[igt-dev] [PATCH i-g-t 1/3] i915/gem_exec_schedule: Make gem_exec_schedule understand static priority mapping

[Matthew Brost <matthew.brost@intel.com>]

The i915 currently has 2k visible priority levels which are currently
unique. This is changing to statically map these 2k levels into 3
buckets:

low: < 0
mid: 0
high: > 0

Update gem_exec_schedule to understand this. This entails updating
promotion test to use 3 levels that will map into different buckets and
also add bit of delay after releasing a cork beforing completing the
spinners to give time to the i915 schedule to process the fence and
release and queue the requests.

Also skip any tests that rely on having more than 3 priority levels.

v2: Add a delay between starting releasing spinner and cork in
promotion, add local define for static mapping engine info
v3:
 (Daniele)
  - Update commit message explaining why delay is needed,
    unconditionally add delay

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 lib/i915/gem_scheduler.c       | 14 +++++++++++
 lib/i915/gem_scheduler.h       |  1 +
 lib/i915/i915_drm_local.h      | 10 ++++++++
 tests/i915/gem_exec_schedule.c | 43 ++++++++++++++++++++++------------
 4 files changed, 53 insertions(+), 15 deletions(-)

diff --git a/lib/i915/gem_scheduler.c b/lib/i915/gem_scheduler.c
index cdddf42ad..d006b8676 100644
--- a/lib/i915/gem_scheduler.c
+++ b/lib/i915/gem_scheduler.c
@@ -28,6 +28,7 @@
 #include "igt_core.h"
 #include "ioctl_wrappers.h"
 
+#include "i915/i915_drm_local.h"
 #include "i915/gem_scheduler.h"
 #include "i915/gem_submission.h"
 
@@ -90,6 +91,19 @@ bool gem_scheduler_has_ctx_priority(int fd)
 		I915_SCHEDULER_CAP_PRIORITY;
 }
 
+/**
+ * gem_scheduler_has_static_priority:
+ * @fd: open i915 drm file descriptor
+ *
+ * Feature test macro to query whether the driver supports priority assigned
+ * from user space are statically mapping into 3 buckets.
+ */
+bool gem_scheduler_has_static_priority(int fd)
+{
+	return gem_scheduler_capability(fd) &
+		I915_SCHEDULER_CAP_STATIC_PRIORITY_MAP;
+}
+
 /**
  * gem_scheduler_has_preemption:
  * @fd: open i915 drm file descriptor
diff --git a/lib/i915/gem_scheduler.h b/lib/i915/gem_scheduler.h
index d43e84bd2..b00804f70 100644
--- a/lib/i915/gem_scheduler.h
+++ b/lib/i915/gem_scheduler.h
@@ -29,6 +29,7 @@
 unsigned gem_scheduler_capability(int fd);
 bool gem_scheduler_enabled(int fd);
 bool gem_scheduler_has_ctx_priority(int fd);
+bool gem_scheduler_has_static_priority(int fd);
 bool gem_scheduler_has_preemption(int fd);
 bool gem_scheduler_has_semaphores(int fd);
 bool gem_scheduler_has_engine_busy_stats(int fd);
diff --git a/lib/i915/i915_drm_local.h b/lib/i915/i915_drm_local.h
index dd646aedf..a1527ff21 100644
--- a/lib/i915/i915_drm_local.h
+++ b/lib/i915/i915_drm_local.h
@@ -20,6 +20,16 @@ extern "C" {
  * clean these up when kernel uapi headers are sync'd.
  */
 
