drm/i915: Live testing for context execution

Check we can create and execution within a context.

v2: Write one set of dwords through each context/engine to exercise more
contexts within the same time period.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170213171558.20942-38-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem_context.c

@@ -1202,4 +1202,5 @@ int i915_gem_context_reset_stats_ioctl(struct drm_device *dev,
 
 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 #include "selftests/mock_context.c"
+#include "selftests/i915_gem_context.c"
 #endif

drivers/gpu/drm/i915/selftests/i915_gem_context.c

+/*
+ * Copyright © 2017 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+#include "../i915_selftest.h"
+
+#include "mock_drm.h"
+#include "huge_gem_object.h"
+
+#define DW_PER_PAGE (PAGE_SIZE / sizeof(u32))
+
+static struct i915_vma *
+gpu_fill_dw(struct i915_vma *vma, u64 offset, unsigned long count, u32 value)
+{
+	struct drm_i915_gem_object *obj;
+	const int gen = INTEL_GEN(vma->vm->i915);
+	unsigned long n, size;
+	u32 *cmd;
+	int err;
+
+	GEM_BUG_ON(!igt_can_mi_store_dword_imm(vma->vm->i915));
+
+	size = (4 * count + 1) * sizeof(u32);
+	size = round_up(size, PAGE_SIZE);
+	obj = i915_gem_object_create_internal(vma->vm->i915, size);
+	if (IS_ERR(obj))
+		return ERR_CAST(obj);
+
+	cmd = i915_gem_object_pin_map(obj, I915_MAP_WB);
+	if (IS_ERR(cmd)) {
+		err = PTR_ERR(cmd);
+		goto err;
+	}
+
+	GEM_BUG_ON(offset + (count - 1) * PAGE_SIZE > vma->node.size);
+	offset += vma->node.start;
+
+	for (n = 0; n < count; n++) {
+		if (gen >= 8) {
+			*cmd++ = MI_STORE_DWORD_IMM_GEN4;
+			*cmd++ = lower_32_bits(offset);
+			*cmd++ = upper_32_bits(offset);
+			*cmd++ = value;
+		} else if (gen >= 4) {
+			*cmd++ = MI_STORE_DWORD_IMM_GEN4 |
+				(gen < 6 ? 1 << 22 : 0);
+			*cmd++ = 0;
+			*cmd++ = offset;
+			*cmd++ = value;
+		} else {
+			*cmd++ = MI_STORE_DWORD_IMM | 1 << 22;
+			*cmd++ = offset;
+			*cmd++ = value;
+		}
+		offset += PAGE_SIZE;
+	}
+	*cmd = MI_BATCH_BUFFER_END;
+	i915_gem_object_unpin_map(obj);
+
+	err = i915_gem_object_set_to_gtt_domain(obj, false);
+	if (err)
+		goto err;
+
+	vma = i915_vma_instance(obj, vma->vm, NULL);
+	if (IS_ERR(vma)) {
+		err = PTR_ERR(vma);
+		goto err;
+	}
+
+	err = i915_vma_pin(vma, 0, 0, PIN_USER);
+	if (err)
+		goto err;
+
+	return vma;
+
+err:
+	i915_gem_object_put(obj);
+	return ERR_PTR(err);
+}
+
+static unsigned long real_page_count(struct drm_i915_gem_object *obj)
+{
+	return huge_gem_object_phys_size(obj) >> PAGE_SHIFT;
+}
+
+static unsigned long fake_page_count(struct drm_i915_gem_object *obj)
+{
+	return huge_gem_object_dma_size(obj) >> PAGE_SHIFT;
+}
+
+static int gpu_fill(struct drm_i915_gem_object *obj,
+		    struct i915_gem_context *ctx,
+		    struct intel_engine_cs *engine,
+		    unsigned int dw)
+{
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
+	struct i915_address_space *vm =
+		ctx->ppgtt ? &ctx->ppgtt->base : &i915->ggtt.base;
+	struct drm_i915_gem_request *rq;
+	struct i915_vma *vma;
+	struct i915_vma *batch;
+	unsigned int flags;
+	int err;
+
+	GEM_BUG_ON(obj->base.size > vm->total);
+
+	vma = i915_vma_instance(obj, vm, NULL);
+	if (IS_ERR(vma))
+		return PTR_ERR(vma);
+
+	err = i915_gem_object_set_to_gtt_domain(obj, false);
+	if (err)
+		return err;
+
+	err = i915_vma_pin(vma, 0, 0, PIN_HIGH | PIN_USER);
