drm_mm_node *node)
+{
+       int err;
+
+       err = drm_mm_reserve_node(mm, node);
+       if (likely(err == -ENOSPC))
+               return true;
+
+       if (!err) {
+               pr_err("impossible reserve succeeded, node %llu + %llu\n",
+                      node->start, node->size);
+               drm_mm_remove_node(node);
+       } else {
+               pr_err("impossible reserve failed with wrong error %d [expected %d], node %llu + %llu\n",
+                      err, -ENOSPC, node->start, node->size);
+       }
+       return false;
+}
+
+static bool check_reserve_boundaries(struct drm_mm *mm,
+                                    unsigned int count,
+                                    u64 size)
+{
+       const struct boundary {
+               u64 start, size;
+               const char *name;
+       } boundaries[] = {
+#define B(st, sz) { (st), (sz), "{ " #st ", " #sz "}" }
+               B(0, 0),
+               B(-size, 0),
+               B(size, 0),
+               B(size * count, 0),
+               B(-size, size),
+               B(-size, -size),
+               B(-size, 2*size),
+               B(0, -size),
+               B(size, -size),
+               B(count*size, size),
+               B(count*size, -size),
+               B(count*size, count*size),
+               B(count*size, -count*size),
+               B(count*size, -(count+1)*size),
+               B((count+1)*size, size),
+               B((count+1)*size, -size),
+               B((count+1)*size, -2*size),
+#undef B
+       };
+       struct drm_mm_node tmp = {};
+       int n;
+
+       for (n = 0; n < ARRAY_SIZE(boundaries); n++) {
+               if (!expect_reserve_fail(mm,
+                                        set_node(&tmp,
+                                                 boundaries[n].start,
+                                                 boundaries[n].size))) {
+                       pr_err("boundary[%d:%s] failed, count=%u, size=%lld\n",
+                              n, boundaries[n].name, count, size);
+                       return false;
+               }
+       }
+
+       return true;
+}
+
+static int __igt_reserve(unsigned int count, u64 size)
+{
+       DRM_RND_STATE(prng, random_seed);
+       struct drm_mm mm;
+       struct drm_mm_node tmp, *nodes, *node, *next;
+       unsigned int *order, n, m, o = 0;
+       int ret, err;
+
+       /* For exercising drm_mm_reserve_node(), we want to check that
+        * reservations outside of the drm_mm range are rejected, and to
+        * overlapping and otherwise already occupied ranges. Afterwards,
+        * the tree and nodes should be intact.
+        */
+
+       DRM_MM_BUG_ON(!count);
+       DRM_MM_BUG_ON(!size);
+
+       ret = -ENOMEM;
+       order = drm_random_order(count, &prng);
+       if (!order)
+               goto err;
+
+       nodes = vzalloc(sizeof(*nodes) * count);
+       if (!nodes)
+               goto err_order;
+
+       ret = -EINVAL;
+       drm_mm_init(&mm, 0, count * size);
+
+       if (!check_reserve_boundaries(&mm, count, size))
+               goto out;
+
+       for (n = 0; n < count; n++) {
+               nodes[n].start = order[n] * size;
+               nodes[n].size = size;
+
+               err = drm_mm_reserve_node(&mm, &nodes[n]);
+               if (err) {
+                       pr_err("reserve failed, step %d, start %llu\n",
+                              n, nodes[n].start);
+                       ret = err;
+                       goto out;
+               }
+
+               if (!drm_mm_node_allocated(&nodes[n])) {
+                       pr_err("reserved node not allocated! step %d, start %llu\n",
+                              n, nodes[n].start);
+                       goto out;
+               }
+
+               if (!expect_reserve_fail(&mm, &nodes[n]))
+                       goto out;
+       }
+
+       /* After random insertion the nodes should be in order */
+       if (!assert_continuous(&mm, size))
+               goto out;
+
+       /* Repeated use should then fail */
+       drm_random_reorder(order, count, &prng);
+       for (n = 0; n < count; n++) {
+               if (!expect_reserve_fail(&mm,
+                                        set_node(&tmp, order[n] * size, 1)))
+                       goto out;
+
+               /* Remove and reinsert should work */
+               drm_mm_remove_node(&nodes[order[n]]);
+               err = drm_mm_reserve_node(&mm, &nodes[order[n]]);
+               if (err) {
+                       pr_err("reserve failed, step %d, start %llu\n",
+                              n, nodes[n].start);
+                       ret = err;
+                       goto out;
+               }
+       }
+
+       if (!assert_continuous(&mm, size))
+               goto out;
+
+       /* Overlapping use should then fail */
+       for (n = 0; n < count; n++) {
+               if (!expect_reserve_fail(&mm, set_node(&tmp, 0, size*count)))
+                       goto out;
+       }
+       for (n = 0; n < count; n++) {
+               if (!expect_reserve_fail(&mm,
+                                        set_node(&tmp,
+                                                 size * n,
+                                                 size * (count - n))))
+                       goto out;
+       }
+
+       /* Remove several, reinsert, check full */
+       for_each_prime_number(n, min(max_prime, count)) {
+               for (m = 0; m < n; m++) {
+                       node = &nodes[order[(o + m) % count]];
+                       drm_mm_remove_node(node);
+               }
+
+               for (m = 0; m < n; m++) {
+                       node = &nodes[order[(o + m) % count]];
+                       err = drm_mm_reserve_node(&mm, node);
+                       if (err) {
+                               pr_err("reserve failed, step %d/%d, start %llu\n",
+                                      m, n, node->start);
+                               ret = err;
+                               goto out;
+                       }
+               }
+
+               o += n;
+
+               if (!assert_continuous(&mm, size))
+                       goto out;
+       }
+
+       ret = 0;
+out:
+       drm_mm_for_each_node_safe(node, next, &mm)
+               drm_mm_remove_node(node);
+       drm_mm_takedown(&mm);
+       vfree(nodes);
+err_order:
+       kfree(order);
+err:
+       return ret;
+}
+
+static int igt_reserve(void *ignored)
+{
+       const unsigned int count = min_t(unsigned int, BIT(10), max_iterations);
+       int n, ret;
+
+       for_each_prime_number_from(n, 1, 54) {
+               u64 size = BIT_ULL(n);
+
+               ret = __igt_reserve(count, size - 1);
+               if (ret)
+                       return ret;
+
+               ret = __igt_reserve(count, size);
+               if (ret)
+                       return ret;
+
+               ret = __igt_reserve(count, size + 1);
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+}
+
 #include "drm_selftest.c"
 
 static int __init test_drm_mm_init(void)