drm/i915/selftests: Add a simple exerciser for suspend/hibernate

Commit Message

Chris Wilson Aug. 29, 2018, 10:20 p.m. UTC

Although we cannot do a full system-level test of suspend/hibernate from
deep with the kernel selftests, we can exercise the GEM subsystem in
isolation and simulate the external effects (such as losing stolen
contents and trashing the register state).

Signed-off-by: Chris Wilson <[e-mail]>
Cc: Jakub Bartmiński <[e-mail]>
Cc: Matthew Auld <[e-mail]>
Cc: Joonas Lahtinen <[e-mail]>
---
 drivers/gpu/drm/i915/i915_gem.c               |   1 +
 drivers/gpu/drm/i915/selftests/i915_gem.c     | 173 ++++++++++++++++++
 .../drm/i915/selftests/i915_live_selftests.h  |   1 +
 3 files changed, 175 insertions(+)
 create mode 100644 drivers/gpu/drm/i915/selftests/i915_gem.c

Patch

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 0453eb42a1a3..7b7bbfe59697 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -6207,4 +6207,5 @@  int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)
 #include "selftests/huge_pages.c"
 #include "selftests/i915_gem_object.c"
 #include "selftests/i915_gem_coherency.c"
+#include "selftests/i915_gem.c"
 #endif
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem.c b/drivers/gpu/drm/i915/selftests/i915_gem.c
new file mode 100644
index 000000000000..1714643474d5
--- /dev/null
+++ b/drivers/gpu/drm/i915/selftests/i915_gem.c
@@ -0,0 +1,173 @@ 
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2018 Intel Corporation
+ */
+
+#include <linux/random.h>
+
+#include "../i915_selftest.h"
+
+#include "mock_context.h"
+#include "igt_flush_test.h"
+
+static int switch_to_context(struct drm_i915_private *i915,
+			     struct i915_gem_context *ctx)
+{
+	struct intel_engine_cs *engine;
+	enum intel_engine_id id;
+	int err = 0;
+
+	for_each_engine(engine, i915, id) {
+		struct i915_request *rq;
+
+		rq = i915_request_alloc(engine, ctx);
+		if (IS_ERR(rq)) {
+			err = PTR_ERR(rq);
+			break;
+		}
+
+		i915_request_add(rq);
+	}
+
+	return err;
+}
+
+static void trash_stolen(struct drm_i915_private *i915)
+{
+	struct i915_ggtt *ggtt = &i915->ggtt;
+	const u64 slot = ggtt->error_capture.start;
+	const resource_size_t size = resource_size(&i915->dsm);
+	unsigned long page;
+	u32 prng = 0x12345678;
+
+	for (page = 0; page < size; page += PAGE_SIZE) {
+		const dma_addr_t dma = i915->dsm.start + page;
+		u32 __iomem *s;
+		int x;
+
+		ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
+
+		s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
+		for (x = 0; x < PAGE_SIZE/sizeof(u32); x++)
+			s[x] = prng = next_pseudo_random32(prng);
+		io_mapping_unmap_atomic(s);
+	}
+
+	ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
+}
+
+static void simulate_hibernate(struct drm_i915_private *i915)
+{
+	/*
+	 * As a final sting in the tail, invalidate stolen. Under a real S4,
+	 * stolen is lost and needs to be refilled on resume. However, under
+	 * CI we merely do S4-device testing (as full S4 is too unreliable
+	 * for automated testing across a cluster), so to simulate the effect
+	 * of stolen being trashed across S4, we trash it ourselves.
+	 */
+	trash_stolen(i915);
+}
+
+static int igt_gem_suspend(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct i915_gem_context *ctx;
+	struct drm_file *file;
+	int err;
+
+	file = mock_file(i915);
+	if (IS_ERR(file))
+		return PTR_ERR(file);
+
+	err = -ENOMEM;
+	mutex_lock(&i915->drm.struct_mutex);
+	ctx = live_context(i915, file);
+	if (!IS_ERR(ctx))
+		err = switch_to_context(i915, ctx);
+	mutex_unlock(&i915->drm.struct_mutex);
+	if (err)
+		goto out;
+
+	if (i915_gem_suspend(i915)) {
+		pr_err("i915_gem_suspend failed\n");
+		err = -EINVAL;
+		goto out;
+	}
+
+	i915_gem_suspend_late(i915);
+
+	/* Here be dragons! Note that with S3RST any S3 may become S4! */
+	simulate_hibernate(i915);
+
+	intel_engines_sanitize(i915);
+	i915_gem_sanitize(i915);
+
+	i915_gem_resume(i915);
+
+	mutex_lock(&i915->drm.struct_mutex);
+	err = switch_to_context(i915, ctx);
+	if (igt_flush_test(i915, I915_WAIT_LOCKED))
+		err = -EIO;
+	mutex_unlock(&i915->drm.struct_mutex);
+out:
+	mock_file_free(i915, file);
+	return err;
+}
+
+static int igt_gem_hibernate(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct i915_gem_context *ctx;
+	struct drm_file *file;
+	int err;
+
+	file = mock_file(i915);
+	if (IS_ERR(file))
+		return PTR_ERR(file);
+
+	err = -ENOMEM;
+	mutex_lock(&i915->drm.struct_mutex);
+	ctx = live_context(i915, file);
+	if (!IS_ERR(ctx))
+		err = switch_to_context(i915, ctx);
+	mutex_unlock(&i915->drm.struct_mutex);
+	if (err)
+		goto out;
+
+	if (i915_gem_suspend(i915)) {
+		pr_err("i915_gem_suspend failed\n");
+		err = -EINVAL;
+		goto out;
+	}
+
+	i915_gem_freeze(i915);
+	i915_gem_freeze_late(i915);
+
+	/* Here be dragons! */
+	simulate_hibernate(i915);
+
+	intel_engines_sanitize(i915);
+	i915_gem_sanitize(i915);
+
+	i915_gem_resume(i915);
+
+	mutex_lock(&i915->drm.struct_mutex);
+	err = switch_to_context(i915, ctx);
+	if (igt_flush_test(i915, I915_WAIT_LOCKED))
+		err = -EIO;
+	mutex_unlock(&i915->drm.struct_mutex);
+out:
+	mock_file_free(i915, file);
+	return err;
+}
+
+int i915_gem_live_selftests(struct drm_i915_private *i915)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(igt_gem_suspend),
+		SUBTEST(igt_gem_hibernate),
+	};
+
+	return i915_subtests(tests, i915);
+}
diff --git a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
index a00e2bd08bce..a15713cae3b3 100644
--- a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
+++ b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
@@ -17,6 +17,7 @@  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(gem, i915_gem_live_selftests)
 selftest(evict, i915_gem_evict_live_selftests)
 selftest(hugepages, i915_gem_huge_page_live_selftests)
 selftest(contexts, i915_gem_context_live_selftests)