+	if (err)
+		return err;
+
+	/* Within the GTT the huge objects maps every page onto
+	 * its 1024 real pages (using phys_pfn = dma_pfn % 1024).
+	 * We set the nth dword within the page using the nth
+	 * mapping via the GTT - this should exercise the GTT mapping
+	 * whilst checking that each context provides a unique view
+	 * into the object.
+	 */
+	batch = gpu_fill_dw(vma,
+			    (dw * real_page_count(obj)) << PAGE_SHIFT |
+			    (dw * sizeof(u32)),
+			    real_page_count(obj),
+			    dw);
+	if (IS_ERR(batch)) {
+		err = PTR_ERR(batch);
+		goto err_vma;
+	}
+
+	rq = i915_gem_request_alloc(engine, ctx);
+	if (IS_ERR(rq)) {
+		err = PTR_ERR(rq);
+		goto err_batch;
+	}
+
+	err = engine->emit_flush(rq, EMIT_INVALIDATE);
+	if (err)
+		goto err_request;
+
+	err = i915_switch_context(rq);
+	if (err)
+		goto err_request;
+
+	flags = 0;
+	if (INTEL_GEN(vm->i915) <= 5)
+		flags |= I915_DISPATCH_SECURE;
+
+	err = engine->emit_bb_start(rq,
+				    batch->node.start, batch->node.size,
+				    flags);
+	if (err)
+		goto err_request;
+
+	i915_vma_move_to_active(batch, rq, 0);
+	i915_gem_object_set_active_reference(batch->obj);
+	i915_vma_unpin(batch);
+	i915_vma_close(batch);
+
+	i915_vma_move_to_active(vma, rq, 0);
+	i915_vma_unpin(vma);
+
+	reservation_object_lock(obj->resv, NULL);
+	reservation_object_add_excl_fence(obj->resv, &rq->fence);
+	reservation_object_unlock(obj->resv);
+
+	__i915_add_request(rq, true);
+
+	return 0;
+
+err_request:
+	__i915_add_request(rq, false);
+err_batch:
+	i915_vma_unpin(batch);
+err_vma:
+	i915_vma_unpin(vma);
+	return err;
+}
+
+static int cpu_fill(struct drm_i915_gem_object *obj, u32 value)
+{
+	const bool has_llc = HAS_LLC(to_i915(obj->base.dev));
+	unsigned int n, m, need_flush;
+	int err;
+
+	err = i915_gem_obj_prepare_shmem_write(obj, &need_flush);
+	if (err)
+		return err;
+
+	for (n = 0; n < real_page_count(obj); n++) {
+		u32 *map;
+
+		map = kmap_atomic(i915_gem_object_get_page(obj, n));
+		for (m = 0; m < DW_PER_PAGE; m++)
+			map[m] = value;
+		if (!has_llc)
+			drm_clflush_virt_range(map, PAGE_SIZE);
+		kunmap_atomic(map);
+	}
+
+	i915_gem_obj_finish_shmem_access(obj);
+	obj->base.read_domains = I915_GEM_DOMAIN_GTT | I915_GEM_DOMAIN_CPU;
+	obj->base.write_domain = 0;
+	return 0;
+}
+
+static int cpu_check(struct drm_i915_gem_object *obj, unsigned int max)
+{
+	unsigned int n, m, needs_flush;
+	int err;
+
+	err = i915_gem_obj_prepare_shmem_read(obj, &needs_flush);
+	if (err)
+		return err;
+
+	for (n = 0; n < real_page_count(obj); n++) {
+		u32 *map;
+
+		map = kmap_atomic(i915_gem_object_get_page(obj, n));
+		if (needs_flush & CLFLUSH_BEFORE)
+			drm_clflush_virt_range(map, PAGE_SIZE);
+
+		for (m = 0; m < max; m++) {
+			if (map[m] != m) {
+				pr_err("Invalid value at page %d, offset %d: found %x expected %x\n",
+				       n, m, map[m], m);
+				err = -EINVAL;
+				goto out_unmap;
+			}
+		}
+
+		for (; m < DW_PER_PAGE; m++) {
+			if (map[m] != 0xdeadbeef) {
+				pr_err("Invalid value at page %d, offset %d: found %x expected %x\n",
+				       n, m, map[m], 0xdeadbeef);
+				err = -EINVAL;
+				goto out_unmap;
+			}
+		}
+
+out_unmap:
+		kunmap_atomic(map);
+		if (err)
+			break;
+	}
+
+	i915_gem_obj_finish_shmem_access(obj);
+	return err;
+}
+
+static struct drm_i915_gem_object *
+create_test_object(struct i915_gem_context *ctx,
+		   struct drm_file *file,
