drm/i915/selftests: prefer random sizes for the huge-GTT-page smoke tests

Ditch the dubious static list of sizes to enumerate, in favour of
choosing a random size within the limits of each backing store. With
repeated CI runs this should give us a wider range of object sizes, and
in turn more page-size combinations, while using less machine time.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191025153728.23689-6-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
index fa134a8..b777999 100644 (file)
--- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
+++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
@@ -1317,204 +1317,137 @@ out_device:
        return err;
 }
 
-static int igt_ppgtt_internal_huge(void *arg)
-{
-       struct i915_gem_context *ctx = arg;
-       struct drm_i915_private *i915 = ctx->i915;
-       struct drm_i915_gem_object *obj;
-       static const unsigned int sizes[] = {
-               SZ_64K,
-               SZ_128K,
-               SZ_256K,
-               SZ_512K,
-               SZ_1M,
-               SZ_2M,
-       };
-       int i;
-       int err;
-
-       /*
-        * Sanity check that the HW uses huge pages correctly through internal
-        * -- ensure that our writes land in the right place.
-        */
-
-       for (i = 0; i < ARRAY_SIZE(sizes); ++i) {
-               unsigned int size = sizes[i];
-
-               obj = i915_gem_object_create_internal(i915, size);
-               if (IS_ERR(obj))
-                       return PTR_ERR(obj);
-
-               err = i915_gem_object_pin_pages(obj);
-               if (err)
-                       goto out_put;
-
-               if (obj->mm.page_sizes.phys < I915_GTT_PAGE_SIZE_64K) {
-                       pr_info("internal unable to allocate huge-page(s) with size=%u\n",
-                               size);
-                       goto out_unpin;
-               }
-
-               err = igt_write_huge(ctx, obj);
-               if (err) {
-                       pr_err("internal write-huge failed with size=%u\n",
-                              size);
-                       goto out_unpin;
-               }
-
-               i915_gem_object_unpin_pages(obj);
-               __i915_gem_object_put_pages(obj, I915_MM_NORMAL);
-               i915_gem_object_put(obj);
-       }
-
-       return 0;
-
-out_unpin:
-       i915_gem_object_unpin_pages(obj);
-out_put:
-       i915_gem_object_put(obj);
-
-       return err;
-}
+typedef struct drm_i915_gem_object *
+(*igt_create_fn)(struct drm_i915_private *i915, u32 size, u32 flags);
 
 static inline bool igt_can_allocate_thp(struct drm_i915_private *i915)
 {
        return i915->mm.gemfs && has_transparent_hugepage();
 }
 
-static int igt_ppgtt_gemfs_huge(void *arg)
+static struct drm_i915_gem_object *
+igt_create_shmem(struct drm_i915_private *i915, u32 size, u32 flags)
 {
-       struct i915_gem_context *ctx = arg;
-       struct drm_i915_private *i915 = ctx->i915;
-       struct drm_i915_gem_object *obj;
-       static const unsigned int sizes[] = {
-               SZ_2M,
-               SZ_4M,
-               SZ_8M,
-               SZ_16M,
-               SZ_32M,
-       };
-       int i;
-       int err;
-
-       /*
-        * Sanity check that the HW uses huge pages correctly through gemfs --
-        * ensure that our writes land in the right place.
-        */
-
        if (!igt_can_allocate_thp(i915)) {
-               pr_info("missing THP support, skipping\n");
-               return 0;
+               pr_info("%s missing THP support, skipping\n", __func__);
+               return ERR_PTR(-ENODEV);
        }
 
-       for (i = 0; i < ARRAY_SIZE(sizes); ++i) {
-               unsigned int size = sizes[i];
-
-               obj = i915_gem_object_create_shmem(i915, size);
-               if (IS_ERR(obj))
-                       return PTR_ERR(obj);
-
-               err = i915_gem_object_pin_pages(obj);
-               if (err)
-                       goto out_put;
+       return i915_gem_object_create_shmem(i915, size);
+}
 
-               if (obj->mm.page_sizes.phys < I915_GTT_PAGE_SIZE_2M) {
-                       pr_info("finishing test early, gemfs unable to allocate huge-page(s) with size=%u\n",
-                               size);
-                       goto out_unpin;
-               }
+static struct drm_i915_gem_object *
+igt_create_internal(struct drm_i915_private *i915, u32 size, u32 flags)
+{
+       return i915_gem_object_create_internal(i915, size);
+}
 
-               err = igt_write_huge(ctx, obj);
-               if (err) {
-                       pr_err("gemfs write-huge failed with size=%u\n",
-                              size);
-                       goto out_unpin;
-               }
+static struct drm_i915_gem_object *
+igt_create_local(struct drm_i915_private *i915, u32 size, u32 flags)
+{
+       return i915_gem_object_create_lmem(i915, size, flags);
+}
 
-               i915_gem_object_unpin_pages(obj);
-               __i915_gem_object_put_pages(obj, I915_MM_NORMAL);
-               i915_gem_object_put(obj);
-       }
+static u32 igt_random_size(struct rnd_state *prng,
+                          u32 min_page_size,
+                          u32 max_page_size)
+{
+       u64 mask;
+       u32 size;
 
