[PATCH 44/83] drm/i915: Simple selftest to exercise live requests

[Chris Wilson]

Just create several batches of requests and expect it to not fall over!

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/selftests/i915_gem_request.c  | 78 ++++++++++++++++++++++
 .../gpu/drm/i915/selftests/i915_live_selftests.h   |  1 +
 2 files changed, 79 insertions(+)

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_request.c b/drivers/gpu/drm/i915/selftests/i915_gem_request.c
index f348f5f81351..63e69d360764 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_request.c
@@ -22,6 +22,8 @@
  *
  */
 
+#include <linux/prime_numbers.h>
+
 #include "i915_selftest.h"
 
 #include "mock_gem_device.h"
@@ -155,3 +157,79 @@ int i915_gem_request_mock_selftests(void)
 
 	return err;
 }
+
+static int live_nop_request(void *arg)
+{
+	I915_SELFTEST_TIMEOUT(end_time);
+	struct drm_i915_private *i915 = arg;
+	struct drm_i915_gem_request *request;
+	unsigned int reset_count = i915_reset_count(&i915->gpu_error);
+	unsigned long n, prime;
+	ktime_t times[2] = {};
+	int err;
+
+	mutex_lock(&i915->drm.struct_mutex);
+
+	err = i915_gem_wait_for_idle(i915, I915_WAIT_LOCKED);
+	if (err) {
+		pr_err("Failed to idle GPU before %s\n", __func__);
+		goto out_unlock;
+	}
+
+	i915->gpu_error.missed_irq_rings = 0;
+
+	for_each_prime_number_from(prime, 1, 8192) {
+		times[1] = ktime_get_raw();
+
+		for (n = 0; n < prime; n++) {
+			request = i915_gem_request_alloc(i915->engine[RCS],
+							 i915->kernel_context);
+			if (IS_ERR(request)) {
+				err = PTR_ERR(request);
+				goto out_unlock;
+			}
+
+			i915_add_request(request);
+		}
+		i915_wait_request(request, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);
+		times[1] = ktime_sub(ktime_get_raw(), times[1]);
+		if (prime == 1)
+			times[0] = times[1];
+
+		if (time_after(jiffies, end_time)) {
+			pr_warn("%s timed out: last batch size %lu\n",
+				__func__, prime);
+			break;
+		}
+	}
+
+	if (reset_count != i915_reset_count(&i915->gpu_error)) {
+		pr_err("GPU was reset %d times!\n",
+		       i915_reset_count(&i915->gpu_error) - reset_count);
+		err = -EIO;
+		goto out_unlock;
+	}
+
+	if (i915->gpu_error.missed_irq_rings) {
+		pr_err("Missed interrupts on rings %lx\n",
+		       i915->gpu_error.missed_irq_rings);
+		err = -EIO;
+		goto out_unlock;
+	}
+
+	pr_info("Request latencies: 1 = %lluns, %lu = %lluns\n",
+	       ktime_to_ns(times[0]),
+	       prime, div64_u64(ktime_to_ns(times[1]), prime));
+
+out_unlock:
+	mutex_unlock(&i915->drm.struct_mutex);
+	return err;
+}
+
+int i915_gem_request_live_selftests(struct drm_i915_private *i915)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(live_nop_request),
+	};
+	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 f3e17cb10e05..09bf538826df 100644
--- a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
+++ b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
@@ -9,3 +9,4 @@
  * Tests are executed in order by igt/drv_selftest
  */
 selftest(sanitycheck, i915_live_sanitycheck) /* keep first (igt selfcheck) */
+selftest(requests, i915_gem_request_live_selftests)
-- 
2.11.0