+		   struct list_head *objects)
+{
+	struct drm_i915_gem_object *obj;
+	struct i915_address_space *vm =
+		ctx->ppgtt ? &ctx->ppgtt->base : &ctx->i915->ggtt.base;
+	u64 size;
+	u32 handle;
+	int err;
+
+	size = min(vm->total / 2, 1024ull * DW_PER_PAGE * PAGE_SIZE);
+	size = round_down(size, DW_PER_PAGE * PAGE_SIZE);
+
+	obj = huge_gem_object(ctx->i915, DW_PER_PAGE * PAGE_SIZE, size);
+	if (IS_ERR(obj))
+		return obj;
+
+	/* tie the handle to the drm_file for easy reaping */
+	err = drm_gem_handle_create(file, &obj->base, &handle);
+	i915_gem_object_put(obj);
+	if (err)
+		return ERR_PTR(err);
+
+	err = cpu_fill(obj, 0xdeadbeef);
+	if (err) {
+		pr_err("Failed to fill object with cpu, err=%d\n",
+		       err);
+		return ERR_PTR(err);
+	}
+
+	list_add_tail(&obj->st_link, objects);
+	return obj;
+}
+
+static unsigned long max_dwords(struct drm_i915_gem_object *obj)
+{
+	unsigned long npages = fake_page_count(obj);
+
+	GEM_BUG_ON(!IS_ALIGNED(npages, DW_PER_PAGE));
+	return npages / DW_PER_PAGE;
+}
+
+static int igt_ctx_exec(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct drm_file *file = mock_file(i915);
+	struct drm_i915_gem_object *obj;
+	IGT_TIMEOUT(end_time);
+	LIST_HEAD(objects);
+	unsigned long ncontexts, ndwords, dw;
+	int err;
+
+	/* Create a few different contexts (with different mm) and write
+	 * through each ctx/mm using the GPU making sure those writes end
+	 * up in the expected pages of our obj.
+	 */
+
+	mutex_lock(&i915->drm.struct_mutex);
+
+	ncontexts = 0;
+	ndwords = 0;
+	dw = 0;
+	while (!time_after(jiffies, end_time)) {
+		struct intel_engine_cs *engine;
+		struct i915_gem_context *ctx;
+		unsigned int id;
+
+		ctx = i915_gem_create_context(i915, file->driver_priv);
+		if (IS_ERR(ctx)) {
+			err = PTR_ERR(ctx);
+			goto out_unlock;
+		}
+
+		for_each_engine(engine, i915, id) {
+			if (dw == 0) {
+				obj = create_test_object(ctx, file, &objects);
+				if (IS_ERR(obj)) {
+					err = PTR_ERR(obj);
+					goto out_unlock;
+				}
+			}
+
+			err = gpu_fill(obj, ctx, engine, dw);
+			if (err) {
+				pr_err("Failed to fill dword %lu [%lu/%lu] with gpu (%s) in ctx %u [full-ppgtt? %s], err=%d\n",
+				       ndwords, dw, max_dwords(obj),
+				       engine->name, ctx->hw_id,
+				       yesno(!!ctx->ppgtt), err);
+				goto out_unlock;
+			}
+
+			if (++dw == max_dwords(obj))
+				dw = 0;
+			ndwords++;
+		}
+		ncontexts++;
+	}
+	pr_info("Submitted %lu contexts (across %u engines), filling %lu dwords\n",
+		ncontexts, INTEL_INFO(i915)->num_rings, ndwords);
+
+	dw = 0;
+	list_for_each_entry(obj, &objects, st_link) {
+		unsigned int rem =
+			min_t(unsigned int, ndwords - dw, max_dwords(obj));
+
+		err = cpu_check(obj, rem);
+		if (err)
+			break;
+
+		dw += rem;
+	}
+
+out_unlock:
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	mock_file_free(i915, file);
+	return err;
+}
+
+int i915_gem_context_live_selftests(struct drm_i915_private *i915)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(igt_ctx_exec),
+	};
+
+	return i915_subtests(tests, i915);
+}

drivers/gpu/drm/i915/selftests/i915_live_selftests.h

@@ -15,3 +15,4 @@ selftest(objects, i915_gem_object_live_selftests)
 selftest(dmabuf, i915_gem_dmabuf_live_selftests)
 selftest(coherency, i915_gem_coherency_live_selftests)
 selftest(gtt, i915_gem_gtt_live_selftests)
+selftest(contexts, i915_gem_context_live_selftests)