-       return 0;
+       GEM_BUG_ON(!is_power_of_2(min_page_size));
+       GEM_BUG_ON(!is_power_of_2(max_page_size));
+       GEM_BUG_ON(min_page_size < PAGE_SIZE);
+       GEM_BUG_ON(min_page_size > max_page_size);
 
-out_unpin:
-       i915_gem_object_unpin_pages(obj);
-out_put:
-       i915_gem_object_put(obj);
+       mask = ((max_page_size << 1ULL) - 1) & PAGE_MASK;
+       size = prandom_u32_state(prng) & mask;
+       if (size < min_page_size)
+               size |= min_page_size;
 
-       return err;
+       return size;
 }
 
-static int igt_ppgtt_lmem_huge(void *arg)
+static int igt_ppgtt_smoke_huge(void *arg)
 {
        struct i915_gem_context *ctx = arg;
        struct drm_i915_private *i915 = ctx->i915;
        struct drm_i915_gem_object *obj;
-       static const unsigned int sizes[] = {
-               SZ_64K,
-               SZ_512K,
-               SZ_1M,
-               SZ_2M,
+       I915_RND_STATE(prng);
+       struct {
+               igt_create_fn fn;
+               u32 min;
+               u32 max;
+       } backends[] = {
+               { igt_create_internal, SZ_64K, SZ_2M,  },
+               { igt_create_shmem,    SZ_64K, SZ_32M, },
+               { igt_create_local,    SZ_64K, SZ_1G,  },
        };
-       int i;
        int err;
-
-       if (!HAS_LMEM(i915)) {
-               pr_info("device lacks LMEM support, skipping\n");
-               return 0;
-       }
+       int i;
 
        /*
-        * Sanity check that the HW uses huge pages correctly through LMEM
-        * -- ensure that our writes land in the right place.
+        * Sanity check that the HW uses huge pages correctly through our
+        * various backends -- ensure that our writes land in the right place.
         */
 
-       for (i = 0; i < ARRAY_SIZE(sizes); ++i) {
-               unsigned int size = sizes[i];
+       for (i = 0; i < ARRAY_SIZE(backends); ++i) {
+               u32 min = backends[i].min;
+               u32 max = backends[i].max;
+               u32 size = max;
+try_again:
+               size = igt_random_size(&prng, min, rounddown_pow_of_two(size));
 
-               obj = i915_gem_object_create_lmem(i915, size,
-                                                 I915_BO_ALLOC_CONTIGUOUS);
+               obj = backends[i].fn(i915, size, 0);
                if (IS_ERR(obj)) {
                        err = PTR_ERR(obj);
                        if (err == -E2BIG) {
-                               pr_info("object too big for region!\n");
-                               return 0;
+                               size >>= 1;
+                               goto try_again;
+                       } else if (err == -ENODEV) {
+                               err = 0;
+                               continue;
                        }
 
                        return err;
                }
 
                err = i915_gem_object_pin_pages(obj);
-               if (err)
+               if (err) {
+                       if (err == -ENXIO) {
+                               i915_gem_object_put(obj);
+                               size >>= 1;
+                               goto try_again;
+                       }
                        goto out_put;
+               }
 
-               if (obj->mm.page_sizes.phys < I915_GTT_PAGE_SIZE_64K) {
-                       pr_info("LMEM unable to allocate huge-page(s) with size=%u\n",
-                               size);
+               if (obj->mm.page_sizes.phys < min) {
+                       pr_info("%s unable to allocate huge-page(s) with size=%u, i=%d\n",
+                               __func__, size, i);
+                       err = -ENOMEM;
                        goto out_unpin;
                }
 
                err = igt_write_huge(ctx, obj);
                if (err) {
-                       pr_err("LMEM write-huge failed with size=%u\n", size);
-                       goto out_unpin;
+                       pr_err("%s write-huge failed with size=%u, i=%d\n",
+                              __func__, size, i);
                }
-
+out_unpin:
                i915_gem_object_unpin_pages(obj);
                __i915_gem_object_put_pages(obj, I915_MM_NORMAL);
+out_put:
                i915_gem_object_put(obj);
-       }
 
-       return 0;
+               if (err == -ENOMEM || err == -ENXIO)
+                       err = 0;
 
-out_unpin:
-       i915_gem_object_unpin_pages(obj);
-out_put:
-       i915_gem_object_put(obj);
+               if (err)
+                       break;
 
-       if (err == -ENOMEM)
-               err = 0;
+               cond_resched();
+       }
 
        return err;
 }
@@ -1878,9 +1811,7 @@ int i915_gem_huge_page_live_selftests(struct drm_i915_private *i915)
                SUBTEST(igt_ppgtt_pin_update),
                SUBTEST(igt_tmpfs_fallback),
                SUBTEST(igt_ppgtt_exhaust_huge),
-               SUBTEST(igt_ppgtt_gemfs_huge),
-               SUBTEST(igt_ppgtt_internal_huge),
-               SUBTEST(igt_ppgtt_lmem_huge),
+               SUBTEST(igt_ppgtt_smoke_huge),
        };
        struct drm_file *file;
        struct i915_gem_context *ctx;