+/*
+ * Indicates the 2k user priority levels are statically mapped into 3 buckets as
+ * follows:
+ *
+ * -1k to -1	Low priority
+ * 0		Normal priority
+ * 1 to 1k	Highest priority
+ */
+#define   I915_SCHEDULER_CAP_STATIC_PRIORITY_MAP	(1ul << 5)
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/tests/i915/gem_exec_schedule.c b/tests/i915/gem_exec_schedule.c
index 1f6f71db0..191eb558f 100644
--- a/tests/i915/gem_exec_schedule.c
+++ b/tests/i915/gem_exec_schedule.c
@@ -247,6 +247,7 @@ static void unplug_show_queue(int fd, struct igt_cork *c,
 
 	igt_cork_unplug(c); /* batches will now be queued on the engine */
 	igt_debugfs_dump(fd, "i915_engine_info");
+	usleep(250000);
 
 	for (int n = 0; n < max; n++) {
 		uint64_t ahnd = spin[n]->ahnd;
@@ -1469,10 +1470,10 @@ static void promotion(int fd, const intel_ctx_cfg_t *cfg, unsigned ring)
 	gem_context_set_priority(fd, ctx[LO]->id, MIN_PRIO);
 
 	ctx[HI] = intel_ctx_create(fd, cfg);
-	gem_context_set_priority(fd, ctx[HI]->id, 0);
+	gem_context_set_priority(fd, ctx[HI]->id, MAX_PRIO);
 
 	ctx[NOISE] = intel_ctx_create(fd, cfg);
-	gem_context_set_priority(fd, ctx[NOISE]->id, MIN_PRIO/2);
+	gem_context_set_priority(fd, ctx[NOISE]->id, 0);
 
 	result = gem_create(fd, 4096);
 	result_offset = get_offset(ahnd, result, 4096, 0);
@@ -3246,19 +3247,25 @@ igt_main
 			test_each_engine_store("preempt-other-chain", fd, ctx, e)
 				preempt_other(fd, &ctx->cfg, e->flags, CHAIN);
 
-			test_each_engine_store("preempt-queue", fd, ctx, e)
-				preempt_queue(fd, &ctx->cfg, e->flags, 0);
+			test_each_engine_store("preempt-engines", fd, ctx, e)
+				preempt_engines(fd, e, 0);
 
-			test_each_engine_store("preempt-queue-chain", fd, ctx, e)
-				preempt_queue(fd, &ctx->cfg, e->flags, CHAIN);
-			test_each_engine_store("preempt-queue-contexts", fd, ctx, e)
-				preempt_queue(fd, &ctx->cfg, e->flags, CONTEXTS);
+			igt_subtest_group {
+				igt_fixture {
+					igt_require(!gem_scheduler_has_static_priority(fd));
+				}
 
-			test_each_engine_store("preempt-queue-contexts-chain", fd, ctx, e)
-				preempt_queue(fd, &ctx->cfg, e->flags, CONTEXTS | CHAIN);
+				test_each_engine_store("preempt-queue", fd, ctx, e)
+					preempt_queue(fd, &ctx->cfg, e->flags, 0);
 
-			test_each_engine_store("preempt-engines", fd, ctx, e)
-				preempt_engines(fd, e, 0);
+				test_each_engine_store("preempt-queue-chain", fd, ctx, e)
+					preempt_queue(fd, &ctx->cfg, e->flags, CHAIN);
+				test_each_engine_store("preempt-queue-contexts", fd, ctx, e)
+					preempt_queue(fd, &ctx->cfg, e->flags, CONTEXTS);
+
+				test_each_engine_store("preempt-queue-contexts-chain", fd, ctx, e)
+					preempt_queue(fd, &ctx->cfg, e->flags, CONTEXTS | CHAIN);
+			}
 
 			igt_subtest_group {
 				igt_hang_t hang;
@@ -3300,11 +3307,17 @@ igt_main
 		test_each_engine_store("wide", fd, ctx, e)
 			wide(fd, &ctx->cfg, e->flags);
 
-		test_each_engine_store("reorder-wide", fd, ctx, e)
-			reorder_wide(fd, &ctx->cfg, e->flags);
-
 		test_each_engine_store("smoketest", fd, ctx, e)
 			smoketest(fd, &ctx->cfg, e->flags, 5);
+
+		igt_subtest_group {
+			igt_fixture {
+				igt_require(!gem_scheduler_has_static_priority(fd));
+			}
+
+			test_each_engine_store("reorder-wide", fd, ctx, e)
+				reorder_wide(fd, &ctx->cfg, e->flags);
+		}
 	}
 
 	igt_subtest_group {
-- 
2.32.0